Microbiology In Odontogenic Infection

Microbiology in odontogenic infections
Most odontogenic infections contain mixed aerobic and anaerobic bacteria. predominant bacterial species present in oral cavity are maunly Streptococcus , Peptostreptococcus, Veillonella, Lactobacillus, and Actinomyces . 11,12 The mixed aerobic-anaerobic composition of the bacteria involved in suppurative odontogenic infections is thought to be important in the pathogenesis of infection. if bacteria involved in mixed odontogenic infections are isolated in pure culture and transferred to healthy animals, they are often incapable of producing disease.10 therefore synergy of aerobic and anaerobic bacteria is thought to be necessary for the development of infection. the respiration of aerobic bacteria depletes the local environment of oxygen, creating
Aerobic gram negative bacilli are uncommon in healthy adults,. The microflora's bacterial composition is slightly different in patients with healthy tissue and patients with dental caries, gingivitis, and periodontitis. Increase in number of Streptococcus mutans' is seen in patients with dental xaries . 13,14 As dental caries progresses , the bacteria invade the dental pulp, an inflammatory reaction results in necrosis and a lower tissue oxidationreduction potential. At this stage, the bacterial flora change from predominantly aerobic to more anaerobic flora. Anaerobic gram-positive cocci (Peptostreptococcus) and anaerobic gram-negative rods (Bacteroides, Prevotella, Porphromonas and Fusobacterium) predominate. In gingivitis and periodontitis, the predominant subgingival flora are anaerobic gram negative bacilli.15 In patients with pericoronitis, the predominant species recovered are Peptostreptococci, Fusobacterium, and Bacteroides, while Prevotella intermedia, Fusobacterium, and Capnocytophaga are frequently recovered from periodontal