Thermoplastic
A category of polymer materials used in orthotic fabrication that can be repeatedly softened by heating and hardened by cooling, allowing custom moulding directly over a patient's body segment or cast.
Full Definition
Thermoplastic materials are a cornerstone of custom orthotic fabrication; when heated to a specific temperature range, they become pliable and can be draped, moulded, or vacuum-formed over a plaster positive model or directly onto the patient, retaining their shape upon cooling. Common thermoplastics used in orthotics include polypropylene, polyethylene, and Kydex. Editors reviewing orthotic clinical or technical documents should note that 'thermoplastic' refers to the material class, not a specific product, and should not be italicised or treated as a trade name. It is important not to confuse thermoplastic with 'thermoset' materials, which cannot be remoulded after initial curing. In patient-facing materials, the term 'plastic' is often used colloquially; formal documents should use 'thermoplastic' with the specific material named where known.
Usage
Usage note: Specify the polymer type (e.g., polypropylene, polyethylene) alongside 'thermoplastic' wherever the source document provides this information.
In Context
- "The AFO was fabricated from polypropylene thermoplastic and trimmed posteriorly to allow partial dorsiflexion assist." — Orthotic fabrication specification
- "Editors should not italicise 'thermoplastic' as it is not a trade name but a material category; the specific polymer should be named when known." — Editorial style guide