酸蚀时间对乳牙釉质脱矿的影响

The effect of different etching time on enamel lesions of deciduous teeth

目的:采用激光共聚焦显微镜观察不同酸蚀时间对乳牙釉质脱矿的影响,对不同酸蚀时间形成的乳牙釉质的脱矿区进行形态学和数据学评价。方法:采用随机区组设计,将28颗离体下中切牙的唇面分别开4个窗,随机分到酸蚀30s(A)、60s(B)、90s(C)、120s(D)4个处理组中,采用32%磷酸凝胶对标本进行酸蚀处理。0.1mmol/L罗丹明B染色后,进行激光共聚焦显微镜扫描。采用SPSS11.0软件包对数据进行正态性检验和S-N-K法检验。结果:随着酸蚀时间的延长,釉质脱矿条带有所增粗,鱼鳞状结构变得不明显。衡量釉质脱矿程度的3个参数,荧光面积(FLA)、总荧光量(TF)和平均荧光量(AF)的均值随着酸蚀时间的延长而有所增大。A、B、C、D4组的FLA均值分别为(5.5±1.6)×102μm2、(7.4±2.7)×102μm2、(9.2±3.0)×102μm2和(9.6±2.9)×102μm2;4组的TF均值分别为(3.5±1.3)×104、(5.7±2.9)×104、(8.3±3.6)×104和(9.7±3.4)×104;AF均值分别为128.4±35.3、166.6±21.1、200.8±19.4和219.1±12.8。AF均值各组之间两两比较均有显著性差异,FLA、TF值在C组与D组之间无显著性差异。结论:随着酸蚀时间的延长,脱矿程度增大;不同的酸蚀时间形成脱矿类型不同。

PURPOSE：To study the effect of etching time on the demineralization of deciduous teeth enamel using confocal laser scanning microscope. METHODS：Twenty-eight primary incisors were used in this experiment. Each incisor was created 4 rectangular windows in the labial surface. The 4 windows of each tooth were randomly divided into 4 treatment groups with different etching time of 30s（A）,60s（B）,90s（C） and 120s（D）. All the treatment groups were applied with 32% phosphoric acid gel.After staining by 0.1mmol/L rhodamine B,the examination of the demineralization regions were performed by a confocal laser scanning microscope （CLSM）. The data was analyzed by test of normality and S-N-K analysis with SPSS 11.0 software package. RESULTS：As the etching time increased,the CLSM band was thickening,but the scales-liked structure was becoming unsharp.All the three parameters,area of the fluorescent lesion （FLA）,average lesion fluorescence（AF） and total lesion fluorescence（TF） were increasing. The FLA value of A,B,C,D were （5.5±1.6）× 10^2μm^2,（7.4±2.7）×10^2μm^2,（9.2±3.0）×10^2μm^2,（9.6±2.9）×10^2μm^2;The TF value of A,B,C,D were （3.5±1.3）×10^4,（5.7±2.9）× 10^4,（8.3±3.6）×10^4,（9.7±3.4）×10^4 ;The AF value of A,B,C,D were 128.4±35.3 ,166.6±21.1,200.8±19.4 and 219.1±12.8,respectively. The pairwise comparison of AF showed significant difference between the four groups,while there was no significant difference between group C（90s） and group D（120s） in both FLA and TF.CONCLUSIONS：The degree of demineralization increases with the etching time. Etching time has a large effect on the profile of demineralization.