Conservative Amalgam Replacement and Class I Restoration
Fiber mesh and fiber-reinforced composite help manage material and tooth stresses
Jihyon Kim, DDS
For direct restorations, the use of composite resin far exceeds that of amalgam. However, retentive cavity preparations that are more ideally suited for amalgam persist. Retentive preparations may result in the excess removal of sound tooth structure, which can contribute to damaging tooth flexure. In addition, the high C-factor geometry of retentive preparations is problematic for dentin adhesion and may lead to debonding, sensitivity, and premature failure. When sound adhesive principles are understood and applied, the use of fiber mesh or a fiber reinforced composite can play a significant role in managing material and tooth stresses.
The figures present two cases featuring Class I restorations. The first case involves retreatment of a properly executed amalgam restoration with cuspal fracture—a common clinical scenario. Although conventional treatment usually entails placement of an indirect restoration, a stress-reduced direct composite restoration can be a predictable option if proper adhesive techniques are employed. A fiber mesh was used to mitigate the stresses associated with composite polymerization shrinkage and to function as a fail-safe for the compromised tooth.
In the second case, a conservative intervention is employed to restore moderate occlusal caries. Instead of utilizing strict G.V. Black preparation designs, the caries was removed in a manner in which the sound occlusal tooth structure was maximally preserved in order to mitigate potentially damaging tooth flexure under load. A fiber reinforced composite material was used in the restoration to help manage the shrinkage stresses in this conservative preparation.
About the Author
Jihyon Kim, DDS
Seattle and Bellevue, Washington