Which instrument is used to hold the matrix band during dental procedures?

The matrix retainer, often referred to as a Tofflemire retainer, is specifically designed to hold the matrix band in place during restorative dental procedures, such as the placement of fillings. This instrument allows the dentist to create a temporary wall that mimics the natural tooth structure, providing support for the filling material and helping to shape it correctly. The matrix band itself is a thin strip of metal or plastic that wraps around the tooth, and the retainer securely holds this band to enable accurate restoration of the tooth's contour and function.

In the context of dental procedures, the other options do not serve this purpose. A curing light is used for hardening dental materials, a micro brush is utilized for applying small amounts of dental materials or medications, and a burs bur block is used for organizing and holding dental burrs, which are tools used for cutting or shaping tooth structure. None of these instruments provide the necessary support for a matrix band during restorative work, confirming the effectiveness and importance of the matrix retainer in dental practice.