Flexural strength of denture bases manufactured by digital techniques compared to conventional heat-polymerized: a systematic review

Total tooth loss results in significant physical, aesthetic, and psychosocial impacts, with prosthetic rehabilitation being the most common solution. The material widely used for denture bases is heat-polymerized acrylic resin, but it has limitations. With the advancement of digital techniques, such as CAD/CAM (computer-aided /computer-aided manufacturing) and 3D printing, there is an opportunity to improve prosthesis manufacturing. This study aims to compare, through a systematic review, the flexural strength of denture bases fabricated using digital techniques (CAD/CAM and 3D printing) and conventional methods (heat-polymerized). Following the PRISMA methodology and applying the PICO (Population, Intervention, Comparison, and Outcome) criteria, complete in vitro studies evaluating flexural strength using ISO (International Standards Organization) / ADA (American Dental Association) standardization were included. The review selected 11 studies for analysis. The findings indicated that dentures milled with CAD/CAM showed higher flexural strength compared to those produced by 3D printing and heat-polymerization. Although 3D printed material exhibited lower strength, it showed increased values when subjected to longer polymerization times. The digitally printed technique demonstrated satisfactory values, even though they were generally lower than those of the conventional heat-cured method. Milled PMMA stood out in terms of strength compared to other materials. Further research is needed on the applicability of 3D-printed material for dentures and clinical studies to assess the material’s performance in the oral cavity.