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• Volume 7, Issue 2
• Single-visit or multiple-visit root canal treatment: systematic review, meta-analysis and trial sequential analysis
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• Falk Schwendicke ,
• Gerd Göstemeyer
• Department of Operative and Preventive Dentistry , Charité—Universitätsmedizin Berlin , Berlin , Germany
• Correspondence to Dr Gerd Göstemeyer; gerd.goestemeyer{at}charite.de

Objectives Single-visit root canal treatment has some advantages over conventional multivisit treatment, but might increase the risk of complications. We systematically evaluated the risk of complications after single-visit or multiple-visit root canal treatment using meta-analysis and trial-sequential analysis.

Data Controlled trials comparing single-visit versus multiple-visit root canal treatment of permanent teeth were included. Trials needed to assess the risk of long-term complications (pain, infection, new/persisting/increasing periapical lesions ≥1 year after treatment), short-term pain or flare-up (acute exacerbation of initiation or continuation of root canal treatment).

Sources Electronic databases (PubMed, EMBASE, Cochrane Central) were screened, random-effects meta-analyses performed and trial-sequential analysis used to control for risk of random errors. Evidence was graded according to GRADE.

Study selection 29 trials (4341 patients) were included, all but 6 showing high risk of bias. Based on 10 trials (1257 teeth), risk of complications was not significantly different in single-visit versus multiple-visit treatment (risk ratio (RR) 1.00 (95% CI 0.75 to 1.35); weak evidence). Based on 20 studies (3008 teeth), risk of pain did not significantly differ between treatments (RR 0.99 (95% CI 0.76 to 1.30); moderate evidence). Risk of flare-up was recorded by 8 studies (1110 teeth) and was significantly higher after single-visit versus multiple-visit treatment (RR 2.13 (95% CI 1.16 to 3.89); very weak evidence). Trial-sequential analysis revealed that firm evidence for benefit, harm or futility was not reached for any of the outcomes.

Conclusions There is insufficient evidence to rule out whether important differences between both strategies exist.

Clinical significance Dentists can provide root canal treatment in 1 or multiple visits. Given the possibly increased risk of flare-ups, multiple-visit treatment might be preferred for certain teeth (eg, those with periapical lesions).

• Clinical outcomes
• Clinical studies/trials
• Comparative effectiveness research (CER)
• Endodontics
• Evidence-based dentistry/health care
• Systematic reviews and evidence-based medicine

This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/

https://doi.org/10.1136/bmjopen-2016-013115

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Strength and limitations of this study

This registered systematic review applies meta-analysis and trial-sequential analysis to assess the strength and quantity of the accrued evidence towards different root canal treatment strategies.

The synthesised estimates are supported only by moderate or weak evidence according to GRADE.

Firm evidence for benefit or harm of single-visit or multiple-visit root canal therapy as well as futility of further trials was not reached.

Introduction

After root canal treatment, teeth can experience short-term and/or long-term complications. Short-term complications include postoperative inflammation of periapical tissues leading to mild pain or flare-up (ie, an acute exacerbation of pulpal or periapical pathosis after root canal treatment, like severe unbearable pain and swelling). Pain and swelling have been associated with instrumentation or irrigation transporting medications, infected debris and bacteria into the periapical tissues. Inadequate instrumentation and disinfection lead to bacterial persistence within the root canals and consequent (re)contamination of periapical tissue. 1 , 2 Long-term outcomes include persisting inflammation and infection, resulting in abscess, sinus track formation, radiographical signs of periapical bone resorption or severe pain, with subsequent need to endodontically re-treat or remove teeth. 3 , 4 Both short-term and long-term outcomes seem to be affected by the preoperative condition of the tooth (tooth type, vitality, symptoms, periapical conditions). 4 Moreover, they might be affected by how root canal treatments are provided.

Single-visit root canal treatment attempts instrumentation, disinfection and obturation of the root canal system in one visit. In contrast, multiple-visit root canal treatment performs the instrumentation (or large parts of it) in the first and the obturation in the second visit, while the disinfection is provided in both visits via irrigation. Moreover, a disinfecting medication is placed in the canals between visits to allow further reduction of bacterial numbers. While single-visit treatment has obvious advantages over conventional multiple-visit treatment (like reduced number of visits, no need for repeated application of anaesthetics or rubberdam, no intermediary restoration); it might be disadvantageous both with regard to short-term and long-term outcomes.

A number of reviews have compared single-visit versus multiple-visit root canal treatment. 3 , 5–8 Some of these are outdated, 3 , 6 others investigate only short-term pain as outcome, 5 again others build on evidence beyond controlled trials like cohort studies or expert opinions, 7 or pooled short-term and long-term outcomes, which does not allow to weigh them against each other. 8 The present review aimed to comprehensively compare the currently available controlled trial data on short-term and long-term complications of single-visit versus multiple-visit root canal treatment. Our primary objective was to answer the question: In patients needing root canal treatment, is single-visit treatment significantly more effective than multiple-visit treatment with regard to risk of long-term failure? The secondary objective was to compare both treatments with regard to risk of short-term postoperative pain as well as the risk of flare-up. We further investigated moderators of risks using subgroup or meta-regression analysis, and assessed how statistically robust current evidence is with regard to type I or II errors using trial sequential analysis (TSA). The review should guide the conduct of further studies and help to deduct clinical recommendations.

Eligibility criteria

This systematic review (registered at PROSPERO CRD42016036386) included trials that:

Were randomised controlled trials or controlled trials without signs of selection bias (ie, treatments were not allocated according to preoperative tooth status, etc). Sensitivity analyses were performed to account for the introduced risk of bias in case of treatment allocation not being at random.

Compared single-visit with multiple-visit root canal treatment in permanent teeth with closed apices and without internal resorption, regardless of the preoperative condition (meta-regression and subgroup analyses were performed to account for different conditions).

Reported on risk of long-term complications (≥1 year after treatment), and/or risk of experiencing any short-term pain, and/or risk of short-term flare-up.

The primary outcome was the risk of long-term complications, defined as pain, infection/swelling/sinus track formation, or development, persistence or aggravation of periapical lesions or widening of the periodontal ligament, etc, ≥1 year after treatment. No standard as to how periapical lesions needed to be assessed or categorised was set, as a range of classification systems are currently used. 3 Note that against our protocol, we did not assess the need of retreatment due to long-term complications, as in most included trials it was not clearly stated, if retreatments have been performed.

The secondary outcomes were:

Risks of experiencing any short-term pain (<1 year after treatment) after obturation or after instrumentation or after both. For comparison of treatments, we considered only pain after obturation, not after instrumentation without obturation during multiple-visit treatment. To detect the largest difference between treatments, incidence of pain was extracted at the shortest recording time point after treatment. As we did not separate mild, moderate or severe pain, and even included outcome measures like having taken any pain medication in this outcome, risk of any pain does not necessarily indicate a further treatment being required. Moreover, it should be noted that different degrees of pain were pooled. This was not avoidable given the different scales used, which cannot be synthesised otherwise, but introduces additional heterogeneity.

Risks of experiencing short-term flare-up, usually defined as an acute exacerbation of an asymptomatic pulpal and/or periradicular pathosis after the initiation or continuation of root canal treatment. 9 Note that flare-up was not defined consistently across studies; some studies reported flare-up while having treated both symptomatic and asymptomatic teeth. We therefore defined flare-up as a short-term symptom (<1 year, usually directly after initiation or conclusion of root canal treatment) which led or can be assumed to lead to a further intervention (like reaccessing/reinstrumenting an incomplete treatment; completing an incision and drainage procedure, or reperforming root canal treatment).

We searched MEDLINE via PubMed, EMBASE via Ovid and Cochrane Central on 10 March 2016. Moreover, opengrey.eu was searched to identify accepted, but not published studies. There was no date restriction in our search. In addition, reference lists of identified full-texts were screened and cross-referenced. We contacted study authors if required to obtain full texts. Neither the authors nor journals were blinded to reviewers. No language restriction was set.

The applied search strategy can be found in figure 1 .

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Study flow. Database screening was performed using a four-pronged search strategy, combining four domains of the search using Boolean operators. Number of studies yielded in MEDLINE by each search domain are shown in the upper boxes; combining these boxes led to the number of results as shown for each database.

Study records

Data management.

A piloted spreadsheet was used for data extraction and management.

Selection process

Two reviewers (FS and GG) independently screened titles and then compared their findings. In case of disagreement, titles were included to obtain full texts. Full texts were assessed independently after de-duplication. Studies were included after agreement with consensus in cases of disagreement being reached through discussion.

Data collection process

Data extraction was performed independently by two reviewers (FS and GG). Disagreements were resolved through discussion.

The following items were collected: author names, year, sample, setting, tooth type, pulp vitality, preoperative pain, presence of radiographically detectable periapical lesions, instrumentation type, obturation type, irrigation, medication, intermediate restoration, number of visits, evaluation method, findings.

Outcomes and outcome measures were extracted. For studies reporting non-significant findings without any further information, this was extracted to allow including these into a sensitivity meta-analysis (see below).

Data synthesis

Meta-analysis.

The statistical unit was the tooth. Clustering was near absent in most studies. Therefore, the risk of this approach leading to artificially narrow CIs is low. 10 A continuity correction of +1 was performed in case of zero events. Random-effects meta-analysis using the DerSimonian-Laird estimator of variance was performed using Comprehensive Meta-Analysis V.2.2.64 (Biostat, Englewood, New Jersey, USA), with risk ratios (RRs) and 95% CIs as effect estimates. Fixed-effect models were used as well, but did not yield significantly different findings given the low level of heterogeneity. Unit of analysis issues were handled as described in the online supplementary appendix . Heterogeneity was assessed using Cochran's Q and I 2 statistics. 11 Funnel plot analysis and Egger test were performed to assess small study effects or publication bias. 12 , 13 RR were adjusted to check the impact of possible publication bias. 14

Supplemental material

Subgroup and meta-regression analyses.

