Chronic periodontitis is an inflammatory disease of the tooth-supporting tissues that develops gradually and is caused by the immune response to microbial infection in the oral cavity. One of its main etiological factors is subgingival bacterial plaque, a complex community of microorganisms that accumulate below the gingival margin. This plaque triggers an inflammatory response that leads to progressive destruction of periodontal tissues.
Composition and Role of Subgingival Plaque
Subgingival plaque consists of various types of bacteria, including gram-negative anaerobes such as Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola, collectively known as the “red complex.” These microorganisms produce enzymes and endotoxins that stimulate the release of inflammatory mediators and play a role in periodontal tissue destruction. In addition to the direct activity of bacteria, another critical factor is the host immune response to the biofilm. The body produces antimicrobial peptides such as beta defensins, which protect the epithelium from microbial invasion. However, in chronic conditions, this balance is disrupted.
Recent Research
In an article published in Jurnal MKGK FKG UGM written by Sugiharto Wijaya and Sri Lelyati C Masulili, it is noted that:
“Beta defensins, as antimicrobial polypeptides, function as components of the innate immune system to protect tissues from microbial invasion.” However, in patients with chronic periodontitis, the expression of beta defensins may decrease or be insufficient to inhibit the colonization of pathogenic subgingival bacteria. This exacerbates inflammation and accelerates the progression of periodontal disease.
Role of Immunity and Disease Progression
An imbalance between bacterial load/virulence and host defense capacity triggers the release of inflammatory mediators such as interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α). These mediators stimulate osteoclast activity, leading to alveolar bone resorptionand worsening of periodontal conditions.
Subgingival plaque also disrupts the barrier function of the gingival epithelium, allowing microorganisms to penetrate deeper tissues and stimulate long-term chronic inflammation.
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Subgingival bacterial plaque is a key factor in the pathogenesis of chronic periodontitis. The host immune response to bacterial biofilms, including beta defensin production, plays a central role in determining disease progression. Based on the referenced article:
Further research and understanding of microbial interactions with the local immune system are essential to developing more effective therapies to prevent and manage chronic periodontitis.
References
MKGK, Sugiharto Wijaya dan Sri Lelyati C Masulili, Beta defensin polypeptides in relation to chronic and aggressive periodontitis, https://jurnal.ugm.ac.id/mkgk/article/view/32006
Author: Rizky B. Hendrawan | Editor: drg. Aulia Ayub, Sp.Ort
Photo: Freepik
