Microbiology of molar–incisor hypomineralization lesions. A pilot study

Abstract

<b>Objective</b>: An insufficient mineralization (hypomineralization) in the teeth during the maturation stage of amelogenesis cause defects in 3-44% of children. Here, we describe for the first time the microbiota associated with these defects and compared it to healthy teeth within the same subjects. <b>Methods</b>: Supragingival dental plaque was sampled from healthy and affected teeth from 25 children with molar-incisor hypomineralization (MIH). Total DNA was extracted and the 16S rRNA gene was sequenced by Illumina sequencing in order to describe the bacterial composition. <b>Results</b>: We detected a higher bacterial diversity in MIH samples, suggesting better bacterial adhesion or higher number of niches in those surfaces. We found the genera <i>Catonella, Fusobacterium, Campylobacter, Tannerella, Centipeda, Streptobacillus, Alloprevotella</i> and <i>Selenomonas</i> associated with hypomineralized teeth, whereas <i>Rothia</i> and <i>Lautropia</i> were associated with healthy sites. <b>Conclusion</b>: The higher protein content of MIH-affected teeth could favour colonization by proteolytic microorganisms. The over-representation of bacteria associated with endodontic infections and periodontal pathologies suggests that, in addition to promote caries development, MIH could increase the risk of other oral diseases.