Clinical evaluation of the direct composite resin restorations on nonvital teeth ：A clinical report of 8 cases

Abstract

The composite resin materials have been indispensable for restoring the carious hard tissues of vital teeth after a lot of improvements. Compared to the vital teeth, the nonvital teeth are less resistant to external load because their sound substances have been partly removed by the root treatment besides the essentially decreased strength. It is, therefore, general that they are indirectly restored with the material stronger than the tooth substance for functional recovery. However, it is worried that the residual tooth substance may be fractured when a heavy load is applied by mastication or trauma. Root fracture may lead to the loss of tooth. Unlike the indirect restoring, the direct restoring needs little grinding of the residual tooth substance and it is expected that the composite resin showing good affinities in adhesiveness and physical properties to the tooth substance may be united with the tooth to reinforce the residual tooth substance. Although such a usefulness of the composite resin has been recognized in the direct restoring of the nonvital tooth, there are few clinical reports and clear judgments on its indication. On the other hand, the needs (problems) of the patients become diversified with the change of society and it is necessary to prepare multiple options for solving solution against each single clinical condition. In the present report, the cases of the direct restoring of the nonvital teeth with the composite resin were followed up as considering the various problems of the patients and the methods for the functional recovery of the nonvital teeth were evaluated. The results obtained were as follows: The direct restoring technic with the composite resin for nonvital teeth showed good performance in which the restored teeth were conserved keeping ordinal functions in spite that the number of followed-up patients might be small (8 cases) and the following-up period not sufficiently long in some cases. The failures observed during the following-up period were well corresponded by repair with the composite resin. It was suggested that the direct restoring with the composite resin was useful for recovering function of the nonvital teeth.