Biological Safety of 3D Printing Materials Based on Acrylic Resins Used in Dentistry: Narrative Review

Aim: This literature review presents the biological evaluation of light-curing 3D printing materials containing methacrylic and acrylic resin in dentistry. The sample was 42 articles published between 2008 and 2025, available on PubMed, Scopus, Cochrane, and Google Scholar. The articles were analyzed following the assessment requirements of ISO 10993-2018 (Endpoint) regarding the biological evaluation of each Medical Device. The first selection criterion of the articles was based on the PRISMA schema, concerned with the application of these materials in various fields of dentistry used in 3D printing (e.g., material for crowns and bridges, night, and surgical guide, orthodontic, and denture base). The second criterion included the composition of materials (e.g., catalysts, methacrylic resins, and stabilizers) and the post-curing process. Results: The topics discussed in the literature included: (a) estrogenic interactions, sensitization, and the zebra fish model to determine acute toxicity; (b) the main post-processes affecting biocompatibility, i.e., alcohol washing and polymerization in light ovens; and (c) the modification of 3D resins using various types of nanomaterials. Conclusions: 3D resins can be used safely in dentistry to make various types of restorations, provided that the polymerization, washing with alcohol and post-polymerization in a light oven follow the manufacturer's specifications.