Interventions for replacing missing teeth: treatment of perimplantitis.

BACKGROUND: One of the key factors for the long-term success of oral implants is the maintenance of healthy tissues around them. Bacterial plaque accumulation induces inflammatory changes in the soft tissues surrounding oral implants and it may lead to their progressive destruction (perimplantitis) and ultimately to implant failure. Different treatment strategies for perimplantitis have been suggested, however it is unclear which are the most effective.

OBJECTIVES: To identify the most effective interventions for treating perimplantitis around osseointegrated dental implants.

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 the identified randomised controlled trials (RCTs) and relevant review articles for studies outside the handsearched journals. We wrote to authors of all identified RCTs, to more than 55 oral implant manufacturers and an internet discussion group to find unpublished or ongoing RCTs. No language restrictions were applied. The last electronic search was conducted on 28 June 2004.

SELECTION CRITERIA: All RCTs of oral implants comparing agents or interventions for treating perimplantitis around dental implants.

DATA COLLECTION AND ANALYSIS: Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in duplicate and independently by two reviewers. We contacted the authors for missing information. Results were expressed as random effect models using weighted mean differences for continuous outcomes and relative risk for dichotomous outcomes with 95% confidence interval (CI). Heterogeneity was to be investigated including both clinical and methodological factors.

MAIN RESULTS: Only two eligible trials were identified, but one was excluded due to insufficient data presented. The included study compared the use of locally applied metronidazole gel versus ultrasonic debridement in patients affected possibly by a slight form of perimplantitis. Both interventions were repeated 1 week after. Twelve weeks after treatment there was no statistically significant difference in probing pocket depths among the two groups (mean difference = 0.1; 95% CI -0.59 to 0.79). No side effects occurred. This trial was judged to be at high risk of bias.

REVIEWERS' CONCLUSIONS: There is no reliable evidence suggesting which could be the most effective interventions for treating perimplantitis. This is not to say that currently used interventions are not effective. More quality research is needed.