How the Build Angle Affects the Marginal and Internal Fit of 3D Printed Definitive FPDs: An in Vitro Study

Area of Science:

• Additive Manufacturing
• Dental Materials Science
• Biomaterials Engineering

Background:

• Printing parameters significantly impact the fit of additively manufactured dental restorations.
• The influence of incremental build angles on stereolithography (SLA)-printed 3-unit fixed partial dentures (FPDs) remains under-investigated.

Purpose of the Study:

• To evaluate the effect of varying build angles (0°, 10°, 20°, 30°) on the marginal and internal fit of SLA-printed definitive 3-unit FPDs.
• To determine the optimal build orientation for achieving superior fit in SLA-printed FPDs.

Main Methods:

• Forty 3-unit FPDs were fabricated using SLA printing at four build angles (0°, 10°, 20°, 30°).
• Marginal and internal fit were assessed using microcomputed tomography (micro-CT) by measuring gap discrepancies at predefined points.
• Statistical analysis involved one-way ANOVA and Tukey's post hoc tests.

Main Results:

• Build angle significantly influenced the marginal and internal fit of the FPDs (p < 0.05).
• The 30° build angle demonstrated the highest fit, followed closely by the 20° angle.
• Marginal discrepancies were generally larger than internal discrepancies.

Conclusions:

• Build angle is a critical parameter affecting the marginal and internal fit of SLA-printed 3-unit FPDs.
• A 30° build angle is recommended for optimizing the fit of these dental restorations when using SLA printing.