LONG-TERM EVALUATION OF SINGLE-CRYSTAL SAPPHIRE IMPLANTS AS ABUTMENTSIN FIXED PROSTHODONTICS

49 patients participated in a prospective study of treatment of total or partial edentulism with fixed prosthodontics supported by Bioceram( R) sapphire implants. 15 patients were treated for maxillary or mandib ular edentulism, and 7 for a missing maxillary anterior tooth. The rem aining 27 patients, with Applegate-Kennedy Class I-IV residual dentiti ons, were treated with fixed bridges supported by free-standing implan ts, or bridges supported by teeth and implants. Implant success, prost hesis stability, radiographic marginal bone level as well as parameter s for peri-implant health were evaluated. The study began in 1982, and clinical treatment of the last patients was completed in 1988, i.e., a follow-up period ranging from 7 to 13 years. Of the patients treated for total mandibular edentulism, one implant fractured after 6 years in situ. The bone implant score (BIS) values for those implants were a t the time for the bridge cementation 63.5+/-1.4 and at 1, 2, 3 and 5 year follow-ups 62.1+/-1.4, 61.9+/-1.5, 61.5+/-1.6, and 60.95+/-1.3, r espectively. The success rate was 100%, 100% and 97.7% for the mandibl e at 3, 5 and 10 years, respectively. Of the 7 edentulous patients tre ated with maxillary fixed bridges, 6 implants in 1 patient had to be r emoved after 1 year in service. Another 2 patients lost all their impl ants, 6 each, after 36 months. 6 implants in the 4th patient did not f ulfil the criteria for success and were rated as failures at the four year follow-up. The success rate was thus 58.1%, 44.2% and 44.2% for t he maxilla at 3, 5 and 10 year follow-ups, respectively. Of the 7 pati ents in whom single missing teeth were replaced, 1 implant in the prem olar region was lost during the 1st year post-operatively, but no othe r complications or changes in BIS were observed. Of the 27 patients tr eated for partial edentulism (56 implants total) 1 implant, of a 4-uni t free standing maxillary bridge fractured after 6 years and was later replaced. There were no statistically significant differences in BIS changes for the implants when used as abutments for partial maxillary or mandibular edentulism. The cumulative success rates for the implant s in the partially maxilla were 96.3, 92.6 and 92.6 at the 3,5 and 10 years respectively and 100% in the mandible over the whole period.