Dental Procedures after Total Hip Replacement
Taking antibiotics before dental procedures was common in order to stop infections in all people with joint replacements. However, more recent guidelines state that antibiotics only recommended in those who have had previous joint infections and/or have compromised immune systems.
In order to understand the relevance of dental procedures (or other invasive procedures) to total hip replacements, it is useful to first discuss the concept of bacteremia. A bacteremia is the presence of bacteria in the blood. This occurs as a result of a break in barriers (skin, gums, urinary tract, etc) that protect the body from bacterial invasion. This can occur after brushing your teeth, undergoing a dental or medical procedure, contracting pneumonia, or suffering from a urinary tract infection among other things. Transient bacteria in the blood stream (bacteremia) is common, and usually harmless. However, in certain instances the bacteria can lodge in another area of the body such as the kidneys, lungs, or prosthetic hip joint.
Total hip replacements can be especially vulnerable to bacteremia because the surfaces of the prosthesis are a desirable location for bacterial invasion and growth. Bacteria can travel through the blood from their primary cite of entry, such as the gums or urinary tract, to the location of the hip replacement. Once the bacteria reach the prosthesis, they can begin to grow further (colonize) on the surface of the prosthetic components resulting in a localized infection. This is more likely when a hip replacement is recent (<6 months old) because blood flow to the hip increases during the healing process.
In the past, it was recommended that all individuals with total hip replacements take an antibiotic prior to undergoing a dental procedure in order to prevent bacteremia. The theory was that antibiotics would eliminate a local bacteremia that may develop secondary to a dental procedure before it has a chance to spread to the prosthesis. More recently, it has been found that antibiotic prophylaxis (preventative treatment with antibiotics) does not significantly decrease the risk of developing a prosthetic infection in individuals with normally functioning immune systems. Taking antibiotics unnecessarily may also negatively impact the existing bacterial makeup (microbiome) of the body. This is problematic in places like the gut (gastrointestinal system) where an altered microbiome can cause diarrhea, abdominal pain, malabsorption of nutrients and a host of other unwanted symptoms.
Recommendations: Antibiotic Prophylaxis following Total Hip Replacement
In recent years, the American Academy of Orthopedic Surgeons (AAOS) in conjunction with the American Dental Association, has developed a set of recommendations regarding antibiotic prophylaxis prior to dental procedures. The AAOS is the largest group of orthopedic surgeons in the world. They go to great lengths to ensure they present guidelines that accurately reflect the known scientific literature. A summary of the AAOS’ guidelines are as follows:
- Antibiotic prophylaxis is rarely appropriate if an individual is not immunocompromised and has no history of prosthetic infection regardless of whether or not the dental procedure results in agitating the gums (gingiva) and/or other surfaces within the mouth (oral mucosa).
- Antibiotic prophylaxis may be appropriate if the individual has a severely compromised immune system or if they have had a prosthetic joint infection in the past that required surgical intervention.
- Antibiotic prophylaxis is appropriate if the patient has both a severely compromised immune system and has had a prosthetic joint infection requiring surgery in the past.