Exothermic properties of polyurethane casting materials.

Area of Science:

• Orthopaedic materials science
• Biomedical engineering
• Clinical application of casting materials

Background:

• Orthopaedic casting materials generate exothermic heat during application.
• Understanding heat generation is crucial for patient safety and preventing thermal injury.
• Variations in exothermic properties among different casting materials necessitate comparative analysis.

Purpose of the Study:

• To compare the exothermic properties of three leading orthopedic casting materials: Delta Lite S, Dynacast Extra, and Scotchcast Plus.
• To investigate factors influencing the maximum temperature generated beneath these casts.
• To assess thermal behavior in both laboratory and simulated 'in use' conditions.

Main Methods:

• Casting materials were applied to a model leg using varying numbers of turns (four, five, or six).
• Temperature beneath the cast was measured at five-second intervals over a 10-minute period.
• Exothermic properties were also assessed by measuring the maximum temperature increase in water and water uptake during activation.

Main Results:

• Dynacast Extra exhibited higher temperatures compared to Delta Lite S and Scotchcast Plus in laboratory tests.
• Despite higher temperatures, Dynacast Extra did not produce damaging heat levels when manufacturer instructions were followed.
• No significant differences in temperature were detected when casts were applied to a volunteer (in vivo).

Conclusions:

• The risk of thermal damage from orthopedic casting materials can be minimized by adhering to manufacturer guidelines.
• Careful application techniques and awareness of material properties are essential for safe cast application.
• The study provides recommendations for the safe usage of these orthopedic casting materials.