How the Build Angle Affects the Marginal and Internal Fit of
3D
Printed Definitive
FPDs
: An in Vitro Study
Bora Akat, Bahar Kavafoğlu Yilmaz, Fehmi Gönüldaş, Mert Ocak, Stephen F. Rosenstiel, Evşen Tamam ABSTRACT
Statement of Problem
Printing parameters may influence the fit of additively manufactured dental restorations. However, the effect of small incremental build angles on the marginal and internal fit of stereolithography (SLA)‐printed definitive 3‐unit fixed partial dentures (FPDs) has not been sufficiently investigated.
Purpose
The purpose of this in vitro study was to evaluate the effect of small incremental build angles (0°, 10°, 20°, and 30°) on the marginal and internal fit of SLA‐printed definitive 3‐unit FPDs.
Material and Methods
A typodont maxillary first premolar and first molar were prepared to serve as abutments for a 3‐unit FPD. After digital scanning, restorations were designed using dental CAD software and fabricated from a definitive resin using an SLA printer. Forty FPDs were produced at four different build angles (0°, 10°, 20°, and 30°) ( n = 10). Marginal and internal fit were evaluated using microcomputed tomography. Gap measurements were obtained at five reference points for each abutment. Data were analyzed using one‐way analysis of variance followed by Tukey honestly significant difference post hoc tests ( α = 0.05).
Results
Build angle significantly affected the marginal and internal fit ( p < 0.05). For both molar and premolar supports, the highest fit was achieved with 30°, followed by 20°. Differences between 20°–30° and 0°–10° were not statistically significant ( p > 0.05). The marginal discrepancy was higher than the internal discrepancy.
Conclusions
Within the limitations of this in vitro study, build angle influenced the marginal and internal fit of SLA‐printed 3‐unit FPDs. Among the orientations tested, the 30° build angle generally produced the smallest gap values.