Avaliação das propriedades de resinas utilizadas em impressão 3D na Odontologia: uma revisão sistemática e um estudo laboratorial

Abstract

Traditional methods of manufacturing occlusal splints using polymethyl methacrylate (PMMA) resins are gradually being replaced by photosensitive resins adapted for 3D printing, providing a more efficient and customized alternative. Among the 3D printing technologies, stereolithography (SLA) and digital light processing (DLP) stand out, with the spread of low-cost SLA/LCD-based printers, access to additive manufacturing is expanding. This study was conducted in two phases. In the first, a systematic review was performed to evaluate the physical, mechanical and biological properties of photosensitive resins for the manufacture of occlusal splints, comparing them with PMMA resins. The review of laboratory studies revealed that, in general, PMMA presented better performance, especially in properties such as fracture resistance and durability in the meta-analysis. This study demonstrated that photosensitive resins used in 3D printing for occlusal splints generally exhibited inferior physical, mechanical and biological properties compared to conventional PMMA materials. In the second phase, an experimental study was conducted with three photosensitive resins (Cosmos Splint, NextDent OrthoRigid, and Prizma BioSplint) printed with an affordable LCD printer, comparing them with thermosetting and self-curing PMMA. The results indicated that the photosensitive resins showed good flexural strength and lower water absorption, but some showed lower strength and hardness than PMMA. Cell viability varied, with some resins showing cytotoxic performance after 14 days. Photosensitive resins, although they do not completely outperform PMMA and may not have as long-lasting strength, may be a promising and faster alternative for the fabrication of occlusal splints.