Turned surface implants in patients treated for periodontitis: Preliminary 10- to 20-year results of a long-term cohort study

Purpose: This long-term cohort study investigated the prevalence of mucositis, peri-implantitis, bone loss and survival of turned surface implants in partially edentulous patients treated for periodontitis. Materials and methods: 19 patients treated for generalised chronic periodontitis (GCP) and 20 patients treated for generalised aggressive periodontitis (GAP) were orally rehabilitated with a total of 126 dental implants. Examinations were performed before implant insertion, at the time of superstructure insertion, and in the subsequent years during a 3-month recall schedule over a 10- to 20-year period. At every session, clinical parameters were recorded. Intraoral radiographs were taken after insertion of superstructures and 1, 3, 5, 10, 15 and 20 years later. Results: In total, nine implants were lost during the 20-year observation period. The implant survival rate was 92.1% (GCP patients) and 90.1% (GAP patients). After 10 years, mucositis was present in 21.9% and 21.2% of implants in GCP and GAP patients, respectively. The risk of mucositis was significantly lower in patients with a removable superstructure (OR = 0.061 with P = 0.001). Peri-implantitis was present in 12.2% implants (GCP patients) and 14.1% implants (GAP patients). Implants inserted in bone quality grade 3 showed a significantly higher risk of peri-implantitis (OR = 5.658 with P = 0.003). After 10 years, implants in GAP patients did not show a significant higher bone loss (1.87 ± 1.40 mm) compared with implants in GCP patients (1.50 ± 1.30 mm). After 20 years, the total mean peri-implant bone loss was 1.98 ± 1.64 mm, almost every fifth implant revealed a bone loss > 3 mm. Conclusions: The implant survival rate in both patient groups was > 90%, and implants showed a moderate mucositis ( 30%) and peri-implantitis ( 25%) rate. Bone quality and type of superstructure seem to have had an influence on peri-implant health. These results suggest that patients with a history of periodontitis treated in a tight recall schedule can be successfully rehabilitated with turned surface implants for a follow-up period of 10 to 20 years. Keywords: bone loss, long-term cohort study, mucositis, patients with periodontitis, peri-implantitis, survival, turned surface implants Conflict-of-interest statement: The authors declare that they have no conflicts of interest.