Equine Dentistry: Toward Non-Routine, Tailored Antibiotic Therapy

In equine dentistry, the administration of antibiotics has become a “comfort measure.” They are prescribed, in particular, in the context of a tooth extraction, sometimes with no justification other than the precautionary principle: the idea is to prevent an infection, avoid a rare complication, and reassure the owner. A review published this month reminds us that caution is not a treatment, and habit is not evidence. This publication puts therapeutic decision-making back on the right track—that is, based on a risk-benefit analysis where the benefit must be real and the risk must be assessed.  

What the Literature Says (and Doesn’t Say) About Prophylaxis

While infectious complications do occur following tooth extraction in horses, they are not common. Most importantly, the available studies do not show a significant reduction in side effects with routine perioperative antibiotic therapy. In several studies cited in the article, complication rates remain similar, with or without antibiotics. More troublingly, some authors report a link between antibiotic therapy and complications. This does not mean that the antibiotic is to blame, but rather that it is used more readily when the extraction is complex, traumatic, or already complicated. Thus, if we wish to reduce complications, the primary focus should be on surgical technique, aseptic technique, and case selection.  

The Risk of Endocarditis in Horses

Another common justification for antibiotic therapy is the fear of transient bacteremia associated with dental care and infectious endocarditis. Here again, the review puts things into perspective. While transient bacteremia can occur after a tooth extraction, the link between bacteremia and endocarditis has not been established in horses; therefore, this is an extrapolation from human dentistry or that of pets.  

Significant Side Effects

The publication also points out that antibiotics are not harmless. In horses, these drugs can promote imbalances in the gut microbiota, reduce the diversity of the bacterial flora, and, of course, increase selection pressure on resistant bacteria. The risk is very real. Dentistry involves an area rich in biofilms, where the exchange of resistance genes within the bacterial community is a biologically established fact. Added to this is the risk of digestive disorders (diarrhea) associated with antibiotics, which can sometimes be severe in equines.  

Different Recommendations Depending on the Condition

The journal does not advocate for dental practice without the use of antibiotic therapy, but urges responsible use of antibiotics and recommends reserving them for high-risk situations. The authors identify the contexts in which antibiotic therapy may be justified: in cases of fever or systemic disease, immunosuppression, significant oral trauma, suspected tissue spread, osteomyelitis, severe apical infection with complications, or sinus surgery, for example. In these cases, antibiotics are essential. However, antibiotic therapy is not a substitute for dental care and is not indicated as part of endodontic treatment in the absence of infection. Regarding periodontal disease, the publication notes that the cause is often mechanical (diastema, malocclusion, food impaction) and inflammatory, sustained by biofilm. The effectiveness of antibiotics is limited in the oral cavity (due to saliva, food, dilution, and protective biofilm). Management primarily involves correcting the underlying cause and local treatment. For dental fractures, the outcome again depends on the treatment implemented (extraction or endodontic procedure), not on empirical antibiotic therapy. The true indications involve open traumatic fractures of the mandible, where the risk of infection is high. For equine odontoclastic tooth resorption and hypercementosis (EOTRH), antibiotics have no effect on the course of the disease. The treatment of choice is extraction of the affected incisors, along with an appropriate analgesic regimen. For dental sinusitis, the same logic applies: management depends on the diagnosis, extraction of the causative tooth, and restoration of drainage. Antibiotics may help in certain situations, but they are not the cornerstone of treatment. In conclusion, it is no longer a matter of routinely resorting to antibiotics, but of asking the question: “What, in this specific case, makes antibiotic therapy necessary?” This is why equine dentistry remains a medical procedure that requires clinical decision-making (treatment strategy, choice of drug, dosage, duration, etc.).