Histological evaluation of bone formation adjacent to dental implants with a novel apical chamber design: preliminary data in the rabbit model.

BACKGROUND: Wound healing events after implant placement will vary according to the extent of the necrotic zone. PURPOSE: The goal of the present study was to evaluate bone healing around titanium implants with a novel apical chamber design. MATERIALS AND METHODS: Titanium implants grade 4 were turned with different apex design. Control implants had a self tapping design with centric cutting grooves. Test implants exhibited eccentric cutting grooves interconnected by a hollow chamber. A total of 60 implants were installed in the femur/tibia of 10 rabbits for histological analysis. RESULTS: After 1 week, immature bone formation started at the cortical level of the test implants associated to scalloped contours indicative of bone resorption. Control implants failed to show new bone formation, and the space within the threads was filled mainly by red blood cells and surgical debris. Bone contact values showed no difference after 1 week, and significant higher values for test implants showed likewise after 4 weeks compared with control implants in the tibia. CONCLUSION: This experimental study verifies the beneficial effect of bone formation in the chamber at the apical part of the fixture coupled to a faster bone healing to implants placed in dense bone.