The purpose of this study is that of assessing in vitro the role of the salivary pellicle in the prevention of the dental erosion caused by the citric acid. Material and method: The salivary pellicle was obtained experimentally, in the laboratory. The enamel samples were prepared from intact human teeth, extracted for orthodontic or periodontal purposes. These were incorporated in epoxy resin bases and were treated with 0.1% and 1% citric acid for 1.5, respectively 10 minutes. Half of the samples were stored in saliva for 24 hours and constituted the study group, whereas the other half, which was not covered by the pellicle, represented the control group. The calcium quantities released in the solution were measured by using atomic absorption spectrometry.
Results: The salivary pellicle inhibited the calcium release in all the analyzed subgroups, in comparison with the control group (the exception was the ten minutes exposure to a 1% concentration of the acid). Significant losses were registered for the specimens that were not covered by the salivary film, at approximately 1 minute from the exposure to 0.1% citric acid. These losses registered a growth with the increase of the exposure duration and of the acid concentration.
Conclusions: The results of the study confirm the fact that salivary pellicle protect, for the short term, the enamel surfaces from the erosion caused by organic acids.