Microbiology - Endodontic Infections

Question 1

what types of bacteria is responsible for endodontic infections? (7)

Answer 1

• Bacteroides – gram negative (perio pathogen)
• Prevotella – gram negative (perio)
• Lactobacillus (caries)
• Oral Streptococcus (caries)
• Clostridium
• Fusobacterium (perio)
• Propionibacterium – found in the mouth, skin, hip joint infections etc

Question 2

what are the characteristics of E.faecalis? (7)

Answer 2

• Gram positive coccus
• Grows in aerobic and anaerobic conditions
• Aggregative phenotype – sticks together and forms biofilms
• Produces Superoxide’s which protect the bacteria
• Produces Lipotechoic acid which is proinflammatory
• Can penetrate into the dentine tubules and can reside in here and regrow to cause infection later on.
• Can develop a co-culture with c.albicans and they support one another (must use a combination of antimicrobials)

Question 3

how do we treat endo infections?

Answer 3

Combination of

Mechanical removal – endodontic treatment or extraction

Chemical removal

Question 4

what combination of chemicals is the most effective is inhibiting further endodontic infections.

Answer 4

EDTA and sodium hypochlorite