Isolating a deep root decay prep is challenging. This is only the beginning. You must also construct a tight contact while bridging a wide interproximal gap.
Deep sub gingival Class II prep which typically results in a wide embrasure space. I reshaped the gold on the mesial of #18 to a more ideal contact surface.
Greater Curve band trimmed
The Greater Curve Standard was trimmed at the mesial. This will allow the band to seat apically past the deep distal margin.
Greater Curve in place
Greater Curve in place. Distal contact opening made. Note the contact opening is not fully against the contiguous #19. There is an unwanted gap at the base. The entire periphery of the contact opening should be in intimate contact with the contiguous tooth. If it isn’t, composite will pass through and lock in the matrix.
Flowable composite placed
Flowable composite is placed along the cervical floor (SureFil SDR flow) Contact opening is secured with a condenser while my assistant cures the flowable.
Contact opening is now up against the contiguous tooth. You can see the cured composite dimple left by the condenser. See arrow.
This view shows the retainer arm being elevated by Blu-Mousse. Elevating the retainer arm pushes the band distally against the neighboring tooth.
Final Class II composite
Final Class II composite (SonicFil) crafted on a short tooth with deep subgingival decay and a wide embrasure.
1) A contact with depth is an integral part of the Greater Curve technique. A contact with depth enables the dentist to shape a rounded marginal ridge without fear of adjusting through the contact.
2) A matrix can more easily extended across a wide space when there is no wedge blocking the way.
3) Had an excellent seal against contamination. The Greater Curve band draws very tight round the base of the tooth in spite of the prep margin being subgingival.