What is a sectional matrix most often used for?

A sectional matrix is primarily used for Class II restorations, which involve the proximal surfaces of posterior teeth, typically where decay has occurred between two adjacent teeth. The design of the sectional matrix allows for proper adaptation and a snug fit around the tooth structure, which is essential for achieving a tight contact point with the adjacent tooth. This is particularly important in Class II restorations to ensure that the restoration not only fills the cavity but also maintains the integrity of the contact area, providing proper interproximal contact once the restoration is completed.

Sectional matrices come in a variety of shapes and sizes and are secured to the tooth with a small wedge, creating a tight seal that helps to prevent overflow of the restorative material. They are especially beneficial in achieving a smooth, contoured surface that mimics the natural anatomy of the tooth. Hence, their primary application in Class II restorations distinguishes them from other classes of restorations, which typically do not require the same level of interproximal precision.