The prevalence and risk factors of dental disease found in 100 miniature horses

Abstract

Introduction: Dental disease is a common condition affecting horses. Its prevalence and characteristics among most of the common breeds of horses and donkeys have been investigated and described in the literature, but information about the prevalence and etiology of dental disease of miniature horses is sparse.

Methods: To determine the prevalence and characteristics of dental disease of miniature horses, we performed oral and dental radiographic examinations on 100 miniature horses. The findings of these examinations were analyzed to determine the prevalence of dental disease and its correlation to age, sex, weight, body condition score, height at the withers, head length and head width. Older horses had a higher prevalence of dental disease, diastemata and crown elongations.

Results: The most common dental diseases detected in this population were crown elongation, oral mucosal ulceration, diastemata, class 1 malocclusion and hypodontia. Horses with a high body condition score had an increased likelihood of having a class 1 malocclusion. Horses with wider heads had a higher prevalence of dental disease and class 1 malocclusions.

Conclusion: Frequent oral examinations, starting at an early age, should be prioritized as a part of miniature horse preventive health care to decrease morbidity and slow progression of dental disease.

Keywords: dental disease; equine dentistry; hypodontia; miniature horse; prevalence.

Figure 1

Photograph of a 13 years old miniature mare with (A) mesially elongated 206 crown, (B) valve diastema and (C) buccal oral mucosal ulceration adjacent to a 211 mesial crown elongation.

Figure 2

Classification system used for evaluating skeletal and dental malocclusion (11).

Figure 3

The number of horses and the number of teeth affected by the dental disorders identified in this population. Class 4 malocclusion (MAL4), supernumerary tooth (T/SN), fractured tooth (T/FX), unerupted tooth (T/U), dysplastic tooth, persistent deciduous tooth (DT/P), class 3 malocclusion (MAL3), class 2 malocclusion (MAL2), hypodontia, class 1 malocclusion (MAL1), valve diastemata (D/V), oral mucosal ulceration (C/L) and crown elongations (T/EL/CC).

Figure 4

Photograph of a 9 years old miniature mare with axially rotated 402, retained deciduous tooth 803.

Figure 5

(A) LeV60-RtDO and (B) RtV60-LeDO radiographs of an 8.5 years-old miniature horse showing hypodontia of teeth 308, 408 and 411.

Figure 6

A RtD30-LeVO radiograph of a 4.5 years-old miniature horse depicts a retained 608 and absent 208.

Figure 7

Plot of the number of dental abnormalities vs. the age of the animal. As the age of the animal increased the number of dental abnormalities found per animal increased.

Figure 8

Plot of the number of crown elongations per animal vs. the age of the animal. As the age of the animal increased the number of crown elongations identified also increased.

Figure 9

Association of age with diastemata: as the age of the animal increased the likelihood of the presence of diastemata also increased.

Figure 10

Association of body condition score and class 1 malocclusions (MAL1). Horses with higher body condition scores had a higher prevalence of class 1 malocclusion.

Figure 11

Associations with head width: as the width of the horses’ heads increased there was a (A) greater number of class 1 malocclusions and (B) greater number of abnormalities on oral examination.