Preventing an infection is crucial. Deep infection is a serious problem, affecting between 4% of primary and 15% of revision knee replacements.

There have been changing recommendations as to whether antibiotics should be mandatory for joint replacement recipients when undergoing dental work. Starting in 2012, the recommendations were modified to say that most people would not require antibiotics for routine dental work but that treatment may be given to people at the highest risk of infection.

How Implant Infection Occurs

The most common route of a bacterial infection into the body is through broken skin. While normal tissue can typically defend itself against the invading bacteria, the inorganic materials of a prosthesis (artificial body part) cannot. It is there that an infection can seed and cause damage to surrounding bone and tissue.

Another possible route involves oral infections and certain types of dental work. During a dental procedure (or any invasive medical procedure, for that matter), bacteria can often enter the bloodstream if the tissue is broken.

With little immune protection, any infection of a knee replacement and hip replacement can quickly turn serious, increasing the risk of complications and disability.

To avoid this, healthcare providers will often recommend a course of antibiotics before any invasive procedure. In this way, the natural bacteria on the skin or in the mouth will be dramatically suppressed.

While this would certainly be recommended in advance of major surgery, persons undergoing certain dental procedures may also be asked to take antibiotics before a procedure.

Current Dental Recommendations

There is often confusion (not only among patients but healthcare providers, as well) as to who should receive antibiotics before dental work. In the past, antibiotics were commonly administered for all dental procedures for the first two years following implant surgery.

That recommendation was then extended in 2009 from two years to a lifetime. However, there was a complete turnaround in policy only three years later.

In defending the decision, both the AAOS and ADA stated that there was no evidence to suggest that the routine administration of antibiotics reduced the risk of joint implant infection.

Similarly, the governing bodies were unable to endorse the use of oral antimicrobials prior to dental work and only reached consensus in recommending “healthy oral hygiene” as a means of ample protection.

Special Circumstances

This is not to suggest that antibiotics should be avoided or that there aren’t circumstances for which antibiotics may be appropriate. This includes major extractions (the pulling of teeth).

There are also certain individuals who are inherently at higher risk of infection due to either a severely weakened or abnormal immune response. In many cases, these individuals are less able to fight infection and to control it once it occurs.

When antibiotics are recommended, healthcare providers will typically prescribe oral amoxicillin (a form of penicillin) to be taken one hour before the dental work.

Rheumatoid arthritis, lupus, and other autoimmune disorders for which infection can trigger sometimes severe inflammation of the joints People with hemophilia (a bleeding disorder) or insulin-dependent (type 1) diabetes who are at increased risk of blood-borne infections Immune-compromised individuals. including organ transplant recipients, persons undergoing cancer radiation therapy, and people with advanced HIV (human immunodeficiency virus) infection Persons who have had a past infection of a joint implant

If you cannot tolerate oral antibiotics, your healthcare provider may recommend injectable cefazolin or ampicillin, which are injected within an hour of the procedure. If you are allergic to these drugs, clindamycin (either oral or injected) may be used.