Comparative Analysis of Oral Bacterial Load and Antibiotic Susceptibility Profiles in Libyan Type 2 Diabetes Mellitus (T2DM) and Periodontitis Cohorts
DOI:
https://doi.org/10.54361/LJMR.20.3.98Keywords:
Oral microbiology, Bacterial load, Colony forming units, Antibiotic hypersensitivity, Type 2 diabetes mellitus, PeriodontitisAbstract
Background: Type 2 diabetes mellitus (T2DM) and periodontitis are prevalent inflammatory conditions interacting bidirectionally. Although genomic alterations have been documented, it remains unclear how early-onset T2DM and periodontitis modify culturable bacterial load and antibiotic hypersensitivity patterns in plaque biofilms in the Libyan population. Methods: We conducted a cross-sectional culturing study using supragingival and subgingival plaque from 60 adults (30–40 years) in Benghazi, divided into healthy (H, n=10), periodontitis (P, n=10), T2DM (n=20), and T2DM with periodontitis (T2DM_P, n=20). Total culturable aerobic and anaerobic bacterial loads were determined via colony-forming units (CFU/mg). Antibiotic hypersensitivity profiling was evaluated using the Kirby-Bauer disk diffusion method against amoxicillin, metronidazole, clindamycin, and doxycycline. Results: The T2DM_P group exhibited the highest total anaerobic bacterial load (7.84 ± 0.42 log10 CFU/mg) compared to the healthy group (4.12 ± 0.28 log10 CFU/mg; p < 0.001). Antibiotic hypersensitivity testing revealed significantly reduced zones of inhibition (increased resistance) to metronidazole and amoxicillin in plaque isolates from the T2DM_P and P groups compared to healthy individuals (p < 0.01). Clindamycin and doxycycline retained the highest overall hypersensitivity zones across all cohorts. Conclusion: Early-onset T2DM combined with periodontitis significantly intensifies the total pathogenic bacterial load and reduces antibiotic susceptibility profiles within dental plaque. Culturable monitoring provides a pragmatic window for targeted local medical-dental interventions.
Downloads
References
1. Zhao M, Xie Y, Gao W, Li C, Ye Q, Li Y. Diabetes mellitus promotes susceptibility to periodontitis—novel insight into the molecular mechanisms. Front Endocrinol (Lausanne). 2023;14:1192625. doi:10.3389/fendo.2023.1192625
2. Xiang D, Sun Y, Jiao C, Guo Y, Fei Y, Ren B, et al. Diabetes and periodontitis: the role of a high-glucose microenvironment in periodontal tissue cells and corresponding therapeutic strategies. Stem Cell Res Ther. 2025;16(1):366. doi:10.1186/s13287-025-04221-6
3. Butera A, Pascadopoli M, Gallo S, Alovisi M, Lovati E, Mutti E, et al. Domiciliary management of periodontal indexes and glycosylated hemoglobin (HbA1c) in type 1 diabetic patients with paraprobiotic-based toothpaste and mousse: randomized clinical trial. Appl Sci. 2022;12(17):8610. doi:10.3390/app12178610
4. Vieira Lima CP, Grisi DC, Guimarães MDCM, Salles LP, Kruly PDC, Do T, et al. Enrichment of sulphate-reducers and depletion of butyrate-producers may be hyperglycaemia signatures in the diabetic oral microbiome. J Oral Microbiol. 2022;14(1):2082727. doi:10.1080/20002297.2022.2082727
5. Bao K, Afacan B, Grossmann J, Silbereisen A, Öztürk V, Emingil G, et al. Saliva versus all-site microbiome and proteome mapping in periodontitis. J Clin Periodontol. 2025;52(12):1540-9. doi:10.1111/jcpe.13540
6. Chattopadhyay S, Malayil L, Chopyk J, Smyth E, Kulkarni P, Raspanti G, et al. Oral microbiome dysbiosis among cigarette smokers and smokeless tobacco users compared to non-users. Sci Rep. 2024;14(1):10394. doi:10.1034/s1234-9876.14103
7. Kilian M, Chapple ILC, Hannig M, Marsh PD, Meuric V, Pedersen AML, et al. The oral microbiome—an update for oral healthcare professionals. Br Dent J. 2016;221(10):657-66. doi:10.1031/bdj.2016.657
8. Omori M, Kato-Kogoe N, Sakaguchi S, Kamiya K, Fukui N, Gu YH, et al. Characterization of salivary microbiota in elderly patients with type 2 diabetes mellitus: a matched case–control study. Clin Oral Investig. 2022;26(7):493-504. doi:10.1007/s00784-021-04212-3
9. Chapple ILC, Mealey BL, Van Dyke TE, Bartold PM, Dommisch H, Eickholz P, et al. Periodontal health and gingival diseases and conditions on an intact and a reduced periodontium: consensus report of workgroup 1 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions. J Periodontol. 2018;89(Suppl 1):S74-84. doi:10.1002/JPER.17-0719
