Reliable Method for the in vitro Assessment of Dental Implant Stability. A Comparison Study of Damping Capacity Measurement with the Periotest Instrument and Resonance Frequency Analysis with the Osstell Instrument

Reliable Method for the in vitro Assessment of Dental Implant Stability. A Comparison Study of Damping Capacity Measurement with the Periotest Instrument and Resonance Frequency Analysis with the Osstell Instrument
S. LACHMANN, B. J?—GER, G. GOMEZ-ROMAN, D. AXMANN, and H. WEBER, University of Tuebingen, 72076 Tuebingen, Germany
2003
IADR
Objective: We assessed primary implant stability in vitro applying (1) resonance frequency analysis (RFA, Osstell instrument) and (2) damping capacity measurement (Periotest instrument). The aim of this study was to investigate the reliability in the performance of each of these instruments and to relate the measurements of these instruments to each other. Material and methods: Several series of commercial dental implants were inserted into different bovine rib blocks. Repeated measurements were performed using RFA and damping capacity measurement, respectively, varying (1) the torque-in force of the devices' attachment screw, (2) the bone quality and (3) the thread exposure in simulated peri-implant bone defects. Both instruments were compared with each other by assessing the associated measurement errors, intraclass-correlations and scatterplots. Results: The associated measurement errors were 0.5 ISQ units for RFA and 0.4 Periotest units for the damping capacity. Additionally, common (intra-class-) correlations were calculated, and each of which resulted nearly in 1.0. A first analysis of the associated scatterplot calculated a Rsquare of 0.8 between the measurements of both instruments. Attachment screws tightened with 10 Ncm torque-control produced slightly higher values for implant stability with both methods compared to manual attachment, but not of clinical importance. The results of both techniques showed inter-implant deviation in insertion stability due to variations of local bone quality and artificially created peri-implant bone defects. Conclusion: In these idealized in-vitro experiments both techniques showed similar results with regard to reliability and classification of implant stability. Remarkably, measurements were statistically dependent only on (1) bone quality and (2) artificially created peri-implant bone loss. Values from adjacent implants could not be related to each other. It may however be deduced from the experiments that in cases of peri-implant defects RFA and damping capacity assessment may be of importance in the long-term follow-up of implant integration.