Introduction

Equine dentistry is the study, care, diagnosis and treatment of pathology in the oral cavity, the maxillofacial area and the adjacent associated anatomical structures, and its impact on the general health and welfare of the equid.

Throughout history, equids have been important for transport, agriculture and military work and early writings have been found about ageing by dentition, and how to perform procedures in the oral cavity.

Some of the procedures described in the literature were painful and even barbaric, especially during the medieval era and beyond in Europe, when oral and dental theories and treatments were based on unscientific myths and superstitions. Examples include; cutting the lips to accommodate the bit, blaming wolf teeth for blindness and mental illness in horses, or the removal of the “lampas” (palatogingivitis that occurs in the rostral portion of the hard palate during the physiological eruption process of central incisors in young animals) by cautery or the use of sharp instruments.

Unfortunately, the latter procedure is still a common practice among breeders, owners and even vets in many parts of the world. In addition to incising the palate and flushing with vinegar in thin older animals, operators are convinced that this inhumane procedure will relieve the animal of malaise of any origin, and will encourage improvements in eating.

The relatively concealed nature of oral and dental disorders and a total lack of knowledge regarding equine dentistry led to the perpetuation of such procedures.

The 18th and 19th centuries in Europe saw extraordinary advances in science that influenced all areas of knowledge and led to important improvements in the field of equine medicine. Diagnoses were now based on logic and evidence. Equine dentistry, however, was not considered a priority in the formal educational practices of that period; in spite of the flourishing new techniques and technology in this field, it was considered more of an art than a science.

In the years following World War II, with the increasing interest in horses for sport and leisure purposes, the hypothetical benefits of dentistry in horses boosted the development of new dental equipment and procedures, although once again without the application of evidence-based scientific research. Indeed, up to the late 1970s there was no real scientific or clinical interest on the part of the academic world or the veterinary faculties in regard to equine dentistry, which was considered to be a minor issue. However, in 1981 the first non-veterinary equine dental schools began to appear in the United States of America, leading the way and giving rise to an increasing number of equine dental technicians practising across the world.

Since then we’ve seen a totally new approach to veterinary dentistry, with equine dentistry following this trend in both veterinary and non-veterinary fields and becoming an increasingly progressive subject. Many high-quality scientific publications have appeared on the subjects of dental embryology, anatomy and the prevalence and aetiopathogenesis of pathology by gross, radiological, histological and ultra-structural examinations. These reflect the tremendous scientific advances in equine dentistry in both clinical and academic fields and among both veterinary and non-veterinary professionals. The dissemination of this knowledge has led to a new global perception of equine dentistry based on the principles of dentistry, medicine and surgery, with some universities and professionals recognising it as a science and as an area of paramount importance regarding equids’ health and welfare. Dentistry is now an integral part of the veterinary curricula of many vet schools.

Nevertheless, the widespread teaching of veterinary dentistry in veterinary schools in many countries is now no more than a distant reality, although the global presence of non-veterinary equine dental schools has remained popular. In either instance, where dentistry is taught there is not always a clear distinction between academic teaching and clinical practice.

From as recently as the start of the 21st century, several dental disciplines, first developed for humans and subsequently used in small animals, have been integrated into equine dentistry, such as orthodontics, endodontics, periodontology and restorative dentistry, in an attempt to preserve functional and health dentition. However, when extrapolating knowledge and effective clinical procedures from other species with brachydont teeth, account must be taken of the unique nature of equids’ teeth, which evolved to be hypsodont (long crowned) as an anatomical adaptation to the high level of attrition associated with their diet and with a unique continuous eruption/wearing process.

The increasing use of ancillary diagnostic tests greatly improves the clinical capacity to achieve accurate diagnosis, particularly when imaging those parts of the head that cannot be properly examined during extra- and intra-oral examinations. Radiography is the most commonly used diagnostic method, especially with the advent of digital systems and the enhancement of radiographic technique for the equid head. Other imaging modalities such as oroscopy, ultrasonography, rhinoscopy, sinoscopy, computed tomography, magnetic resonance imaging and nuclear scintigraphy may be extremely helpful in making a more definitive diagnosis, but much of this technology may only be available in equine referral centres and university hospitals. However, the increasing affordability of equine dental oroscopes has seen a rise in uptake from veterinary and non-veterinary professionals alike.

Although research and clinical work in horse dentistry has progressed substantially in recent years, specific knowledge regarding donkey dentistry is still somewhat behind. This is true in spite of the fact that donkeys
have become popular as companion animals in countries like the United Kingdom and the United States of America, leading to a gradual increase in professional knowledge regarding the health and welfare of the donkey, and that scientific studies focused on donkey dentistry have been promoted by some of the most important charities working with donkeys worldwide.

Recent investigations have demonstrated the similarity between the dental anatomy of the donkey and the horse, the prevalence of donkey dental disorders (through clinical and post-mortem reports) and the potential relationship between dental disease and systemic disorders, which enhances their deleterious effect on donkeys’ health. These studies emphasise the fact that the presence of dental disorders needs to be taken into account when assessing the welfare of donkeys.

The Donkey Sanctuary places dental disease as the second most common veterinary problem encountered in the donkey, after disorders of the feet. Equine dentistry should therefore be considered to be prophylactic, reducing the development of clinically significant pathology and irreversible disease through the early diagnosis and treatment of oral and dental disorders in a conservative way. However, owners should be aware that clinical signs do not always manifest in the early stages and consequently there are a high number of animals suffering from asymptomatic dental and oral disorders – especially donkeys, which are often declared as stoic by nature. It has been shown that regular dental examinations and treatment have a positive effect on long-term dental health and therefore on the general health and welfare of the donkey. The lack of regular examination and preventative treatment in the donkey is therefore a welfare issue, given that even minor problems can in time cause pain and discomfort.

This book is intended as a guide to the anatomical features of the head and oral cavity of the donkey, to offer a greater understanding of the oral and dental disorders that may affect these animals throughout their life, and how to correctly examine, diagnose, prevent and/or treat pathological situations.

The images used in this handbook have been taken from the extensive libraries held by The Donkey Sanctuary and belonging to the contributors to the book.

The contents of this book and additional information are available to download from our website at:

https://www.thedonkeysanctuary.org.uk/what-we-do/for-professionals

The website will be updated as and when new information or research becomes available and you are invited to sign up for news feeds of updates.

Lastly, we have produced a book that we are proud of, with contributions from multiple authors with an in depth knowledge and experience in this field. We hope that this is a valuable reference tool for all those working with donkeys globally.