Erciyes University, Department of Orthodontics, Kayseri, Turkey.
Angle Orthod. 2011 Mar;81(2):319-25. doi: 10.2319/062910-359.1.
To test the null hypothesis that there is no significant difference between the chitosan-containing and conventional nonfluoridated dentifrices in inhibition of enamel demineralization around orthodontic brackets.
Sixteen orthodontic patients who were scheduled to have extraction of four first premolars for orthodontic reasons were divided into two groups after the power of the study was estimated. Patients in the experimental group were instructed to use chitosan-containing dentifrice (AloeDent), and patients in the control group were instructed to use nonfluoridated dentifrice (Sensodyne Mint). After 60 days, the teeth were extracted and longitudinally sectioned. The demineralization was assessed by cross-sectional microhardness. The determinations were made at the bracket edge cementing limits and at occlusal and cervical points, 100 µm and 200 µm away from the edge. In all these positions, indentations were made at depths of 10, 20, 30, 50, 70, and 90 µm from the enamel surface. Analysis of variance (ANOVA) and Tukey test were used for statistical evaluation at P < .05 level.
ANOVA showed statistically significant differences for the factors of dentifrice type, position, and depth (P = .000). Statistically significant differences for microhardness values between two tested dentifrices were observed up to 20 µm of depth from the enamel surface (P < .05). Lower microhardness values were found for nonfluoridated dentifrice. Significant microhardness differences were also determined between materials at occlusal and cervical 0 µm positions (P < .05). At these positions, chitosan-containing dentifrice showed lower demineralization than the control.
Chitosan-containing dentifrice may reduce the enamel decalcification found in patients with poor oral hygiene. The null hypothesis is rejected.
检验壳聚糖含氟牙膏和传统非含氟牙膏在抑制正畸托槽周围釉质脱矿方面无显著差异的零假设。
根据研究能力估计，将 16 名因正畸原因需要拔除四颗第一前磨牙的正畸患者分为两组。实验组患者使用含壳聚糖的牙膏（AloeDent），对照组患者使用非含氟牙膏（Sensodyne Mint）。60 天后，拔出牙齿并进行纵向切片。通过横断面显微硬度评估脱矿情况。在托槽边缘粘接界限以及咬合和颈点处进行测定，距离边缘 100 µm 和 200 µm 处。在所有这些位置，在距釉质表面 10、20、30、50、70 和 90 µm 的深度处进行压痕。采用方差分析（ANOVA）和 Tukey 检验进行统计评估，P<0.05 水平。
ANOVA 显示牙膏类型、位置和深度因素存在统计学显著差异（P=0.000）。两种测试牙膏之间在距釉质表面 20 µm 深度内的显微硬度值存在统计学显著差异（P<0.05）。非含氟牙膏的显微硬度值较低。在咬合和颈 0 µm 位置也确定了材料之间的显著显微硬度差异（P<0.05）。在这些位置，含壳聚糖的牙膏比对照显示出更低的脱矿作用。
含壳聚糖的牙膏可能减少口腔卫生不良患者的釉质脱矿。零假设被拒绝。
