Shear Bond Strength Between Artificial Teeth and Denture Base Resins Fabricated by Conventional, Milled, and 3D-Printed Workflows: An In Vitro Study.

BACKGROUND: The adhesion between artificial teeth and denture bases is crucial for the longevity of complete dentures. This in vitro study evaluated the shear bond strength (SBS) and failure modes between artificial teeth and denture base resins produced with conventional, milled, and 3D-printed techniques. MATERIALS: A total of 105 specimens were fabricated and assigned to 7 groups (n = 15) combining conventional, milled, or printed denture bases with conventional, milled, or printed teeth. SBS was tested using a universal testing machine, and failure modes were classified as adhesive, cohesive, or mixed. Data were analyzed with one-way ANOVA and Tukey's post hoc test (α = 0.05). RESULTS: SBS significantly varied among groups (p < 0.001). The conventional base-conventional tooth group (CB-CT) showed the highest bond strength (14.9 ± 3.69 MPa), while the printed base-milled tooth group (PB-MT) had the lowest (6.58 ± 3.41 MPa). Milled base groups showed intermediate values (11.7-12.4 MPa). CONCLUSIONS: Bond strength between denture teeth and denture bases depends on the fabrication workflow. Conventional heat-cured PMMA bases exhibited the most reliable adhesion, while milled bases demonstrated satisfactory performance with optimized bonding. Printed bases showed reduced and variable adhesion, suggesting the need for improved bonding protocols before their widespread clinical application in definitive prostheses.