Long-term Follow-up Cases of Implantation of Hydroxyapatite Granules in Periodontal Osseous Defects. 1. Survival Rate and Survival Characteristics of Teeth.

Abstract

We investigated the survival of teeth that were subjected to a flap operation with implantation of hydroxyapatite (HAP) granules in periodontal osseous defects. For 70 cases over a five-year period, the survival rates for individual tooth type were determined every year. The influence of the following conditions on survival of the teeth was considered: 1) whether the patient recall at the appropriate interval was consistent; 2) whether the tooth was splinted; 3) whether the tooth had furcation involvement; and 4) how deep the probing pocket depth was at the flap operation. The survival rate for all teeth was 87% after five years, and it decreased with the passing years.The rate decreased drastically after 7 to 8 years, and it was 47% after 10 years. The survival rate by individual tooth type was 44% for upper molars, the lowest among all types of teeth; 75% for upper incisors and canine teeth; 91% for lower incisors and canine teeth and 72% for lower premolars. Teeth with furcation involvement tended to be lost. Keeping a appointment recall, splinting, and probing pocket depth at the operation appeared to have little effect upon tooth survival.Thus, despite the conditions of the teeth, HAP implant applied to a single-rooted tooth with a periodontal osseous defect resulted in a good long-term prognosis.