Effect of Print Angulation on Surface Roughness of 3D-Printed Models.

Additive manufacturing processes are increasingly being used in dentistry. The underlying process is the polymerization or fusion of material layer by layer to create layer lines on the final printed surface. How print orientation affects these layer lines is unclear. The primary objective of this research was to measure and compare the surface waviness and surface roughness of maxillary models fabricated using a variety of 3D printers and resin types, and to evaluate the effect of different print angulations. The same STL file was used to manufacture 48 models using a variety of resins and printers at 0 degrees, 30 degrees (with base supports), and 70 degrees ("vertical" without supports) to the build plate. Six replications with each angulation were printed. All samples were optically scanned with a laser profilometer and compared. The results indicated that print angulation can significantly affect the surface roughness of 3D-printed objects, but the results seemed to be specific to the resin/printer products and angles. The authors concluded that surface waviness values should be considered whenever surface smoothness is evaluated.