Alveolar Bone Architecture: A Systematic Review and Meta-Analysis

Background: There is a need for studying bone characteristics systematically for a better understanding of planning (i.e., timing of placement and loading) and outcomes of implant therapy. Therefore, the aim of the present review is to evaluate alveolar bone microarchitecture and its modifiers. Methods: Two independent reviewers conducted electronic and manual literature searches in several databases, including MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane Oral Health Group Trials Register, for articles published up to February 2015 reporting alveolar bone microstructure. The random-effect model was applied to calculate the weighted mean (WM) of total bone volume (TBV), which has a range from 0 to 1. TBV was stratified by anatomic locations, atrophic status, and types of specimens. Correlations between TBV and other bone-related parameters were also analyzed. Results: A total of 800 articles were initially identified. After abstract/full-text review, 24 articles were included in the systematic review, of which 23 were also included in the quantitative analysis. The WM TBV was 0.365 (95% confidence interval = 0.278 to 0.452), higher in the maxillary/mandibular anterior sites than the maxillary/mandibular posterior sites. However, great variations existed within each anatomic location. Additionally, WM TBV was lower in atrophic sites than non-atrophic sites. TBV was correlated negatively with trabecular spacing (R-2 = 0.11). Conclusions: The present systematic review suggests that the TBV might not be different between the defined anatomic locations. However, the atrophy status might influence TBV.