orofacial infection uses of antibiotics in dentistry

1. Orofacial infections
Uses and abuses of antibiotics in
dentistry
Made by
Dr.Dalia Omar Ahmed

2. Antibiotics is
is a chemical compound that inhibits or abolishes the growth
of micro organisms. such as bacteria. fungi, or protozoans.
Anti-bacterial antibiotics can be categorized based on
their target specificity:
1- narrow-spectrum antibiotics target particular types of bacteria, such as
Gram-nega-tive or Gram-positive bacteria.
2-broad-spectrum antibiotics affect a wide range of bacteria.

3.  Also categorized according to there effect on the
bacteria :
1. Bactericidal ... Destroy bacteria. Not used in immunosupressed patients
and life – threatening diseases such as endocarditis or meningitis.
2. Bacteriostatic ... Prevent bacteria from multiplying.
Also categorized according to method of administration
to:
1. Orally administered antibiotics.
2. Intravenously (used in deeply seated systemic infections and serious
conditions )or intra muscular administration.
3. Topical as eye drops or ointments .

4. Effectiveness of the Antibiotics is
effected by :
 Location of the infection.
 Ability of the antibiotic to reach the site of infection.
 Ability of the microbe to inactive or excrete the antibiotic
 Antimicrobials : drugs used to treat infections they
are
 Antibacterial ( often called antibiotics since many are derivatives of naturally
produced chemicals)
 Antiviral.
 Antiprotozoal.
 Anthelmintic.

5. Principles of prescribing antibiotics.
 1. Make a good diagnosis of bacterial infections ( fever not always imply
bacterial infection) .
 2. In all serious infection, take a specimens (blood, pus,sputum, urine, swabs)
for cultur and antibiotic sensitivity testing.
 3. Consider the need for antibiotic therapy at all example: many skin
infections antibiotic do not treat it.
 4. Of a culture has been taken and there is a need for urgent therapy before
results are available , empirical antibiotic therapy maybe necessary in all
seriously ill patients but it may prevent accurate diagnosis of the infection or
organism identification., this is important when there is repeated failure to
respond to the treatment or partial response to a chosen antibiotic.
 5. Select the most appropriate drug using the following factors

6.  A. The organism and what antibiotic it is sensitive to this usually based on microbiological
sensitivity test.
 B. Patients age, renal and hepatic function, allergy, diminished resistance to infection (
malnutrition, malignancy, immunosuppression by drugs such as corticosteroids) pregnancy or
genetic factors all of these can influence the choice of antibiotic.

 C. The severity of the infection: this Well influence the choice of the antibiotic and its route
of administration, some antibiotics not absorbed when given orally (aminoglycosides) In
seriously ill patients parentral administration is more reliable.
 D. The site of the infection: antibiotic often do not penetrate abscess cavities well and
usually they require drainage some antibiotics can’t penetrate the site of infection (e.g
aminoglycosides inappropriate for meningitis).
 E. The presence of foreign body ex: prosthetic heart valve a piece of glass in a skin wound its
likely to diminish or prevent the effect of the antibiotic.

7.  6. Monitor the success of the therapy clinically and or microbiological by
culture.
Some antibiotics with serious concentration- related toxicity also require
monitoring of the plasma concentrations ex: Gentamicin .
 7. Combination of antibiotics are occasionally used :
a. In mixed infection --- peritonitis.
b. When two antibiotic produces greater effect (Synergism). Ex penicillin +
gentamicin to treat infective endocarditis.
c. When the organism is unknown --- broad spectrum coverage is required ex :
septicaemia.
d. To prevent development of antibiotic resistance to one type asin ex:
ttuberculosis.

8.  8. Antibiotic also used as prophylaxis occasionally. Example: as in dental
procedures at risk of infective endocarditis or close contact with a patient
who have meningococcal meningitis the duration of prophylaxis use is brief
usually 24 hours or less.
Reasons not to use antibiotic without consideration:
1. Risk of missing alternative diagnosis.
2. Adverse reaction .
3. Promoting antibiotic resistance.
4. Expensive.

9. Uses of Antibiotics are :
 Curative treatment ( is the primary aim of antibiotic ) used when
:
 1. Infections can’t be treated with surgery ( incision & drainage)
 2. As supplementary to surgery in case of effected general conditions or
risk to form an abscess.
 3. In osteomyelitis and
Curative
treatment
Prophylactic
treatment
Not routinely
systemic
antibiotics
treatment

10. Prophylactic treatment:
 Starts 1 hour prior surgery used on the following indications:
 1. Absolute indications. 2.Conditional indications
Absolute indications:
1.Diabetics subjected to major surgery ----- “Juvenile diabetes >always .
----- “Senile diabetes > sometimes ( consult consult
patients general practitioner)
2. Immunocompromised patients ( cortisone immunosuppressive treatment).
3. Patients with previously subjected to radiation treatment in the head and neck region.
4. Closure of Oro-antral fistula.
5. Bone transplantation oral surgery .
6.Operation/ extraction in patients subjected to acute infection .
7.Patients who have/had rheumatic fever .
8.Patient with congenital or acquired heart disease (endocarditis, artificial heart valve
prothesis).
9. Replantation of ex articulated teeth

11. Conditional indications:
 1.General weak patients ex: patient in dialysis treatment or leukaemia.
 2.Treatment of complicated jaw fractures.
 3.Surgical intervention Causing huge bone cavities.
 4.Extensive soft tissue lesion of the mouth floor causing communication to
sputum parapharyngeum.
 5.tooth transplantation,reattachment.
 6.Insertion of titanium-implants.

12. Not routinely systemic antibiotic
treatment
 1. Trans-alveolar extraction .
 2. Pericoronitis .
 3.Fluctuating and well defined abscess .
 4.periodontal surgery .
 5.Root resection .
 6.Uncomplicated jaw fractures.
 7. Removal of the 3rd molar.

13. Antibiotic s some time is used in a wrong
manner ( Antibiotics misuse or abuse)
 Common form of antibiotics misuse is
 1. Failure to take the entire prescribed course.
 2. Failure to rest for a sufficient recovery time to allow clearance of infecting
microorganisms .... Both can form a new bacterial population with antibiotic
resistance.
 3. Common form of antibiotic abuse is to prescribe it for the wrong infection
example: giving antibacterial antibiotic treatment for viral infections.
 4. In patients taking multiple medications drug interactions should be
considered.

14. Side effects of antibiotics:
 The side effects depend on :
1. The antibiotic used 2. Microbial organism targeted.
Adverse effects can range from nausea to major allergic reactions as
photodermatitis.
one of the most side effect is diarrhoea sometime is caused by bacterium
Clostridium difficult, which results from the antibiotic disrupting the normal
balance of the intestinal flora, ( which may be alleviated by ingesting probiotics )
. Other side effects can result from interaction of the antibiotic with other drugs,
such as elevated risk of tendon damage from Administration of a quinolone
antibiotic with a systemic corticosteroid. Also some not so many antibiotics can
interact with the efficiency of birth control pills