Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE Glass and carbon fibers are incorporated into a polymerized PMMA matrix to improve the mechanical performance of temporary dental prostheses. The reinforced composites exhibit greater flexural strength, tensile strength, and modulus of elasticity due to efficient load transfer at the fiber-matrix interface. Reinforcement with short fibers emerges as a simple and effective strategy to increase the structural reliability of PMMA prosthetic materials.

ABSTRACT
Poly(methyl methacrylate) (PMMA) is used in temporary dental prostheses; however, its high stiffness and brittle fracture behavior often lead to failures under masticatory loading, compromising patient comfort and osseointegration in implant-supported treatments. In this study, short glass and carbon fibers (3 and 5 mm) were incorporated into a thermopolymerizable PMMA matrix at volumetric fractions of 1%, 2.5%, and 5% to improve its mechanical and viscoelastic performance. Flexural and tensile tests, dynamic mechanical thermal analysis (DMTA), and scanning electron microscopy (SEM) evaluated the influence of fiber geometry and reinforcement content on the structure–property relationship of the composites. Compared to neat PMMA, all reinforced formulations showed improved mechanical performance. Carbon fiber incorporation increased flexural strength from 91 to 121 MPa and tensile strength from 32 to 51 MPa, while glass fiber reinforcement increased flexural strength from 90 to 115 MPa and tensile strength from 34 to 50 MPa. Dynamic mechanical thermal analysis revealed increased storage modulus and reduced tan δ intensity, indicating restricted molecular mobility. Scanning electron microscopy confirmed adequate fiber–matrix adhesion. Overall, short fiber reinforcement improved the structural reliability and thermomechanical stability of PMMA for temporary dental prostheses.