The reason for the differences, by our treatment, and similar with Tran Van Truong's work, 2011, is the fact that the dental caries examination criteria applied in Tran Thi My Hanh's research is according to guidelines of WHO, 1997, which treats dental caries happens when cavities are formed clinically, while that of us is based on International Caries Detection and Assessment System (ICDAS) supported by fluorescent laser. Thus, caries lesion, can be avoided optimally, especially incipient caries which is not mentioned in Tran Van Truong's and Tran Thi My Hanh's researches.