A randomized clinical trial comparing patient satisfaction and prosthetic outcomes with mandibular overdentures retained by one or two implants.

PURPOSE: This randomized clinical trial tested hypotheses that there are no differences in patient satisfaction, component costs, or treatment and maintenance times when mandibular overdentures are retained by one or two implants. MATERIALS AND METHODS: Subjects wearing conventional complete dentures were randomized to receive either one midline or two bilateral mandibular implants followed by a mandibular denture reline to incorporate implant retention. They indicated on a visual analog scale satisfaction with their dentures before implants and at 2 months and 1 year after implant retention. Satisfaction outcomes between the two groups were compared using the Wilcoxon/Mann-Whitney nonparametric rank test, while changes within each group were analyzed using signed-rank tests. Component costs and times for surgery, prosthodontic treatment, and maintenance were compared using nonparametric and t tests. RESULTS: Eighty-six subjects enrolled in this study and 85 completed the 1-year follow-up, at which median satisfaction was 93 (maximum 100) in the single-implant group and 94 in the two-implant group (P > .5). Within each group, median improvement in satisfaction was similarly dramatic (approximately 44) and significant (P < .001). Prosthodontic maintenance time was similar for both groups (P > .37), but the single-implant group had significantly lower component costs (P < .001) and lower times for surgery (P = .002), postsurgical denture maintenance (P = .021), and denture reline (P < .001). Five implants failed in four subjects, all in the two-implant group and all before denture reline. CONCLUSION: Lower component costs and treatment times, with comparable satisfaction and maintenance time over the first year, indicate that a mandibular overdenture retained by a single midline implant may be an alternative to the customary two-implant overdenture for maladaptive denture patients.

Mandibular overdentures supported by two or four endosseous implants: a 10-year clinical trial.

OBJECTIVE: The aim of this 10-year clinical trial was to evaluate the treatment outcome (condition of hard and soft peri-implant tissues, patient satisfaction, surgical and prosthetic aftercare) of mandibular overdentures supported by two or four implants. MATERIALS AND METHODS: Sixty edentulous patients with a mandibular height between 12 and 18 mm participated. Thirty patients were treated with an overdenture supported by two IMZ implants (group A) and 30 patients were treated with an overdenture supported by four IMZ implants (group B). Standardised clinical and radiographic parameters were evaluated 6 weeks after completion of the prosthetic treatment and after 1, 5 and 10 years of functional loading. Prosthetic and surgical aftercare was scored during the evaluation period, as well as patient satisfaction. RESULTS: There were no statistically significant differences with regard to any of the studied clinical or radiographic parameters of the peri-implant tissues between the groups. In addition, no differences in satisfaction and aftercare were observed between the groups. CONCLUSION: There is no difference in the clinical and radiographical state of patients treated with an overdenture on two or four implants during a 10-year evaluation period. Patients of both groups were evenly satisfied with their overdentures and received the same amount of aftercare. For reasons of cost-effectiveness, a two-implant overdenture is advised for patients with a Cawood classes IV-VI resorption of the mandible and complaints concerning retention and stability of the lower denture.

Postoperative tomographic assessment of veneer bone grafting with implant placement in the maxillary anterior region.

Various ridge augmentation and sinus lift procedures were performed in severely resorbed alveolar crests of a maxilla to provide some volume for implant treatment. It was reported that the outcome of maxillary sinus lift procedures was evaluated with conventional tomography or computerized tomography, and that grafted bone around implants markedly progressed in resorption, particularly at the implant apex. However, veneer bone grafting with implant placement has not been evaluated after treatment with imaging techniques. Therefore, the purpose of this study was to assess veneer bone grafting after maxillary anterior implant treatment. Seven patients with a mean age of 24 years, with implants placed in the maxillary anterior region with or without autogenous veneer bone grafting were postoperatively examined using conventional tomography. On tomograms, the ratio of bone-to-implant contact and the area of bone were measured in labial bones with bone grafts, and they were compared with the values without bone grafts. In cases with bone grafting, the average ratio of bone-to-implant contact was 63.6%, whereas 81.8% was formed in cases without bone grafting. The average area of bone was 12.9 mm and 23.4 mm in patients with and without bone grafting, respectively. No significant difference was found between the implants with and without bone grafts. Resorbed labial bone was observed in the maxillary anterior region with and without veneer bone grafting.

The cost of dental implants as compared to that of conventional strategies.

The effectiveness of dental implants is widely studied, especially in terms of their clinical outcomes. However, from the policymaker's point of view, variables other than safety and efficacy, such as the costs and effectiveness of dental implants as compared to other treatment alternatives, are vital in decision making. This paper compares the costs of different treatment strategies in a randomized clinical trial in patients with resorbed mandibles and persistent problems with their conventional dentures: treatment with a mandibular overdenture on permucosal dental implants, an overdenture on a transmandibular implant, new dentures after preprosthetic surgery, and new dentures only. Data were gathered on an individual patient level to gain insight into specific cost episodes. Direct costs were subdivided into labor, material, technique, and overhead. Data concerning these components were gathered during the consecutive treatment phases in the first year. Results show that the resources used to treat a patient with an overdenture supported by a transmandibular implant are seven times those of a complete new set of dentures. Comparison of the cost ratio of an implant-retained overdenture supported by permucosal implants and conventional new prostheses proves less unfavorable: 1:3. New dentures after preprosthetic surgery are almost as expensive as treatment with permucosal implants.