Thurs., Sept. 2, 1999

Dear Dr. Mady: When I was a child, I had rheumatic fever. I have never had any problems since that were associated with it. Recently my new dentist said that I need to take antibiotic pre-medication prior to any future dental treatment, because of my past rheumatic fever. Is this normal protocol for people like myself and is it really necessary?.-Joan in Harrow

Dear Joan: There does exist a relatively small but important group of individuals who might require antibiotic pre-medication before invasive dental treatment. The whole purpose of this is to prevent a very serious and potentially fatal condition known as Subacute Bacterial Endocarditis (SBE).

There are more than 300 different types of bacteria present in the human mouth. Certain dental procedures that induce gingival or mucosal bleeding can allow these bacteria to enter into the blood system and ultimately arrive at the heart.

In most individuals this is not a problem. If, however, the heart has any type of damage from congenital defects or past problems such as rheumatic fever, these blood-borne bacteria may lodge on abnormal heart valves, around prosthetic heart valves or on the heart lining near congenital heart defects. This is where a life threatening infection can develop and the use of antibiotics prophylactically prior to dental treatment is the logical way to prevent this bacteremia.

The category of risk to which a patient belongs depends largely upon the specific condition present.

The highest risk category includes individuals with artificial heart valves, a history of previous endocarditis, complex cyanotic congenital heart disease, or surgically constructed pulmonary shunts or conduits.

At moderate risk are patients with acquired valvular dysfunction (often caused from rheumatic fever), other congenital cardiac malformations, mitral valve prolapse with valvular regurgitation, certain types of heart murmurs, and with hypertrophic cardiomyopathy.

There are certain conditions that do not necessarily need antibiotic coverage but each situation has to be evaluated individually due to the fact that they may need special attention.

These include, but are not limited to, mitral valve prolapse without valvular regurgitation, innocent or physiological heart murmurs, isolated atrial septal defects, rheumatic fever without valvular dysfunction, previous Kawasaki disease, surgical repair of atrial or ventricular septal defects, coronary bypass surgery and the presence of a pacemaker.

There is one controversial group of individuals that may need antibiotic premedication but not always. These are people with surgically placed artificial or prosthetic joints. Some of these people may develop infection at the site of the replaced joint. Those at risk are the ones that are immuno-suppressed or immuno-compromised for one reason or another.

Also, patients who are hemopheliacs, insulin-dependent diabetics, malnourished, with rheumatoid arthritis or systemic lupus erythmatosus, and those with previous prosthetic joint infections have the potential for complications. If anyone has had joint replacement in the past two years or any of the above conditions, they should check with their dentist and physician to see if pre-med is required.

Although not all dental procedures require pre-med for susceptible patients, most invasive ones do. These procedures include routine teeth cleaning (scaling), fillings at or below the gum line, tooth extraction (removal) and other surgical procedures. Procedures that do not require antibiotic premedication include toothbrushing, natural loss of primary teeth, adjustment of orthodontic appliances, oral examinations, impression taking, fillings above the gums, placement of sealants, and most anesthetic injections.

Endocarditis and other systemic infections caused by bacteremia may occur in spite of antibiotic prophylaxis. If, following treatment, the patient experiences unexplained fever, lethargy, weakness or malaise they should contact their dentist and/or physician immediately.

Even in the absence of dental procedures, poor oral hygiene or gum and tooth infections may produce bacteremia.

Therefore, it is essential for anyone at risk practice meticulous oral hygiene and home care in addition to regular preventive dental care.

The antibiotic regimen for prophylaxis for both endocarditis and prosthetic joints has been modified in recent years. Previously, patients were required to take a certain amount of a specific antibiotic before and after dental appointments but now they only have to take the medication before the treatment.

If you fall into one of the risk categories, this protocol is extremely necessary. Notify your dentist and he will advise you as to which antibiotic to take, the exact dosage and when. It could be a matter of life or death.
_____________________________________________________________________________________________
This column is reprinted with the permission of the author and The Windsor Star. "Ask the Dentist" is written by Windsor dentist (and ECDS member), Dr. David Mady Jr.. The column appears the first Thursday of each month in the Windsor Star. Readers with questions can write to "Ask The Dentist", c/o The Windsor Star, 167 Ferry St., Windsor Ontario, N9A 4M5