Effect of Galla chinensis on the remineralization of two bovine root lesions morphous in vitro

The present study aims to evaluate the effect of Galla chinensis compounds on the remineralization of two artificial root lesions morphous in vitro. Sixty bovine dentine blocks were divided into two groups and individually treated with two levels of demineralization solutions to form erosive and subsurface artificial carious lesions in vitro. Each group was then divided into three subgroups, each of which were treated with a remineralization solution （positive control）, deionized water （negative control）, or 4 000 mg-L-1 aqueous solutions of Galla chinensis extract. The dentine blocks were then subjected to a pH-cycling regime for 7 days. During the first 4 days, the daily cycle included 21-h deal and 3-h demineralization applications. The dentine blocks were dealt with the entire day during the remaining 3 days. Two specimens from each of the treatment groups were selected and observed under a polarized light microscope. Data collected using a laser scanning confocal microscope were computerized and analyzed. Galla chinensis extract clearly enhanced the remineralization of both erosive lesion and subsurface lesion patterns in the specimens （P〈0.05）. The level of remineralization of the erosive lesion by Galla chinensis extract was lower than that of the subsurface lesion （P〈0.05）. In addition, the remineralization of the subsurface lesion by Galla chinensis extract was higher than that of the remineralization solution （P〈0.05）. No significant difference between the remineralization of erosive lesions by Galla chinensis extract and the remineralization solution was observed （P〉0.05）. So Galla chinensis extract has the potential to improve the remineralization of artificial root lesions under dynamic pH-cyclic conditions, indicating its potential use as a natural remineralization medicine.