Pre-medication

Antibiotic Prophylaxis Guidelines

Many of you take an antibiotic prior to dental treatment. The purpose is to use an antibiotic prior to an infection to prevent an infection. It may be because of a mitral valve prolapse, certain types of implants, a joint replacement, or a heart murmur cause by a roughened heart valve. Antibiotic prophylaxis began initially to prevent bacterial endocarditis. Endocarditis is the collection and colonization of bacteria in the heart muscle. This leads to inflammation and deformation of the heart and is a life-threatening condition.

The American Heart Association published its first guidelines in 1955. Since then the guidelines have been modified several times. Each revision has tried to make the antibiotic regime simpler to increase patient compliance. The revisions also attempt to consider the fact that many bacteria present can eventually become resistant to the antibiotic therapy.

The guidelines for antibiotic prophylaxis was updated in 1990 and most recently in 1997. Before we review the most recent guidelines, as they relate to dentistry, please remember this. The original decision to use antibiotics to prevent infection was based on the assumption that if antibiotics are effective in treating an infection, they should be able to prevent them. Any studies to support this premise were done strictly in the laboratory and the primary mechanism for the prevention of endocarditis is not known.

The AHA guidelines are followed by most practitioners, but it is not unusual to find certain changes in dosages or medications made by particular doctors.

Antibiotic prophylaxis is recommended for the following:

High-risk category

Prosthetic cardiac valves, including bioprosthetic and homograft valves

Previous bacterial endocarditis

Complex cyanotic congenital heart disease (e.g., single ventricle states, transposition of the great arteries, tetralogy of Fallot)

Surgically constructed systemic pulmonary shunts or conduits

Moderate-risk category

Most other congenital cardiac malformations (other than above and below)

Acquired valvar dysfunction (eg, rheumatic heart disease)

Hypertrophic cardiomyopathy

Mitral valve prolapse with valvar regurgitation and/or thickened leaflets

Endocarditis prophylaxis is not recommended for the following:

Negligible-risk category (no greater risk than the general population)

Isolated secundum atrial septal defect

Surgical repair of atrial septal defect, ventricular septal defect, or patent ductus arteriosus

Previous coronary artery bypass graft surgery

Mitral valve prolapse without valvar regurgitation

Physiologic, functional, or innocent heart murmurs

Previous Kawasaki disease without valvar dysfunction

Previous rheumatic fever without valvar dysfunction

Cardiac pacemakers (intravascular and epicardial) and implanted defibrillators

If you identify with a condition in the high or moderate risk groups, then antibiotic prophylaxis is recommended for the following dental procedures:

Dental extractions

Periodontal procedures including surgery, scaling and root planing, probing, and recall maintenance

Dental implant placement and reimplantation of avulsed teeth

Endodontic (root canal) instrumentation or surgery only beyond the apex

Subgingival placement of antibiotic fibers or strips

Initial placement of orthodontic bands but not brackets

Intraligamentary local anesthetic injections

Prophylactic cleaning of teeth or implants where bleeding is anticipated

Restorative dentistry (operative and prosthodontic) with or without retraction cord

Local anesthetic injections (nonintraligamentary)

Intracanal endodontic treatment; post placement and buildup

Placement of rubber dams, postoperative suture removal, taking of oral impressions, and fluoride treatments

Placement of removable prosthodontic or orthodontic appliances and orthodontic appliance adjustment

Taking of oral radiographs

Shedding of primary teeth

If antibiotic prophylaxis is necessary, the following medications and dosages are recommended by the AHA:

 

Situation	Medication	Dosage
Standard prophylaxis	Amoxicillin	Adults: 2.0 g; children: 50 mg/kg orally 1 h before procedure
Unable to take oral medication	Ampicillin	Adults: 2.0 g IM or IV; children: 50 mg/kg IM or IV within 30 min before procedure
Allergic to Penicillin	Clindamycin or	Adults: 600 mg; children: 20 mg/kg orally 1 h before procedure
	Cephalexin or cefadroxil or	Adults: 2.0 g; children; 50 mg/kg orally 1 h before procedure
	Azithromycin or clarithromycin	Adults: 500 mg; children: 15 mg/kg orally 1 h before procedure
Allergic to penicillin and unable to take oral medications	Clindamycin or Cefazolin	Adults: 600 mg; children: 20 mg/kg IV within 30 min before procedure Adults: 1.0 g; children: 25 mg/kg IM or IV within 30 min before procedure

A complete listing of recommended procedures can be found at the American Heart Association website.