Removal of Remaining Carious Dentin and Defective Restorations

It is important to remove the caries and defective restorations in an endodontic cavity for three reasons:

1) To eliminate mechanically as many bacteria as possible from the interior of the tooth.

2) To eliminate the discolored tooth structure, that may ultimately lead to staining the crown.

3) To eliminate the possibility of any bacteria-laden saliva leaking into the prepared cavity (especially for proximal or buccal caries that extend into the prepared cavity).

After caries removal, if the carious perforation of the wall is allowing salivary leakage, the area must be repaired with cement, preferably from the inside of the cavity. If the caries is so extensive that the lateral walls are destroyed, or if the defective restoration is in place that is loose and leaking, then the entire wall or restoration should be removed and later restored. It is important that the restoration be postponed until the radicular preparation has been completed. It is much easier to complete the radicular preparation through an open cavity than through a restored crown. As long as a rubber dam can be placed on the tooth, it need not be built-up with amalgam, cement, or a copper band. If enough tooth does not remain above the gingiva to place a rubber dam clamp and seal against saliva, and if it is imperative that the tooth be retained, a simple gingivoplasty will establish the required “crown” length.