Zirconia Implant Supported Fixed Complete Dental Prostheses: an observational retrospective study

OBJECTIVES: Zirconia used for Implant Supported Fixed Complete Dental Prostheses (ISFCDPs) exhibits favourable biocompatibility and high flexural strength compared to resinous materials. Zirconia can be used as a prosthesis glued to an inner frame or as a single-piece prosthesis obtained from a disk of progressive zirconia, with a stronger inner layer and more aesthetic external layers. The objective of the present retrospective study is to evaluate and compare the success, survival and complications over time of ISFCDPs made with a single piece of progressive zirconia or with aesthetic Zirconia glued to a stronger zirconia frame.

METHODS: 11 Patients who received a total of 14 superior or inferior ISFCDPs were included in the study: 3 Progressive Zirconia ISFCDPs and 11 Zirc-On-Zirc ISFCDPs. Panoramic radiographies were performed for each patient, along with prosthetic and implant evaluations and a satisfaction questionnaire.

RESULTS: 86 implants and 14 ISFCDPs have been evaluated; the average follow up time was 35.7±19.8 months. The average esthetic satisfaction was 9.6±0.6 out of 10, and the average functional satisfaction was 9.7±0.6 out of 10. For the Zirc-On-Zirc ISFCDPs, one case of minor chipping of the pink zirconia was reported out of six cases, which evolved in a framework fracture and prosthesis replacement at 12 months. For progressive Zirconia ISFCDPs no complications were reported. Out of 86 implants, five had at least one site with PPD of 5mm or higher, and none failed.

CONCLUSIONS: By analyzing the data obtained, it can be stated that the two different uses of zirconia (Progressive or Zirc-On-Zirc) for the ISFCDPs don’t seem to have any difference in terms of performance and patient satisfaction. This is probably due to the pre-surgical planning of the prosthetic rehabilitation and its standardization in design and production.