Hydroxyapatite-Coated Oral Implants: A Systematic Review and Meta-Analysis

Purpose: To evaluate treatment outcomes of hydroxyapatite-coated implants in comparison to nonhydroxyapatite- coated implants. Materials and Methods: A comprehensive electronic search was performed through MEDLINE, EMBASE, the Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), the UK National Research Register, and Conference proceedings citation index up to June 2011. Additionally, several journals, bibliographies of selected articles, and relevant reviews were manually searched. Results: A total of seven studies (one randomized, four prospective, and two retrospective) were included. The quality of the studies was assessed "better" for the randomized and prospective and "fair" for the retrospective. Over a mean observation period of at least 5 years, the survival rates ranged from 77.8% to 98.1% for the hydroxyapatite-coated implants and from 77.1% to 95.2% for the nonhydroxyapatitecoated implants, with no significant differences observed. Hydroxyapatite-coated implants were associated with lower but insignificant failure risk compared with nonhydroxyapatite-coated implants (risk ratio of 0.68; 95% CI 0.33 to 1.41; P = .30). Marginal bone loss quantified in a single study was significantly higher around hydroxyapatite implants (1.51 ± 2.71 mm versus 0.55 ± 1.04 mm; P .001). Conclusions: Hydroxyapatitecoated implants demonstrate short-term survival outcome up to 5 years, which is comparable to that of nonhydroxyapatite-coated implants. The long-term success of hydroxyapatite-coated implants using welldesigned clinical trials remains lacking in the literature. Keywords: hydroxyapatite-coated implants, meta-analysis, systematic review