Single-visit more effective than multiple-visit root canal treatment?

Abstract

Literature was searched using the Cochrane Controlled Trials Register (CENTRAL), Medline, Embase and HealthStar databases. Reference lists from identified articles were scanned and a further search made using names of authors of the identified articles. Papers that had cited these publications were also identified through the Science Citation Index to identify potentially relevant subsequent primary research. Two reviewers scanned all titles and abstracts. An article was included if subjects had a no relevant medical history; subjects presented with mature teeth with infected necrotic root canals and radiographic evidence of periapical bone loss (as an indication of preoperative canal infection), all selected root canals had not received any endodontic treatment previously, participants underwent nonsurgical root canal treatment during the study, and the number of teeth showing radiographic evidence of healing was the outcome measure. Data were abstracted by two reviewers. The principal measure of treatment effect was risk difference with the fixed-effect method for combining study estimates being used to produce an overall estimate. Between-study heterogeneity was assessed using standard χ2 test or Q-statistic. Only three randomised controlled trials (RCT) were identified and included in the review, covering a total of 146 cases. Sample size of all three studies was small. None demonstrated a statistically significant difference in healing rates. Risk differences (RD) of included studies were combined using the inverse variance-weighted method (pooled RD, −6.3%; 95% confidence interval, −20.3 to +7.8). Based on the current best available evidence, single-visit root canal treatment appears to be slightly more effective than multiple visits, that is, it had a 6.3% higher healing rate. The difference in healing rate between these two treatment regimens was not statistically significant (P=0.3809), however.