Peri-implant alveolar bone resorption in an innovative peri-implantitis murine model: Effect of implant surface and onset of infection

Purpose: To compare the difference in alveolar bone resorption around implants after immediate placement in a bacterial induced experimental periimplantitis murine model. The various conditions that were examined were: Effect of implant surface characteristics and the onset of the induced infection. Materials and Methods: Screw-shaped titanium implants, smooth-surface or sand-blasted large-grit acid-etched (SLA) coated, were inserted immediately after extraction of the first upper left molar, in 90 5-6-week-old BALB/c mice. The mice were infected with Porphyromonas gingivalis and Fusobacterium nucleatum 21 (early infection) or 42 days (delayed infection) after implantation. Six weeks post infection, bone volume around inserted implants was measured using micro-CT, and was compared to alveolar bone level around teeth. Histological analysis was also performed. Results: The level of bone loss was significantly higher around the implants compared to the teeth, for smooth surface implants the bone loss was higher than of the SLA surface in both control and infected groups with no statistical significance. The survival rate of the implants in immediate infection was 75% compared of the 100% survival of the delayed infection and control mice. There is no significant difference between the early and the delayed infection in alveolar bone loss level around the implants. Conclusions: This model can assist in studying the differences in alveolar bone resorption in different implants and their effect on the development of the disease.