The sectional matrix is primarily used with which accessory to establish proximal contacts during a posterior restoration?

• A. Wedges
• B. Tofflemire matrix
• C. Shade guide
• D. Acid etch

Answer: (A)

Wedges are used with sectional matrices to create and stabilize a tight proximal contact during posterior restorations. The sectional matrix provides the contoured band, but without a wedge, the matrix may not seat firmly against the tooth or may pull away, leading to an open contact or overhang. Inserting a wedge into the interproximal space applies lateral pressure, seating the matrix snugly against the tooth surfaces, and slightly separating adjacent teeth to shape a proper contact point. This combination is what allows the restoration material to be confined and contoured to form an intact proximal contact.

Shade guides and acid etch serve coloring and bonding steps, not to establish contacts, and the Tofflemire matrix is a different system not used with sectional matrices in this context.