Objective  To describe the prevalence of dental caries among primary and high school students in Hedong district of Linyi city and to provide evidences for developing oral health interventions in the students.

  Methods  We collected the data on dental caries examination of 124 690 primary and high school students in Hedong district of Linyi city between 2014 and 2016 and prevalence rate of dental caries among the students was calculated based relevant standards.

  Results  Among all the students examined, 46 060 were diagnosed with dental caries and the overall detection rate of dental caries was 36.94%, with the dental caries detection rate of 6.20% for permanent teeth and 31.93% for deciduous teeth; the overall detection rate of dental caries was significantly higher among girl students than among boy students (39.52% vs. 34.79%, P < 0.01) and the overall rate was significantly higher among primary students than among junior high school students (42.88% vs. 17.68%, P < 0.01). During the period among all the students, the yearly overall dental caries detection rate was 35.94%, 37.35%, and 39.51%, with a significant increasing trend (P < 0.01) and the yearly dental caries detection rate for permanent teeth was 5.33%, 6.53%, and 8.64%, also with a significant increasing trend (P < 0.01). For all the students with dental caries, the decay missing filling tooth rate for permanent teeth caries was 6.64% and significantly higher than that (2.21%) for deciduous teeth caries (P < 0.01).

  Conclusion  The detection rate of dental caries increased among primary and high school students in Hedong district of Linyi city between 2104 and 2016; the dental caries detection rate was higher among girls students than among boy students and higher among junior high school students than among primary school students.