A method to measure clinical erosion: the effect of orange juice consumption on erosion of enamel

Objective: Acidic soft drinks are frequently implicated in dental erosion, but there are limited supporting data. Research is problematic due to the insidious nature of erosion and accuracy in assessing tissue loss. The aim of this study was to develop and validate, using a negative control, a model to accurately measure erosion in situ due to a single aetiological agent over a relatively short time period. Methods: An intra-oral appliance capable of retaining an enamel sample was designed in order to assess the effect of orange juice consumption on enamel. The study was a single centre, randomized, placebo controlled, blind, crossover design. Results: Ten subjects, each consuming 11 of orange juice per day for 15 days, showed significantly more erosion on the enamel specimens than the same subjects consuming 11 of water per day over the same lime period, measurements undertaken with surfometry. The same investigation was performed in vitro. Again, orange juice was significantly more erosive; indeed, it was in the order of 10 times that produced in situ. Surface microhardness testing in situ and in vitro demonstrated statistically significant differences between exposed and unexposed areas after orange juice treatment. Conclusions: Changes produced by water either in situ or in vitro were always well within the baseline measurement parameters (+/-0.3 mu m) set down for the method and hence validated the clinical model in terms of reproducibility and accuracy in measurement. It is concluded that this method has confirmed the erosive potential of orange juice in situ. The method could have many applications to study dental erosion under highly controlled conditions and over realistic time periods. (C) 1998 Elsevier Science Ltd. All rights reserved.