Subgroup and meta-regression analyses were carried out to assess (1) the impact of a root canal medication being used (or not) in multiple-visit treatment, (2) pulp vitality prior treatment, (3) preoperative pain and (4) the presence of radiographically detectable periapical lesions on effect estimates. Details can be found in the online supplementary appendix .

Confidence in data

Risk of bias was assessed and classified according to Cochrane guidelines. 13 Note that against our protocol, we did not assess performance bias (blinding of operators), as this is not feasible in trials comparing single-visit versus multiple-visit treatment.

In addition, TSA was performed to assess if quantitative findings are robust, and to calculate the required information size (RIS), that is, the cumulative sample size needed to yield significant differences between treatments. 15 , 16 RIS is then adjusted for heterogeneity/diversity (DARIS). TSA additionally estimates trial sequential monitoring boundaries (TSMBs), that is, statistical thresholds for significance which are adapted depending on the so far reached sample size. Firm evidence is assumed to be reached when the Z-curve crosses the TSMB for either benefit or harm before the DARIS was reached. Effect estimates supported by only few small trials are handled stricter than those supported by large samples. In addition to such superiority/inferiority TSMBs, monitoring boundaries for futility were calculated. These indicate if further trial conduct is likely to be futile, that is, if sufficient evidence has been accrued to claim non-inferiority of treatments (which would be most relevant for this review). Further details have been reported elsewhere, 17 and can also be found in the online supplementary appendix .

Evidence for each outcome effect estimate was graded according to the GRADE working group of evidence, 18 using Grade Profiler V.3.6, and strength of recommendations deduced accordingly. 19

Results of the searches

From 817 records, 64 were screened full text. After cross-referencing 67 articles were screened and 29 included ( figure 1 ). 8 , 20–48 Excluded studies and reasons for exclusion can be found in the online supplementary appendix table S1 .

Overall, 4341 (mainly adult) patients had been treated ( table 1 ).

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Included studies

Six trials treated only teeth with vital pulps, six treated vital and non-vital teeth or did not specify vitality; the remaining trials treated non-vital teeth. Three trials clearly stated to treat only teeth with preoperative pain, 20 treated both painful and painless teeth or did not state any details on preoperative symptoms, and the remaining trials treated only teeth without preoperative symptoms. Ten trials included only teeth with periapical lesions, 13 trials did not report on radiographical status of the periapex or treated both teeth with and without lesions; the remaining trials treated only teeth without any detectable lesions.

Six trials were found to have low risk of bias (see online supplementary table S2 ), the remaining trials showed high or unclear overall risk of bias. This was mainly due to a lack of examiner blinding or allocation concealment. Two trials did not at all report on randomisation, and were treated accordingly in the performed meta-analysis. The majority of trials mentioned randomisation, but did not state how sequences were generated. Attrition was generally limited (as most trials did only assess short-term pain, see below), as was risk of selective reporting.

Risk of long-term complications

Long-term complications were investigated by 10 trials, with a total of 1257 teeth being treated. Mean follow-up was 2.3 years (range 1–5 years). All trials had used calcium hydroxide as medication in the multiple-visit group. All but two trials had high risk of bias. Risk of complications was not significantly different in single-visit versus multiple-visit treatment (RR 1.00 (95% CI 0.75 to 1.35)). Heterogeneity was low. Publication bias was not detected via Egger's test (p=0.36) or funnel plot analysis ( figure 2 A, online supplementary appendix figure S1A ).

Risk of long-term complications after single-visit versus multiple-visit root canal treatment. (A) Forest plot, with RR and 95% CIs per study and overall (black diamond) being given. Heterogeneity across studies is indicated by I² and Q. Low risk of bias and lack of random allocation of treatment is indicated by asterisks and hashtag. (B) Trial sequential analysis. The cumulative Z-score (black), that is, the accumulated level of significance, was plotted against the number of participants (N) accrued, which was compared with the DARIS. The Z-curve does not cross the conventional thresholds for superiority or inferiority (hatched grey lines). Neither the DARIS nor TSMB (grey solid lines) were reached. The information fraction was too small to draw trial sequential futility boundaries. DARIS, diversity-adjusted required information size; RR, risk ratio; TSMB, trial sequential monitoring boundary.

Preoperative conditions were not found to significantly impact on effect estimates ( table 2 ).

Meta-regression analysis

Studies which did not state to have randomly allocated treatments did not find significantly different RRs (p=0.35). By using TSA, we found neither the conventional thresholds for benefit or harm nor the TSMB for benefit, harm or futility to be reached. The sample size was far below DARIS ( figure 2 B). Given that risk of bias was serious and the number of events low (leading to imprecision), our confidence in this finding was weak.

Risk of experiencing any postoperative pain

Twenty studies used binary estimates to express risk of short-term pain. Of these, three had used a factorial design, with resulting subgroups being handled as independent studies. Three further studies used visual analogue scales and reported pain to not be significantly different; these were included in a sensitivity analyses. For the base-case analysis, a total of 3008 teeth were available and assessed. Pain had been recorded after a mean of 2 days (range 1–7 days) postoperatively. Three trials had compared pain only after instrumentation; the other studies compared pain after obturation. All but three trials showed high risk of bias.

Risk of pain was not significantly different in single-visit versus multiple-visit treatment (RR 0.99 (95% CI 0.76 to 1.30)). Heterogeneity was moderate. There was no indication for publication bias via Egger's test (p=0.46) or funnel plot analysis ( figure 3 A, online supplementary appendix figure S1B ). Preoperative conditions or the use of a calcium hydroxide instead of no root canal medication between visits had no significant impact on effect estimates ( table 2 ). Studies which did not state to have randomly allocated treatments did not find significantly different RRs compared with studies which had clearly stated randomisation (p=0.46). Including imputed studies which had only reported that differences between groups were non-significant (but had not given an effect estimate) increased the total number of assessed teeth to 3417, but did not significantly change our estimates (RR=1.00 (0.86 to 1.21)). Excluding those trials which only reported on pain after instrumentation, not obturation, also had no significant impact (RR=0.99 (0.84 to 1.17)). Using TSA, we found the conventional thresholds for benefit to be spuriously crossed, while the TSMB for benefit was not reached. Futility boundaries were not constructible due to too few data being available. The sample size was far below DARIS ( figure 3 B). Given the serious risk of bias, but only limited evidence for imprecision, this finding is supported by moderate evidence according to GRADE.

Risk of experiencing any postoperative pain after single-visit versus multiple-visit root canal treatment. (A) Forest plot. Low risk of bias and lack of random allocation of treatment is indicated by asterisks and hashtag. Studies which compared treatments in different subgroup of teeth were handled as independent studies and are indicated accordingly. (B) Trial sequential analysis. The information fraction was too small to draw trial sequential futility boundaries. DARIS, diversity-adjusted required information size; TSMB, trial sequential monitoring boundary.

Risk of flare-up

Risk of flare-up was recorded by eight studies. A total of 1110 teeth had been followed over a period of 7–10 days. All studies stated to be randomised trials, two studies showed low, the rest high risk of bias.

Risk of flare-up was significantly higher after single-visit versus multiple-visit treatment (RR 2.13 (95% CI 1.16 to 3.89)). Heterogeneity was low. There was some indication for publication bias based on funnel plot analysis, but not Egger's test (p=0.26). Adjusting the estimate accordingly increased the RR ( figure 4 A, online supplementary appendix figure S1C ). Preoperative conditions and the root canal medication had no significant impact on effect estimates ( table 2 ). Using TSA, we found the conventional thresholds for harm to be spuriously crossed, while the TSMB for harm was not reached. Futility boundaries were not constructible due to too few data being available. The sample size was far below DARIS ( figure 4 B). Given the serious risk of bias, imprecision and publication bias being present, our confidence in this finding is supported by only very weak evidence according to GRADE.

Risk of experiencing flare-up after single-visit versus multiple-visit root canal treatment. (A) Forest plot. RR and 95% CI were adjusted for publication bias using trim-and-fill (RRa). Low risk of bias and lack of random allocation of treatment is indicated by asterisks and hashtag. Studies which compared treatments in different subgroup of teeth were handled as independent studies and are indicated accordingly. (B) Trial sequential analysis. The information fraction was too small to draw trial sequential futility boundaries. DARIS, diversity-adjusted required information size; RR, risk ratio; RRa, adjusted risk ratio; TSMB, trial sequential monitoring boundary.

Even after optimal root canal disinfection via instrumentation and irrigation, bacteria usually remain within the root canal system. 49 , 50 During multiple-visit root canal treatment, an antibacterial medication like calcium hydroxide is placed in the root canals, thereby aiming to further disinfect the canals between treatment appointments, the efficacy of which remains unclear at present. 49 , 51–53 In contrast, in single-visit root canal treatment any further appointments and intracanal medications are omitted, and the root canal system obturated directly after instrumentation and irrigation, aiming to seal remaining bacteria and deprive them from both space and nutrition. 3 , 46 , 54 , 55

For risk of long-term complications, we did not find a difference between single-visit and multiple-visit endodontic treatment. This was our primary outcome as such complications oftentimes decide the fate of the tooth. 56–58 It is noteworthy that this was supported by a range of studies (ie, studies with high or low risk, small or large samples, in adults or adolescents, vital or non-vital teeth, teeth with or without periapical lesions) with relatively homogeneous findings. Only one trial found significant differences between groups (favouring single-visit treatment), 35 all others did not find one treatment significantly superior over the other.

