The Mineral Apposition Rate on Implants with Either a Sandblasted Acid-Etched Implant Surface (SLA) or a Nanostructured Calcium-Incorporated Surface (XPEED®): A Histological Split-Mouth, Randomized Case/Control Human Study

This study aimed to histologically evaluate the effects of XPEED (R) and SLA surface on the mineral apposition rate (MAR) at 3 and 5 weeks in titanium dental implants placed in human bone. In total, 17 titanium dental implants with XPEED (R) surface (n = 9) used as test and SLA surface (n = 8) used as control were included in this study. Each patient received four doses of tetracycline 500 mg at 12 h intervals 2 weeks prior to biopsy retrieval. Implant retrieval was performed, and retrieved biopsies were carefully treated for histomorphometric evaluation under epifluorescence microscopy. At 3 and 5 weeks, newly formed bone appeared in direct contact with both types of tested surfaces. At 3 weeks, the MAR value was, respectively, 2.0 (+/- 0.18) mu m/day for XPEED (R) implants and 1.5 (+/- 0.10) mu m/day for SLA implants (p = 0.017). At 5 weeks, lower MAR values for both XPEED (R) and SLA implants were noted, with 1.2 (+/- 0.10) mu m/day and 1.1 (+/- 0.10) mu m/day, respectively (p = 0.046). The overall evaluation by linear regression analysis for both time and implant surfaces showed a decreased osteoblast activity at 5 weeks compared to 3 weeks (p < 0.005). The results of the present study show that the bone apposition rate occurs faster around implants with XPEED (R) surface at 3 weeks and 5 weeks of healing. MAR values may support the use of implants with XPEED (R) surfaces in early loading protocols.