IADR Abstract Archives
A Tri-Oval Design Favors the Osseointegration of Immediately Loaded Implants
Objectives: High peri-implant interfacial strain is correlated with bone resorption. A novel tri-oval implant design was developed to create a combination of high strain and low strain peri-implant environments. The aim of this study is to test whether the tri-oval implants could ensure both implant primary stability and rapid osseointegration when subjected to immediate functional loading.
Methods: 48 8-week-old male CD1 wild-type mice were used for this split-mouth study. Bilateral maxillary first molars were extracted. After four weeks of tissue healing, both conventional round and novel tri-oval titanium implants were inserted into the healed tooth extraction site and subjected to functional masticatory loading. At multiple time points after implant placement, mechanical testing, finite element modeling, and histologic, cellular, and molecular assays were performed to evaluate the tissue-implant interface.
Results: Although the insertion torque was equivalent for both implants, tri-oval implants exhibited greater primary stability than round implants. This superior primary stability minimized implant movement when subjected to masticatory loading and led to significant lower peri-implant stress and strains. The zone of apoptotic osteocytes around tri-oval implants was significantly narrower, which coincided with less peri-implant bone resorption. At the same time, Cell proliferation and bone mineralization were more robust around tri-oval implants. We then tested whether the superior primary stability and more active bone turnover of the tri-oval implants had a long-term benefit, by subjecting both round and tri-oval implants to masticatory loading immediately after placement. In contrast to the round implants that exhibited a significant dip in stability that eventually led to their failure, the tri-oval implants fully osseointegrated because stability was maintained throughout the osseointegration period.
Conclusions: The novel tri-oval implant provides a favorable mechanically and biologically pro-osteogenic environment for peri-implant bone formation and accelerated the process of osseointegration.
Methods: 48 8-week-old male CD1 wild-type mice were used for this split-mouth study. Bilateral maxillary first molars were extracted. After four weeks of tissue healing, both conventional round and novel tri-oval titanium implants were inserted into the healed tooth extraction site and subjected to functional masticatory loading. At multiple time points after implant placement, mechanical testing, finite element modeling, and histologic, cellular, and molecular assays were performed to evaluate the tissue-implant interface.
Results: Although the insertion torque was equivalent for both implants, tri-oval implants exhibited greater primary stability than round implants. This superior primary stability minimized implant movement when subjected to masticatory loading and led to significant lower peri-implant stress and strains. The zone of apoptotic osteocytes around tri-oval implants was significantly narrower, which coincided with less peri-implant bone resorption. At the same time, Cell proliferation and bone mineralization were more robust around tri-oval implants. We then tested whether the superior primary stability and more active bone turnover of the tri-oval implants had a long-term benefit, by subjecting both round and tri-oval implants to masticatory loading immediately after placement. In contrast to the round implants that exhibited a significant dip in stability that eventually led to their failure, the tri-oval implants fully osseointegrated because stability was maintained throughout the osseointegration period.
Conclusions: The novel tri-oval implant provides a favorable mechanically and biologically pro-osteogenic environment for peri-implant bone formation and accelerated the process of osseointegration.