L.W. LINDQUIST*, G. E. CARLSSON & T. JEMT (Department of Prosthetic Dentistry and The Brånemark Clinic, Göteborg University, Göteborg, Sweden)
Objective. By using a prospective design 47 edentulous patients were followed for 12 to 15 years after treatment with mandibular fixed prostheses supported by osseointegrated Brånemark implants.
Methods. The study was performed by means of questionnaires, clinical and radiographic examinations and various recordings at scheduled follow-up occasions.
Results. Three (1%) of the 273 inserted implants were lost, two before and one six years after placement of the fixed prosthesis. The cumulative success rate (CSR) of the implants was 98.9% both after 10 and 15 years. None of the fixed prostheses was lost and at the last follow-up, all patients had stable fixed prostheses in function (CSR 100%).The marginal bone loss around the implants was small, on average 0.5 mm during the first post surgical year and thereafter about 0.05 mm annually. More bone was lost around the anterior implants than around the most posterior ones. Smoking and poor oral hygiene had significant influence on bone loss, while occlusal loading factors such as maximal bite force, tooth clenching and length of cantilevers were of minor importance.
Conclusions. The long-term results of the mandibular implant treatment were extremely successful, regarding both the fixed prostheses and implant stability. Bone resorption around the implants, albeit limited, was influenced by several factors, smoking and oral hygiene appeared to be most important.