What is the primary purpose of using a wedge during a restoration?

The primary purpose of using a wedge during a restoration is to aid in the adaptation of the matrix band. The wedge is employed to hold the matrix band tightly against the tooth structure, which is crucial for achieving a proper contour and ensuring that the restorative material is adequately confined within the prepared cavity. This tight fit helps in creating a seamless interface between the restoration and the natural tooth structure, ultimately improving the quality of the final restoration.

Additionally, by securing the matrix band in place, the wedge helps to prevent the restorative material from flowing beyond the desired margins during the filling process, thereby contributing to better overall accuracy in the final outcome. While aspects such as creating a good marginal seal and interproximal contact contour are important, the wedge's primary role is to effectively ensure that the matrix band is correctly adapted to the tooth.