Clinical outcome of 215 transmucosal implants with a conical connection: a retrospective study after 5-year follow-up

The purpose of this retrospective clinical study was to evaluate the survival rate (i.e. SVR – fixtures still in place at the end of the observation period) and success rate (i.e. SCR - bone resorption around implant neck) of an implant system characterized by cylindrical and tapered implants, both types of implant being equipped with a conical connection with an internal octagon (COC), both implant types having a 1.8 mm smooth neck, positioned above the bone crest level. A total of 65 subjects received 215 COCs between January 1996 and October 2011. All COCs were placed and restored by three experienced dental surgeons. The mean follow-up was 84±44 months. The patients involved in the study were both male (30) and female (35), of whom 30 were smokers (less than 20 cigarettes/day) and none was diabetic. The implants differed in terms of diameter and length, and were inserted both in the mandible (97) and in the maxilla (118). Sixty-seven implants were single tooth rehabilitations, and 148 prosthetic bridges. Fourteen had guided bone regeneration (GBR), and 10 were placed in post-extractive sites. Forty of the implants were provided with passing-screw abutments and 175 with full-screw abutments. The data were analyzed using descriptive statistics. None of the implants failed before prosthetic restoration, resulting in an SVR=100% after loading. The radiographic and clinical data revealed well-maintained, hard and soft tissue around the COCs, with an SCR=92.6%. Cox regression analyses did not detect any variables with statistical impact on the clinical outcome. In conclusion, Shiner XT implants are reliable tools for oral rehabilitation.