Success of Hydroxyapatite vs. Titanium Implants: 5 year results

Methods: Each of 120 edentulous patients received HA threaded, HA cylindrical, and Ti threaded implants in a randomized split-plot design using 5 or 6 implants per patient. Digital radiography provided yearly measurements of bone loss; calibrated clinicians measured, mobility, gingival index, plaque index, and recession.

Results: There was no significant difference in the gingival index, plaque index, or mobility at 5 years for HA and Ti coated implants. At 5 years, mean bone loss was significantly lower for HA cylinders (0.01±0.10 mm) and HA threaded (0.03±0.17 mm) than Ti threaded (0.5±0.20) (p<.02). A Kaplan-Meier analysis was used to compare the proportion of ailing implants, using the strict criterion that successful implants must lose less than 2 mm of bone support over 5 years. This analysis revealed that 95.2% of Ti threaded implants, 97.92% of HA coated threaded implants and 99.0% of HA cylinder implants were successful by this criterion (p<0.06).

Conclusions: These results indicate that all types of implants placed in this study had high success rates above 95%. Over 5 years the success rate tended to favor HA coated implants.