Based on our analyses, the discussed confounders do not seem to significantly affect the relative risk of complications. Even in teeth with periapical lesions, single-visit treatment showed no significantly different risk of complications. This finding is in line with that from a previous review. 6 We want to highlight that our performed meta-regression and subgroup analyses are potentially underpowered, with high risk of type II errors. In general, our findings on the risk of complications outcome are supported by limited data, as indicated by TSA. Based on this analysis, no firm evidence on benefit, harm or futility is available (while the cumulative Z-curve never crossed any threshold for significance, once more confirming a trend towards non-difference of treatments).

The resulting evidence was graded as weak, mainly due to risk of bias of trials. Thus, a number of recommendations towards future studies need to be made: First, future trials should have higher internal validity, for example, by performing and reporting on sequence generation, by sufficiently concealing the allocation, and by blinding assessors, all to reduce the risk of selection and detection bias. We are well aware that blinding operators or patients is impossible in such trials; future reviews should reflect on this when assessing risk of bias (as we did accordingly). Second, trials should be performed in realistic (primary care) settings with sufficiently long follow-up periods, as complications are expected to occur long term. Third, trials should aim to investigate the relevance of preoperative conditions as possible confounders, as current data are insufficient to conclude on the suitability of single-visit versus multiple-visit treatment in different teeth or patients.

We also found single-visit treatment to not significantly increase the risk of short-term postoperative pain, which is in line with findings from previous reviews. 3 , 6 , 59 Pain is a relevant outcome, despite being reported only for brief periods after treatment and not being a strong predictor for success, 50 as it is directly burdening patients and could influence their attitude and behaviour towards future endodontic treatment. Our findings were again relatively consistent between trials regardless of their risk of bias, setting, patients or treated teeth. Only three studies found significant differences between groups; two in favour of single-visit treatment, 21 , 27 and one in favour of multiple-visit treatment. 30 All three were performed in non-vital teeth. It is again important to note that while we did not identify significant confounders (which is in line with previous findings), 60 our meta-regression analyses are (as discussed) of limited power. However, the overall number of treated teeth was relatively high, and while current data were4 insufficient to establish firm evidence, we expect futility boundaries of TSA to be reached if future trials confirm these findings. Given the discussed uncertainties associated with the preoperative condition (vitality, symptoms), researchers should account for these confounders when designing and evaluating future trials in the field.

We found single-visit treatment to significantly increase the risk of flare-up, which is in agreement with a previously identified increased risk of swelling after single-visit treatment. 3 It should be highlighted that our analysis for this outcome was built on only few, mainly high-risk trials, and that one particular study contributed a lot to the effect estimate given its weighting. 34 This weighting was the result of the high incidence of flare-up in this study (20% in the single-visit group), which is much higher than that in all other trials. Excluding this study from the analysis decreased the effect estimates, with no significant difference between groups remaining (RR 1.85 (0.89 to 3.86)). Given that TSA indicated that no firm evidence has been reached so far, caution is thus required when interpreting our finding regarding flare-up. Such caution is further justified as flare-ups, occurring directly after treatment as well as up to 7 days after instrumentation (or obturation), were pooled. Moreover, risk of flare-ups might be affected by further factors like patients' age, gender or systemic conditions. While patients with systemic conditions were excluded in all studies, insufficient information was available regarding gender and age distribution. Future studies should report in more detail on these aspects.

This review has a number of limitations. First, it builds only on randomised or at least controlled trials. While we see the value of practice-based long-term cohort studies (which have higher external validity and yield findings in a more relevant timeframe), we actively restricted our review on controlled studies to minimise the risk of selection bias, the impact of which can be expected to be potentially severe given that treatment decisions might be made based on the preoperative condition of the tooth. For example, dentists might be more willing to perform single-visit treatment in vital teeth, or molars might be treated in multiple visits more often due to practical reasons. This would greatly distort the true relative efficacy of both therapies.

Second, our primary outcome, complications, is a composite of different components like long-term pain, clinical signs of inflammation and infection (swelling, sinus track formation), and radiographic success (which does not need the patient to experience symptoms). For each component, a decision to re-treat or not might differ depending on who is deciding: dentists (and researchers specialising in endodontics) might see a persistent periapical lesion as an indication to re-treat even in the absence of symptoms (anticipating such symptoms to occur at some stage in the future, with poorer prognosis for retreatments). In contrast, patients might not be willing to re-treat such tooth (which might as well be justified when considering the success rates of the available retreatments and the resulting treatment costs). 58

Third, one of our secondary outcomes, the risk of experiencing any postoperative pain, does not account for the degree of pain, losing a significant amount of information. That was done as most trials reported pain using either binary scales (pain yes/no) or ordinal scales, which did not always use identical categories and pose great difficulties when pooling them (or require the definition of a certain pain threshold, which is usually arbitrary). Future studies should use continuous outcome measures like visual analogue scales, allowing to fully display the recorded information on pain. It is noteworthy that those studies which used such scales also found no significant difference of pain levels between treatments.

Last, most included trials reported only on very limited periods after treatment. While this might be acceptable for short-term pain, a follow-up of mean 2.3 years is insufficient to truly reflect ‘long-term’ complications (as is applied definition of minimum 1 year follow-up to consider a complication as long-term). This is closely related with the discussed limitations of randomised trials, which are seldom able to follow-up teeth for much longer given the high associated efforts and costs.

Future trials are thus needed to gain firm evidence whether differences in outcomes between single-visit or multiple-visit root canal treatment exist. To improve validity and comparability, these trials should aim for standardised outcome measures (eg, visual analogue scale for pain assessment; agreed definition for success/failure), long-term follow-up periods and limited risk of bias (while certain bias cannot be fully excluded). They should best be performed in representative settings and populations and report in detail on confounders of treatment success.

In conclusion and within the limitations of this review, there is insufficient evidence to rule out whether important differences in outcomes between single-visit or multiple-visit root canal treatment exist. Given the possibly increased risk of flare-up, a careful recommendation could be to prefer multiple-visit treatment in teeth where the risk if complication is increased (eg, teeth with existing periapical lesions).

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Contributors FS contributed to conception, design, data acquisition, analysis, and interpretation, drafted and critically revised the manuscript; GG contributed to conception, design, data acquisition, interpretation and critically revised the manuscript.

Funding This study was funded by the authors and their institution.

Competing interests None declared.

Provenance and peer review Not commissioned; externally peer reviewed.

Data sharing statement No additional data are available.

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• Published: 15 May 2023
• Endodontics

Does single-visit root canal treatment of permanent teeth provide more benefit than a multiple-visit approach?

• Úna M. Bryce 1 ,
• Brian M. Quinn 1 &
• David C. Edwards   ORCID: orcid.org/0000-0002-0462-7463 2  

Evidence-Based Dentistry volume  24 ,  pages 71–72 ( 2023 ) Cite this article

227 Accesses

Metrics details

• Root canal treatment

Data sources

Cochrane Oral Health’s Trials Register, Cochrane Central Register of Controlled Trials in the Cochrane Library, MEDLINE Ovid, Embase Ovid.

Study selection

Randomised controlled trials and quasi-randomised controlled trials were included. Population: Participants aged ≥ 10 with a permanent tooth possessing a completely formed apex and without resorption; Intervention: Root canal treatment (RoCT) carried out in a single visit; Comparison: RoCT carried out over multiple visits; Outcome: Primary outcome was treatment success (retention of tooth or radiographic evidence of healing), with secondary outcomes investigating post-operative symptoms (pain, swelling, sinus tract formation).

Data extraction and synthesis

Standard Cochrane methods to assess internal validity were used. The Robins 1 tool (for quasi randomised controlled trials) or risk of bias (RoB) 1 tool (for randomised controlled trials) were used to assess RoB whereby a judgement was assigned as ‘low’, ‘high’ or ‘unclear’. GRADE (GRADEpro GDT software) was used to assess certainty of evidence for each outcome. The certainty of evidence was defined as high, moderate, low or very low, having no downgrade, downgrade of one level, downgrade of two levels and downgrade of three or more levels, respectively. Of the various subgroups investigated to determine their relevance, only pretreatment conditions (vital teeth versus necrotic teeth) and endodontic technique (manual versus mechanical instrumentation) were available for subgroup analysis. The Cochrane’s test for heterogeneity and I 2 test were used to assess the variation in treatment effects. A random-effects model was used to combine risk ratio (RR) for dichotomous data and mean difference (MD) for continuous data. Sensitivity analysis was performed for each outcome, excluding studies at overall high or unclear RoB.

Forty-seven studies were included in the meta-analysis and internal validity assessment, with 5693 teeth analysed. Ten studies were found to have a low RoB, 17 with a high RoB and 20 with an unclear RoB. No evidence was identified suggesting a difference between treatment carried out in a single visit compared to a multiple visits approach for the primary outcome measure, but there was very low certainty about the findings (RR 0.46, 95% confidence interval (CI) 0.09 to 2.50; I 2 = 0%; 2 studies, 402 teeth). No evidence was identified suggesting a difference between treatment carried out in a single visit compared to multiple visits with regards to radiological failure (RR 0.93, 95% CI: 0.81 to 1.07; I 2 = 0%; 13 studies, 1505 teeth; moderate-certainty evidence), participants reporting pain up to 72 h post obturation (RR 0.97, 95% CI: 0.81 to 1.16; I 2 = 70%; 12 studies, 1329 teeth; low-certainty evidence), pain for 72 h post obturation (MD 0.26, 95% CI: −4.76 to 5.29; I 2 = 98%; 12 studies, 1258 teeth; low-certainty evidence) or pain at 1 week post obturation (RR 1.05, 95% CI: 0.67 to 1.67; I2 = 61%; 9 studies, 1139 teeth; very low-certainty evidence). Similarly, no evidence was identified to prove that there was a difference between treatment carried out in a single visit compared to multiple visits with regards to swelling or flare-up (RR 0.56 95% CI: 0.16–1.92; I 2 = 0%; 6 studies; 605 teeth; very low-certainty evidence), analgesic use (RR 1.25 95% CI: 0.75–2.09; I 2 = 36%; 6 studies, 540 teeth; very low-certainty evidence) and sinus tract or fistula presence (RR 1.00, 95% CI: 0.24–4.28; I 2 = 0%; 5 studies, 650 teeth; very low-certainty evidence). Interestingly, however, there was evidence to show that more participants reported pain after 1 week following RoCT completed in a single visit, compared to those in multiple visit groups (RR 1.55, 95% CI: 1.14–2.09; I 2 = 18%; 5 studies, 638 teeth; moderate-certainty evidence). Subgroup analysis showed there was an increase in post-treatment pain after 1 week for RoCT carried out in a single visit on vital teeth (RR 2.16, 95% CI: 1.39–3.36; I 2 = 0%; 2 studies, 316 teeth), and with the use of mechanical instrumentation (RR 1.80, 95% CI: 1.10–2.92; I 2 = 56%; 2 studies, 278 teeth).

