Dental healthcare is very important since dental and oral hygiene should be maintained. Statistics showed that more than 80% of children in developed and developing countries suffer from dental disease. This study aimed to see the safety of OHIS (Oral Hygiene Index Simplified) in primary school students who got and did not get little dentist cadre training in Bangli Regency in 2019. The study was done in an experimental design: pre and post-test with control design, which was conducted in August-September 2019. The sample in this study is 366 students. The difference in OHIS scores before and after treatment in the control group and treatment group was carried out by the bivariate Mann Whitney U Test. The results of the study showed that before dental health training was conducted, there were 54.3% of primary school students in the treatment group with good OHIS score criteria, and after the training was carried out as many as 98.4% of the students in the treatment group had a good OHIS. Additionally, prior to the training, 57.5% of the control group had fair OHIS criteria score. Then, after the training was carried out, 73.7% of the control group had good OHIS score. Hence, the study concluded that there was a significant difference in the OHIS of primary school students who got little doctor training prior to and after the training. Also, there was a significant difference in the OHIS of the students who did not get such treatment before and after the training.