The implant surface and its role in affecting the dynamic processes of bone remodeling by means of distance osteogenesis: A comparative in vivo study.

This study aimed to evaluate whether different surface modifications affect the dynamics of bone remodeling at the implant and the adjacent local bone. Seventy-two dental implants with different surfaces (smooth and rough control [smCtrl; rCtrl], smooth and rough + O2-plasma spray [smPlas; rPlas], smooth and rough + nanocrystalline SiO2-hydroxyapatite coating [ncSiO2HA] + O2-plasma spray [smNB-C; rNB-C]; each n = 12) were bilaterally inserted into the femora of 36 New Zealand white rabbits. Intravital fluorochrome labeling was performed to visualize the dynamics of bone formation. The objectives were quantification of bone-to-implant contact (BIC [%]) at 2 and 4 weeks and the dynamic bone formation (dbf [%]) at the implants' adjacent local bone within 1, 2, and 3 weeks. After 2 weeks, BIC was significantly higher for both smNB-C (BIC: 59% ± 2% SEM) and rNB-C (BIC: 66% ± 3% SEM) compared with controls (BIC: 42% ± 1% SEM; P < .005). After 4 weeks, BIC for rNB-C (65% ± 2%) was superior to all test groups (BIC: 39% ± 2% SEM; P = .012). Regarding dbf (%), neither within 1 (P = .88), 2 (P = .48), nor after 3 weeks (P = .36) did any differences occur among the groups, even in accordance to the implant level. Although distance osteogenesis seems crucial for the development of secondary stability and thus of osseointegration, it apparently does not get affected by a bioactive ncSiO2HA surface coating. Changing the surfaces' release kinetics and composition may increase distance osteogenesis.