Enamel Erosive Measured by a Profilometer and a Measuring Microscope

Objectives: The aim of this study was to measure the difference in the erosion depth of enamel measured by a profilometry (PM) and a measuring microscope (MM)

Methods: Sixty enamel specimens were divided into ten groups. Each specimen group were exposed to 50 ml of a carbonated drink with pH 2.38 or orange juice with pH 3.67 for 15, 30, 60, 120 and 180 minutes. Depths of eroded areas were measured with a profilometer and a measuring microscope. Data of average enamel loss was measured by MM and PM on all erosion times and were scatter plotted on a graph with regression fit. Correlations between the enamel loss measured by PM and MM were analyzed with a paired sample t-test to compare the discriminatory abilities of the two methods of analysis for all erosion times.

Results: Carbonated drink eroded enamel more than orange juice over the same exposure time. The regression fit in all study cases showed a high linear relationship (R2 =0.90) between measuring by PM and MM, but in cases where the erosion depth was lower than 1 ƒÝm, there were weak correlation coefficients (-0.007-0.303) for comparison between two the measurement methods.

Conclusions: MM is as least as good as PM for measuring depth of enamel loss. Although the precision of the two methods could not be implemented in less than 1ƒÝm depth measurement. The depth of focus (DOF) of the MM objective and the vertical magnification ability of the PM are important parameters to be measured accurately.