EFFECT OF USING POLYETHER ETHER KETONE VERSUS METAL MESH REINFORCEMENT ON FRACTURE RESISTANCE OF MAXILLARY POLYMETHYL METHACRYLATE DENTURE BASES. AN IN-VITRO STUDY.

ABSTRACT Aim: The aim of this study was to evaluate the effect of different reinforcing materials on the fracture resistance of maxillary dentures reinforced by either PEEK or metal framework meshes. The weight of reinforced dentures in both groups was also calculated. Methodology: 14 reinforced complete dentures were fabricated with similar denture base thickness and same arrangement of teeth by duplication of trial denture bases through custom made stone mold and silicon mold for teeth arrangement. The dentures were divided into 2 groups. In the first group, the dentures were reinforced with metal meshes while in other group PEEK meshes of the same thickness was used for the reinforcement. Mesh reinforcement in both groups were digitally designed by EXO-CAD dental software on scanned cast, printed, and then fabricated in either of the two materials: metal or PEEK. Each denture was subjected to load from a universal testing machine using a fissure load applicator at mid palatal area at speed of 5mm/min. The load at failure manifested by sharp drop to below 50% on load-deflection curve was recorded in Newton. Before the load application, the weight of each denture in both groups was evaluated. All collected data were statistically analyzed. Fracture pattern of dentures in both groups was visually assessed. Results: A statistically significant difference (P= 0.004) in the maximum average load the dentures could withstand before fracture was found between the two groups. Metal reinforced maxillary dentures could withstand maximum average load of 1686.63 ±325.06 N with corresponding value of 1160.22 ±197.21 (N) for PEEK reinforced dentures. Also using PEEK mesh decreased weight of denture by 26% compared to metal reinforced denture. Conclusions: PEEK mesh with thickness of 0.7 to 0.9 mm did not influence the fracture strength of complete dentures compared to metal mesh with the same thickness.