Viability of Anaerobic Bacteria in Dental Sub-Gingival Calculus and Its Minerlization – An Observational Microbiological Study

Abstract

Background: Dental calculus, a mineralized product of plaque, remains ignored and is considered as a fossilized remnant of minor significance. Dental plaque is still considered as the main culprit in etiopathogenesis of periodontal disease. Several studies suggest that calculus has a porous and spongy nature because of which it may act as a reservoir for endotoxins and bacterial antibodies. However, the viability of bacteria in sub gingival calculus and its role in the pathogenesis and disease progression still remains a mystery. The present study aims to investigate the viability of bacteria within sub-gingival calculus and to assess the degree of mineralization of dental calculus and the variation of viable micro flora corresponding to the extent of mineralization. Materials and Methods: Eighteen samples of sub gingival calculus were harvested from patients with chronic inflammatory periodontal disease. The samples were divided into two groups, Group 1 (non-irradiated) and Group 2 (samples exposed to UV radiation) and Group 3 (samples assessed for mineralization). Group 1 and 2 samples were utilized for anaerobic culture to detect the presence of anaerobic bacteria. Group 3 samples were crushed in a Universal testing machine and mineralization was assessed according to the force required for crushing. Results: All study specimens showed positive bacterial growth under anaerobic conditions. The bacterial cultures revealed decrease in the bacterial count in Group 2 i.e. Irradiated group (I) when compared with Group 1 i.e. Non-irradiated group (NI). The results obtained from computerized Universal Testing Machine showcased varying values required to crush the sub-gingival calculus samples suggesting variation in mineralization of each sample. The correlation between mineralization and viable anaerobic bacterial count revealed an inverse relation. Conclusion: Sub-gingival calculus plays a key role in harbouring pathogenic anaerobic bacteria, owing to its porous ....