Prevention of tooth hypersensitivity caused by the hydrodynamic action of zinc phosphate and composite resin luting cements (SEM) study.

This study was done to determine the role of cement liner as a reducing factor to the fluid movement in order to prevent tooth hypersensitivity according to the hydrodynamic theory during cementation of crowns. A total of fourty freshly extracted intact lower molar were selected for this study. After conventional tooth preparation the teeth were sub-divided into four equal groups to identify the role of cement liner in preventing the penetration of used cement into the dentinal tubules. Scanning electron microscopic study proved the efficiency of glass ionomer liner on preventing cement penetration into the dentinal tubules.