Bone Graft Osseous Changes After Maxillary Sinus Floor Augmentation: A Systematic Review

This systematic review aimed to evaluate computed tomographic scans for volumetric bone gain following lateral sinus floor augmentation of the atrophic posterior maxilla after the use of various bone-grafting materials. The databases MEDLINE, EMBASE, CINAHL, Cochrane Central Registry of Controlled Trials (CENTRAL), and SCOPUS were used for a comprehensive search for all potentially eligible randomized controlled trials (RCTs), without language restrictions, from the beginning of each database until June 2021. The predictor variables for this review were autogenous bone (AB), allografts (AG), xenografts (XG), and alloplastic bone (AP), which were assessed individually and in combination with the inclusion of growth factors with XGs. The outcome variable was the graft volume on cone beam computerized tomographic (CBCT) scans. Seven RCTs with a short-term observation period were included. Topographical analyses of all graft materials identified a volumetric reduction at 6 months postgrafting, compared with values immediately after graft placement. The volumetric reduction occurred regardless of the type of bone-grafting material. The largest volumetric gain over baseline, pregraft values, was found in the AG+XG group. Autografts, the present gold standard bone graft, showed a high resorption rate and inferior volumetric increase when compared with alternative grafting combinations. AG and XG also showed a significant difference with less volumetric gain than AP and their combinations. No difference was detected between AP and AG+AP. However, there was significantly less volumetric gain for AP alone compared with AG+XG and XG-growth factor combinations. As a result, these findings suggest significant advantages to new bone formation using grafting materials in combination. To achieve a better understanding of topographical variables related to various grafting materials, more clinically focused RCTs, with sufficient statistical power to control for confounding factors, are needed.