The human mouth contains a great number of very dangerous bacteria. The problem is that these can get into the blood stream with oral infections, or oral when surgery (including teeth cleaning) is performed.

The risk is not limited to resurfacing. Whenever surgery is performed, there is incresased blood flow to the area involved. This occurs for weeks to months while healing of the tissues occurs.

When any kind of bone surgery with implants is performed, new bone growth is stimulated. This contains "neo-vasculature", new blood vessels with are extremely small. If there are circulating bacteria in the blood, they can get stuck in those blood vessels. This can lead to an infection in the bone (osteomyelitis). This is very difficult to treat, and may lead to failure of the prosthesis to bond to the bone. the prosthesis then must be removed, and often can not be easily replaced. Obviously this is nothing to be careless about.

This is uncommon, but I have seen this happen during my career as a radiologist. Diabetics, people on steroids, and others with decreased resistance to infection are at higher risk.

For this reason, surgeons usually give a high dose of antibiotics just prior to all kinds of orthopedic surgery.

The recommendation for pre-dental procedure antibiotics is usually for 1 year after surgery until the blood flow to the post op bone returns to normal. This increased blood flow is easily seen on Nuclear Medicine bone scans. It is also apparent after fractures, with metastatic cancer, and other situation where the bone is undergoing repair.

I therefore strongly recommend that that patients follow the recommendations of their orthopedic surgeons regarding antibiotics post op, especially when undergoing dental procedures. I was very care to take antibiotics pre-dental work for 2 years after my surgery.

Michael (MD in NC) (L) C+ 3/31/03 Dr. Vail

Michael Broder is an MD, Certified by the American Board of Radiology in Diagnostic Radiology, since 1975 and has been practicing in North Carolina since 1976.

Information Statement

Antibiotic Prophylaxis for Bacteremia in Patients with Joint Replacements

This Information Statement was developed as an educational tool based on the opinion of the authors. Readers are encouraged to consider the information presented and reach their own conclusions.

This statement represents the AAOS’ current recommendations on this topic. The AAOS regularly reviews and updates all informational statements as new technology, evidence, or policy is developed. It is possible that these current recommendations may change as the result of the ongoing clinical guidelines development process around the topic of antibiotic prophylaxis for total joint patients undergoing dental procedures. As such, clinicians are encouraged to consider the recommendations in the context of their specific clinical situation and consult, where appropriate, other sources of clinical, scientific, or regulatory information prior to making a treatment decision. Clinicians are encouraged to check the AAOS website for the most up-to-date information.

More than 1,000,000 total joint arthroplasties are performed annually in the United States, of which approximately 7 percent are revision procedures.¹ Deep infections of total joint replacements usually result in failure of the initial operation and the need for extensive revision, treatment and cost. Due to the use of perioperative antibiotic prophylaxis and other technical advances, deep infection occurring in the immediate postoperative period resulting from intraoperative contamination has been markedly reduced in the past 20 years.

Bacteremia from a variety of sources can cause hematogenous seeding of bacteria onto joint implants, both in the early postoperative period and for many years following implantation.² In addition, bacteremia may occur in the course of normal daily life^3-5 and concurrently with dental, urologic and other surgical and medical procedures.⁵ The analogy of late prosthetic joint infections with infective endocarditis is invalid as the anatomy, blood supply, microorganisms and mechanisms of infection are all different.⁶

It is likely that bacteremia associated with acute infection in the oral cavity,^7,8 skin, respiratory, gastrointestinal and urogenital systems and/or other sites can and do cause late implant infection.⁸ Practitioners should maintain a high index of suspicion for any change or unusual signs and symptoms (e.g. pain, swelling, fever, joint warm to touch) in patients with total joint prostheses. Any patient with an acute prosthetic joint infection should be vigorously treated with elimination of the source of the infection and appropriate therapeutic antibiotics.^8,9

Patients with joint replacements who are having invasive procedures or who have other infections are at increased risk of hematogenous seeding of their prosthesis. Antibiotic prophylaxis may be considered, for those patients who have had previous prosthetic joint infections, and for those with other conditions that may predispose the patient to infection (Table 1). ^8,10-16 There is evidence that some immunocompromised patients with total joint replacements may be at higher risk for hematogenous infections.^10-18 However, patients with pins, plates and screws, or other orthopaedic hardware that is not within a synovial joint are not at increased risk for hematogenous seeding by microorganisms.

Given the potential adverse outcomes and cost of treating an infected joint replacement, the AAOS recommends that clinicians consider antibiotic prophylaxis for joint replacement patients with one or more of the following risk factors prior to any invasive procedure that may cause bacteremia.

