Clinical Studies of Dental Cements: III. Seven Zinc Oxide-Eugenol Cements Used for Temporarily Cementing Completed Restorations

Seven zinc oxide-eugenol cements with compressive strengths from 200 psi to 8,000 psi were used for temporarily cementing completed inlays, crowns, and bridges. The effectiveness of each cement in a variety of clinical situations is presented. Cement of 1,000 psi met the requirements of typical clinical cases most frequently. The cements of compressive strength 200, 400, 600, 2,200, and 3,500 psi were required in other clinical cases with sufficient frequency to justify their use. The cementation of dental restorations with zinc phosphate cement is often accom-panied by pain. It may be followed by hypersensitivity of the teeth and possible pulp death, which is caused by the irritant nature of the cement. These adverse effects of zinc phosphate cement are more decided in the extensive preparation that involves the cutting of many dentinal tubules than in the simple restoration. The effects are more noticeable in the teeth of young patients and in teeth free from previous caries or restorations. The increasing num-ber of fixed prostheses made in the last decade or so has indicated the nature of this clinical problem. Temporary cementa-tion with a sedative zinc oxide-eugenol mixture has become widely practiced to allow a period of time for reduction of the inflammation of the pulp before final cementation with zinc phosphate. This pro-cedure has been described by Ewing,1 Kazis and Kazis,2 McCracken,3 and Baraban.4 Two clinical problems are recognized in temporary cementation of restorations