Conclusions

The current evidence shows that RoCT carried out in a single visit is no more effective than RoCT carried out over multiple visits; after 12 months, there is no difference in pain or complications with either approach. However, single visit RoCT has been shown to have increased post-operative pain after 1 week compared to RoCT completed over multiple visits.

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Bryce, Ú.M., Quinn, B.M. & Edwards, D.C. Does single-visit root canal treatment of permanent teeth provide more benefit than a multiple-visit approach?. Evid Based Dent 24 , 71–72 (2023). https://doi.org/10.1038/s41432-023-00888-2

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DOI : https://doi.org/10.1038/s41432-023-00888-2

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Single visit root canal treatment: a prospective study

Affiliation.

• 1 Department of Restorative Dentistry, College of Medicine, University of Lagos; Department of Restorative Dentistry, Lagos University Teaching Hospital, Idi Araba, Surulere, Lagos, Nigeria.
• PMID: 24714002
• DOI: 10.4103/1119-3077.130210

Objectives: The aim was to determine the success rate of single visit root canal treatment (RCT) and thus encourage clinicians to offer this treatment option appropriately.

Materials and methods: This was a longitudinal clinical study involving all teeth of the secondary dentition except third molars in the upper and lower jaws. Teeth having irreversible pulpitis, pulp necrosis or periapical periodontitis were included in the study. RCT and obturation was done at a single visit. The patients were monitored over 6 months.

Results: Forty-five teeth were treated in 21 females and 24 males, aged 18-56 years (34.4+/-12.7). Preoperatively, pain was present in 84.4%, tenderness to percussion in 53.3%, and periapical radiolucency in 24.4% teeth. Forty percent had irreversible pulpitis and 60% had apical periodontitis. Post-operatively, pain reduced to 51.1% on day 1, 15.5% at 1 week, and 0% for the rest of the period. Tenderness to percussion reduced to 15.6% at 1 week and 0% by 1 month. Periapical radiolucency reduced to 9.5% at 6 months. Favorable outcome of 33.3% was recorded on day 1 and increased to 90.5% at 6 months. Six months success rate for teeth which had irreversible pulpitis was 100% and 83.3% for apical periodontitis. The mean time needed to complete a single visit RCT ranged from 77 min for a tooth having one canal to 132 min for one having four canals.

Conclusion: Single visit RCT is a viable treatment option for teeth having irreversible pulpitis or apical periodontitis irrespective of tooth type or number of canals.

Clinical significance: A lot of patients are lost to follow-up visits for teeth requiring RCT once the pulp is extirpated at the first visit due to cessation of pain, subsequently leading to treatment failure. Single visit endodontics eliminates the need for follow-up visits and improves treatment prognosis.

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Single- Vs Multiple-Visit Root Canal Therapy

Treatment selection requires consideration of factors beyond prognosis

Shraya Sharma | Brooke Blicher, DMD | Rebekah Lucier Pryles, DMD | Jarshen Lin, DDS

The number of treatment visits required to perform root canal therapy (RCT) has been hotly debated since the establishment of endodontics as a specialty. Single-visit RCT involves cleaning, shaping, and obturation during a single treatment session. Alternatively, multiple-visit treatment includes placement of a short-term medicament, such as calcium hydroxide, for the time between the cleaning and shaping appointment and the obturation appointment. Many practitioners utilize outcomes data to justify their treatment decisions; however, the research comparing single- and multiple-visit RCT has consistently demonstrated equivalent outcomes for both treatment approaches. 1 Although convenience clearly favors single-appointment therapy, patients generally prefer the approach that their provider recommends. 2 As with any area of controversy regarding treatment selection, clinicians must understand the utility of each approach as well as its relative risks and benefits. The selection of either single- or multiple-visit RCT necessitates that practitioners consider factors beyond prognosis, including the presence of preoperative pain, infection status, pulpal and periapical diagnoses, case complexity, and any restorative concerns, to provide a framework for clinical decision-making (Figure 1). 3,4 These factors should be considered together and not individually because significant interrelationships can exist among them. 3,4 This article reviews some of the factors beyond outcomes that practitioners should consider in order to develop evidence-based justifications for both single- and multiple-visit RCT. Following the evidence as it relates to these factors allows practitioners to integrate clinical expertise with the most current findings to effectively address patients' individual needs.

Preoperative Pain

Assessment of preoperative pain is a critical factor in the selection of either single- or multiple-visit RCT. For patients who are experiencing severe pain, with or without swelling, it may be necessary to avoid lengthy appointments, particularly because preoperative pain is significantly associated with postoperative pain. 5 Therefore, in such cases, treatment should be aimed at pain alleviation and limited to access and instrumentation during the first visit, while deferring obturation to a subsequent appointment. Understanding the length of time that a patient can comfortably tolerate during a visit is central to this decision. Furthermore, providing multiple-visit therapy to patients in significant pain allows clinicians to assess symptom resolution during the second appointment. Ensuring symptom resolution demonstrates the practitioner's concern for his or her patients-a "soft skill" that goes beyond the evidence-based reasoning for providing multiple-visit care. A systematic review revealed that although the radiologic success rates of single- and multiple-visit RCT were similar, analgesic use was significantly less common among patients who underwent the latter approach. 6

Infection Status

When selecting between single- and multiple-visit therapy, consideration must be given to any clinical findings related to infection, including swelling and the presence of purulent drainage from the root canal spaces or sinus tracts. Multiple-appointment RCT allows providers to assess the effect of treatment on infected tissues and ensure symptom resolution prior to obturation of the root canal space. 7

Pulpal and Periapical Diagnoses

Pulpal and periapical diagnoses can be challenging to incorporate into the decision-making process. Consensus is currently lacking regarding the impact of these diagnoses on clinical outcomes. However, establishing pulpal and periapical diagnoses can significantly assist a clinician in deciding between single- and multiple-visit endodontics. For vital teeth, including teeth diagnosed with pulpitis with or without apical periodontitis, a single-visit approach may be appropriate. 3,8 Investigators postulate that vital teeth often have a superficially infected pulp and a relatively uncontaminated canal system; thus, a single-visit approach can allow for greater efficiency in care. 8 For teeth diagnosed with pulp necrosis, some investigators suggest that the use of an intracanal medication between appointments leads to greater disinfection of the canals, whereas others have found no significant difference in the success rates between the two treatment approaches. 7,9 However, for symptomatic non-vital teeth and asymptomatic non-vital teeth (with apical periodontitis), multiple-appointment treatment is often recommended (Figure 2 through Figure 4). 3,4 In previously treated teeth, a two-visit approach with calcium hydroxide as the intracanal medicament has been shown to be significantly more effective at reducing postoperative pain and flare-ups. 10

Case Complexity

The complexity of the presenting case may dictate the choice of a single- or multiple-visit approach to therapy. The American Association of Endodontists' "Endodontic Case Difficulty Assessment Form" can help practitioners determine a case's complexity. 11 Complicating factors are not only limited to canal calcifications and root curvatures, but also include the medical history, the patient's disposition and level of compliance, local anesthesia history, emergency conditions, radiographic difficulties, tooth location in the arch, isolation concerns, and a history of trauma. 11 Examples of complicating factors that can be found in the medical history include the use of immunosuppressive medications, poorly controlled diabetes, recent myocardial infarction, or an American Society of Anesthesiology physical status classification of class III or above. 12

A history of complications related to local anesthesia can render cases more challenging and may necessitate multiple-visit therapy. In particular, providing effective pulpal anesthesia for a tooth diagnosed with symptomatic irreversible pulpitis (ie, a "hot" tooth) can be especially difficult and may require supplemental anesthesia, such as a periodontal ligament, intrapulpal, or intraosseous injection. 13 Although effective, the duration of pulpal anesthesia in such clinical scenarios can be reduced to approximately 30 to 45 minutes. 13 In addition to a potentially shortened duration of anesthesia, the amount of time required to sufficiently anesthetize a tooth with symptomatic irreversible pulpitis can significantly increase chairtime during treatment. Thus, in cases with such concerns, consideration should be given to performing multiple-visit RCT.