Table 1. Patients at Potential Increased Risk of Hematogenous Total Joint Infection^8,10-16,18

• All patients with prosthetic joint replacement
• Immunocompromised/immunosuppressed patients
• Inflammatory arthropathies (e.g.: rheumatoid arthritis, systemic lupus erythematosus)
• Drug-induced immunosuppression
• Radiation-induced immunosuppression
• Patients with co-morbidities (e.g.: diabetes, obesity, HIV, smoking)
• Previous prosthetic joint infections
• Malnourishment
• Hemophilia
• HIV infection
• Insulin-dependent (Type 1) diabetes
• Malignancy
• Megaprostheses

Prophylactic antibiotics prior to any procedure that may cause bacteremia are chosen on the basis of its activity against endogenous flora that would likely to be encountered from any secondary other source of bacteremia, its toxicity, and its cost. In order to prevent bacteremia, an appropriate dose of a prophylactic antibiotic should be given prior to the procedure so that an effective tissue concentration is present at the time of instrumentation or incision in order to protect the patient’s prosthetic joint from a bacteremia induced periprosthetic sepsis. Current prophylactic antibiotic recommendations for these different procedures are listed in Table 2. ¹⁹

Occasionally, a patient with a joint prosthesis may present to a given clinician with a recommendation from his/her orthopaedic surgeon that is not consistent with these recommendations. This could be due to lack of familiarity with the recommendations or to special considerations about the patient's medical condition which are not known to either the clinician or orthopaedic surgeon. In this situation, the clinician is encouraged to consult with the orthopaedic surgeon to determine if there are any special considerations that might affect the clinician’s decision on whether or not to pre-medicate, and may wish to share a copy of these recommendations with the physician, if appropriate. After this consultation, the clinician may decide to follow the orthopaedic surgeon’s recommendation, or, if in the clinician’s professional judgment, antibiotic prophylaxis is not indicated, may decide to proceed without antibiotic prophylaxis.

Table 2.

† If a tourniquet is used the entire dose of antibiotic must be infused prior to its inflation

This statement provides recommendations to supplement practitioners in their clinical judgment regarding antibiotic prophylaxis for patients with a joint prosthesis. It is not intended as the standard of care nor as a substitute for clinical judgment as it is impossible to make recommendations for all conceivable clinical situations in which bacteremias may occur. The treating clinician is ultimately responsible for making treatment recommendations for his/her patients based on the clinician’s professional judgment.

Any perceived potential benefit of antibiotic prophylaxis must be weighed against the known risks of antibiotic toxicity, allergy, and development, selection and transmission of microbial resistance. Practitioners must exercise their own clinical judgment in determining whether or not antibiotic prophylaxis is appropriate.

References:

1. Number of Patients, Number of Procedures, Average Patient Age, Average Length of Stay - National Hospital Discharge Survey 1998-2005. Data obtained from: U.S. Department of Health and Human Services; Centers for Disease Control and Prevention; National Center for Health Statistics.
2. Rubin R, Salvati EA, Lewis R: Infected total hip replacement after dental procedures. Oral Surg. 1976;41:13-23.
3. Bender IB, Naidorf IJ, Garvey GJ: Bacterial endocarditis: A consideration for physicians and dentists. J Amer Dent Assoc 1984;109:415-420.
4. Everett ED, Hirschmann JV: Transient bacteremia and endocarditis prophylaxis: A review. Medicine 1977; 56:61-77.
5. Guntheroth WG: How important are dental procedures as a cause of infective endocarditis? Amer J Cardiol 1984;54:797-801.
6. McGowan DA: Dentistry and endocarditis. Br Dent J 1990;169:69.
7. Bartzokas CA, Johnson R, Jane M, Martin MV, Pearce PK, Saw Y: Relation between mouth and haematogenous infections in total joint replacement. BMJ 1994;309:506-508.
8. Ching DW, Gould IM, Rennie JA, Gibson PH: Prevention of late haematogenous infection in major prosthetic joints. J Antimicrob Chemother 1989;23:676-680.
9. Pallasch TJ, Slots J: Antibiotic prophylaxis and the medically compromised patient. Periodontology 2000 1996;10:107-138
10. Rubin R, Salvati EA, Lewis R: Infected total hip replacement after dental procedures. Oral Surg. 1976;41:13-23.
11. Brause BD: Infections associated with prosthetic joints. Clin Rheum Dis 1986;12:523-536.
12. Jacobson JJ, Millard HD, Plezia R, Blankenship JR: Dental treatment and late prosthetic joint infections. Oral Surg Oral Med Oral Pathol 1986; 61:413-417.
13. Johnson DP, Bannister GG: The outcome of infected arthroplasty of the knee. J Bone Joint Surg; 688:289-291.
14. Jacobson JJ, Patel B, Asher G, Wooliscroft JO, Schaberg D: Oral Staphyloccus in elderly subjects with rheumatiod arthritis. J Amer Geriatr Soc 1997;45:1-5.
15. Murray RP, Bourne WH, Fitzgerald RH: Metachronus infection in patients who have had more than one total joint arthroplasty. J Bone Joint Surg 1991;73-A:1469-1474.
16. Poss R, Thornhill TS, Ewald FC, Thomas WH, Batte NJ, Sledge CB: Factors influencing the incidence and outcome of infection following total joint arthroplasty. Clin Orthop 1984;182:117-126.
17. Council on Dental Therapeutics. Management of dental patients with prosthetic joints. J Amer Dent Assoc 1990;121:537-538.
18. Berbari EF, Hanssen AD, Duffy MC, Ilstrup DM, Harmsen WS, Osmon DR: Risk factors for prosthetic joint infection: case-control study. Clin Infectious Dis 1998; 27:1247-1254.
19. Antibiotic Prophylaxis for Surgery. The Medical Letter 2006; 4 (52): 83-88.