No confidence that success rates of self-drilling and self-tapping insertion techniques of orthodontic mini-implants are similar

Data sourcesMedline, Cochrane Central Register of Controlled Trials (CENTRAL), Embase, China National Knowledge Infrastructure (CNKI) and SIGLE.Study selectionRandomised controlled trials(RCTs), clinical controlled trials (CCTs) and cohort studies that assessed the success/failure rates of self-drilling and self-tapping mini-screws for orthodontic anchorage were considered.Data extraction and synthesisData was abstracted and assessed for quality by two reviewers independently. The Newcastle-Ottawa scale (NOS) was used to evaluate the methodological quality. Meta-analyses with subgroup analysis of different study designs, follow-up periods, participant age and immediate loading or delayed loading were conducted.ResultsThree CCTs and three cohort studies were included. These were assessed to be of high quality. Meta-analysis (six studies) showed no difference in success rates between the two types of screws; odds ratio (OR) = 0.90 (95%CI; 0.52-1.53). Meta-analysis (two studies) found no difference in the rate of root contact between the two systems; OR = 0.96 (95% CI; 0.53-1.71).ConclusionsCurrently available clinical evidence suggests that the success rates of self-tapping and self-drilling miniscrews are similar. Determination of the position and direction of placement should be more precise when self-drilling miniscrews are used in sites with narrow root proximity.