LO 11 Flashcards
Antibiotics
Describe the progression of dental infections
- Dental infections often follow similar pathways from beginning to end
- The organisms initially responsible for a dental infection are primarily gram-positive cocci
- After a short time, the gram-positive infection begins to include a variety of both gram-positive and gram-negative anaerobic organisms; this is termed a mixed infection
- Over time, the proportion of organisms that are anaerobic increases until it consists of predominately anaerobic flora
- The choice of antibiotics for an infection depends on where it is in its evolution
What are the factors that determine the likelihood of a microorganism causing an infection
- Disease-producing power of the microorganism (virulence)
- Number of organisms present (inoculum)
- Resistance of the host (immunologic response)
__________ involves exposing the organism to test antibiotics and determining whether the organism is sensitive or resistant
Sensitivity testing
___________ and ____________ is the only way to be sure a drug will kill or inhibit the growth of the infecting microorganisms
- Culturing
- Sensitivity testing
The best defense against a pathogen is __________
host response
*When this defense is lacking, the need for antimicrobial agents is more pressing
What is the rule for antimicrobial therapy in dentistry?
- No simple rule has been developed to determine whether antimicrobial therapy is needed in dentistry; many infections do not require it
- Most patients, without immune function deficiencies, in whom drainage can be obtained, do not need antibiotics to manage their dental infections
Define Antibacterial agents
Substances that destroy or suppress the growth or multiplication of bacteria
Define Antibiotic agents
Chemical substances produced by microorganisms that have the capacity, in dilute solutions, to destroy or suppress the growth or multiplication of organisms or prevent their action
Define Bactericidal
- Ability to kill bacteria
- Irreversible; if the bacteria are removed from the drug, they do not live
Define Bacteriostatic
- Ability to inhibit or retard the multiplication or growth of bacteria
- Reversible; if the bacteria are removed from the agent, they are able to grow and multiply
Define resistance
The natural or acquired ability of an organism to be immune to or resist the effects of an antiinfective agent
Define Superinfection/suprainfection
Infection caused by proliferation of microorganisms different from those causing the original infection
What are the indications for antibiotics in dentistry?
- Therapeutic (abscess)
- Pre-medication** – antibiotic prophylaxis (no current infection)
List the general considerations for antibiotics
- only consider AB if patient is immune compromised or lymphadenopathy is detected in a healthy client.
- course of Tx should be 1 week until finished
- Minimum 9 days between appt’s pre-meds are required
- Cross-allergenicity within each group
- Increase AB resistance if taken too often / not completed Tx course
- Cost !!
- Rx the narrowest spectrum as possible.
List the general adverse reactions to antibiotics
- Superinfection/suprainfection
- AB can decrease efficacy of oral contraceptives
- AB can increase warfarin efficacy = warfarin toxicity
- G.I distress - pseudomembranous colitis (c.diff), vomiting, upset GI, etc.
- During pregnancy, only penicillin + clindamycin are “safe”