Potential impact of natural conditions on the rostral oral health: a study of horses in Iceland.

OBJECTIVE: In the context of a study of Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH), elderly Icelandic horses were examined in their originating country. The subject of this survey was the impact of dental treatment and keeping and feeding management on the health of the rostral oral cavity. ANIMALS: A total of 170 horses (aged ≥ 15) located in different areas of Northwest, West, and South Iceland. METHODS: The horse owners completed a questionnaire about keeping, feeding, and preventative dental care. The horses were clinically examined with particular attention to gingival and dental disorders of the rostral mouth, such as gingivitis, fistula, gingiva retraction, enlargement of the roots and dental calculus as well as integrity of incisors, bite angle, and tooth mobility. RESULTS: Most of the horses were kept on pasture all year with little supplementary feeding. The frequency of dental treatment in Iceland was low. Only a few horses were affected by tooth loss, gingivitis, gingival recession, and incisor calculus. Calculus occurred more frequently and more severely in canines than in incisors. The findings did not depend on the location of the horse. CLINICAL RELEVANCE: Assuming that the remarkable health of the rostral oral cavity in elderly Icelandic horses was not caused by preventive dental care, it is likely that it was due to living conditions in Iceland. Continuity, intensity of chewing, and nativeness of forage might promote the health of incisors and tissue surrounding the tooth even in elderly horses.

Widespread prevalence of Equine Odontoclastic Tooth Resorption and Hypercementosis detected in German Icelandic horse population: impact of anamnestic factors on etiology.

OBJECTIVE: To compare anamnestic factors in Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH) in affected and nonaffected horses to detect risk factors for horses developing EOTRH. ANIMALS: A total of 154 Icelandic horses, aged 15 years and older, examined at 22 locations in Lower Saxony, Germany. The investigations took place from October 2020 to December 2021. METHODS: Anamnestic data were collected using an owner-completed questionnaire. Horses underwent a thorough physical examination and CBC. The rostral oral cavity was clinically examined, and intraoral radiographs of the incisors were taken. Clinical and radiographic findings were scored. Based on the results, the study population was separated into "EOTRH-affected" and "EOTRH-healthy" horses. Both groups were compared to identify differences within the anamnestic factors. In case of inconclusive findings, some horses were classified as "suspicious". RESULTS: The diagnosis of EOTRH was made in 72.2% (109/151) of horses. The risk of contracting the disease increased with the age of the horse (P = .004). In addition, there was a predisposition for male animals (P = .032). Feeding, keeping, and dental treatments showed no significant influence, while place of birth seemed to influence horses developing EOTRH (P = .017). CLINICAL RELEVANCE: The results highlight how widespread EOTRH is among the German Icelandic horse population and the need for raising awareness of EOTRH, as many horses were not suspected of having EOTRH beforehand. Moreover, numerous etiological propositions exist, but, to date, no studies have investigated their relevance.