A 5-year comparison of hydroxyapatite-coated titanium plasma-sprayed and titanium plasma-sprayed cylinder dental implants

Objective, A preliminary report from this study showed that hydroxyapatite-coated (HA) titanium plasma-sprayed (TPS) cylinder implants had fewer failures than TPS cylinder implants before prosthetic loading. The purpose of this article is to report the long-term success associated with the 2 systems. In addition, local and systemic factors that may influence the success or failure of the implants were analyzed. Study design. Each of 65 subjects was randomized to either HA-coated TPS or TPS cylinder implants. Loss of an implant was considered a failure. Failures were analyzed in terms of the coating of the implant, age and gender of the patient, location and length of the implant, opposing dentition, and smoking status. Data were statistically analyzed through use of chi-quare tests. Results, Of 351 implants that were placed, 13 were lost before prosthetic loading and 17 were lost after prosthetic loading. The overall success rate was 92.8%. Three hundred thirty-eight implants were prosthetically loaded. The implant success rate after prosthetic loading was 95.3%. There was an overall nonsignificant higher failure rate for the TPS implants (8.0%). Patient age and patient gender were nonsignificant variables. Ten-mm implants had a significantly higher failure rate (17.4%; chi-square, 1.00; P=.39). Before prosthetic loading, more implants Failed in the posterior mandible; after prosthetic loading, more implants failed in the anterior maxilla (chi-square, 8.97; P=.03). More implants failed when they were opposed by natural dentition or hybrids (chi-square, 7.36; P=.007). Smoking history was a significant factor (chi-square, 5.2; P=.002). Conclusions. Statistically, there is little difference between the 2 systems. Local and systemic factors appear to play a greater role in implant failure than does the surface of the implant.