Single versus multiple visits for endodontic treatment of permanent teeth.

backgroundRoot canal treatment (RoCT), or endodontic treatment, is a common procedure in dentistry. The main indications for RoCT are irreversible pulpitis and necrosis of the dental pulp caused by carious processes, coronal crack or fracture, or dental trauma. Successful RoCT is characterised by an absence of symptoms (i.e. pain) and clinical signs (i.e. swelling and sinus tract) in teeth without radiographic evidence of periodontal involvement (i.e. normal periodontal ligament). The success of RoCT depends on a number of variables related to the preoperative condition of the tooth, as well as the endodontic procedures. RoCT can be carried out with a single-visit approach, which involves root canal system obturation (filling and sealing) directly after instrumentation and irrigation, or with a multiple-visits approach, in which the treatment is completed in two or more sessions and obturation is performed in the last session. This review updates the previous versions published in 2007 and 2016.

objectivesTo evaluate the benefits and harms of completion of root canal treatment (RoCT) in a single visit compared to RoCT over two or more visits, with or without medication, in people aged over 10 years. SEARCH

methodsWe used standard, extensive Cochrane search methods. The latest search date was 25 April 2022. SELECTION CRITERIA: We included randomised controlled trials and quasi-randomised controlled trials in people needing RoCT comparing completion of RoCT in a single visit compared to RoCT over two or more visits.  DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were 1. tooth extraction and 2. radiological failure after at least one year (i.e. periapical radiolucency). Our secondary outcomes were 3. postoperative and postobturation pain; 4. swelling or flare-up; 5. analgesic use and 6. presence of sinus track or fistula after at least one month. We used GRADE to assess certainty of evidence for each outcome. We excluded five studies that were included in the previous version of the review because they did not meet the current standard of care (i.e. rubber dam isolation and irrigation with sodium hypochlorite). MAIN

resultsWe included 47 studies with 5805 participants and 5693 teeth analysed. We judged 10 studies at low risk of bias, 17 at high risk of bias and 20 at unclear risk of bias. Only two studies reported data on tooth extraction. We found no evidence of a difference between treatment in one visit or treatment over multiple visits, but we had very low certainty about the findings (risk ratio (RR) 0.46, 95% confidence interval (CI) 0.09 to 2.50; I AUTHORS'

conclusionsAs in the previous two versions of the review, there is currently no evidence to suggest that one treatment regimen (single-visit or multiple-visit RoCT) is more effective than the other. Neither regimen can prevent pain and other complications in the 12-month postoperative period. There was moderate-certainty evidence of higher proportion of participants reporting pain within one week in single-visit groups compared to multiple-visit groups. In contrast to the results of the last version of the review, there was no difference in analgesic use.