The performance of two-implant overdentures in the atrophic maxilla: a case series with 1-year follow-up.

PURPOSE: To assess the implant and prosthesis survival rates, the clinical, radiographical and patient-related outcome measures, and the masticatory performance of maxillary overdentures supported by two implants in patients with an atrophic maxilla. METHODS: In this case series, 15 consecutive patients who were eligible for maxillary implant overdenture therapy, but who had insufficient bone volume to place at least four implants and were unwilling to be treated with reconstructive surgery were asked to participate. After giving consent, participants received two implants in the maxilla under local anaesthesia. After 3 months of osseointegration, a maxillary overdenture with palatal coverage and solitary attachments was fabricated. Implant and overdenture survival, marginal bone level change, clinical outcome measures, masticatory performance and patient-related outcomes were evaluated at baseline and 1 year after overdenture placement. RESULTS: Fourteen out of 15 participants completed the follow-up period of 12 months. Implant and overdenture survival rate were 89.3% and 85.7%, respectively. Change in marginal bone level (- 0.5 ± 0.7 mm), change in probing depth (0.0 ± 1.0 mm), and clinical outcomes were favourable. Masticatory performance and patient-related outcomes improved significantly compared to baseline. Complications were minimal. CONCLUSIONS: Within the limitations of this study, it can be concluded that patients with extreme resorption of the maxilla that are unwilling to be treated with reconstructive surgery, benefit from two-implant maxillary overdentures retained by solitary attachments in terms of improved masticatory functioning and denture satisfaction. However, they have relatively high risk of implant loss. TRIAL REGISTRATION: UMCG Trial Register (RR201900060), registered 22 January 2019.

Incidence of peri-implant mucositis and peri-implantitis in patients with a maxillary overdenture: A sub-analysis of two prospective studies with a 10-year follow-up period.

BACKGROUND: Though studies on maxillary overdentures show satisfying results on implant survival, patient-related outcomes and prosthetic complications, the epidemiology of peri-implant diseases in this specific group of patients has hardly been reported. While the general patient-level prevalence of peri-implant mucositis and peri-implantitis are estimated at ~45% and ~20%, respectively, the risk of developing these diseases within a specific period is less clear. To fully appreciate the epidemiology of peri-implant diseases, more long-term data on incidence of peri-implant diseases are needed. PURPOSE: The purpose of this sub-analysis of two prospective studies was to assess the incidence of peri-implant mucositis and peri-implantitis in fully edentulous patients with implant-retained maxillary overdentures during a 10-year follow-up period. MATERIALS AND METHODS: One hundred and sixteen patients treated with implant-supported maxillary overdentures were available from two clinical trials. Data on biological complications, clinical and radiographical parameters were collected for 106 patients at 5-year, for 82 patients at 10-year follow-up. The incidence was calculated following the consensus of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions. Extent and severity then were calculated to enable an appropriate epidemiological description of peri-implantitis. RESULTS: The patient-level incidence of peri-implant mucositis was 37.7% after 5 years and 64.6% after 10 years whereas the patient-level incidence of peri-implantitis was 10.4% after 5 years and 19.5% after 10 years. After 10 years, the extent of peri-implant mucositis and peri-implantitis is 52.8% and 43.8%, respectively. In terms of severity, 26.5% of all affected implants suffered from >3 mm bone loss and 17.6% of all affected implants was lost. CONCLUSION: Three of five fully edentulous patients with implant-supported maxillary overdentures experience peri-implant mucositis after 10 years. Peri-implantitis occurs in one of five patients after 10 years. In spite of these incidence rates, implant survival remains high.

Utilising the nasal aperture for template stabilisation for guided surgery in the atrophic maxilla.

BACKGROUND: Templates aim to facilitate implant placement in the prosthetically preferred position. Mucosa-supported and bone-supported templates are commonly used in the edentulous maxilla. In the atrophic maxilla (Cawood V and VI), however, these templates can be easily displaced due to a lack of supportive tissues, even in cases where anterior sites offer sufficient bone for implant placement. To assist in positioning and stabilisation, we designed a template that utilises the nasal aperture as a fulcrum to create a forced and exclusive fit. The aim of this study was to assess the clinical usability of the developed template and the corresponding implant placement accuracy in patients with edentulous atrophic maxillae. Deviations between planned and placed implant positions were measured by aligning pre- and post-operative cone beam computed tomography scans. RESULTS: Twenty-four implants were placed in 11 patients. One template did not fit properly due to a slight undercut. All implants could be placed with good primary stability. The implants had high accuracy at the implant shoulder (global deviation 1.1 ± 0.5 mm, lateral deviation 0.8 ± 0.5 mm) and a mean angular deviation of 7.2 ± 3.4°. CONCLUSIONS: The developed surgical template offers stabilised and secure template placement in the edentulous atrophic maxilla, resulting in satisfying implant placement accuracy when using a semi-guided approach. TRIAL REGISTRATION: Netherlands Trial Register, NL6561, registered 26 September 2017.