Flap Management in Alveolar Ridge Preservation: A Systematic Review and Meta-Analysis

Purpose: This systematic review aimed to identify the effects of certain flap management procedures on ridge preservation on the basis of existing literature. Materials and Methods: Electronic (MEDLINE, EMBASE, and Cochrane Central Register of controlled trials) and manual searches of the literature were conducted until February 2017. Randomized controlled trials (RCTs), controlled clinical trials (CCTs), and prospective cohort studies that involved at least 10 subjects were eligible for this systematic review. To evaluate the beneficial effects of flap management on ridge preservation, changes in the bone width, bone height, and keratinized gingiva width were calculated using a random effects model. Results: Eleven studies (nine RCTs and two CCTs) were included in this review. No statistically significant differences in bone width and height changes were identified between the flapped and flapless ridge preservation techniques and between the free gingival graft and flapless ridge preservation techniques. A statistically significant shrinkage in keratinized gingiva width was noted with flapped ridge preservation compared with flapless ridge preservation (weighted mean differences, −3.21 mm; 95% confidence interval, −4.10 to −2.33; P .00001; heterogeneity, 51%; χ2, 0.15). Conclusion: Within the limitations, this review reveals that flapless ridge preservation was more effective in preserving bone width, bone height, and keratinized gingiva width. To present pertinent evidence regarding which flap management should be recommended for ridge preservation, more controlled and high-quality studies are warranted. Keywords: animal experiments, biomaterials, bone regeneration, flap management, guided tissue regeneration, ridge preservation