The majority of horses examined will have some form of periodontal disease. Periodontal disease is defined as disease of the support structures of the tooth (i.e. the periodontium – the bone of the socket, the periodontal ligament running form tooth to bone, the cementum of the “root” and the gum or gingiva) and can be subdivided into two distinct forms – gingivitis and periodontitis.
 
Gingivitis is a reversible inflammation of the marginal gingiva associated with the presence of bacterial plaque and food particles. If the gingival sulcus (the small gap between the tooth and the gum) is thoroughly cleaned, the gingivitis will resolve. Gingivitis is a precursor to periodontitis. (Figure 1.)

Periodontitis is a more severe inflammation of the supporting structures and usually involves bone loss. It is usually irreversible but potentially controllable. The periodontitis associated with eruption of the teeth will often resolve once the initial eruption is completed.
 
With gingivitis, the marginal gingiva becomes inflamed and oedematous (swollen). This allows bacteria and food particles into the sulcus around the tooth and eventually into the periodontal ligament space. Loss of epithelial attachment occurs and periodontal pockets begin to form. More fermenting food will pack into these pockets and anaerobic bacteria proliferate. This chronic inflammation with associated osteoclast stimulation leads to loss of crestal bone (the interproximal bone between the teeth) and pocket depth increases. (Figure 2.)

In the equine, pocketing of food between teeth in the diastema frequently occurs and fermentation of this impacted food rapidly progresses to periodontitis.

Eventual progression of the disease is such that the tooth becomes mobile and is then lost. A large percentage of horses over 15 years of age will have some degree of periodontitis.
 
The treatment of periodontal disease is based on effective cleaning of the periodontal pockets and prevention of food impaction. This is often extremely difficult in the horse. If a closed-valve diastema occurs, opening this has resulted in resolution of the feed impaction. (Figure 3.)

Good routine dental care from an early age by an experienced equine veterinarian can prevent the development of severe periodontal disease and hence reduce tooth loss in the older horse.

Back