Evaluation of implant-supported carbon/graphite fiber-reinforced poly (methyl methacrylate) prostheses. A longitudinal multicenter study.

Carbon/graphite fiber-reinforced poly (methyl methacrylate) (CGFP) has been suggested as an alternative framework material for implant-supported fixed prostheses. The aim of this study was to evaluate CGFP prostheses clinically over time in patients treated with titanium implants of the Brånemark type and to study the handling of the material in the technical production. Twenty-five patients were fitted with 27 CGFP prostheses supported by 119 implants. Three implants, all in the upper jaw, were lost after loading. After a mean functioning time of 44 months (range 32-56), 19 prostheses (70%) were still in situ. In all, 5 prostheses fractured, of which 3 were exchanged whereas 2 could be repaired. The fractures were discovered early after loading and located close to the end abutment cylinders. During the follow-up period, the bone loss around the implants was about the same as earlier reported values for fixed prostheses with cast frameworks. It is concluded that a CGFP framework can be used to form the biocompatible superstructure of implant-supported prostheses with high precision at a low material cost and with good aesthetic results. The mechanical properties are so far not satisfactory but the method has the potential to be further developed and standardized.