Influence of Printing Angle on The Physico-Mechanical Properties of PMMA-Based Resins for Dental Use: A Systematic Review of in Vitro Studies.

Purpose: To investigate the influence of printing angle on the physico-mechanical properties of PMMA.

Material and methods: This systematic review included the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA 2020) and was registered with the Open Science Framework (osf.io/y4qm8). Electronic searches were carried out in the PubMed/Medline, Scielo, Scopus, Embase and Science Direct databases. Risk of bias was analyzed using the Joanna Briggs Institute (JBI) instrument for quasi-experimental studies.

Results: Of the 1917 studies identified, 25 were included and qualitatively assessed after the selection stages. Printing dental devices for prosthetic use in PMMA-based resins provides satisfactory performance, with better resistance to bending and fracture at 0°. After polishing, the differences observed in surface roughness concerning the printing angle became insignificant. The different printing angles can influence the optical properties significantly, but other factors such as the composition of the resin can influence these results.

Conclusion: Printing dental devices in PMMA-based resins provides satisfactory performance for prosthetic use. In general, better mechanical performance was attributed to 0° compared to 45° and 90°. Varying the printing angle can be a strategy for individualizing prosthetic devices according to the physical and mechanical needs presented by each type of clinical application.