Prognosis of implants and abutment teeth under combined tooth-implant-supported and solely implant-supported double-crown-retained removable dental prostheses.

OBJECTIVE: Objective of this study was to evaluate the incidence of complications in dental implants and abutment teeth used for combined tooth-implant- and solely implant-supported double crown-retained removable dental prostheses (RDPs). MATERIAL AND METHODS: Patients were selected from a prospective clinical study. Seventy-three RDPs retained by 234 implants and 107 abutment teeth were placed in 39 men and 22 women with a mean age of 65 years. Forty-five RDPs were located in the maxilla and 28 in the mandible. Thirty-four RDPs were solely implant-supported and 39 were combined tooth-implant-supported. Kaplan-Meier analysis was used to estimate success defined as survival without severe abutment-related complications, and Cox regression was used to isolate the most relevant prognostic risk factors. RESULTS: After a median observation period of 2.7 years for the RDPs, six implants failed and eleven implants were diagnosed with peri-implantitis. Four abutment teeth were extracted, and three abutment teeth showed severe complications requiring extended interventions. For both abutment teeth and implants, Kaplan-Meier analyses revealed a 5-year probability of success of 85% for solely implant-supported RDPs and 92% for combined tooth-implant-supported RDPs. Multiple Cox regression identified RDP location (P = 0.01), age (P = 0.01), and gender (P = 0.04) as prognostic risk factors for severe implant-related complications. Solely implant-supported RPDs showed a poorer prognosis, but the risk difference did not reach statistical significance. CONCLUSIONS: Preliminary data suggest that the combination of teeth and implants to support double crown-retained RDPs may result in a prognostic advantage. The present findings should be validated in independent studies.

Early loading of implants with fixed dental prostheses in edentulous mandibles: 7.2-year clinical results from a prospective study.

PURPOSE: The purpose of this prospective follow-up study was to evaluate survival and success of early-loaded implants placed in the edentulous mandible and the survival of the fixed dental prostheses (FDPs) after in mean 7.2 years. MATERIALS AND METHODS: Thirty-seven patients (mean age 64.5 years, 18.9% male) received 185 implants in the intraforaminal area of the edentulous mandible (five implants per patient). Within 2 weeks, all implants were early loaded with fixed dental prostheses. The patients were recalled once a year for clinical and radiographic examinations. The 17 patients (79 implants) attending the recall in 2012 were additionally asked for their satisfaction of functional and aesthetic aspects. RESULTS: During a mean observation time of 7.2 years, 20 implants were lost in 11 patients, resulting in implant survival of 89.2%. Eight of all implants (4.3%) had too much marginal bone loss to satisfy the criteria of success. A total of 19 prosthetic complications and aftercare measurements had to be performed between in mean 4.5 to 7.2 years of observation. The survival of the original FDPs decreased to 83.8%. Of the 17 patients attending the recall in 2012, a total 59.5% had a satisfactory oral hygiene. According to the criteria of Albrektsson, the success rate for the remaining 79 implants was 89.9% after in mean 11.7 years. Patient satisfaction for assessment of functional and aesthetic aspects was in median 9 and 8 on the numeric rating scales. CONCLUSION: Long-term observation of in mean 7.2 years showed satisfactory results for both implant and superstructure survival. Prosthetic complications were easy to repair in most cases, but patients' ability for oral hygiene was reduced after the longer observation period. Especially in elderly patients, their attitudes and manual skills should be considered when planning the design of a new superstructure.

Survival of double-crown-retained dentures either tooth-implant or solely implant-supported: an 8-year retrospective study.

PURPOSE: To compare survival and incidence of complications for solely implant-supported double-crown-retained dentures (DCRDs) and combined tooth-implant-supported DCRDs for restoration of a complete jaw. MATERIALS AND METHODS: Patients were consecutively admitted to treatment at the Department of Prosthodontics, University of Heidelberg, during a time period from 2003 to 2011. Schedule and unscheduled visits were recorded on standardized documentation forms. Age, gender, location of implants, number of abutment teeth, jaw, and antagonist were assessed as possible factors affecting the number of complications per patient. RESULTS: Fifty-five patients with 66 DCRDs on 209 implants and 102 teeth were included. Of these, 30 dentures on 129 implants were solely implant-supported whereas the other 36 were combined tooth-implant-supported. During an observation period of up to 8.3 years (mean 3.4 years; SD 1.9) superstructure survival was 93.3% for the solely implant-supported DCRDs and 100% for the combined tooth-implant-supported DCRDs. Survival without major complications was 86.7% and 83.3%, respectively. Gender and location of both superstructure and implants were statistically associated with a greater number of complications. CONCLUSION: Within the limitations of this exploratory retrospective study, not only solely implant-supported DCRDs but also superstructures combining remaining teeth and implants within DCRDs might be a reliable treatment option for elderly patients. Prospective randomized clinical trials are needed to confirm this, however.

Clinical success of implant-supported and tooth-implant-supported double crown-retained dentures.

The objective of this retrospective study was to compare biological and technical complications of implant-supported and tooth-implant-supported double crown-retained dentures (DCRDs) with those of tooth-supported DCRDs. Sixty-three DCRDs were monitored. One study group included 16 prostheses with a combination of implants and natural teeth as double crowns (ti group), whereas in the second study group, 19 dentures were retained exclusively on implants (ii group); a third study group with 28 exclusively tooth-supported dentures served as controls (tt group). Tooth loss, implant failure, and technical complications (loss of retention of primary crown, abutment screw loosening, loss of facing, fracture of resin denture teeth and fracture of saddle resin) were analysed. During the observation period of 24 months, no implants or teeth were lost in the ti group and three technical complications were recorded. In the ii group, two implants were lost, two cases of peri-implantitis occurred and four technical complications were observed. In the tt group, two cases of tooth loss and seven technical complications were observed. At the time of the last examination, all prostheses of the ti group and the ii group were functional. Patients of these two study groups reported high satisfaction with both function and aesthetics with no significant difference between the two groups. Treatment with DCRDs showed comparable results in the three study groups. The 2-year results indicate that double crowns can be recommended for implant and combined tooth-implant-retained dentures.