Evaluation of Mini-Screw Implant Stability with OsteoCrete Bone Cement

Abstract

The purpose of this study was to evaluate the stability of mini-screw implants (MSIs) placed with and without OsteoCrete bone cement. Using a randomized split-mouth design in 6 skeletally mature male beagle dogs, 23 MSIs were placed in the maxillary alveolar bone with OsteoCrete and 23 MSIs were placed without OsteoCrete. MSI stability was evaluated each week with an Osstell IDx. Histology was used to analyze the surrounding bone of the control and OsteoCrete MSIs. Micro-CT was used to analyze the bone volume fraction and the bone mineral density around the MSIs. The success rate of the control MSIs (87%) was higher than the success rate of the experimental MSIs (78.3%), but the difference was not statistically significant (p=0.437). All of the MSI failures occurred between weeks 1 and 4. MSIs inserted with OsteoCrete exhibited an initial decrease in primary stability, but they did not show the increases in secondary stability seen in the control MSIs. Bone mineralization occurred around the outer boundaries of OsteoCrete but not within the OsteoCrete. The OsteoCrete was not being actively remodeled by osteoclasts. There was no difference in bone volume fraction or bone mineral density in the layer of bone around the OsteoCrete and control MSIs. In conclusion, OsteoCrete does not make MSIs more stable; it makes them less stable.