Distribution of major periodontopathic bacterial species and oral microbiome characteristics in children with type 1 diabetes across mixed and permanent dentitions

Periodontal pathogens are associated with diabetes, but few studies have examined type 1 diabetes, particularly in children. This study characterized oral bacteria in children with type 1 diabetes. The participants included 34 children with type 1 diabetes (23 in mixed dentition and 11 in permanent dentition) and 34 age- and biological sex-matched healthy children. By polymerase chain reaction targeting 10 major periodontopathic bacteria using dental plaque specimens, in the mixed dentition, detection rates of six periodontopathic bacteria were significantly higher in the diabetic children than in healthy children ( P < 0.05), whereas in the permanent dentition, a significant difference was observed for only one species ( P < 0.01). Microbiome analysis showed that α-diversity was significantly lower in the permanent dentition of diabetic children compared with healthy children ( P < 0.05). At the genus level, one genus differed significantly in the mixed dentition ( P < 0.05), whereas three genera differed in the permanent dentition ( P < 0.05). In summary, children with type 1 diabetes exhibit higher detection rates of periodontopathic bacterial species, primarily during the mixed dentition, and reduced microbiome diversity during the permanent dentition. These changes may contribute to oral dysbiosis and increase the risk of periodontal disease and type 1 diabetes.