Herbert T. Shillingburg

Restoration of endodontically treated posterior teeth

Abstract A comprehensive scheme has been presented for the restoration of endodontically treated teeth. A technique for making cast gold dowel-cores from direct acrylic resin patterns has been described. The method can be used for mutilated teeth with favorable root forms. An alternate method, the pin-retained amalgam core, can be used for teeth needing extensive restorations but which lack favorable root size and shape.

Retention and resistance of preparations for cast restorations

Five preparation designs were tested for retention and resistance. Retention values for all partial veneer crowns were significantly lower than those for the complete veneer crown. Resistance values increased significantly with the addition of grooves and/or extension of axial surface coverage. Addition of grooves and/or extension of axial surface coverage produced small increases in retention values but marked increases in resistance values.

Porcelain fused to metal: Tooth preparation and coping design

Abstract A brief history of the development of the currently popular porcelain-fused-to-metal restoration has been presented. A tooth preparation design has been described with labial reduction of 1.2 mm. done in two planes to allow a bulk of porcelain for esthetic appeal while protecting the integrity of the pulp. A beveled shoulder finish line is advocated on the labial to aid in minimizing distortions which can occur during the fabrication of the restoration. Occlusal contact on metal is recommended, especially for posterior teeth. A bridge design has also been presented, with an exposed metal strip on the lingual and a small pontic tissue contact in porcelain.

Articulator selection for restorative dentistry

There are many types of articulators that can be used for making fixed restorations. While unquestionably the most accurate, the fully adjustable instrument is not feasible or necessary for many forms of simple occlusal treatment. The effects of tooth-hinge axis radius, intercondylar distance, and condylar inclination on occlusal morphology have been discussed. Guidelines have been proposed for matching the type of articulator with the extent of treatment anticipated. The use of small, nonadjustable hinge articulators is not recommended.