Similar to concerns regarding the medical history and a history of anesthesia complications, the presence and degree of clinical symptoms indicating an endodontic emergency are complicating factors that should also be evaluated when selecting between single- or multiple-appointment therapy. In cases with moderate or severe swelling or pain, a multiple-visit approach allows for the evaluation of symptom resolution at the second visit. 6 Challenges to obtaining and interpreting radiographs can also hinder the delivery of therapy in a single session. In these cases, anatomical variations, such as the presence of an elevated floor of mouth, tori, narrow or low palatal vault, or superimposed anatomical structures, should be taken into consideration when selecting the treatment modality. 11

Beyond radiologic challenges, the location of a tooth in the arch can significantly impact case complexity. Although anterior and bicuspid teeth, as well as teeth with a slight inclination or rotation (ie, < 10°), may allow for single-visit therapy, molars and teeth presenting with a more extensive inclination or rotation (ie, > 30°) offer unique challenges to access preparation that can slow comprehensive treatment and require two or more sessions. Finally, a history of trauma can be a critical factor in deciding the appropriate number of visits for a patient. Cases presenting with minimal difficulty, such as uncomplicated crown fractures, may be addressed in a single-visit session, given that there are no other complications. However, challenging cases, such as those involving avulsion, alveolar fracture, or luxation, may be best addressed through a multiple-appointment approach that allows for a thorough follow-up of symptoms, tooth prognosis, and response to therapy. 11 All things considered, when compared with more complex cases, less complicated cases may be more readily treated in a single visit.

Restorative Concerns

Restorative concerns, such as anterior esthetics, issues related to isolation and sealing, and pre-prosthetic factors, can also impact the selection of either single- or multiple-visit therapy. Complicated crown fractures of anterior and bicuspid teeth and horizontal crown fractures at the gum line of anterior teeth commonly involve esthetic considerations. In cases with such concerns, barring other complicating factors, consideration must be given to single-visit RCT to facilitate the rapid placement of a temporary crown in order to restore form, function, and esthetics. 14

Achieving effective isolation and then subsequently sealing the canal system to prevent reinfection are essential components of successful RCT. In most cases, both can be achieved. However, for teeth with subgingival breakdown, missing coronal walls, or full coverage restorations with decay below the margins, adequate isolation and sealing can be particularly challenging. When teeth present with these findings, consideration should be given to single-visit therapy in order to reduce the chances of interappointment contamination and flare-up. 14

The purview of pre-prosthetic concerns includes teeth that require RCT for restorative purposes, rather than for the debridement of pathologic pulp tissue or pulp exposures. Several cases fall within this category, including teeth needed for overdenture abutments, teeth that cannot retain a restoration due to severe coronal breakdown, mandibular anterior teeth that are reduced for full jacket crowns, and teeth that require preparation that would result in pulp exposure for a specifically designed restoration. In such cases, a single-visit approach is encouraged to accelerate the process of restoring form, function, and esthetics of the involved teeth. 14 A summary of the indications for which single- or multiple-visit therapy may be appropriate is presented in Figure 5.

Time and time again, the endodontic literature demonstrates that the outcomes for single-visit treatment and multiple-visit treatment are equivalent. Given these findings, decisions to pursue either approach to treatment must be informed by factors that go beyond prognosis alone. By considering preoperative pain, infection status, pulpal and periapical diagnoses, case complexity, and restorative concerns, clinicians can select the treatment modality that is most appropriate to treat their patients' endodontic needs.

About the Authors

Shraya Sharma DMD Candidate, Class of 2020 Harvard School of Dental Medicine Boston, Massachusetts

Rebekah Lucier Pryles, DMD Upper Valley Endodontics White River Junction, Vermont Assistant Clinical Professor Department of Endodontics Tufts University School of Dental Medicine Boston, Massachusetts

Brooke Blicher, DMD Upper Valley Endodontics White River Junction, Vermont Assistant Clinical Professor Department of Endodontics Tufts University School of Dental Medicine Boston, Massachusetts Clinical Instructor Department of Restorative Dentistry and Biomaterials Science Harvard School of Dental Medicine Boston, Massachusetts

Jarshen Lin, DDS Director of Predoctoral Endodontics Department of Restorative Dentistry and Biomaterials Science Harvard School of Dental Medicine Boston, Massachusetts Clinical Associate Department of Oral and Maxillofacial Surgery Massachusetts General Hospital Boston, Massachusetts

1. Su Y, Wang C, Ye L. Healing rate and post-obturation pain of single- versus multiple-visit endodontic treatment for infected root canals: a systematic review. J Endod . 2011;37(2):125-132.

2. Vela KC, Walton RE, Trope M, et al. Patient preferences regarding 1-visit versus 2-visit root canal therapy. J Endod . 2012;38(10):1322-1325.

3. Ahmed F, Thosar N, Baliga MS, et al. Single visit endodontic therapy: a review. Austin J Dent . 2016;3(2):1035-1039.

4. Swetah CSV, Ranjan M. Single visit vs. multiple visits for endodontic treatment: a review. Int J of Sci Dev and Res . 2017;2(10):23-27.

5. Sadaf D, Ahmad MZ. Factors associated with postoperative pain in endodontic therapy. Int J Biomed Sci . 2014;10(4):243-247.

6. Figini L, Lodi G, Gorni F, et al. Single versus multiple visits for endodontic treatment of permanent teeth:a Cochrane systematic review. J Endod . 2008;34(9):1041-1047.

7. Cohen S, Hargreaves, K. Cohen's Pathways of the Pulp. 10th ed. St. Louis, MI: Mosby; 2011.

8. Mohammadi Z, Farhad A, Tabrizizadeh M. One-visit versus multiple-visit endodontic therapy-a review. Int Dent J . 2006;56(5):289-293.

9. Sjogren U, Hagglund B, Sundqvist G, et al. Factors affecting the long-term results of endodontic treatment. J Endod . 1990;16(10):498-504.

10. Yoldas O, Topuz A, Isçi AS, et al. Postoperative pain after endodontic retreatment: single- versus two-visit treatment. Oral Surg Oral Med Oral Pathol Oral Radiol Endod . 2004;98(4):483-487.

11. American Association of Endodontists. AAE Endodontic Case Difficulty Assessment Form and Guidelines. https://www.aae.org/specialty/wp-content/ uploads/sites/2/2017/06/2006casedifficultyassessmentformb_edited2010.pdf. Accessed July 30, 2018.

12. Rajeswari K, Kandaswamy D, Karthick S. Endo-dontic management of patients with systemic complications. J Pharm Bigoallied Sci . 2016;8(Suppl 1):S32-S35.

13. Nusstein JM, Reader A, Drum M. Local anesthesia strategies for the patient with a "hot" tooth. Dent Clin North Am . 2010;54(2):237-247.

14. Singla R, Marwah N, Dutta S. Single visit versus multiple visit root canal therapy. International Journal of Clinical Pediatric Dentistry . 2008;1(1):17-24.

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May 30, 2024

Gilead Provides Update on Phase 3 TROPiCS-04 Study

FOSTER CITY, Calif.--(BUSINESS WIRE)-- Gilead Sciences, Inc. (Nasdaq: GILD) today announced topline results from the confirmatory Phase 3 TROPiCS-04 study in locally advanced or metastatic urothelial cancer (mUC). The TROPiCS-04 study evaluated Trodelvy ® (sacituzumab govitecan-hziy; SG) vs. single-agent chemotherapy (treatment of physicians’ choice, TPC) in patients with mUC who have previously received platinum-containing chemotherapy and anti-PD-(L)1 therapy.

The study did not meet the primary endpoint of overall survival (OS) in the intention-to-treat (ITT) population. A numerical improvement in OS favoring Trodelvy was observed, and trends in improvement for select pre-specified subgroups and secondary endpoints of progression-free survival (PFS) and overall response rate (ORR) were also shown. The pre-specified subgroup analyses were not alpha-controlled for formal statistical testing. These data will be presented at an upcoming medical meeting.

In the overall study population, there was a higher number of deaths due to adverse events with Trodelvy compared to TPC, which were primarily observed early in treatment and related to neutropenic complications, including infection. Gilead will further investigate these data, and is working to reiterate to treating physicians the importance of granulocyte-colony stimulating factor (G-CSF) use for the prevention of neutropenic complications. Trodelvy has a Boxed Warning for severe or life-threatening neutropenia; please see below for Important Safety Information.

There are no changes to the known safety profile of Trodelvy for the approved breast cancer indications or other investigational uses. To date, the Trodelvy safety profile is generally well-tolerated and consistent with use in over 40,000 patients across Trodelvy’s approved indications and in clinical trials.

Gilead is continuing to analyze the data and will discuss the results and next steps with the FDA. In the U.S., Trodelvy has an accelerated approval indication for patients with locally advanced or metastatic urothelial cancer (mUC) who have previously received a platinum-containing chemotherapy and anti-PD-(L)1 therapy. This indication is approved under accelerated approval based on tumor response rate and duration of response. Continued approval for this indication may be contingent upon verification and description of clinical benefit in confirmatory trials, including the TROPiCS-04 study.

Metastatic UC is an aggressive disease which most commonly affects older patients with concurrent medical morbidities and additional changes related to the aging process. Despite recent advances, survival rates remain poor with only 8% of patients living beyond five years after diagnosis. These results may in part reflect the difficulty of treating patients with mUC who have previously received platinum-containing chemotherapy and checkpoint inhibitor therapy. There is an urgent need for new treatment options to help improve long-term outcomes.

Gilead would like to thank the patients, families, investigators, and advocates who contributed to this important research. We remain committed to advancing care to address the unmet needs for the bladder cancer community.

Trodelvy is the first approved Trop-2-directed antibody-drug conjugate (ADC), which has demonstrated meaningful survival advantages in two different types of metastatic breast cancers. There are more than 20 ongoing clinical trials for Trodelvy.

Please see below for the approved U.S. Indication and additional Important Safety Information.

