【摘要】 本文报告四种不同条件刷牙方法的实验研究，初步证明楔状缺损是在牙龈萎缩、牙颈和牙根暴露的条件下长期横刷磨耗的结果；酸的作用仅能加快楔损的进程，并非楔损的直接病因。人工或机械横刷形成楔损的形态与临床所见有差异，其原因有待进一步研究。更多还原

【Abstract】 Four ways of brushing teeth were discussed in this article. The results showed that dental wedge-shaped defect was caused by the long period of cross brushing in the condition of gingival atrophy and exposure of dental neck and roots of teeth, while acrid was not direct cause,which only accelerate the process of defect. The appearance of wedge-shaped defect caused by artificial or mechanical effect was different from the clinical one,which needed further research.更多还原