<p>Objective　Continuous oral health care and regular dental visits are important for maintaining oral health. As a result of the high communicability of the coronavirus disease (COVID-19), individuals are reluctant to visit medical institutions. It is as yet unclear how the oral health of the population has been affected by the interruption of regular medical services during the COVID-19 pandemic. This study aimed to examine the association between the status of regular dental visits and changes in oral health among high school students during the pandemic using data from routine medical checkups conducted at a school, as well as data obtained from a questionnaire-based survey conducted simultaneously with medical checkups.</p><p>Methods　This study included 878 participants (comprising freshmen and sophomores) during the 2019 academic year from a high school in Fukuoka prefecture, Japan. Data on the frequency of dental checkups and anxiety related to dental visits during the pandemic was obtained through a questionnaire-based survey. Changes in dental health and gingival status between 2019 and 2020 were determined using data from routine medical checkups at the school. Poisson regression analysis with robust standard errors was used to evaluate the association between changes in dental health and gingival status and the status of regular dental visits.</p><p>Results　Of 878 participants, 417 (47.5%) did not have regular dental visits, 320 (36.4%) continued to have regular dental visits, and 141 (16.1%) had interrupted regular dental visits during the pandemic. In the interrupted regular dental visit group, 30.5% of participants were anxious about visiting a dental institution, which was a significantly higher proportion than other groups. Of the 521 participants who did not have gingival inflammation at the time of dental checkup in 2019, gingival inflammation at the time of dental checkup in 2020 was observed in 31.0% of participants having no regular dental visits, 20.2% participants having regular dental visits, and 38.2% participants having interrupted regular dental visits. The multivariable adjusted incidence rate ratios were 1.95 [95% confidence interval (CI), 1.34-2.84] in the interrupted regular dental visit group and 1.50 (95%CI,1.07-2.10) in the no regular dental visit group. There was no significant association between interruption of regular dental visits and changes in dental health status.</p><p>Conclusion　The study results showed that there was a significant association between interruptions in regular dental visits and anxiety related to dental visits during the COVID-19 pandemic, and that a higher proportion of participants who had interruptions in regular dental visits had gingival inflammation at the time of the medical checkup at the school.</p>