About Metastatic Urothelial Cancer

Bladder cancer is one of the most common cancers worldwide, with more than 1.6 million people living with the disease and urothelial cancer (UC) accounting for 90% of these cases. Metastatic bladder cancer is an aggressive disease and survival rates remain poor, with only 8% of patients living beyond five years after diagnosis. Despite recent advances, less than 20% of patients with metastatic bladder cancer go on to receive second-line therapy. There is an urgent need for new treatment options for patients with mUC who have progressed on available therapies to help improve long-term outcomes.

About the TROPiCS-04 Study

The TROPiCS-04 study is an open-label, global, multi-center, randomized Phase 3 study that evaluated Trodelvy vs. single-agent chemotherapy (treatment of physicians’ choice, TPC) in patients with locally advanced or mUC who received platinum-containing chemotherapy and checkpoint inhibitor therapy. The study enrolled 711 patients randomized 1:1 to receive either Trodelvy or one of three TPC chemotherapeutic standard of care (SOC) options: paclitaxel, docetaxel, or vinflunine. The primary endpoint was OS. Secondary endpoints included progression-free survival (PFS), objective response rate (ORR), clinical benefit rate (CBR) and duration of objective tumor response (DoR) as assessed by investigator per Response Evaluation Criteria in Solid Tumors (RECIST 1.1) and blinded independent central review (BICR). Further study details are available on clinicaltrials.gov ( NCT04527991 ).

About Trodelvy

Trodelvy ® (sacituzumab govitecan-hziy) is a first-in-class Trop-2-directed antibody-drug conjugate. Trop-2 is a cell surface antigen highly expressed in multiple tumor types, including in more than 90% of breast, bladder and lung cancers. Trodelvy is intentionally designed with a proprietary hydrolyzable linker attached to SN-38, a topoisomerase I inhibitor payload. This unique combination delivers potent activity to both Trop-2 expressing cells and the tumor microenvironment through a bystander effect.

Trodelvy is approved in almost 50 countries, with multiple additional regulatory reviews underway worldwide, for the treatment of adult patients with unresectable locally advanced or metastatic triple-negative breast cancer (TNBC) who have received two or more prior systemic therapies, at least one of them for metastatic disease.

Trodelvy also has multiple global approvals for certain patients with pre-treated HR+/HER2- metastatic breast cancer, including in Australia, Brazil, Canada, the European Union, Israel, United Arab Emirates and the United States. In the U.S., Trodelvy has an accelerated approval for treatment of certain patients with second-line or later metastatic urothelial cancer; see below for full indication statements.

Trodelvy is being explored for potential investigational use in other TNBC, HR+/HER2- and metastatic UC populations, as well as a range of tumor types where Trop-2 is highly expressed, including metastatic non-small cell lung cancer (NSCLC), head and neck cancer, gynecological cancer, and gastrointestinal cancers.

U.S. Indications for Trodelvy

In the United States, Trodelvy is indicated for the treatment of adult patients with:

• Unresectable locally advanced or metastatic triple-negative breast cancer (mTNBC) who have received two or more prior systemic therapies, at least one of them for metastatic disease.
• Unresectable locally advanced or metastatic hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative (IHC 0, IHC 1+ or IHC 2+/ISH–) breast cancer who have received endocrine-based therapy and at least two additional systemic therapies in the metastatic setting.
• Locally advanced or metastatic urothelial cancer (mUC) who have previously received a platinum-containing chemotherapy and either programmed death receptor-1 (PD-1) or programmed death-ligand 1 (PD-L1) inhibitor. This indication is approved under accelerated approval based on tumor response rate and duration of response. Continued approval for this indication may be contingent upon verification and description of clinical benefit in confirmatory trials.

U.S. Important Safety Information for Trodelvy

BOXED WARNING: NEUTROPENIA AND DIARRHEA

• Severe or life-threatening neutropenia may occur. Withhold Trodelvy for absolute neutrophil count below 1500/mm 3 or neutropenic fever. Monitor blood cell counts periodically during treatment. Consider G-CSF for secondary prophylaxis. Initiate anti-infective treatment in patients with febrile neutropenia without delay.
• Severe diarrhea may occur. Monitor patients with diarrhea and give fluid and electrolytes as needed. At the onset of diarrhea, evaluate for infectious causes and, if negative, promptly initiate loperamide. If severe diarrhea occurs, withhold Trodelvy until resolved to ≤Grade 1 and reduce subsequent doses.

CONTRAINDICATIONS

• Severe hypersensitivity reaction to Trodelvy.

WARNINGS AND PRECAUTIONS

Neutropenia: Severe, life-threatening, or fatal neutropenia can occur and may require dose modification. Neutropenia occurred in 64% of patients treated with Trodelvy. Grade 3-4 neutropenia occurred in 49% of patients. Febrile neutropenia occurred in 6%. Neutropenic colitis occurred in 1.4%. Withhold Trodelvy for absolute neutrophil count below 1500/mm 3 on Day 1 of any cycle or neutrophil count below 1000/mm 3 on Day 8 of any cycle. Withhold Trodelvy for neutropenic fever. Administer G-CSF as clinically indicated or indicated in Table 1 of USPI.

Diarrhea: Diarrhea occurred in 64% of all patients treated with Trodelvy. Grade 3-4 diarrhea occurred in 11% of patients. One patient had intestinal perforation following diarrhea. Diarrhea that led to dehydration and subsequent acute kidney injury occurred in 0.7% of all patients. Withhold Trodelvy for Grade 3-4 diarrhea and resume when resolved to ≤Grade 1. At onset, evaluate for infectious causes and if negative, promptly initiate loperamide, 4 mg initially followed by 2 mg with every episode of diarrhea for a maximum of 16 mg daily. Discontinue loperamide 12 hours after diarrhea resolves. Additional supportive measures (e.g., fluid and electrolyte substitution) may also be employed as clinically indicated. Patients who exhibit an excessive cholinergic response to treatment can receive appropriate premedication (e.g., atropine) for subsequent treatments.

Hypersensitivity and Infusion-Related Reactions: Serious hypersensitivity reactions including life-threatening anaphylactic reactions have occurred with Trodelvy. Severe signs and symptoms included cardiac arrest, hypotension, wheezing, angioedema, swelling, pneumonitis, and skin reactions. Hypersensitivity reactions within 24 hours of dosing occurred in 35% of patients. Grade 3-4 hypersensitivity occurred in 2% of patients. The incidence of hypersensitivity reactions leading to permanent discontinuation of Trodelvy was 0.2%. The incidence of anaphylactic reactions was 0.2%. Pre-infusion medication is recommended. Have medications and emergency equipment to treat such reactions available for immediate use. Observe patients closely for hypersensitivity and infusion-related reactions during each infusion and for at least 30 minutes after completion of each infusion. Permanently discontinue Trodelvy for Grade 4 infusion-related reactions.

Nausea and Vomiting: Nausea occurred in 64% of all patients treated with Trodelvy and Grade 3-4 nausea occurred in 3% of these patients. Vomiting occurred in 35% of patients and Grade 3-4 vomiting occurred in 2% of these patients. Premedicate with a two or three drug combination regimen (e.g., dexamethasone with either a 5-HT3 receptor antagonist or an NK 1 receptor antagonist as well as other drugs as indicated) for prevention of chemotherapy-induced nausea and vomiting (CINV). Withhold Trodelvy doses for Grade 3 nausea or Grade 3-4 vomiting and resume with additional supportive measures when resolved to Grade ≤1 . Additional antiemetics and other supportive measures may also be employed as clinically indicated. All patients should be given take-home medications with clear instructions for prevention and treatment of nausea and vomiting.

Increased Risk of Adverse Reactions in Patients with Reduced UGT1A1 Activity: Patients homozygous for the uridine diphosphate-glucuronosyl transferase 1A1 (UGT1A1)*28 allele are at increased risk for neutropenia, febrile neutropenia, and anemia and may be at increased risk for other adverse reactions with Trodelvy. The incidence of Grade 3-4 neutropenia was 58% in patients homozygous for the UGT1A1*28, 49% in patients heterozygous for the UGT1A1*28 allele, and 43% in patients homozygous for the wild-type allele. The incidence of Grade 3-4 anemia was 21% in patients homozygous for the UGT1A1*28 allele, 10% in patients heterozygous for the UGT1A1*28 allele, and 9% in patients homozygous for the wild-type allele. Closely monitor patients with known reduced UGT1A1 activity for adverse reactions. Withhold or permanently discontinue Trodelvy based on clinical assessment of the onset, duration and severity of the observed adverse reactions in patients with evidence of acute early-onset or unusually severe adverse reactions, which may indicate reduced UGT1A1 function.

Embryo-Fetal Toxicity: Based on its mechanism of action, Trodelvy can cause teratogenicity and/or embryo-fetal lethality when administered to a pregnant woman. Trodelvy contains a genotoxic component, SN-38, and targets rapidly dividing cells. Advise pregnant women and females of reproductive potential of the potential risk to a fetus. Advise females of reproductive potential to use effective contraception during treatment with Trodelvy and for 6 months after the last dose. Advise male patients with female partners of reproductive potential to use effective contraception during treatment with Trodelvy and for 3 months after the last dose.

ADVERSE REACTIONS

In the pooled safety population, the most common (≥ 25%) adverse reactions including laboratory abnormalities were decreased leukocyte count (84%), decreased neutrophil count (75%), decreased hemoglobin (69%), diarrhea (64%), nausea (64%), decreased lymphocyte count (63%), fatigue (51%), alopecia (45%), constipation (37%), increased glucose (37%), decreased albumin (35%), vomiting (35%), decreased appetite (30%), decreased creatinine clearance (28%), increased alkaline phosphatase (28%), decreased magnesium (27%), decreased potassium (26%), and decreased sodium (26%).

