The focus of this in vitro study was to develop a laboratory method, intended for future research of aspects of implant-Smartpeg complex stiffness and its possible influence on the overall RFA-based implant stability determination. In the past, other laboratory methodologies have been engineered to investigate implant deflection and/or lateral displacement by means of transducers. A setup using a motorized load transducer enabling to impact imbedded implant through a customized mounted abutment in combination with a micrometer gauge is described [18]. Furthermore, induction of resonant vibration on imbedded implants by an impulse-forced hammer, detection of the vibration signal by an acoustic microphone, and subsequent signal processing by fast Fourier transformation are described [19].

By means of the above-described laboratory setup, quantitative measurement of maximum resonance frequency was performed after Smartpeg stimulation with subsequent indirect calculation of ISQ values using the Osstell algorithm. These indirect computed ISQ values were compared to directly determined ISQ values through the Osstell IDx device. The comparison of the indirect and direct ISQ datasets enabled to evaluate the correctness of the laboratory procedure by using the algorithm proposed by Osstell. Since the signal processing software provided a maximum resonance frequency based on 1000 recorded excitation measurements for each single analysis with a frequency resolution of 32 Hz, a measurement technique with high power could be obtained. The calculated ISQ values matched well with the directly generated ISQ values recorded by the IDx device. The difference between indirect and direct ISQ was rejectable from a clinical point of view.