Diversity of site-specific microbes of occlusal and proximal lesions in severe- early childhood caries (S-ECC)

Kausar Sadia Fakhruddin; Lakshman Perera Samaranayake; Rifat Akram Hamoudi; Hien Chi Ngo; Hiroshi Egusa

doi:10.1080/20002297.2022.2037832

Diversity of site-specific microbes of occlusal and proximal lesions in severe- early childhood caries (S-ECC)

J Oral Microbiol. 2022 Feb 13;14(1):2037832. doi: 10.1080/20002297.2022.2037832. eCollection 2022.

Authors

Kausar Sadia Fakhruddin^{1

2}, Lakshman Perera Samaranayake³, Rifat Akram Hamoudi^{4

5}, Hien Chi Ngo⁶, Hiroshi Egusa²

Affiliations

¹ Department of Preventive and Restorative Dentistry, University of Sharjah, Sharjah, UAE.
² Division of Molecular and Regenerative Prosthodontics, Tohoku University Graduate School of Dentistry, Sendai-city, Japan.
³ The University of Hong Kong, Hong Kong Special Administrative Region, China.
⁴ Sharjah Institute for Medical Research, College of Medicine, University of Sharjah, Sharjah, UAE.
⁵ Division of Surgery and Interventional Science, University College London, London, UK.
⁶ Uwa Dental School, The University of Western Australia, Perth, Australia.

Abstract

Background: Severe-early childhood caries (S-ECC) a global problem of significant concern, commonly manifest on the occlusal, and proximal surfaces of affected teeth. Despite the major ecological differences between these two niches the compositional differences, if any, in the microbiota of such lesions is unknown.

Methods: Deep-dentine caries samples from asymptomatic primary molars of children with S-ECC (n 19) belonging to caries-code 5/6, (ICDAS classification) were evaluated. Employing two primer pools, we amplified and compared the bacterial 16S rRNA gene sequences of the seven hypervariable regions (V2-V4 and V6-V9) using NGS-based assay.

Results: Bray-Curtisevaluation indicated that occlusal lesions (OL) had a more homogeneous community than the proximal lesions (PL) with significant compositional differences at the species level (p = 0.01; R- 0.513). Together, the occlusal and proximal niches harbored 263 species, of which 202 (76.8%) species were common to both , while 49 (18.6%) and 12 (4.6%) disparate species were exclusively isolated from the proximal and occlusal niches, respectively. The most commonl genera at both niches included Streptococcus, Prevotella, and Lactobacillus. S. mutans was predominant in PL (p ≤ 0.05), and Atopobium parvulum (p = 0.01) was predominant in OL.

Conclusions: Distinct differences exist between the caries microbiota of occlusal and proximal caries in S-ECC.

Keywords: Severe-early childhood caries (S-ECC); dentine caries; microbial diversity; occlusal-caries lesion; proximal-caries lesion.

Grants and funding

This work was funded by the University of Sharjah oral biofilm in health and disease group establishment fund.