Background. The authors present a technique for placing and reinforcing an amalgam matrix around combined Class II and Class V preparations that connect at the proximal box.
Overview. First, the dentist fills the Class V aspect of the preparation, using a temporary resin-based composite wall at the line angle to support amalgam condensation. The dentist then removes the wall and places a matrix band around the tooth, internally reinforcing the band with smaller pieces of matrix band and resin-saturated cotton balls that are light-polymerized and externally reinforcing the band with fast-polymerizing vinyl polysiloxane. Finally, the dentist condenses the line angle amalgam through the proximal box and condenses the proximal box and occlusal aspects.
Conclusion. For connected Class II and Class V preparations, this matrix technique permits controlled amalgam condensation, even at the line angle aspect, where it is difficult to condense amalgam without voids or microleakage.
Clinical Implications. This technique allows dentists to provide a stable, inexpensive direct restoration for teeth with connected Class II and Class V preparations, providing an alternative for patients who do not wish to have crowns placed.
