This document discusses the use of antibiotics in oral and maxillofacial surgery. It begins with an introduction and overview of antibiotic classification, mechanisms of action, principles of use, and indications. It then covers specific topics like empirical therapy, combination therapy, special patient populations, surgical wound classification, antibiotic resistance, and newer antibiotics. The key points are that antibiotics are generally used to treat established infections, as prophylaxis for high-risk procedures, and that principles of prudent use include narrow-spectrum therapy based on culture and sensitivity testing when possible.

1. BY:-
Dr. SAUVIK SINGHA
PG-I yr STUDENT
Dept of oral and maxillofacial surgery
HDC&H

2.  INTRODUCTION
 HISTORY
 CLASSIFICATION
 MOA
 PRINCIPLES
 ANTIOBITOCS IN OMFS
 SPECIAL CONDITIONS
 RESISTANCE
 NEWER ANTIBIOTICS
 REFERENCE

3. WHAT IS AN
ANTIBIOTIC????

9. C
L
A
S
S
I
F
I
C
A
T
I
O
N
ON THE BASIS
OF
ON THE BASIS OF PREPARATION
NATURALLY OCCURING-
PENICILLIN
CEPHALOSPORIN
ERYTHROMYCIN
SYNTHETIC-
SULPHONAMIDES
ON THE BASIS OF FAMILY
PENICILLINS
CEPHALOSPORINS
TETRACYCLINS
SULPHONAMIDES
AMINOGLYCOSIDES-GENTAMYCIN,
NEOMYCIN,STREPTOMYCIN
MACROLIDS-
ERYTHROMYCIN,AZITHROMYCIN,CLARI
THROMYCIN
ON THE BASIS OF SPECTRUM
OF ACTIVITY
NARROW-
PENICILLIN, STREPTOMYCIN
BROAD-
AMPICILLIN, TETRACYCLIN,
CHLORAMPHENICOL
EXTENDED-
SEMISYNTHETIC PENICILLINS
NEW CEPHALOSPORINS
AMINOGLYCOSIDES
BACTERIOSTATIC-
SULPHONAMIDE
CHLORAMPHENICOL
TETRACYCLINE
ERYTHROMYCIN
ETHAMBUTOL
BACTERICIDAL-
PENICILLIN
CEPHALOSPORIN
AMINOGLYCOSIDES
VANCOMYCIN
CIPROFLOXACIN
ISONIAZID
RIFAMPICIN
COTRIMOXAZOLE
ON THE BASIS OF
ANTIBIOTICS OBTAINED
FROM
FUNGI-
PENICILLIN
CEPHALOSPORIN
BACTERIA-
BACITRACIN
POLYMYXIN B
ACTINOMYCETES-
CHLORAMPHENICOL
AMINOGLYCOSIDES
TETRACYCLINS

13. INDICATIONS
Treatment of established infections;
• infections that persists inspite of local measures
• where there is signs of systemic involvement eg.submandibular
lymphadenopathy and fever
• when surgical access is difficult e.g severe trismus
• when there is a diffuse , spreading infection eg.facial cellulitis
Prophylaxis against infections:
- Immunocompromised patient
- Surgical procedures with a high likelihood of infections
• Maxillofacial trauma
• Major or difficult surgery
• When the consequences of infections are serious
• Infective endocarditis
• Orthopaedic joint prosthesis

14. Principles for choosing antibiotic
• State of host defence mechanism
• Identification of the causative organism
• Determination of antibiotic sensitivity
• Use of a specific, narrow-spectrum antibiotic
• Use of the least toxic antibiotic
• Patient drug history
• Use of a bactericidal rather than a bacteriostatic drug
• Use of the antibiotic with a proven history of success
• Cost of the antibiotic
• Encourage patient compliance

16. DIFFERENT METHODS
Disk Diffusion Method
Dilution Method
Serum Killing Power
Automated Methods

17. LEAST TOXIC
DRUGS
MORE TOXIC
DRUGS

20. Use of bactericidal rather than
bacteriostatic drugs
• Advantages:
• Less reliance on the host resistance
• killing of the bacteria by the antibiotic itself
• Faster results
• Greater flexibility with dosage intervals.
• Used especially when the host defenses are low.

21. Use of the antibiotic with a proven
history of success
- Critical observation of the clinical effectiveness over a
prolonged period -----assessment of
• Frequency of treatment success and failures
• Frequency of adverse reactions
• Frequency of side effects
• Standards for use

22. COST OF THE ANTIBIOTIC:-
• Difficult to place a price tag on health.
• In some situations, more expensive antibiotic is the
drug of choice.
• In other situations, there may be a substantial
difference in price for drugs of equal efficacy.
• Surgeon should consider the cost of the antibiotic
prescribed

23. Encourage patient compliance
Dosage interval that encourages compliance
• OD 80%
• BID 69%
• TID 59%
• QID 35%
Non-compliant start feeling better
• 3-5 days 50%
• >7 days 20%
Antibiotic that would have the highest compliance
would be the drug given OD for 4 or 5 days.

