Trung, N. T., Loan, H. K., Duy, H. B. and Hạnh, K. T. H. (2021) “Prevalence of gingivitis and sensitivity, specificity of dental imaging with smartphone in diagnosis gingivitis among 15 - year - old students in Hung Yen ”, Journal of Medical Research, 143(7), pp. 86-93. doi: 10.52852/tcncyh.v143i7.652.