ABSTRACT
Equine periodontal disease (ePD) usually starts with food impaction, formation of diastemata, gingival inflammation and formation of periodontal pockets. This process proceeds toward the dentoalveolar space, causing detachment of tooth supporting periodontal fibers. Although several therapeutical procedures have been proposed, ePD is often only diagnosed in advanced stages, requiring dental extraction. A similar dilemma has been observed in small animal medicine, but has been overcome by the introduction of reliable examination protocols for the early diagnosis of periodontal diseases (PD). These protocols are based on detailed anatomical descriptions of healthy gingiva, allowing for the determination of the pathognomonic signs of the onset of PD and providing a basis for grading systems and treatment plans. Consequently, proposals have also been made for periodontal examination protocols in horses. However, these protocols were widely adopted from small animal medicine assuming a similar anatomy of the equine and canine gingiva. To provide a solid anatomical basis for equine specific periodontal examinations, 20 equine heads were examined macroscopically, with special attention to the gingival sulcus, the gingival margin and the interdental papillae. Constant morphological patterns of the gingival margin and the interdental papillae were found for the vestibular and lingual/palatal aspects of the upper and lower cheek teeth arcades, as well as for the incisor arcades. A gingival sulcus measuring greater than 1 mm was present in only 6% of the investigated specimens. The inspection of the gingival margin and the interdental papillae, as well as the recognition of a gingival sulcus, may serve as criteria to establish equine specific periodontal investigation protocols.
ABSTRACT
Equine periodontal disease in horses has long been recognized as a painful disease, leading to a poor condition. The disease is widespread and attracts growing attention in equine dental medicine. The understanding of the underlying etiological and pathological mechanisms of equine periodontal disease is necessary to develop effective prophylactic and treatment options. As a first step, a thorough description of the histological features of the healthy equine gingiva is required. Specimens were taken from six horses (3 mares, 3 geldings, age: 0.5-26 years). The animals were euthanized for reasons not related to this study. Heads were dissected and gingival specimens, including parts of the adjacent teeth, alveolar bone and the periodontal ligament, were obtained from several positions of the dentition. Histological sections were evaluated via light microscopy, with special attention to the structural components of the gingiva, i.e., the gingival sulcus, the epithelium, and the components of the lamina propria (LP). Although the equine gingiva showed the same structural components as described in humans and dogs, the equine junctional epithelium was adapted to the equine dental anatomy and attached to the equine-unique peripheral cementum. Leucocytic infiltrations (LI) of the LP, sulcular epithelium (SE) and junctional epithelium (JE) were frequently seen. The amount of LI was not associated with a macroscopically visual pathology (e.g., diastema or food entrapment) in the respective position. The gingival sulcus depth had an average depth of <1 mm.
