Antibiotics for use in Endodontics

ANTIBIOTICS FOR USE IN ENDODONTICS( part 1 ):-
Pulpal invasion begins with a mixed infection of aerobes & anaerobes.as infection continous,oxygen is depleted,& obligate anaerobic bacteria &facultative bacteria predominate.BACTERIAL PATHWAYS TO PULP:-
1.Caries
2.Periodontal disease
3.Fractures
4.Dental tubules not covered by cementum
5.Anachoresis

ANTIBIOTICS:

• Antibacterial agents,commonly called ANTIBIOTICS are very useful because they kill bacteria without damage to the host.these drugs attack cell structure & metabolic pathways unique to bacteria & not shared with human cells.


• systemic ANTIBIOTICS are used in frequently in DENTISTRY.some say they are overused.although this is probably true,it is also difficult to tell when infection might spread to cause life threatening problems, such as:


• LUDWIG'S ANGINA,SWELLING reaching into mediastinum,BRAIN ABSCESS & ENDOCARDITIS all of which have developed as sequelae of ROOT CANAL THERAPY.


• It is probably wise to use systemic ANTIBIOTICS when & where there is a reasonable possibility of microorganisms beyond the ROOT CANAL. The IMMUNOLOGICALLY compromised patients should be considered an indication for ANTIBIOTIC THERAPY,regardless of condition of canal.

CLASSIFICATION:-

ANTIBIOTICS may be classified into two main categories:

1.Rapid killing ANTIBIOTICS

• PENICILLINS & CEPHALOSPORINS


• METRONIDAZOLE


• FLUROQUINOLONES

2.ANTIBIOTICS that slow protein synthesis

• ERYTHROMYSIN (macrolide)


• CLINDAMYCIN


• TETRACYCLINE

common examples of oral penicillin

• Penicillin V 500MG QID


• ampicillin 500MG QID


• amoxicillin 500MG TID/QID CEPHALOSPORINS:

1st generation:cephalexin 500MG QID
cefadroxil 500MG QID
2nd generation:cefuroxime 250 or 500MG BID
cefactor 500MG TID
3rd generation:cefixime 4ooMG daily
(dosage can vary with specific situations)

• Fast killing antibacterial agents are often called bactericidal ( PENICILLINS ,CEPHALOSPORINS & METRONIDAZOLE) commonly used against endodontic pathogens.


• PENICILLINS & CEPHALOSPORINS -kill by integrating into & weakening a newlymade cellwall.


• METRONIDAZOLE-impedes DNA manufacture

So antidiotics that fight bacteria by slowing their protein synthesis (bacteriostatic ANTIBIOTICS) are generally not given along with their bactercidal drugs.
ALLERGIES:-
Anaphylactic allergic reactions are rare with oral penicillins & cephalosporins,although possible.if allergic to penicillins, the patients should be allergic to cephalosporins as well & vice vers,because of close molecular structure.there is 10% of cross -reactivity between these groups. continued in my next post.