Surgical versus non-surgical endodontic re-treatment for periradicular lesions

Background: Though success rates of endodontic initial treatment have been improving over the years, persistence of periapical disease is far from being a rare condition. The most common therapeutical options for the re-treatment of teeth with periapical pathosis are non-surgical orthograde treatment and surgical treatment. Selection between alternative treatments should be based on assessment of respective benefits (mainly healing) and risks from studies consistent with a high level of evidence. Objectives: To test the null hypothesis of no difference in outcome between surgical and non-surgical therapy for endodontic re-treatment of periradicular lesions. Search strategy: The Cochrane Oral Health Group Trials Register, CENTRAL, MEDLINE and EMBASE were searched with appropriate search strategies. Handsearching included eight dental journals. The bibliographies of relevant clinical trials and relevant articles were checked for identifying studies outside the handsearched journals. Seven manufacturers of instruments in the field of endodontics or endodontic surgery or both, as well as the authors of the identified randomized controlled trials (RCTs) were contacted in order to identify unpublished or ongoing RCTs. No language restriction was placed. The last electronic search was conducted on 3rd April 2007. Selection criteria: All RCTs about re-treatment of teeth with periapical pathosis in which both surgical and non-surgical approaches were used and having a follow up of at least 1 year were considered for the analysis. Data collection and analysis: A quality assessment of the included RCTs was carried out and the authors were contacted for missing information. We independently extracted the data in duplicate. We followed the Cochrane Oral Health Group's statistical guidelines. Main results: Three RCTs were identified, two of them reporting different data from the same clinical study. The risk of bias was judged as moderate for one study and high for the other one. One hundred and twenty-six cases were followed up for at least 1 year, and 82 had a follow up of 4 years. At the 1-year follow up the success rate for surgical treatment was slightly better than non-surgical (risk ratio (RR) 1.13; 95% confidence interval (CI) 0.98 to 1.30). When the follow up was extended to 4 years (only one RCT made it) the outcome for the two procedures became similar. Authors' conclusions: The finding that healing rates can be higher for cases treated surgically as compared to those treated non-surgically, at least in the short term, is based on two RCTs only. A single RCT reported that in the medium to long term healing rates for the two procedures are very similar. There is currently scarce evidence for a sound decision making process among alternative treatments for the retreatment of a periradicular pathosis. More well-designed RCTs should be performed with follow up of at least 4 years, and with a consistent sample size, to detect a true difference in the long term between the outcomes of the two alternative treatments, if any exist.