Orthopedic Surgeons and Dental surgeons mention that after having a knee replacement surgery it is important to not have any invasive dental treatments involving surgical procedures performed on the patient for a time period of 8-12 weeks. This is to make sure that no bacteria from the site of surgical procedure travels to the prosthetic knee and leads to infection of the knee. Even after the said time frame it is important for patients who have prosthetic knee implants to mention to their dentists about it, as it is recommended to get Antibiotic Prophylaxis before any dental procedures in patients with knee implants. Dental procedures like Dental Extraction, Dental Implant placement, Flap Surgery, Root canal treatment, etc.
Complications seen in Joint replacement patients is the hematogenous spread of bacteria to the replacement location leading to bacteremia due to tooth extraction. According to latest research, there is no direct spread of bacteria to the joint replacement but it appears to be Transient in nature. The prosthetic joint infection is caused due to chronic infections elsewhere in the body such as UTI, skin infections, pulmonary infections etc. Severe chronic Odontogenic infections are seen to cause prosthetic joint infections in certain patients. 
According to American Academy of Orthopaedic Surgeons, Antibiotic prophylaxis is a must before dental treatments – Amoxicillin, Clindamycin or Cefalexin dose 1 hr before the surgery is recommended. This was based on the statements published in the 2003 and 2009 publications. But according to the December 2012 publication by American Academy of Orthopaedic Surgeons and also a systemic review undertaken by ADA Council on Scientific Affairs undertook a systemic review in 2014 and published in 2014 stating that there was no evidence found of any association between dental procedures and prosthetic joint infections.
Antibiotic Regimen for Prophylaxis of Total Joint Replacement Infection:
Standard Oral Prophylaxis: Cephalosporin or Amoxicillin – 1-2G 1hr before procedure
Penicillin allergic patients: Clindamycin – 600 mg 1hr before procedure
Parentral prophylaxis: Cefazolin – 1 G IV within 1hr of procedure or Ampicillin 600mg IV within 1 hr of procedure
It is being highlighted in the published articles that the negatives outweigh the benefits of undergoing Antibiotic prophylaxis in Prosthetic knee patients, as with repeated Antibiotic medications there are chances of Antibiotic resistant bacteria thriving in the prosthetic regions leading to future complications. So it is better to weigh the Risks vs Benefits and go for the Antibiotic Prophylaxis only after consulting with the Orthopedic surgeon.
In certain cases where Antibiotic medication is a must, it is most appropriate that the orthopedic surgeon recommends the appropriate antibiotic regimen.
References:
- American Dental Association
- American Academy of Orthopedic Surgeons – “Prevention of Orthopaedic Implant Infection in Patients undergoing Dental pocedures”
Dear Dr. Pandula,
What prophylactic antibiotic is reminded for dental cleaning after knee replacement, Thanks.