Incisor pathology in wild muskoxen (Ovibos moschatus) from the Canadian Arctic.

Abstract

Dental lesions are often painful and can impair digestive efficiency and fitness in mammals, consequently leading to systemic health complications. Although dental lesions are rarely described in wild herbivores, a high prevalence of incisor abnormalities was detected in wild muskoxen (Ovibos moschatus) using mandibles collected by Inuit hunters through the Community-Based Wildlife Health Surveillance program in the Canadian Arctic. Here, we present the first comprehensive examination of incisor dental lesions and developmental anomalies in wild muskoxen. We examined 243 mandibles from harvested muskoxen and identified and described both gross and radiographic pathology. The most frequent lesion was enamel infractions, characterized by linear cracks along lingual enamel surfaces, which was present in 91.4% (222/243) of individuals. Incisor fractures, which featured at least one incisor with a complicated crown fracture, were present in 50.6% (123/243) of individuals. Labial enamel abrasions were present in 26.3% (64/243) of muskoxen in which wear extended to the dentin, and in severe cases to the pulp. Other common gross abnormalities included rotation (31.3%; 76/243), crowding (21.8%; 53/243), and unerupted fourth incisors (18.9%; 46/243). Radiographic analysis revealed congenitally absent teeth, root fractures, and endodontic-related lesions that correlated with gross incisor abnormalities in a subset of 136 animals. Other radiographic findings included hypercementosis, ankylosis, dilaceration, dental decay, and retained primary teeth. These results underscore the high prevalence and severity of incisor pathology in muskoxen and provide foundational data for subsequent assessment of lesion epidemiology and their association with muskox health.