ABSTRACT
Aim: The aim of this study was to evaluate efficacy of build direction of 3D printing full coverage provisional restoration on the marginal integrity
Materials and methods: The prepared resin tooth was scanned and single crown was designed using computer-aided design (CAD) software. Provisional crowns were printed using a SLA-based 3D printer at 2 directions vertical (120°) and horizontal (180°) with 16 crowns in each direction. In total, Thirty two crowns were printed. To measure the marginal gap using USB Digital microscope, then morphometric measurements were done for each shot [3 equidistant landmarks along the cervical circumference for each surface of the specimen (Mesial, buccal, distal, and lingual), and a silicone replica was fabricated for measuring internal fit, the replicas were carefully sectioned into four equal segments.
From the four sections obtained from each replica, two opposite sections were used to measure internal fit, with five regions measured on each section (finish line, axial wall and occlusal), yielding 10 internal measurements for each coping and the thickness of the silicone impression material was measured using a digital microscope.
Results: Vertical Marginal Gap it was found that horizontal group recorded statistically significant higher marginal gap mean value (44.76 µm) than vertical group (34.37 µm) as indicated by t-test (P=0.0002<0.05), considering internal fit regardless to measurement site, totally there was non-significant difference between both groups vertical group (96.042 µm) and horizontal group (91.793 µm) as indicated by two-way ANOVA test (p=0.6179 > 0.05) where (vertical group > horizontal group)