26. (3-4×MIC)
(4×t1/2)

32. EMPERICAL
THERAPY
WHEN TO START
RISK OF SURGICAL INFECTION
IS HIGH
SIGNIFICANT CONTAMINATION
DURING SURGERY HAS
OCCURRED
CRITICALLY ILL PATIENTS
 SEVERE SEPSIS OR SEPTIC
SHOCK
WHEN TO
START SHORT COARSE (3-5 DAYS)
STOP IF THE PRESENCE OF A
LOCAL SITE OR SYSTEMIC
INFECTION IS NOT REVEALED

33. COMBINATION
THERAPY
IF PATIENT
CONDITION
DOESNOT
IMPROVE
AFTER INITIAL
THERAPY
IF INITIAL
THERAPY
FAILED

34. COMBINATION ANTIBIOTIC THERAPY
 RATIONALE
• To have an additive synergistic effect.
• In mixed infections when bacteria are sensitive to
different drugs.
• To achieve delay in development of resistance.
• To decrease the incidence of adverse reactions to an
individual drug , another drug is added so that the doses
of individual drug can be reduced and possible toxic
effects can be avoided
• To reduce the cost of therapy

35. WHEN DOES THE USE OF
ANTIBIOTICS ARISE IN
MAXILLOFACIAL SURGERY???
• SURGICAL EXTRACTIONS
• SURGIAL MANAGEMENT OF LESIONS
• SPACE INFECTIONS
• TRAUMA
• ORTHOGNATHIC SURGERY
• OSTEOMYELITIS

41. Immunosuppression determined by ANC(Absolute neutrophil count)
ANC<500ml indicates severe neutropenia

59. DIABETIC PATIENT
• Antibiotic prophylaxis.
• Amoxicillin is better choice.
• Uncontrolled diabetes.
• PRECAUTION;Gatifloxacilin- causes both
hypoglycemia and hyperglycemia.
• Compared with macrolides- Gatifloxacilin
4.3 times higher risk hypoglycemia
16.7times higher risk hyperglycemia

62. CLASSIFICATION OF SURGICAL
WOUNDS
Type I. Clean wounds (no opening of mucosa in the oral cavity): Confirmed
infection rate of 1 to 4%. Antibiotic prophylaxis not required.
Type II. Clean-contaminated wounds (opening of mucosa in the oral cavity,
insertion of dental implants or intervention on inflammatory pathology):
Confirmed infection rate of 5 to 15%. These require antibiotic prophylaxis with
drugs covering Gram positive and anaerobic micro-organisms.
Type III. Contaminated wounds (oncological pathology in which there is
simultaneous action on the oral cavity and the neck): Confirmed infection rate of 16
to 25%. Antibiotic prophylaxis must be carried out to cover Gram negative
organisms whose coverage in clean and cleancontaminated surgeries is disputed.
Type IV. Dirty and infected wounds. Confirmed infection rate of above 26%.
These always need adequate antibiotic treatment.

75. DANGERS OF ANTIBIOTIC MISUSE
• Widespread sensitization of populace
• - Changes of normal flora of body --> overgrowth of
resistant organisms
• - Masking serious infection without eradicating it (e.g.
abscess)
• - Direct Drug Toxicity
• - Development of drug resistance
• - Alteration of individual and hospital bacterial ecology
• - Possibility of antagonism (ie. penicillin and tetracyclin)
• - Higher cost of treatment
• - False sense of security

77. DRUG RESISTANCE
• Resistance of a microorganism
to an antimicrobial agent to
which it was previously sensitive
• Resistant organisms are able to withstand
attack by antimicrobial medicines so that
standard treatments become ineffective and
infections persist and may spread to others

78. Intrinsic
• Drug target is not present in the bacteria’s
metabolic pathways
Acquired
• Mutation
• Transfer of genetic material from resistant to
susceptible organisms (plasmids, transposons,
bacteriophages)

79. Main factors contributing to
resistance are:
• Excess antibiotic usage
• Incorrect use of broad spectrum
agents
• Incorrect dosing
• Non compliance

83. NEWER ANTIBIOTICS
1. MEROPENEM
• It is a beta-lactam, belongs to the subgroup of
carbapenem.
• Ultra broad spectrum injectable antibiotic.
• Inhibits bacterial cell wall synthesis.
• Action against gram positive and gram
negative bacteria and some anaerobic
bacteria.
• Administered intravenously.

