Histomorphometric study of machined titanium implants and calcium phosphate coated titanium implants

Kang, Hyun Joo; Yang, Jae Ho

Abstract

PURPOSE
The objective of this study was to investigate the effects of calcium phosphate coated titanium implant surface on bone response and implant stability at early stage of healing period of 3 weeks and later healing period of 6 weeks. MATERIAL AND METHODS: A total of 24 machined, screw-shaped implants (Dentium Co., Ltd., Seoul, Korea) which dimensions were 3.3 mm in diameter and 5.0 mm in length, were used in this research. All implants (n = 24), made of commercially pure (grade IV) titanium, were divided into 2 groups. Twelve implants (n = 12) were machined without any surface modification (control). The test implants (n = 12) were anodized and coated with thin film (150 nm) of calcium phosphate by electron-beam deposition. The implants were placed on the proximal surface of the rabbit tibiae. The bone to implant contact (BIC) ratios was evaluated after 3 and 6 weeks of implant insertion.
RESULTS
The BIC percentage of calcium phosphate coated implants (70.8 +/- 18.9%) was significantly higher than that of machined implants (44.1 +/- 16.5%) 3 weeks after implant insertion (P = 0.0264). However, there was no significant difference between the groups after 6 weeks of healing (P > .05).
CONCLUSION
The histomorphometric evaluation of implant surface revealed that: 1. After 3 weeks early healing period, bone to implant contact (BIC) percentage of calcium phosphate coated implants (70.8%) was much greater than that of surface untreated machined implants (44.1%) with P = 0.0264. 2. After 6 weeks healing period, however, BIC percentage of calcium phosphate coated implants group (79.0%) was similar to the machined only implant group (78.6%). There was no statistical difference between two groups (P = 0.8074). 3. We found the significant deference between the control group and experimental group during the early healing period of 3 weeks. But no statistical difference was found between two groups during the later of 6 weeks.