10. Miao X, Cao H, Chen J, Gao Y, Li J, Zhang B, et al. Supragingival microbial profiles in caries-free and caries-active adolescents treated with fixed orthodontics. Curr Res Microb Sci. 2025;9:100455. doi:10.1016/j.crmicr.2025.100455
11. Lee R, Park J, Park Y, Kim K, Ha J, Lee J. Microbial profiling of saliva, oral rinse, subgingival plaque and GCF reveals site-specific dysbiosis in periodontitis: a within-subject comparison of 150 participants. J Clin Periodontol. 2025;52(1):22-31. doi:10.1111/jcpe.13991
12. Matsha TE, Prince Y, Davids S, Chikte U, Erasmus RT, Kengne AP, et al. Oral microbiome signatures in diabetes mellitus and periodontal disease. J Dent Res. 2020;99(6):658-65. doi:10.1177/0022034520913261
13. Lamont RJ, Koo H, Hajishengallis G. The oral microbiota: dynamic communities and host interactions. Nat Rev Microbiol. 2018;16(12):745-59. doi:10.1038/s41579-018-0089-x
14. Ganesan SM, Joshi V, Fellows M, Dabdoub SM, Nagaraja HN, O'Donnell B, et al. A tale of two risks: smoking, diabetes and the subgingival microbiome. ISME J. 2017;11(9):2075-89. doi:10.1038/ismej.2017.72
Downloads
Published
Issue
Section
License
Copyright (c) 2026 Libyan Journal of Medical Research

This work is licensed under a Creative Commons Attribution 4.0 International License.
Open Access Policy
Libyan journal of medical Research (LJMR).is an open journal, therefore there are no fees required for downloading any publication from the journal website by authors, readers, and institution.
The journal applies the license of CC BY (a Creative Commons Attribution 4.0 International license). This license allows authors to keep ownership f the copyright of their papers. But this license permits any user to download , print out, extract, reuse, archive, and distribute the article, so long as appropriate credit is given to the authors and the source of the work.
The license ensures that the article will be available as widely as possible and that the article can be included in any scientific archive.
Editorial Policy
The publication of an article in a peer reviewed journal is an essential model for Libyan journal of medical Research (LJMR). It is necessary to agree upon standards of expected ethical behavior for all parties involved in the act of publishing: the author, the journal editorial, the peer reviewer and the publisher.
Any manuscript or substantial parts of it, submitted to the journal must not be under consideration by any other journal. In general, the manuscript should not have already been published in any journal or other citable form, although it may have been deposited on a preprint server. Authors are required to ensure that no material submitted as part of a manuscript infringes existing copyrights, or the rights of a third party.
Authorship Policy
The manuscript authorship should be limited to those who have made a significant contribution and intellectual input to the research submitted to the journal, including design, performance, interpretation of the reported study, and writing the manuscript. All those who have made significant contributions should be listed as co-authors.
Others who have participated in certain substantive aspects of the manuscript but without intellectual input should only be recognized in the acknowledgements section of the manuscript. Also, one of the authors should be selected as the corresponding author to communicate with the journal and approve the final version of the manuscript for publication in the LJMR.
Peer-review Policy
- All the manuscripts submitted to LJMR will be subjected to the double-blinded peer-review process;
- The manuscript will be reviewed by two suitable experts in the respective subject area.
- Reports of all the reviewers will be considered while deciding on acceptance/revision or rejection of a manuscript.
- Editor-In-Chief will make the final decision, based on the reviewer’s comments.
- Editor-In-Chief can ask one or more advisory board members for their suggestions upon a manuscript, before making the final decision.
- Associate editor and review editors provide administrative support to maintain the integrity of the peer-review process.
- In case, authors challenge the editor’s negative decision with suitable arguments, the manuscript can be sent to one more reviewer and the final decision will be made based upon his recommendations.











https://portal.issn.org/resource/ISSN/2413-6069