Micro-CT evaluation of aligner fit and thickness in 3D-printed and thermoformed aligners: Differences in relation to inner-surface offset design and tooth regions

Objective: To assess the adaptation and thickness of three-dimensional (3D)-printed and thermoformed aligners, comparing differences in relation to fabrication methods, inner-surface offset, and tooth region. Methods: tests. Results: < 0.001). Conclusions: A 0.05-mm offset in 3D-printed aligners produced gap values comparable to those obtained with thermoformed aligners and showed consistent adaptation over tooth regions. 3D-printed aligners tended to show greater thickness than their virtual design, whereas thermoformed aligners showed reduced thickness.