Viral Infections and Cancer Research

Comparative Microbiological Analysis of Microflora in Root Carious Lesions Across Different Age Groups: Exploring Bacterial Diversity, Biofilm Formation and Antibiotic Resistance

Tasnim Shamrin

Tasnim Shamrin, City Dental College & General Hospital, Dhaka, Bangladesh

Koushik Saha Kabyo

Koushik Saha Kabyo, City Dental College & General Hospital, Dhaka, Bangladesh

Summaia Mahjabein Sarah

Summaia Mahjabein Sarah, City Dental College & General Hospital, Dhaka, Bangladesh

Babujan Ansari

Babujan Ansari, City Dental College & General Hospital, Dhaka, Bangladesh

Rayhan Chowdhury

Rayhan Chowdhury, Bangladesh University of Health Sciences (BUHS), Bangladesh

Md. Ashiqur Rahman

Md. Ashiqur Rahman, Novus Clinical Research Services Limited, Dhaka, Bangladesh

Keywords: actinomyces spp.; aerobic/anaerobic bacteria; lactobacillus; root caries; streptococcus mutans

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Abstract

 Background: Root caries, increasingly prevalent in aging populations, poses a significant challenge for oral health. Gingival recession exposes tooth roots, leading to vulnerability to microbial colonization. However, the microbial factors influencing the progression of root caries in Bangladesh have not been extensively studied.

Aim: The aim of this study was to evaluate the prevalence of Streptococcus mutans, Lactobacillus, and Actinomyces species in root carious lesions in middle-aged and older adults in the Bangladeshi population and to comparatively assess the microbial count between the two age groups.

Materials and Methods: A total of 180 adult patients aged 35-75 years were included in the study, with 90 individuals in the middle-aged group (35-44 years) and 90 in the older group (55-75 years). Specimens from root carious lesions were collected for bacteriological analysis using standard culture techniques. Isolation and identification of Streptococcus mutans, Lactobacillus, and Actinomyces species were performed on selective media.

Results: The microbial analysis was performed using the Chi-square test with SPSS 25. Streptococcus mutans was identified in 56.7% of samples, Lactobacillus in 28.3%, and Actinomyces species in 15%. These microorganisms were predominantly found in the older age group, with a significant association between the age group and the presence of Lactobacillus (P=0.024).

Conclusions: This study found that both aerobic Gram-positive cocci (Streptococcus mutans, Lactobacillus) and anaerobic bacteria (Actinomyces spp.) were more prevalent in root carious lesions in older adults compared to middle-aged individuals in Bangladesh. The findings underscore the age-related microbial shifts in root caries and suggest the need for targeted prevention and treatment strategies for the aging population.

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References

1.Karki AJ, Monaghan N, Morgan M. Oral health status of older people living in care homes in Wales. British dental journal. 2015 Oct 9;219(7):331-4.

2.Patel J, Wallace J, Doshi M, Gadanya M, Yahya IB, Roseman J, Srisilapanan P. Oral health for healthy ageing. The Lancet Healthy Longevity. 2021 Aug 1;2(8):e521-7.

3.Darout IA. Oral bacterial interactions in periodontal health and disease. J Dent Oral Hyg. 2014;6(5):51-7.

4.Shamrin T, Khatun MA, Babu MR, Akter T, Islam S, Rahman MA. Comparative analysis of antibiotic sensitivity pattern in Streptococcus mutans isolated from dental caries of different age & sex group in Dhaka city, Bangladesh. World Journal of Biology Pharmacy and Health Sciences. 2024;20(1).

5.Dubey S, Dubey S, Gupta A, Sharma V. Biofilm-Mediated dental diseases. Biofilms in Human Diseases: Treatment and Control. 2019:91-116.

6.Gross EL, Beall CJ, Kutsch SR, Firestone ND, Leys EJ, Griffen AL. Beyond Streptococcus mutans: dental caries onset linked to multiple species by 16S rRNA community analysis.

7.Takahashi N, Nyvad B. Ecological hypothesis of dentin and root caries. Caries research. 2016 Jul 27;50(4):422-31.

8.Eşian D, Man AD, Burlibasa L, Burlibasa M, Perieanu MV, Bică CI. Salivary level of streptococcus mutans and lactobacillus spp. related to a high a risk of caries disease. Rom Biotechnol Lett. 2017;22(2):12496-503.

9.9. Aparna A, Hegde MN, Shetty V. Evaluation of microflora of root carious lesions in different age groups: A microbiological study. European Journal of General Dentistry. 2013 May;2(02):130-3.

10.Dioguardi M, Quarta C, Alovisi M, Crincoli V, Aiuto R, Crippa R, Angiero F, Laneve E, Sovereto D, De Lillo A, Troiano G. Microbial association with genus actinomyces in primary and secondary endodontic lesions, review. Antibiotics. 2020 Jul 22;9(8):433.

11.Banas JA, Zhu M, Dawson DV, Blanchette DR, Drake DR, Gu H, Frost R, McCaulley G, Levy SM. Acidogenicity and acid tolerance of Streptococcus oralis and Streptococcus mitis isolated from plaque of healthy and incipient caries teeth. Journal of Oral Microbiology. 2016 Jan 1;8(1):32940.

12.Hegde MN, Jyothi M. Prevalence of root surface caries among population of South Canara District of Karnataka‑ An Epidemiological Study JIDA 2011;5:616‑8.

13.Conrads G. About I. Pathophysiology of dental caries. Monogr Oral Sci. 2018 May 24;27:1-0.

14.Hashimoto K, Sato T, Shimauchi H, Takahashi N. Profiling of dental plaque microflora on root caries lesions and the protein-denaturing activity of these bacteria. American Journal of Dentistry. 2011 Oct 1;24(5):295.

15.Shen S, Samaranayake LP, Yip HK, Dyson JE. Bacterial and yeast flora of root surface caries in elderly ethnic Chinese. Oral Dis 2002;8:207‑17.

16.Ellen RP, Banting DW, Fillery ED. Longitudinal Microbiological Investigation of a Hospitalized Population of Older Adults with a High Root Surface Caries Risk. J Dent Res 1985b; 64:1377‑81.

17.AlEraky DM, Madi M, El Tantawi M, AlHumaid J, Fita S, AbdulAzeez S, Borgio JF, Al-Harbi FA, Alagl AS. Predominance of non-Streptococcus mutans bacteria in dental biofilm and its relation to caries progression. Saudi journal of biological sciences. 2021 Dec 1;28(12):7390-5..