Aim: to assess the effect of different materials and techniques of surface treatment
on the flexural strength of repaired 3D-printed denture base. Subjects and
Methods: A total of 150 specimens were printed on a 3D printer in a rectangular shape
in dimensions 65×10×2mm. The flexural specimens were 10 groups (n=15). Each
specimen was sectioned in the middle into two halves. Group 1 (control), the first
three groups repaired with 3D denture base resin using surface treatment of Monomer,
Sandblasting, and a combination of both respectively. The second three groups repaired
with heat-polymerized polymethyl methacrylate (HPA) using surface treatment of
Monomer, Sandblasting, and a combination of both respectively. And last three groups
repaired with Auto-polymerized polymethyl methacrylate (APA) using surface treatment
of Monomer, Sandblasting, and a combination of both respectively. The flexural
strength was measured using a universal testing machine. Statistical analysis was
done using one-way ANOVA test and Tukey's post-hoc test (α=.05). Results: The
groups repaired with 3D denture base resin was significantly the highest mean flexural
strength. Mechanical surface treatment was significantly the highest mean flexural
strength in every repaired material. Conclusions: The 3D denture base resin is the material
of choice for repairing fractured 3D dentures followed by (HPA) and then (APA).
Mechanical surface treatment is recommended for repairing 3D dentures.