الفهرس 
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Abstract
Porcelain laminate veneers are conservative esthetic treatment of fractured, malaligned, worn or discolored teeth. Temporarization following PLVs preparation is sometimes important to protect the teeth against thermal insult, chemical irritation and provide esthetics. However residual temporary material may be left on the preparation surface and therefore interfere with final cementation.
The purpose of this study was to evaluate the shear bond strength of IPS Empress discs bonded to enamel and dentin following temporarization.
Fifty sound extracted human molars were used for this study, the proximal surfaces of teeth were ground flat to expose enamel (20 samples) and dentin (20 samples). Forty resin discs were constructed and cemented on the prepared teeth using either eugenol free cement or resin cement. Then the provisional discs were removed and traces of provisional cement were removed using either air abrasion or finishing stones.
The results of the study revealed that enamel recorded significantly higher shear bond strength than dentin. Using resin cement and removing the remnants of cement by air abrasion significantly increased the bond strength.
Within the limitations of this study the following conclusions can be drawn:
1- Temporizations of porcelain laminate veneers could affect the bond strength of the final veneers.
2- Removing the remnants of provisional cement by air abrasion significantly improved the shear bond strength of ceramic veneers.
3- Enamel provides a better substrate for bonding laminate veneers than dentin.