In the ASCENT study (locally advanced or metastatic triple-negative breast cancer), the most common adverse reactions (incidence ≥25%) were fatigue, diarrhea, nausea, alopecia, constipation, vomiting, abdominal pain, and decreased appetite. The most frequent serious adverse reactions (SAR) (>1%) were neutropenia (7%), diarrhea (4%), and pneumonia (3%). SAR were reported in 27% of patients, and 5% discontinued therapy due to adverse reactions. The most common Grade 3-4 lab abnormalities (incidence ≥25%) in the ASCENT study were reduced neutrophils, leukocytes, and lymphocytes.

In the TROPiCS-02 study (locally advanced or metastatic HR-positive, HER2-negative breast cancer), the most common adverse reactions (incidence ≥25%) were diarrhea, fatigue, nausea, alopecia, and constipation. The most frequent serious adverse reactions (SAR) (>1%) were diarrhea (5%), febrile neutropenia (4%), neutropenia (3%), abdominal pain, colitis, neutropenic colitis, pneumonia, and vomiting (each 2%). SAR were reported in 28% of patients, and 6% discontinued therapy due to adverse reactions. The most common Grade 3-4 lab abnormalities (incidence ≥25%) in the TROPiCS-02 study were reduced neutrophils and leukocytes.

In the TROPHY study (locally advanced or metastatic urothelial cancer), the most common adverse reactions (incidence ≥25%) were diarrhea, fatigue, nausea, any infection, alopecia, decreased appetite, constipation, vomiting, rash, and abdominal pain. The most frequent serious adverse reactions (SAR) (≥5%) were infection (18%), neutropenia (12%, including febrile neutropenia in 10%), acute kidney injury (6%), urinary tract infection (6%), and sepsis or bacteremia (5%). SAR were reported in 44% of patients, and 10% discontinued due to adverse reactions. The most common Grade 3-4 lab abnormalities (incidence ≥25%) in the TROPHY study were reduced neutrophils, leukocytes, and lymphocytes.

DRUG INTERACTIONS

UGT1A1 Inhibitors: Concomitant administration of Trodelvy with inhibitors of UGT1A1 may increase the incidence of adverse reactions due to potential increase in systemic exposure to SN-38. Avoid administering UGT1A1 inhibitors with Trodelvy.

UGT1A1 Inducers: Exposure to SN-38 may be reduced in patients concomitantly receiving UGT1A1 enzyme inducers. Avoid administering UGT1A1 inducers with Trodelvy.

Please see full Prescribing Information , including BOXED WARNING.

About Gilead Sciences

Gilead Sciences, Inc. is a biopharmaceutical company that has pursued and achieved breakthroughs in medicine for more than three decades, with the goal of creating a healthier world for all people. The company is committed to advancing innovative medicines to prevent and treat life-threatening diseases, including HIV, viral hepatitis, COVID-19, and cancer. Gilead operates in more than 35 countries worldwide, with headquarters in Foster City, California.

Forward-Looking Statements

This press release includes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 that are subject to risks, uncertainties and other factors, including Gilead’s ability to initiate, progress or complete clinical trials within currently anticipated timelines or at all, and the possibility of unfavorable results from ongoing or additional clinical trials, including those involving Trodelvy; uncertainties relating to regulatory applications and related filing and approval timelines, including pending or potential applications for Trodelvy for the treatment of metastatic and other TNBC, HR+/HER2- metastatic breast cancer, mUC, metastatic NSCLC, head and neck cancer, gynecological cancer and gastrointestinal cancer; Gilead’s ability to receive regulatory approvals for programs and/or indications that are currently under evaluation in a timely manner or at all, including the risk that the FDA may not grant full approval or may withdraw its accelerated approval for Trodelvy for the treatment of locally advanced or metastatic urothelial cancer (mUC), and the risk that any such approvals may be subject to significant limitations on use and is subject to, withdrawal or other adverse actions by the applicable regulatory authority; the possibility that Gilead may make a strategic decision to discontinue development of programs for indications that are currently under evaluation, including Trodelvy for treatment of mUC, and as a result, these programs may never be or cease to be commercialized for such indications; and any assumptions underlying any of the foregoing. These and other risks, uncertainties and other factors are described in detail in Gilead’s Quarterly Report on Form 10-Q for the quarter ended March 31, 2024, as filed with the U.S. Securities and Exchange Commission. These risks, uncertainties and other factors could cause actual results to differ materially from those referred to in the forward-looking statements. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. The reader is cautioned that any such forward-looking statements are not guarantees of future performance and involve risks and uncertainties, and is cautioned not to place undue reliance on these forward-looking statements. All forward-looking statements are based on information currently available to Gilead, and Gilead assumes no obligation and disclaims any intent to update any such forward-looking statements.

U.S. Prescribing Information for Trodelvy including BOXED WARNING , is available at www.gilead.com .

Trodelvy, Gilead and the Gilead logo are trademarks of Gilead Sciences, Inc., or its related companies.

For more information about Gilead, please visit the company’s website at www.gilead.com or call Gilead Public Affairs at 1-800-GILEAD-5 or 1-650-574-3000.

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• Int J Clin Pediatr Dent
• v.1(1); Sep-Dec 2008

Single Visit versus Multiple Visit Root Canal Therapy

Rajesh singla.

1 Postgraduate Student, Govt. Dental College, Rohtak, India

Nikhil Marwah

2 Asst. Professor, Govt. Dental College, Rohtak, India

Samir Dutta

3 Sr. Professor and Head, Govt. Dental College, Rohtak, India

Aim: The purpose of this study was to determine clinical success rate of single visit verses multiple visit root canal treatment in cariously exposed vital primary molars.

Material& methods: 40 children in age group of 4 to 7 years were divided equally into two treatment groups and recall visits were carried out after one week, one month and three months and six months.

Results: Statistically no significant difference was found.

Conclusion: Multiple visit and single visit root canal treatment demonstrated almost equal success but most important aspect for success in pulpectomy cases is the indication of each case and then its subsequent treatment, be it multiple or single visit root canal treatment.

INTRODUCTION

In general, attitudes and concepts concerning proven, time tested treatment procedures are very slow and difficult to change in the health professions. We are often reluctant to abandon predictable treatment procedures because we fear a change to some new treatment modality may not result in the some outcome or take of success we have come to expect but as new data that may alter a pre-existing old concepts may have to expand in order to accommodate this new information. Research studies into intracanal preparation culturing, intracanal medicaments, and root canal filling materials and techniques have led us to expand and in some cases, completely alter our concepts concerning the clinical conduct of our practice in these areas.

Historically root canal treatment was performed in multiple visits mainly to ensure sterility of root canal system prior to obturation. As complete sterilization was not possible with biomechanical preparation and irrigation, intracanal medicaments were used to ensure the complete eradication of bacteria. In addition to killing bacteria, these agents, primarily phenolic compounds, were also highly irritating to the periradicular tissues. 1 , 2 Overzealous use of these medicaments led to postoperative complications that were erroneously identified as persistent periradicular infections. Hence, this led to the inappropriate and excessive use of antibiotics to control infections. Ultimately the deleterious effects of these medicaments were identified 1 and their routine clinical use was discontinued. This led to one of the two course of treatment either treat the root canal in one visit or seek an intracanal medicament that does not injure the periradicular tissues.

Those who believe that successful root canal treatment can be completed in one visit have rationale in literature. Studies concerning postoperative pain 3 - 6 as well as healing rates 7 - 9 shows the treatment outcome to be similar whether completed in one or multiple visits. In addition to this, treatment in one visit offers many advantages. This decreases the number of operative procedure including additional anesthesia, gingival trauma from rubber dam application as well as eliminating the risk of inter appointment leakage through temporary restoration. It is less time consuming resulting in less cost to the patients.

Proponents of multiple visit procedures contend that antimicrobial property of inter appointment calcium hydroxide placement is required to ensure successful perradicular healing, 10 - 12 although predictable levels of bacterial reduction via refined cleaning and shaping techniques is one appointment may negate this need. 13

Furthermore, when flare-ups occur during multiple-visit procedures, they can be addressed prior to obturation. 7 This is not an option in a single-visit treatment regimen. When flare-ups occur, non-surgical re-treatment or surgical intervention is usually necessary.

The purpose of the study was to determine clinical success rate of single visit verses multiple visit root canal treatment in cariously exposed vital primary molars.

INDICATIONS FOR SINGLE-VISIT TREATMENT

Isolation and sealing problems.

One of the main objectives when endodontics is performed in multiple visits is the difficulty of effectively sealing off the root canal system from the oral cavity between visits. Although this aim may be easily obtained in most cases, there are certain situations in which a one-visit procedure can be used to eliminate the potential problem of interappointment contamination and/or flare-up.

Teeth with subgingival breakdown; coronal walls missing; and with full coverage that have decay below the margins of their finished restorations would all fall into this category. 14

Anterior Esthetic Problems

Cases falling into this category would be maxillary anterior teeth involved in trauma that has resulted in a horizontal fracture of the crown at the gum line. These cases are probably the most frequently treated teeth in one-visit. Therefore, isolation and sealing problems are solved and an esthetic temporary crown can be placed rapidly and retained by securing the crown to a temporary post placed into the space left in the root canal of the treated tooth. 14

Restorative Considerations

Cases that fall into this category require endodontic treatment for restorative reasons and not because they have pathologic pulp tissue that must be removed or because of pulp exposures. Examples would include: teeth to be used as overdenture abutments; mandibular anterior teeth to be cut down for full jacket crowns; teeth with severe coronal breakdown that cannot possibly retain a restoration because of the loss of tooth structure; and teeth that require preparation that would result in pulp exposure in order to get them into a certain desired alignment for the construction of a specifically designed restoration. 14

Vital Pulp Exposure and Symptomatic Pulpitis

Teeth containing vital pulps that fit into this category are those with pulp exposures caused by trauma, caries, or mechanical reasons and teeth that exhibit clinical symptoms to heat or cold stimuli but not percussion. 14

MATERIAL AND METHODS

A sample of 40 children in age group of 4 to 7 years visiting to Department of Pedodontic for dental treatment at Govt. Dental College, Rohtak, were included in this study after receiving permission from their parents. 40 teeth which were cariously exposed showing no sign of abnormal mobility, swelling or sinus tract formation and requiring pulpectomy were selected for study.

