Objective: To evaluate the clinical effectiveness, common complications and maintenance associated with hydroxylapatite (HA) coated cylindrical implants when used to support single crowns.
Design: A prospective medium term clinical study of the Calcitek HA-coated implant.
Setting: Implant placement, crown fabrication and follow-up procedures were carried out at the Leeds Dental Institute, between 1990 and 1998.
Subjects and method: 26 patients (33 implants) participated in the trial. They were referred from general dental practitioners because of their suitability for single tooth implant placement.
Main outcome measures: The implants were assessed using recognised clinical review procedures e.g. radiographs and soft tissue assessments.
Results: At exposure there was 100% implant integration. The cumulative survival rate over 4 years was 100%. In five implants there was cervical bone loss of more than 4 mm and these were classified as failing. This gave an overall cumulative success rate of 58% by year 4.
Conclusion: The Calcitek HA-coated single tooth implant shows exceptionally high initial integration however, the longer term results suggest that the cervical bone level adjacent to the implant failed to establish a steady state. Doubts remain regarding the long-term prognosis of these cylindrical HA-coated implants.