What is the advantage of using sectional matrices over circumferential matrices for composite restorations? A circumferential matrix placed in a Tofflemire retainer is necessary for placing an amalgam restoration. The reason is that amalgam is forcefully condensed against the matrix band and it needs to maintain a tight seal against... What is the advantage of using sectional matrices over circumferential matrices for composite restorations? A circumferential matrix placed in a Tofflemire retainer is necessary for placing an amalgam restoration. The reason is that amalgam is forcefully condensed against the matrix band and it needs to maintain a tight seal against...