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A Comparison of the Flexural and Impact Strengths and Flexural Modulus of CAD/CAM and Conventional Heat‐Cured Polymethyl Methacrylate (PMMA)

The introduction of CAD/CAM technology to the field of removable prosthodontics has recently made it possible to fabricate complete dentures of prepolymerized polymethyl methacrylate (PMMA) blocks, which are claimed to be of better mechanical properties; however, no published reports that have evaluated mechanical properties of CAD/CAM PMMA. The purpose of this study was to compare flexural strength, impact strength, and flexural modulus of two brands of CAD/CAM PMMA and a conventional heat‐cured PMMA. ResultsThe CAD/CAM PMMA showed the highest mean flexural strength (130.67 MPa) and impact strength (29.56 kg/m2). The highest mean flexural modulus was recorded in the AvaDent group (2519.6 MPa). The conventional heat‐cured group showed the lowest mean flexural strength (93.33 MPa), impact strength (14.756 kg/m2), and flexural modulus (2117.2 MPa). As CAD/CAM PMMA specimens exhibited improved flexural strength, flexural modulus, and impact strength in comparison to the conventional heat‐cured groups, CAD/CAM dentures are expected to be more durable.

                                              

--《Journal of Prosthodontics》2020.