These were randomly into two equal groups.

Group I: Single visit treatment group

Group II: Multiple visit treatment group

Endodontic therapy in each case was carried out under local anesthesia and rubber dam isolation. The pulp was extirpated and diagnostic radiographs were made to determine working length. Biomechanical preparations were done using 2.5% sodium hypochlorite as root canal irrigant.

In single visit group, after biomechanical preparation, root canals were dried using absorbent paper points and root canals were filled with thick mix of zinc oxide eugenol using engine driven lentulo spirals. Access cavities were sealed with silver amalgam/glass ionomer cement after obturation.

In multiple visit group, access was gained and after biomechanical preparation, root canals were dried and filled with calcium hydroxide powder mixed with normal saline and access cavities were sealed with zinc oxide eugenol cement. After 7 days, calcium hydroxides dressing were removed with reamers and normal saline as irrigant (calcium hydroxide dissolved in this solution). The root canals were dried using absorbent paper points and obturated with zinc oxide eugenol cement using engine driven lentulo-spirals. Access cavities were sealed with silver amalgam/glass ionomer cement.

Recall visits were carried out after one week, one month and three months and six months. Success and failure of treatment was evaluated according to criteria laid down by Gutmann (1992) 15 (Table 1).

TABLE 1: Guidelines for clinical and radiographic success (adapted from Gutmann 1992)

RESULTS (TABLE 2, FIG. 1)

In single visit group.

Two patients came with swelling and pain after two days of obturation. Antibiotics and analgesics were prescribed to him. Symptoms disappeared after seven days.

One of the two patient reported with postoperative complication , reported with intraoral sinus. Filling material was removed from primary molar and patient was treated according to multiple visit group regimen.

Three Month

Remaining all patients were asymptomatic.

In Multiple Visit Group

All patients were asymptomatic.

Three Months

TABLE 2: Results

To compare the number of success with failure in two groups we apply Fisher Exact test. In the first week 18 out of 20 patients gives successful result in group I where in group II all 20 patients gives successful result. This gives the non significant difference in the results of two groups with test value 0.53 (p-value = 0.48) (if this p-value is <0.05 then we can say that there is significant difference in the outcomes of the groups).

After one month group I, 18 out of 20 patients show successful result, whereas in group II all 20 patients give successful result. This failure of two patients in group I is not significantly different from group II, having test value 0.53 (p-value = 0.48)

Since there is single patient which report negative result in group I against all 20 successful patients in group II after three month. This also shows nonsignificant difference in both the treatments having test value 0.001 and p-value 0.99.

After six months one patient from each group was not reported. So excluded from the analysis and from remaining 19 patients only single gives negative response in group I against all 19 positive responses in group II. This also shows nonsignificant differences with t-value 0.001 and p-value 0.99.

In all we can say that there is no significant difference in treatments results.

Positive results cases in two groups

In present study, patients in the age group of 4-7 years were selected because root formation of primary molars has been completed up to 4 years of age and root resorption of primary molars has not been started up to 7 years of age. Further patients were followed-up for six months so that any postoperative complications like pain, swelling, sinus formation can be evaluated. Primary molars which were cariously exposed, were selected for study.

Because in an infected vital pulp due to carious exposure, the infection is normally found only at the wound surface, where it has resulted in a localized inflammatory response. This means that in most apical portion of pulp tissue, micro organisms are usually not present. Root canal treatment in such cases is carried out on presumption that the pulpal condition is irreversible and may lead to tissue break down and subsequent root canal infection. 16 Root canal treatment in such cases can be carried out by single visit or multi visit therapy. So in present study equal criteria of case selection had been used for both groups.

Most of the studies comparing the success rate of endodontic therapy performed in one or more sessions have been based on poorly defined criteria of evaluation. Pekruhn 8 in a very large study, but without defined criteria, concluded that there were significantly fewer failures in the two-visit treatment group than in the one-visit treatment group. On the other hand, in a very controlled clinical study, Sjogren et al 17 investigated the role of infection on the outcome of one-visit treatment after a follow-up period of five years. Success was reported for 94% of the infected root canals associated with periradicular lesions that yielded negative culture, whereas in the samples which yielded positive culture prior to root filling, the success rate of treatment was 68%; thus, stressing the use of intracanal medication in infected cases (Table 3).

In another well-controlled study, Trope et al 18 investigated radiographic healing of teeth with periradicular lesions treated in one or two visits. In the two-visit group, root canals were medicated with calcium hydroxide for at least one week. After a one-year follow-up evaluation, the additional disinfecting action of calcium hydroxide resulted in a 10% increase in healing rates. This difference should be considered clinically important.

Katebzadeh and associates 19 , 20 histologically and radiographically compared periradicular repair after treatment of infected root canals of dogs performed in one or two sessions. They reported better results for the twovisit treatment in which calcium hydroxide was used as an intra canal disinfectant for one week.

In our study, the success rate in both techniques was almost equal with one patient reported with postoperative complications in single visit group. The results obtained are similar to that obtained by Rudner and Oliet (1981), 21 Trope et al (1999), 18 Katebzadeh et al (2000). 20 They also reported that success rate of multiple visit technique is slightly more than single visit technique.

The probable reason for this difference may be the fact that bacterial load can be decreased by additional dressing of calcium hydroxide as intra canal medicament between the appointments. Calcium hydroxide has been widely used in endodontics. Currently, this chemical substance is acknowledged as one of the most important antimicrobial dressing during endodontic therapy. 22 Most endodontic pathogens are unable to survive in a highly alkaline environment such as that of calcium hydroxide. Therefore, several bacterial species commonly found in infected root canals are eliminated after a short period when in direct contact with this substance. 23 The anti-microbial activity of calcium hydroxide is related to the release of hydroxyl ions in an aqueous environment. Direct contact experiments in vitro show that a 24-hour contact period is required for complete killing of enterococci. 24 In clinical experimentation, one week of intracanal dressing has been shown to safely disinfect a root canal system. 25 A study of 42 patients found that sodium hypochlorite irrigation reduced the bacteria level by only 61.9%, but use of calcium hydroxide in canals for one week resulted in 92.5% reduction. 26

In addition to killing bacteria, calcium hydroxide has ability to hydrolyse the lipid moiety of bacterial lipopolysaccharide (LPS), thereby inactivating the biologic activity of lipopolysaccharide (LPS) and reducing its effect. 27 , 28 This is very desirable effect because dead cell wall material remain after the bacteria have been killed and can continue to stimulate inflammatory response in the periradicular tissue.

TABLE 3: Studies evaluating healing of single visit and multiple visit root canal treatment

TABLE 4: Comparative studies on the incidence of postoperative pain after one-visit endodontics

Abbreviations: A = Anteriors; P = Posteriors; V = Vital; N-V = Non-vital.

Note: Severity: None to slight = patient took no analgesic, or a non-narcotic analgesic to relieve pain.

Moderate to severe = patient took narcotic analgesic for relief of pain.

Postoperative pain after non-surgical root canal treatment has been reported to range from app. 3 to 50% 4 , 33 , 34 (Table 4). In our study two patients reported with post operative pain in single visit group and no patient reported with pain in multiple visit group.

Ferranti 30 reported relatively low incidence of server pain following single visit procedure. O’Keefe 31 found no significant difference in postoperative pain experience by his patient following single visit or multiple visit root canal treatment. Soltanoff 7 used a random selection of cases treated during 20 years period to compare single and multiple visit treatment by degree of postoperative pain experienced found following single visit treatment more than 50% of his patient experienced pain. Roane et al 32 reported 2:1 higher frequency of pain following treatment completed in multiple visit as compared to that reported for those treated with single visit. Mulhern et al. 4 concluded that there was no significant difference in the incidence of postoperative pain between one-visit and multiple-visit endodontic treatment of asymptomatic pulpal necrosis. Moreover, pain associated with root canal therapy is poor indicator of pathosis and even more unreliable predictor of long term success. 35

We conclude that multiple visit and single visit root canal treatment demonstrated almost equal success. However, long term follow-up and big sample size are required to further corroborate the findings of this study. Most important aspect for success in pulpectomy cases is the indication of each case and then its subsequent treatment, be it multiple or single visit root canal treatment.

Briefly, in cases of vital pulp, a single-visit treatment should be used whenever possible. This is based on the fact that the pulp is only superficially infected and the root canal is free of bacteria, provided the aseptic chain is maintained during the intra canal procedures. Therefore, there is no apparent reason not to treat vital pulps in a single visit. Conversely, if the pulp is necrotic and/or associated with a periradicular disease, there is ample evidence that the root canal system is infected. 36 In these cases, the root canal system should ideally be cleaned and shaped, an intracanal medication placed, and the canal filled at a second appointment.

One visit endodontic should be viewed as a procedure that supplements and complements total patient care as it relates to endodontics and not as a technique that is going to totally replace multivisit procedures. Both single and multivisit treatments should be viewed as part of a total endodontic treatment spectrum, with the choice of one over the other being determined by the circumstances surrounding each individual case. The practitioner should not routinely apply one technique to all situations, but rather evaluate the circumstances peculiar to each particular case and then choose the technique tat best fits those circumstances. However, when doubt exists, the multiple visit procedure should be performed. Thus, the clinician will be most effectively utilizing his time in delivering the best possible endodontic service available to the patient. 14