Tilted Implants for the Rehabilitation of Edentulous Jaws: A Systematic Review

Medium- and Long-Term Complications in Full-Arch Rehabilitations Supported by Upright and Tilted Implants

PURPOSE

The purpose of this retrospective investigation was to present the incidence of biological and technical complications in patients treated with implant-supported, immediately loaded full-arch restorations.

MATERIALS AND METHODS

Clinical data of all patients treated with full-arch, immediately loaded rehabilitations supported by a combination of upright and tilted implants were screened. Data on both technical and biological complications (such as peri-implant mucositis and peri-implantitis) and their onset and frequency of occurrence were recorded and analyzed.

RESULTS

The clinical records of 86 patients (95 prosthetic rehabilitations) were included in this study. There were 61 mandibular rehabilitations and 34 maxillary ones, all of them immediately loaded within 8 to 48 hours of the surgical intervention. The follow-up time varied from 16.3 to 112 months of function (mean 65.36 months). The most common biological complications were hygiene-related (n = 81; 30.2% of patients displayed peri-implant mucositis and 10.4% peri-implantitis). Among all prosthetic complications, the detachment of an element of the definitive prosthesis was the most frequent event (n = 20; 23.2% of patients). The total number of prosthetic complications was 42. Most complications were reversible and did not affect the overall implant/prosthesis survival rate.

CONCLUSIONS

The occurrence in well-maintained patients of technical and biological complications in full-arch rehabilitations supported by a combination of tilted and upright implants in the medium to long term is lower than previously reported by the pertinent literature. Further studies are needed to confirm this result.

Tilted trans-sinus implants for the treatment of maxillary atrophy: case series of 35 consecutive patients

PURPOSE

To evaluate tilted trans-sinus implants for rehabilitation of the atrophic maxilla.

MATERIALS AND METHODS

A case series of 35 patients (32 consecutive edentulous and 3 partially edentulous patients) treated with trans-sinus dental implants is presented. Edentulous patients received 4 or 6 implants depending on anatomic conditions and a 12-unit final restoration; partially edentulous patients received 2 implants supporting a 3-unit partial fixed bridge.

RESULTS

Thirty-five patients (14 men, 21 women) underwent rehabilitation. Thirty-two patients with 190 implants placed received a full-arch fixed prosthesis supported by axial and trans-sinus tilted implants. Three patients each received 2 implants with a 3-unit fixed restoration. The mean age at surgery was 59.2 ± 9.5 years. The cumulative survival rate was calculated only for the full-arch fixed prosthesis group and was 98.42%. Crestal bone loss averaged 0.9 ± 0.4 and 0.8 ± 0.5 mm for the axial and tilted implants, respectively, at the 12-month evaluation. Biological complications at the implant level were 1 case of peri-implantitis and 3 cases of mucositis; no patient developed sinus infections. The prosthetic complications encountered were screw loosening in 17.5% of cases and chipping of the esthetic part in 30% of cases. These complications were easily resolved chairside and did not lead to prosthetic failure.

CONCLUSIONS

Trans-sinus tilted implants and sinus membrane distal displacement appear to be a viable minimally invasive alternative for the treatment of maxillary atrophy.

Immediate versus conventional loading of post-extraction implants in the edentulous jaws

PURPOSE

This retrospective study deals with the issue of how to realize the transition from a failing dentition to an implant-supported prosthesis. The main aim was to assess the reliability of immediate implant and immediate loading (IL) protocols in the edentulous jaws. A further aim was to investigate the role of patient-related, implant-related, and surgery-related secondary variables in the occurrence of implant failure.

MATERIALS AND METHODS

Patients with at least a 4-year post-loading follow-up undergoing the transition from a failing dentition to an implant-supported prosthesis were retrospectively investigated. Primary variables of implant failure were immediate placement and IL. Secondary variables were categorized as demographic, anatomic, site, and prosthetically related. Cumulative survival rates (CSRs) were compared using the Kaplan-Meier survival estimate method. Predictors of failure were included in a multivariate Cox regression model to evaluate the simultaneous effects of multiple covariates and control for correlated observation. Crestal bone loss was also measured at the delayed and the immediately loaded implants.

RESULTS

Five hundred nineteen implants rehabilitating 91 jaws in 80 patients were followed. The Kaplan-Meier survival estimate method showed that immediate implant and IL decreased the CSR significantly in the maxilla but not in the mandible. Some secondary variables were found to affect the CSR: maxillary location, age over 70 years, prostheses supported by only immediate implants or a majority of them, temporary cementation, implant diameter, and length. Crestal bone loss was not significantly related to the outcomes.

CONCLUSIONS

The present data may provide clinical recommendations to the practitioner treating the transitional patient. In the mandible, the use of immediate implants and IL does not increase the failure rate. In the maxilla however, combining immediate placement and IL may significantly increase the failure rate.