[Dental care and joint prostheses]

Infectious dental foci and oral dental care constitute one of the leading causes of arthroplasty infection after infections involving the skin and the urinary tract. There is however no formal evidence confirming the relationship between oral or dental care and arthroplasty infection.

We reviewed 44 cases of arthroplasty infection secondary to dental infections and searched for data in the literature. In our series, no risk factor could be identified for 24 cases. The median disease-free interval was five years and mean time from the oral-dental procedure to the first signs of prosthesis infection was one month. Tooth extraction was the most common oral-dental procedure involved (n=19). Most of the infections were caused by a single agent, predominantly Streptococci sp. (n=24) and Staphylococci sp. (n=12).

It is well known that dental-related bacteriemia is a spontaneous daily event even without dental procedures. It is also probable that spontaneous bacteriemia induced by daily activities is much more frequent than dental-care induced bacteriemia. The presence of foreign material diminishes local antibacterial defense systems increasing the risk of hematogeneous contamination of the joint prosthesis after dental care. The oral flora is also modified in immunodepressed subjects, particularly carriage of Staphylococcus aureus in the oral cavity which is significantly more frequent in patients with rheumatoid arthritis. These changes increase the risk of contamination after dental care. For arthroplasty infection, the pathogenic power of Staphylococci sp. is certainly greater than that of Streptococci sp. even if the inoculum is less abundant. Antibiotic prophylaxis during dental care in patients with an arthroplasty remains a controversial subject and the most appropriate antibiotic remains to be defined. Successive episodes of spontaneous bacteriemia arising from an oral-dental foci are probably the main cause of arthroplasty infections, more so than bacteriemia triggered by dental care.

Antibiotic therapy is not indicated for routine dental care in the majority of patients but is recommended whenever there is a high risk of arthroplasty contamination. In the event of oral-dental infection, antibiotic therapy is necessary. The recommendations proposed by the ADA and the AAOS were revised in 2003. The most important point is to obtain and maintain a good state of oral hygiene. For prevention, awareness of the risk is essential, for the patient, the orthopedic surgeon and the primary care physician alike. Regular dental visits are necessary.