A comparison of the erosive susceptibility of cuspal and cervical enamel using an ultrasonic technique

The aim of this study was to compare the erosive susceptibility of cuspal and cervical enamel from human premolar and molar teeth. Small blocks of cervical and cuspal enamel were immersed in either orange juice or Coca-Cola at 37 degrees C and the surface enamel loss was measured by surfometry at 1, 2, 3 and 4 h. Additionally, once-hourly enamel loss was measured, specimens were placed in an ultrasonic bath containing water and ultrasonicated for 5 s to determine the degree of surface demineralization. A further set of enamel specimens were prepared that had 100 microm of the enamel surface removed. This was done to remove the hypermineralized surface enamel layer. Surface enamel loss in orange juice at 4 h, following ultrasonication, ranged from 13.2 to 16.9 microm. The surface enamel loss in Coca-Cola at 4 h, following ultrasonication, ranged from 21.7 to 27.5 microm. Subsurface enamel loss in orange juice at 4 h, following ultrasonication, ranged from 10.7 to 16.1 microm. The subsurface enamel loss in Coca-Cola for 4 h, following ultrasonication, ranged from 36.8 to 37.2 microm. Overall, little difference was found in the erosive susceptibility of cervical and cuspal enamel to the effects of orange juice or Coca-Cola.