C J WATSON*, A R OGDEN and J RUSSELL. (Division of Restorative Dentistry and Division of Oral Maxillofacial Surgery, Leeds Dental Institute, Leeds. UK)
Over the last six years 433 hydroxylapatite (HA) coated implants manufactured by Calcitek have been placed in 124 patients. Only one patient has experienced the complete loss of 2 implants giving an overall success rate of 99.5% . Plaque and gingival indices, pocket depth measurements, percussion measurements (Periotest), crevicular fluid volume flow (Periotron) and radiographs were regularly recorded for all implants. Of a11 these clinical measurements, radiographic findings proved to 4e the best diagnostic evaluation of implant integration. Marginal bone loss greater than 3mm was found in 3% of implants supporting mandibular fixed bridges, 15% of single tooth implants and 18% of overdenture abutments. In the maxilla overdenture abutment bone loss of greater than 3mm was shown in 46% of cases. Peri-implantitis and bone loss were associated with low pH levels at the implant abutment junction. If bone loss in excess of 3mm continues, the likely long-term success rate falls to 96% in the mandible and 69% in the maxilla.
This study has shown that Calcitek HA coated implants all initially integrated and there was no early failure. Follow up of maxillary overdenture cases has shown significant crestal bone cratering which if it continues will pose a significant risk to long term implant survival.