Matos A B, Palma R G, Saraceni C H, Matson E
Departamento de Dentística, Faculdade de Odontologia, Universidade de São Paulo, Brasil.
Braz Dent J. 1997;8(1):35-41.
The aim of this in vitro study was to evaluate, using scanning electron microscopy (SEM), the effects of acid solutions on dentin surface, and to analyze the depth of demineralization that the acid solutions cause on dentin, using different acids. Fifteen 3-mm thick dentin discs were prepared from the middle third of human molars. Standard smear layer was prepared on the dentin surface using 600 grit sandpaper, for 1 minute. The acids used were 10%, 35% and 37.5% phosphoric acid and 10% maleic acid, for 15 seconds, washed and dried. The control group received no treatment. Dentin discs were fractured, observed on the horizontal surface and also on the fractured surface to evaluate the depth of demineralization. Specimens were immersed in 4% glutaraldehyde in phosphonate buffer, and prepared for SEM examination at 2000X and 4000X magnification. Acid etching of dentin, regardless of the concentration of phosphoric acid, caused removal of the smear layer, exposing the apertures of dentinal tubules. This was not observed when 10% maleic acid was used. At the fractured surface, one could observe an increase in demineralization of the width of dentinal tubules, to a specific depth of about 8.19 to 11 mm, except for 10% maleic acid.
本体外研究的目的是使用扫描电子显微镜（SEM）评估酸性溶液对牙本质表面的影响，并分析不同酸性溶液对牙本质造成的脱矿深度。从人类磨牙的中三分之一处制备了15个3毫米厚的牙本质圆盘。使用600目砂纸在牙本质表面制备标准玷污层1分钟。使用的酸为10%、35%和37.5%的磷酸以及10%的马来酸，处理15秒后冲洗并干燥。对照组未接受处理。将牙本质圆盘折断，在水平表面和折断表面观察以评估脱矿深度。将标本浸入膦酸盐缓冲液中的4%戊二醛中，并制备用于2000倍和4000倍放大倍数的SEM检查。无论磷酸浓度如何，牙本质的酸蚀都会导致玷污层去除，使牙本质小管的开口暴露。使用10%马来酸时未观察到这种情况。在折断表面，可以观察到除10%马来酸外，牙本质小管宽度的脱矿增加至约8.19至11毫米的特定深度。
