Wedges for protection of rubber dam

When using a rubber dam whilst preparing an interproximal cavity, apply some interdental wedges before the box prep to retract and protect the rubber dam as well as to separate the teeth to allow easier breakage of the contact.

When using floss to take the interseptal dam under the contact, the dam should have the leading edge at the occlusal aspect of the contact point. i.e the septa of the dam should not be unched up and a single thcikness of the dam should pass through the contact at any point. If one floss through is enough to bring the whole dam down, lift the lingual end of the floss over the contact point and to the facial so that when you are pulling the floss out at the facial there is no contact with the papilla that may cause trauma. If multiple flosses are needed, bring the lingual end of the floss to the facial and refloss through the contact without removing the first strand of floss.

The dam should be inverted around the necks of the teeth, at least in the area of the tooth or teeth to be restored. The edge of the dam that is against the tooth acts as a valve. If the edge is directed occlusally, when a positive pressure is created by the tongue and cheeks under the dam, the valve opens, and saliva and other liquids under the dam are pushed between the tooth and dam to flood the operating field; then, when a negative pressure is created under the dam, the valve closes and the saliva is trapped in the field. When the dam is inverted, a positive pressure under the dam simply serves to push the valve more tightly against the tooth so that no flooding of the field occurs.