Evaluation of Some Mechanical Properties of CAD/CAM Polymers (PEEK/PMMA) and Conventional PMMA Materials: An In Vitro Study

Abstract

The present study aims to investigate the mechanical properties of base materials [polymethyl methacrylate (PMMA)/polyether ether ketone (PEEK)] fabricated with computeraided design/computer-aided manufacturing (CAD/CAM) and heatpolymerized conventional base materials. Material and Methods: Two different base polymers milled with CAD/CAM (Yamahachi PMMA Disk and Juvora Dental Disk PEEK) and heat-polymerized acrylic resin (Meliodent PMMA) were used in this study. A total of 120 specimens were prepared with 10 specimens in each subgroup of the test materials. Half of the test specimens were stored in distilled water, while the other half were subjected to a thermal cycle. After the thermal cycle, the flexural strength, elasticity module, and, surface hardness of all test specimens was evaluated. The Mann-Whitney U and Kruskal-Wallis tests were used in the analysis of the data. Results: According to the findings of flexural strength and elasticity module of the test specimens, the highest to lowest value ranking was as follows: CAD/CAM PEEK>CAD/CAM PMMA>heat-polymerized PMMA. In the PMMA group produced with CAD/CAM, surface hardness values were significantly higher in the thermocycle applied test specimens compared to those stored in distilled water (p<0.001). Conclusion: CAD/CAM PMMA and PEEK materials were compared with the heat-polymerized test specimens found to show better mechanical properties.

Patient satisfaction and oral health‐related quality of life for four implant‐assisted mandibular overdentures fabricated with CAD/CAM milled poly methyl methacrylate, CAD/CAM‐milled poly ether ether ketone, or conventional poly methyl methacrylate: A crossover clinical trial

“…Also, many authors explained that the CAD/CAM milling technique uses exceptionally dense prepolymerised resin pucks that were built under high pressure and temperature; hence, the resulted dentures have a low monomer content and improved mechanical qualities even in thinner portions, as well as superior denture retention, adaptation and postinsertion complaint. These advancements raise patient happiness and comfort 34,76 …”

“…33 The optimised mechanical properties of PEEK are attributed to the special ceramic filler with very small grain size (0.3-0.5 μm) and a constant homogeneity. 34 PEEK has unique propriety as its modulus of elasticity is similar to the elasticity of bone. 35 Poly ether ether ketone is used as a framework material for removable dental prosthesis, 36 tooth-implant-supported and implantsupported bridges 37 and denture base material for implant retained or supported overdentures to preserve the implant-supporting structures.…”

“…These advancements raise patient happiness and comfort. 34,76 The length of the treatment and the diminished need for modifications, maintenance and follow-up visits may be factors encourage the rehabilitated patients to recommend this treatment to the family and friends. 76 On the contrary, the follow-up for traditional complete dentures begins after the first 24 h of denture insertion.…”

“…PEEK is strongly recommended as an alternative to commonly used dental materials for restorations and the production of base structures through CAD/CAM 33 . The optimised mechanical properties of PEEK are attributed to the special ceramic filler with very small grain size (0.3–0.5 μm) and a constant homogeneity 34 . PEEK has unique propriety as its modulus of elasticity is similar to the elasticity of bone 35 …”

Flexural Behavior of Biocompatible High-Performance Polymer Composites for CAD/CAM Dentistry

“…They also offer great esthetics [19]. Data regarding these polymeric materials' flexural behavior in response to intraoral stresses are scarce [24]. This is partly due to their relatively recent introduction to dental restoration's digital fabrication.…”