The association of Fcgamma receptor IIIb genetic polymorphism and susceptibility to periodontitis in Taiwanese individuals

Association of vitamin D receptor gene polymorphisms and periodontitis in a Taiwanese Han population

Background/purpose

: Genetic polymorphisms in the vitamin D receptor (VDR) gene are related to the immune response and bone metabolism, both of which are implicated in the pathogenesis of periodontitis. This study was to investigate the association between VDR-gene polymorphisms and periodontitis among a Taiwanese Han ethnic population.

Materials and methods

Ninety-two aggressive periodontitis (AgP), 385 chronic periodontitis (CP) and 163 healthy controls (HC) were recruited from dental clinics. Demographic characteristics and possible confounding factors were obtained using a self-reported questionnaire. The VDR rs731236 (TaqI), rs7975232 (ApaI), rs1544410 (BsmI), and rs2228570 (FokI) polymorphisms were genotyped using PCR-RFLP methods. Statistical analyses were applied to determine the associations.

Results

The individual VDR polymorphisms were not associated with risk of AgP and CP. The f allele of rs2228570 was related to decreased risk for AgP. Subjects with TAbF (adjusted OR = 7.2, 95% CI = 3.2–7.2, p < 0.0001) or TAbf (adjusted OR = 0.17, 95% CI = 0.05–0.48, p = 0.002) combined polymorphisms were significantly associated with AgP. Subjects with Tabf (adjusted OR = 2.6, 95% CI = 1.8–3.8, p < 0.0001), TAbF (adjusted OR = 4.4, 95% CI = 2.6–8.1, p < 0.0001), TabF (adjusted OR = 0.36, 95% CI = 0.2–0.5, p < 0.0001), or TAbf (adjusted OR = 0.45, 95% CI = 0.3–0.7, p = 0.001) combined polymorphisms were significantly associated with CP.

Conclusion

The study indicates that VDR gene polymorphisms are associated with AgP and CP in a Taiwanese Han population.

Neutrophils in periodontal inflammation

Neutrophils (also called polymorphonuclear leukocytes) are the most abundant leukocytes whose primary purpose as anti-microbial professional phagocytes is to kill extracellular pathogens. Neutrophils and macrophages are phagocytic cell types that along with other cells effectively link the innate and adaptive arms of the immune response, and help promote inflammatory resolution and tissue healing. Found extensively within the gingival crevice and epithelium, neutrophils are considered the key protective cell type in the periodontal tissues. Histopathology of periodontal lesions indicates that neutrophils form a 'wall' between the junctional epithelium and the pathogen-rich dental plaque which functions as a robust anti-microbial secretory structure and as a unified phagocytic apparatus. However, neutrophil protection is not without cost and is always considered a two-edged sword in that overactivity of neutrophils can cause tissue damage and prolong the extent and severity of inflammatory periodontal diseases. This review will cover the innate and inflammatory functions of neutrophils, and describe the importance and utility of neutrophils to the host response and the integrity of the periodontium in health and disease.