Comparative Assessments, Meta-Analysis, and Recommended Guidelines for Reporting Studies on Histomorphometric Bone-Implant Contact in Humans

Purpose: To evaluate factors that have an influence on histomorphometric bone-to-implant contact (BIC) of dental implants in humans. Materials and Methods: Using inclusion/exclusion criteria, eligible studies were searched in five databases and handsearched in 11 journals. A total of 351 articles were assigned to full text analysis. The extracted data were assigned to comparative statistical assessments and meta-analysis. Results: A total of 55 articles were included in the analysis. The mean BIC found in comparative assessments and meta-analysis of implants in the mandible (70.97 and 69.744 ± 3.304, respectively) was higher than those in the maxilla (53.24 and 56.692 ± 3.598; P = .000 and P = .008, respectively). The mean BIC in the anterior mandible (79.42) and maxilla (74.19) were higher than the posterior mandible (69.14) and maxilla (36.68) (P .05). Differences were detected in BIC of commercially available implants and experimental micro-implants (P .05). Comparative assessments and meta-analysis showed that conventionally loaded implants (75.70 and 75.786 ± 4.889, respectively) had higher BIC than unloaded (54.07 and 53.24 ± 4.971, respectively) and immediately loaded implants (58.53 and 68.831 ± 4.972; P = .000 and P = .004, respectively). Conclusions: Based upon a meta-analysis of the literature the following conclusions can be made: The BIC in the mandible is higher than the maxilla. The BIC is higher in the anterior than the posterior regions. The implant design coupled with the anatomical region affects the amount of BIC. Placement of experimental micro-implants with different surfaces in the posterior region always result in low and almost comparable BIC. The loading state and healing period seems to have an influence on BIC. Specific reporting guidelines are required to improve reporting of studies on human BIC.