Modal Damping Factor Detected with an Impulse-Forced Vibration Method Provides Additional Information on Osseointegration During Dental Implant Healing

Purpose: To evaluate whether resonance frequency (RF) analysis combined with modal damping factor (MDF) analysis provides additional information on dental implant healing status. Materials and Methods: In in vitro tests, epoxy resin was used to simulate the implant healing process. The RF and MDF values of the implants were measured during the entire polymerization process. Implant stability quotient (ISQ) and Periotest values (PTVs) from Ostell and Periotest devices were used to validate the apparatus. In in vivo experiments, vibrational analysis was performed on 17 dental implants in 12 patients. The RF and MDF values of the tested implants were recorded during the first 10 weeks after surgery. The effects of jaw types and primary stability on MDF healing curves were analyzed. Results: In the in vitro model, the RF values obtained from the apparatus used in this study were similar to those obtained from the Osstell device. Unlike the Periotest healing curve, the MDF curve showed a 1.8-fold increase during the early phase. In clinical experiments, the mean RF values were unchanged during the first 2 weeks and increased continuously until 6 weeks. The corresponding mean MDF value decreased over time and reached 0.045 ± 0.011 at 10 weeks, which is approximately 50% lower than the initial value. Although the RF values of the implants with higher initial frequency remained unchanged during the healing period, the MDF values decreased significantly. Conclusion: Analysis of RF combined with MDF provides additional information on dental implant healing status. MDF analysis can detect changes in the implant/bone complex during the healing period even in implants with higher RF values. Keywords: implant, modal damping factor, osseointegration, vibration analysis