Mechanical and Physical Properties of Zendura Flx™ after One and Two Weeks of Thermoformed Aligner Therapy: A Prospective Clinical Study

Abstract Background: The utilization of clear aligners (CA) has increased owing to esthetic demands. Objective: The objective of this study was to evaluate alterations in the mechanical properties, surface morphology, and the translucency parameter of Zendura Flx TM (ZF) following 1 week (1W) and 2 weeks (2Ws) of intraoral usage. Materials and Methods: Forty-eight ZF aligners were selected (Bay Materials, USA). CAs were divided into three groups ( n = 16); control group of unused ZF, intraorally aged groups (1W and 2Ws). All samples underwent tensile and indentation testing, surface morphology, and translucency evaluations. Tensile resistance was measured by the Universal Testing Machine. Surface microhardness was determined using Digital Vickers micro hardness tester. Surface topography was characterized using a digital microscope. Spectrophotometry was used to evaluate changes in transparency. Results: A statistically significant difference was seen in the mean tensile resistance across the three groups ( P = 0.033). The 2W group exhibited a substantial increased tensile resistance. No significant changes were observed regarding other assessed properties. Conclusion: ZF demonstrated commendable tensile resistance, consistent hardness, surface topography, and transparency after physiological intraoral aging indicating its suitability for usage over 1–2 weeks.