Zirconia crowns cemented on titanium bars using CAD/CAM: a five-year follow-up prospective clinical study of 9 patients

Abstract Background The purpose of this prospective clinical study was to evaluate clinical results of the passive fit of the substructure in the Toronto bridge and the chipping or delamination of the ceramic veneering on the zirconia-support, after 5 years, in nine patients rehabilitated with zirconia crowns cemented on titanium bars using CAD/CAM technology. Methods A total of nine healthy patient fully edentulous in the upper and lower jaws with non-contributory past medical anamnesis needing full fixed total prosthesis maxilla and mandible were included in this clinical study, where a total 9 mandibles and 9 jaws were treated. The inclusion criteria in order for a patient to participate in the study were: a signed consent form, fully edentulous in the upper and lower jaws, required a full fixed total prosthesis restoration. The exclusion criteria were age limitation of less than 18 years old, chemotherapy, head and neck radiation therapy, diabetes or periodontal disease, smoking and severe illness. All patients received zirconia crowns cemented on titanium bars using CAD/CAM technology. The primary outcome of this study was to examine the survival rate of the zirconia crowns cemented on titanium bars using CAD/CAM technology during the observation period. Any chipping or delamination of the zirconia crowns of the restorations was considered as failure. The secondary outcome was to evaluate the passive fit of the substructure on the implants, loose of occlusal screws, implant survival and satisfactory occlusion. Results In 5 years of follow-up no evidence of chipping or delamination of the ceramic veneering on the zirconia crown supported were observed. Fifteen finished protesis (93.75%) showed satisfactory occlusion and only one case (6.25%) required significant occlusal adjustment. During the first year recall all bars were stable (100%) no mobility of protheses was recorded. After 5 years all bars were stable (100%) and no mobility of protheses was recorded. Conclusion The computerized workflow for the process of building bar and prosthesis ensures reproducible results and excellent adaptation and passive insertion of them, as well as conditions for avoiding mechanical complications and guarantees stability of screw-implant abutments. </jats:sec

Retrospective Analysis of Full-Arch Zirconia Rehabilitations on Dental Implants: Clinical Outcomes and Patient Satisfaction

The use of zirconia for full-arch Implant-Supported Fixed Complete Dental Prostheses (ISFCDPs) is common and reliable, with different techniques available for their design and fabrication. This retrospective study investigated prosthetic and implant survival/success rates and patients&rsquo; satisfaction for ISFCDPs produced with three different techniques: zirconia-on-titanium (milled zirconia arch glued to a titanium bar), progressive monolithic zirconia (entirely made of zirconia and directly screwed to the implants) and zirconia-on-zirconia (milled esthetic zirconia crowns glued to a milled high resistance zirconia frame). Fourteen patients (five males, nine females) aged 52&ndash;80 and treated with 14 ISFCDPs (86 implants) were included in this analysis. The mean follow-up at the time of recall was 36 months. Prosthetic and implant-related success rates were, respectively, 92.86% and 95.35%. No failures have been reported. One case of prosthetic chipping was observed; however, it was successfully repaired intraorally. Patients&rsquo; satisfaction was high: 78.57% were completely satisfied, 14.53% very satisfied and 7.14% satisfied. In conclusion, all the patients recommend treatment with ISFCDPs as full-arch prosthetic rehabilitation. The present study demonstrates positive clinical outcomes and high patients&rsquo; satisfaction. Further long-term, prospective studies with a larger cohort of patients are needed to confirm the advantages of the different prosthetic designs