An oral and maxillofacial surgery practice placed and evaluated 690 hydroxyapatite-coated dental implants from 1985 to 1993. Many implants were placed in patients with compromised conditions, such as lack of bone height or width. Advanced surgical procedures were used. Factors that were considered in assessing the success of the implants included anatomic position, sex of the patient, and length of the implant. The study showed that although shorter implants were more likely to fail than longer implants, the cumulative survival rate up to 88 months was 96.5%.