- Dental materials are evaluated based on their physical, mechanical, and biological properties.
- Biological properties refer to how the material interacts with the living tissues in the oral environment.
- This includes the material’s ability to be non-toxic, non-irritating, and non-allergenic to the patient, ensuring it does not cause any harmful effects when placed in the mouth.

- In contrast, thermal conductivity (Option 1), tensile strength (Option 2), and elastic modulus (Option 4) are examples of physical and mechanical properties.
- These describe how the material behaves under physical forces or temperature changes but do not relate to its biological compatibility with oral tissues.

Therefore, biocompatibility is the characteristic that describes a biological property of dental materials.

Reference: Craig’s Restorative Dental Materials, 13th Edition, Chapter 3: Biological Properties of Dental Materials