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Antibiotics in Dentistry

Antibiotics are a powerful weapon in the war on harmful bacteria in all parts of medicine and dentistry is no exception.  


There are several types of infection that are common in dentistry, but the most common types are periodontal abscess (infection of the gums) and endodontic abscess (infection of a tooth).  Antibiotics are part of the treatment of both of these kinds of oral infections.  

Much of the change from the old days when dentistry was often painful to now when pain during treatment is quite uncommon has to do with use of antibiotics.  For example, in the old days, when a patient presented at the office with swelling, local anesthetic was often attempted in the area, but with very little effect due to the chemistry of the infection.  Then the swollen area was incised (cut) and a drain (small piece of rubber) was placed to allow the area to drain for a few days.  These days the procedure consisting of incision and drainage is not very common.  Usually antibiotics will bring down the swelling without the pain and inconvenience of incising and draining the abscessed and swollen area.  In this way, the area is not treated with any instruments until the swelling is much reduced or gone making it so local anesthetic is effective when the treatment is done.  Treatment in this way greatly reduces the pain or discomfort to the patient during treatment for an abscess.  As well, during the incision and drainage procedure, nerves can be permanently damaged so the procedure has to be done with some precision which is often impossible because the patient usually feels most of it.

There are many antibiotics that can be effective in treating dental infection.  They have varying effectiveness against different types of infection and do not always have the same effectiveness in every patient.  The most common antibiotic to use against dental infection is Penicillin.  This has been the case since the 1940’s, but since that time the dosage that is effective in most people has increased sharply.  Dental infections are becoming more resistant to all antibiotics, including Penicillin.  As well, there is difference of opinion regarding what dosage of Penicillin is best.  In fact, you will find that the dosage on either side of the Canada /US border is substantially different, with the Canadian dose being only 60% of the US dose.  Somehow I find it hard to imagine that bacteria causing a dental abscess have any idea which side of the border the abscess is on.  Suffice it to say that there are differing dosages and different antibiotics used in different places for different kinds or stages of abscesses.  

Sometimes when we have prescribed an antibiotic for a dental abscess, the patient has little effect from it and calls back a couple of days later to tell us it has not worked.  We will change to another type of antibiotic that has more activity against the bacteria.  Usually this is all that is needed to have success in reducing the size of the abscess so the tooth can be treated or extracted.  Sometimes patients express disgust that the “good stuff” was withheld until after several more days of pain have elapsed.  However, the more powerful antibiotics against dental infection have more chance of causing nasty and fairly long lasting side effects, and Penicillin or something very similar to it usually work very effectively with a reduced chance of these kinds of troubles.

 In dentistry as well as the rest of the medical field, antibiotics have to be used as they are prescribed.  There is quite a bit of science involved in figuring out what dosage for how long is most effective against the particular type of infection one is fighting.  Taking some other dosage runs the risk of making the antibiotic ineffective and prolonging the pain of the abscess or having it return very quickly.  There are problems with reducing the effectiveness of the medication for all patients because of this type of misuse of antibiotics by some patients.  Having two or three bottles with half a dozen antibiotic pills in each of them kicking around in your medicine cabinet is not something to be proud of.  

 It takes many years of careful science and evaluation to develop an antibiotic.  Antibiotics currently available are a gift from the science of the past to us.  We have to use them wisely.  When used wisely, they are a tremendous aid to effective dental treatment and reduction of pain in dental treatment.

This article was written by Dr. Mike Christensen and published in the Daily Miner and News, and Enterprise. Local Kenora News Publicatons (1998-2006)

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