Orthodontic appliance structure and materials

Invisible aligners are made of elastic, transparent polymer materials, eliminating the wires and brackets of traditional braces and offering a high level of aesthetics. The materials are typically made of medical-grade polyurethane or polycarbonate, with a thickness of approximately 0.5-1.5 mm, possessing good biocompatibility and mechanical properties. Common materials for fully invisible aligners include polymers, polycarbonate, polyurethane, thermoplastic polyurethane elastomers, and medical-grade silicone. These materials need to possess characteristics such as high transparency, good toughness, close fit to teeth, and provision of continuous corrective force. Different materials have different characteristics in terms of hardness, elasticity, wear resistance, and comfort, suitable for different cases and patient needs.

Specific brands may use patented materials; for example, Invisalign uses the patented SmartTrack material, while Angelalign uses the next-generation medical-grade polymer material MasterControl.