Dental and temporomandibular joint pathology of the red fox (Vulpes vulpes)

Abstract

Skulls from 305 red foxes (Vulpes vulpes) were examined using predefined criteria to assess for the presence and severity of dental and temporomandibular joint (TMJ) pathology. Of the 305 specimens examined, 131 were male (42.9%), 103 were female (33.4%), 71 were of unknown sex (23.3%), 238 were adults (78.03%) and 67 were young adults (21.97%), with juveniles excluded from the study. Of a maximum of 12,810 possible teeth, 12,355 (96.5%) were present for examination, 72 (0.6%) were absent congenitally, 97 (0.8%) were acquired tooth loss and 280 (2.2%) were absent artefactually. Eight teeth (0.06%) in five specimens (1.6%) had abnormal tooth form and four (0.03%) supernumerary teeth were present across four (1.3%) specimens. Ten persistent deciduous teeth were present in seven (2.3%) specimens and six (0.05%) unerupted teeth were found in four (1.1%) specimens. Root number variation was present in 51 (0.4%) teeth, predominantly premolar teeth. Twenty-one (6.9%) specimens had lesions consistent with enamel hypoplasia and 42 (13.8%) showed root fenestrations in the maxillary alveolar bone. Periodontitis and attrition/abrasion were present in most specimens (56.7% and 96.1%, respectively). Three-hundred and eighty (3.1%) teeth were fractured, with the most common fracture type being root fractures. Eleven periapical lesions were found in nine (0.03%) specimens. Six-hundred and eight TMJs were evaluated and many specimens (11.5%) had evidence of low-grade TMJ osteoarthritis. Overall, these red foxes share similar dental pathology to other foxes, but had a higher prevalence of congenital tooth absence, persistent deciduous teeth, TMJ pathology and enamel hypoplasia.