Background: Dental implants are available in different materials, shapes and with different surface characteristics. In particular, numerous implant surface modifications have been developed for enhancing clinical performances.
Objectives: To test the null hypothesis of no difference in clinical performance between various root-formed osseointegrated dental implant types.
Search strategy: We searched the Cochrane Oral Health Group's Trials Register, The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE. Handsearching included several dental journals. We checked the bibliographies of relevant clinical trials and review articles for studies outside the handsearched journals. Two extensive personal libraries were consulted. We wrote to authors of the identified randomised controlled trials (RCTs), to more than 55 oral implant manufacturers; we used personal contacts and we asked on an internet discussion group in an attempt to identify unpublished or ongoing RCTs. No language restriction was applied. The last electronic search was conducted 21st March 2003.
Selection criteria: All RCTs of oral implants comparing osseintegrated implants with different materials, shapes and surface properties having a follow up of at least 1 year.
Data collection and analysis: We carried out a quality assessment of the included RCTs and contacted the authors for missing information. We independently extracted the data in duplicate. We followed the Cochrane Oral Health Group's statistical guidelines.
Main results: Twenty-five different RCTs were identified. Ten of these RCTs, reporting results from a total of 428 patients, were suitable for inclusion in the review. Nine different implant types were compared with a follow up ranging from 1 to 3 years. All implants were made in commercially pure titanium and had different shapes and surface preparations. On a patient rather than per implant basis there were no statistically significant differences for failures, marginal bone level changes on intraoral radiographs and peri-implantitis between various implant systems.
Reviewer's conclusions: There was no evidence that any of the implant systems evaluated was superior to the other. However, these findings are based on a few RCTs all having short follow-up periods and few participants. More RCTs should be conducted, with follow up of at least 5 years and including a sufficient number of patients to detect a true difference if any exists. Such trials should be reported according to the CONSORT guidelines (http://www.consort-statement.org/).