Risk of early implant failure in grafted and non-grafted sites: A systematic review and meta-analysis

Purpose: To assess whether bone grafting is associated with early implant failure (defined as a lack of osseointegration detected prior to functional loading) and to evaluate the association between bone grafting procedures and other risk factors for early implant failure. Materials and methods: Two independent reviewers conducted an electronic search of MEDLINE (via PubMed). Meta-analysis was performed for the odds ratio of bone grafting procedures associated with early implant failure. The Newcastle-Ottawa Scale for cohort studies was used to assess the risk of bias. Results: Of the 231 articles selected for full-text review, 10 were included in the qualitative analysis and for quantitative meta-analysis. An odds ratio of 1.50 (95% confidence interval 1.06-2.13) was recorded for bone grafting procedures associated with early implant failure. Data regarding the association of bone grafting and other risk factors in determining early implant failure were insufficient for quantitative analysis. Conclusions: Within the limitations of this study, a significant positive association was found between bone grafting procedures and early implant failure. The possible negative effect of bone grafting procedures on implant osseointegration should be considered when planning implant therapy.