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Objectives Functional tooth replacement and bone regeneration are parts of the daily practice in modern dentistry, but wellreproducible and relatively inexpensive experimental models are still missing. We aimed to develop a new small animal model to monitor osseointegration utilizing the combination of multiple evaluation protocols. Material and methods After cutting the tail between the C4 and C5 vertebrae in Wistar rats, costume made, parallel walled, nonthreaded implants were placed into the center of the tail parallel with its longitudinal axis using a surgical guide. Osseointegration of the titanium implants was followed between 4 and 16 weeks after surgery applying axial extraction force, and resonance frequency analysis as functional tests, and histomorphometry and micro-CT as structural evaluations. Results In functional tests, we observed that both methods are suitable for the detection of the time-dependent increase in osseointegration, but the sensitivity of the pull-out technique (an approximately five times increase with rather low standard error) was much higher than that of the resonance frequency analysis. In structural evaluations, changes in the detected bone implant contact values measured by histomorphometry (yielding 1.5 times increase, with low variations of data) were more reliable than micro-CT based evaluations to screen the developments of contact between bone and implant. Conclusion Our results provide evidence that the caudal vertebrae osseointegration model is useful for the preclinical evaluation of implant integration into the bone. Clinical relevance The combination of the biomechanical and structural tests offers a well-reproducible small animal system that can be suitable for studying the integration of various implant materials and surface treatments.

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Abstract

Abstract-Since the discovery of the osseointegration implant stability has an increasing relevance. Determination of stability is particularly important for dental implants. Two types of stabilities give us information about the success of implantation; primary and secondary stability. There are many stability indicators, but their meanings are not exactly defined theoretically. The aim of our study was to examine and evaluate the insertion and removal torque of novel implant geometry in polyurethane artificial bone blocks with different densities, corresponding to the standard living bone density classification (D1-D4). Protocols given to implantation were followed during the drilling and insertion.With the analysis of the torque functions we found differences among the polyurethane artificial bone blocks. Torque functions showed us how the function's slope has changed the characteristic max-min values in different polyurethane artificial bone blocks. The drilling parameters highly influenced the characteristic of the torque functions.