Gram-negative facultatively anaerobic coccobacillio Normal flora in the mouth found in plaque biofilms, saliva and mucosa o Causes dentoalveolar infections, acute sialadenitis (salivary gland infection), infective endocarditis.
Gram-negative microaerophilic or capnophilic (CO2 dependent) coccobacilli- fimbria, many virulence factors - in perio pockets; implicate in aggressive Perio disease (localized & general) - copathogen w cervicofacial Actinomyces
Gram-negative facultatively anaerobic coccobacilli (formerly Bacteriodes)- Plaque biofilms in both healthy & periodontitis ppl
· carbon dioxide-dependent, Gram-negative rodso Found in plaque, mucosal surfaces, saliva o Infections in immunocompromised, destructive periodontal disease o Some strains produce IgA protease.
· Gram-negative anaerobic pleomorphic rods, non-motile; degrades collageno Can be normal flora or significant problem in PD o Gingival crevice and subgingival plaque in small no.s o Ass. w chronic periodontitis and dentoalveolar abscess.
Gram-negative pleomorphic anaerobic rods,o May be part of normal flora. o Also found in periodontal pockets, dental plaque, chronic periodontitis and dentoalveolar abscess.
Gram-negative anaerobic- Can produce ammonia and hydrogen sulfide – “rotten egg”; odor causing in halitosis. - Normal gingival crevice and tonsils. - Also in periodontal infections, acute ulcerative gingivitis, dentoalveolar abscess.
· Gram-negative filaments anaerobes.o Found in dental plaque. No known disease association.
· Gram-negative anaerobic bacilli.o Found in the gingival crevice. Possible involvement in destructive periodontal disease.
· Gram-negative anaerobic rods.o Found in the gingival crevice. No known disease association.
· Motile Gram-negative anaerobic helical/spirillum.o Difficult to culture. o Found in the gingival crevice; closely associated with acute ulcerative gingivitis, destructive periodontal disease (degrades collagen).
The predominant cultivable species in subgingival plaque are Actinomyces, Prevotella, Porphyromonas, Fusobacterium, Veillonella.
Bact hydrolyze sucrose and make polysaccharides like:· dextrans make a sticky surface for other bugs · glucans – used by bacteria to store energy · fructans/levans – storage forms made by bugs – when broken down, plaque gets more acidic
MUST HAVE bact for PD and caries
- Bugs are NEGATIVELY charged, as is tooth surface1. Ca+2 ions make a bridge between enamel and pellicle and bug 2. -bact use fimbriae, pili or flagella to bind to glycoproteins (salivary) of pellicle
·communication--> all act as one organism!- Control genes related to extracellular polysaccharide production - Reduce metabolism (for bacteria at the bottom) - Control production of virulent factors, incl. drug-destroying genes.
- Adsorption of host and bact to the tooth surface forms the acquired salivary pellicle.
o Anaerobic, gram-positive bacilli are found in the range of 5%-14%
- adult periodontitis: microflora changes from aerobic, non-motile, Gram + cocci to anaerobic, motile, Gram - bacilli
o In localized or generalized aggressive periodontitis there is an increase in Actinobacillus either alone or synergistically with Capnocytophaga spp. and Porphyromonas gingivalis.
o In necrotizing ulcerative gingivitis, Fusobacterium nucleatum and oral spirochetes (Treponema spp.) predominate.