Clinical agreement between scale-aligned damping capacity and resonance frequency analyses for implant stability: a retrospective method-comparison study.

Abstract

Purpose: This study aimed to evaluate the clinical agreement between resonance frequency analysis (RFA) and 2 scale-aligned damping capacity analysis (DCA) devices for assessing implant stability.

Methods: In this retrospective method-comparison study (890 implants from 600 patients), implant stability was measured at up to 4 time points (T0-T3) using 1 RFA device and 2 DCA devices. Correlations between devices were assessed using Pearson's correlation coefficient. Agreement was evaluated using modified Bland-Altman analysis, and diagnostic accuracy was determined using receiver operating characteristic (ROC) curve analysis with an implant stability quotient threshold of 70. Changes in stability according to initial torque and simultaneous guided bone regeneration (GBR) or sinus grafting were analyzed using non-parametric statistical methods.

Results: Significant moderate positive correlations were observed between RFA and each DCA device (r≈0.4; P<0.001), and a strong correlation was observed between the 2 DCA devices (r=0.7; P<0.001). Modified Bland-Altman analysis revealed systematic discrepancies, with DCA devices tending to overestimate stability in lower stability ranges relative to RFA. ROC analysis demonstrated fair diagnostic accuracy for both DCA devices (area under the curve≈0.70). Initial insertion torque and simultaneous GBR significantly influenced early implant stability; however, these differences diminished after 3 months.

Conclusions: Scale-aligned DCA devices demonstrated acceptable clinical agreement and fair diagnostic accuracy relative to RFA. However, systematic discrepancies between DCA and RFA were observed, particularly in implants with lower stability. Clinicians should therefore interpret DCA measurements with caution in such cases.