Clinical Significance of the Use of Resonance Frequency Analysis in Assessing Implant Stability: A Systematic Review

Purpose: To assess any correlations between resonance frequency analysis (RFA) and other clinical measurements, namely changes in marginal bone level. Materials and Methods: A systematic review was performed to investigate the relationship between RFA and changes in marginal bone level. Clinical studies published up to May 1, 2018, were searched in electronic databases, including PubMed/MEDLINE, Embase, and Cochrane, using the following MeSH terms: resonance frequency analysis; implant stability quotient; RFA; and ISQ, in combination with marginal bone level; marginal bone loss; and marginal bone resorption. Results: A total of 62 articles were included in this review after all abstracts and full-text articles were examined according to the inclusion/exclusion criteria. The Results and Discussion sections of investigations reporting both marginal bone level changes and RFA measurements were presented. Relevant findings regarding relationships between RFA and bone quality or insertion torque were also summarized. Most articles reported an overall increase in ISQs over the observation time; however, contradictory findings were found regarding the relationships between RFA measurements, marginal bone loss, and other parameters. Conclusion: A definitive conclusion could not be made, as mixed results were found in the few articles that reported significant associations and correlations between RFA measurements and bone loss, while others concluded the opposite. Heterogeneity between the studies further complicated interpretation. Longitudinal RFA measurements may still be valuable for evaluating implant stability when applied as a supplementary tool to radiographic assessments and other clinical examinations.