What is a characteristic of biting registration materials like wax?

Biting registration materials, such as wax, are designed to be stiff and unyielding once they have set. This characteristic is crucial because it allows for an accurate recording of the occlusion or bite relationship between the upper and lower jaws. A stiff material provides stability, ensuring that the registration remains unchanged during manipulation or during the process of making dental impressions.

When materials are fluid, as suggested in one of the other choices, it can lead to distortion and inaccurate readings, as they may change shape under pressure or movement. Heating wax before use is not typically required as many types of biting registration waxes are designed to be used in their manufactured form, eliminating the need for pre-heating. Additionally, while some materials might provide less detail, wax is often sufficient for registration purposes, so claiming it provides little detail does not align with its intended use which focuses on capturing the bite.