84. 2. CEFEPIME
• Fourth generation cephalosporin.
• Extended spectrum of activity against gram
+ve and gram –ve microbes compared to third
generation cephalosporins.
• Administrated intramuscularly or
intravenously dose – 1 gm to 2 gm every 12
hourly.

85. 3. QUINUPRISTIN / DALFOPRISITIN (SYNERCID)
• Synercid is the brand name of combination of quinupristin and
dalfopristin antibiotics.
• These are semisynthetic pistinamycin derivatives.
• Active against methicillius sensitive staphylococcus aureus,
group A streptococci, Enterococcus faecium.
• 500 mg strength of synercid contains 150 mg of quinupristin and 350
mg of Dalfopristin.
• Administration – intravenously.

86. 4. LINEZOLID
• New antibacterial drug belongs to class oxazolidones.
• Inhibits protein synthesis – 70s ribosomes.
• Active against methicillin resistant and sensitive
staphylococci, and streptococci enterobacteria
faecalis.
• 400 – 600 mg orally twice daily (12 hrly) parenteral
route for severely ill patients. Dosage is same as that
of oral route
• Metabolized by oxidation and hence can safely
used in renal failure.

87. 5. MOXIFLOXACIN
• It is a synthetic fluoroquinolone agent.
• Inhibits topoisomerase II and IV, there by affects
the replication and repair of bacterial DNA.
• It is active against following organisms :
• Step. aureus, staph Epidermides, strepto
pneumonias, H. influenzae, Klebsiella, Enterobacilus,
mycobacterium, Bacillus anthracis.
• Administrated both oral and intravenous route.
• Dose : 400 mg daily orally or i.v. infusion.

88. 6. GATIFLOXACIN
• It is a fourth generation fluro-quinolone agent.
• Greater affinity for topoisomerase IV.
• Active against gram +ve cocci.
• Oral and intravenous route.
• Dose – 200 to 400 mg orally or i.v. once daily (+½
shown)
• Active against – Streptococcus pneumonias.
• Chlamydia pneumonias.

89. Bleomycins (BLM)
• Natural glycopeptidic antibiotics produced by
Streptomyces verticillus
• Efficacy against tumors
• Mainly used in therapy in a combination with
radiotherapy or chemotherapy
• Commonly administered as Blenoxane, a drug
that includes both bleomycin A2 and B2.

91. WHEN THE QUESTION OF USING ANTI BIOTICS ARISES IN
MAXILLOFACIAL SURGERY????
• SURGICAL EXTRACTIONS
• SURGIAL MANAGEMENT OF LESIONS
• SPACE INFECTIONS
• TRAUMA
• ORTHOGNATHIC SURGERY
• OSTEOMYELITIS

92. [ ASIAN J OMFS : VOL 18 : NO. 4 : 272-278 ]
MOST ORAL INFECTIONS ARE ODONTOGENIC IN ORIGIN
SEQUELAE OF DEEP CARIOUS LESION / PERIODONTAL /
PERICORONAL INFECTIONS
MANAGEMENT
EXTRACTION / ENDO TREATMENT
/ SURGICAL DRAINAGE
WITHOUT ANTIBIOTICS

93. CONCLUSION
UNCOMPLICATED EXTRACTION,SURGERIES
+
OTHERWISE HEALTHY
LOW INFECTION RATE
ANTIBIOTICS NOT NEEDED
[ JIDA VOL.69 : SEPT-DEC 1998 : 274 – 277]

94. CONCLUSION
• Antibiotics are used to treat infections and are
also responsible for making them more
difficult to treat because of their misuses and
development of resistance. The only way to
keep antibiotics useful is to use them
appropriately and judiciously.

95. TAKE HOME MESSAGES!!!
• NEVER ACCEPT CONCEPT OF ANTIBIOTICS ON DEMAND
• NEVER USE A BROAD SPECTRUM ANTIBIOTICS WHEN NARROW
SPECTRUM IS INDICATED
• NO LONG COURSE OF ANTIBIOTICS
• NO NEED OF ANTIBIOTIC PROPHYLAXIS FOR SIMPLE SURGICAL PROCEDURES or
WHEN THERE IS LESS CHANCE OF POST SURGICAL INFECTION
• WHEN NO SIGNS OF INFECTIONS SUCH AS SWELLING,LYMPHADENOPATHY,
ELEVATED TEMPERATURE
• ALWAYS MAKE SURE THE SOURCE OF INFECTION IS ELIMINATED-
---EXTRACTION OF TOOTH ----- INCISION AND DRAINAGE

96. REFERENCES
Peterson

97. CHOOSE
WISELY
LIVE
WELL