Microbiological Characteristics of Veillonella spp. in the Composition of Endodontic Infections

A number of studies have confirmed that necrotic dental pulp does not cause periapical inflammation in the absence of microbial infection. The lack of blood circulation (and hence natural protection against invasion and colonization by oral microorganisms) leads to the infection of the microchannel system of the root canal dentin affecting the apical cement, the periodontal membrane and the lamina corticalis of the dental alveolus. Epidemiological studies indicate that up to 400 different microbial strains can be found in infected root canals, alone or more often in combinations. The results obtained from various studies have linked the presence of certain microorganisms with particular symptoms and nosological units, but there is still no definitive evidence for specificity of the bacterial species in different endodontic diseases. About 40 microbial strains are most commonly isolated from infected root canals and associated with apical periodontitis, with 10-12 of them being predominantly anaerobic species (Bacteroides, Prevotella, Porphyromonas, Fusobacterium, Veillonella). In this review, we will attempt to examine in detail the microbiological characteristics of anaerobic Gram-negative, non-spore forming bacteria of the genus Veillonella isolated in endodontic studies.