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Introduction

The purpose of this book is to educate the reader as to the essence of therapeutic modalities and pitfalls when performing dentistry on captive animals in sanctuaries, zoos or in the field. To cover every aspect of dentistry, or every species encountered, is beyond the scope of this book. We have included the most frequent species and dental pathologies that clinicians will see and be asked to treat. We hope this work will expand wildlife animal dental knowledge, resulting in increased success of dental procedures in the field.

It should be emphasized that dentistry and oral surgery is similar to other veterinary disciplines in that success of a clinician is dependent on knowledge, expertise, equipment, and patient compliance. The same ingredients make a good dentist as do a good surgeon, and the treatment for a number of oral conditions involve surgery. There are unique endodontic morphologies present in various species, especially large felids, that make it essential that the practitioner obtain hands‐on tutoring before attempting endodontic therapy for large felids. One should be well rested, well prepared, well equipped and well skilled, especially before attempting to treat wild animals in zoological or sanctuary settings, where often, because of anesthetic risk, there will be only one opportunity to perform therapy. Well rested is self‐explanatory. An alert, aware and energetic individual is one who can provide a smoothly executed procedure. A well‐prepared individual is one who knows the protocol and instrumentation of planned procedures, as well as that of alternative procedures that might be required. Skill comes with experience, and experience comes with practice. Additionally, the well‐prepared clinician will be well equipped. Using the appropriate instruments, well maintained, will help to lessen procedure time, minimize patient discomfort and reassure the clinician that they have performed a proper procedure in the best way possible.

Through the skill of veterinary dentists, enhanced comfort can be achieved for these animals who cannot help themselves, and improved longevity can be realized by the reduction of chronic oral pain and stress experienced by these animals who are less often treated.

Increased knowledge of the species‐specific anatomy, physiology and oral function will be invaluable in achieving proper diagnosis and treatment. This does not reduce the importance of hands‐on experience, as each case and each animal is unique. For example, the vast majority of tiger upper canines have a bulbous apical root canal morphology with an extended apical delta at the root end terminus. Thus, treatment for each species will be different, and will require adaptation in the field.

Wildlife dentistry is infrequently encountered in veterinary practice. The diverse dental findings as to endodontic morphology, occlusal, and radicular forms, tooth sizes, and numbers of teeth all complicate exotic animal dentistry. Difficulty in obtaining routine oral examination to intercept developing problems and provide routine dental maintenance is a large factor in maintaining or regaining oral health. Additionally, poor financial rewards, lack of exotic animal dental knowledge and education, all contribute to the challenges of providing successful oral care for these animals.

All the dental disciplines practiced in human and small animal dentistry can be practiced in exotic animal or zoo dentistry. However, the many dental morphological and pathological differences seen in the various species create treatment challenges that can extend far beyond routine procedures. Dental problems can be multiple, complex, and often unseen in domestic small animal dentistry. Therapy can be complicated by limited oral access in some species. Most zookeepers are untrained in recognition of developing dental problems. This results in advanced dental pathology before the condition becomes clinically evident. Because of advanced levels of pathology, therapy is often more difficult and with uncertain prognosis for success.

Zoo dentistry includes many and varied species. New technologies are now beginning to be seen, or at least contemplated, in the treatment of some of the large species. If we consider, for example, that an elephant tusk is an upper lateral incisor, with pulp tissue and an open apex, then we can pursue the possibility of endodontic therapy for affected tusks rather than the very difficult procedure of tusk extraction.

Avian species primarily present with lost or fractured beak segments or beak malocclusion resulting from poor nutrition. Replacement of lost beak segments can be performed with dental acrylic, threaded pins, ligature wire and cyanoacrylate. Congenital or traumatic malocclusion or “cross beak” is not uncommon, especially in psittacine birds. Active rubber orthodontic ligatures and threaded pin anchors can sometimes effectively correct this form of malocclusion. Like birds, the most common dental problem seen in reptiles is oral trauma, and the same principles of repair as employed in avian dentistry can be utilized. For example, turtles, can present with “beak” fracture. Dental acrylics, threaded wire, and cyanoacrylate can rehabilitate these animals. Though not a dental procedure, the repair of fractured turtle shells with dental materials is also a commonly successful and practical procedure.

An excellent example of advanced pathology with limited therapy and success is seen in mandibular and maxillary abscesses in herbivores and ruminants. Their dentition is primarily selenodont, which has parallel rows of crescent‐shaped occlusal ridges that run in a mesial to distal direction. Selenodont dentition is the principal dental form in the order Artiodactyla, which includes most sheep, cattle, antelope, deer, camels, boars, and hogs. However, the animals most affected with mandibular/maxillary abscesses are the Marsupialia, primarily kangaroos and wallabies. Their molar form is a rather primitive tribosphenic form – that is, having three basic cusps. They are the protocone (the lingual cusp of the upper molar – it is generally narrow), the metacone (the posterior buccal cusp), and the paracone (the anterior buccal cusp). There are accessory cusps on metacone and paracone, termed metaconule and paraconule. These accessory cusps, such as the metaconule, are very important in Artiodactyle masticatory function.

The principal dental morphological difference between marsupials and placental species is the relative shape of the external part of the molar. The other dental form found in common herbivores is lophodont dentition. Lophodont dentition has parallel ridges that course across the entire coronal width from lateral to medial. Lophodont dentition is found in the order Perrisodactyla, as well as the families Tapiridae and Rhinocerotidae (the tapir and the rhinoceros).

It is impractical, though possible, to develop successful techniques for orthodontics, restoratives, crown coverage, and possibly bridge procedures in wildlife dentistry, but many oncology cases present unique therapeutic challenges that can be managed with diagnostic and therapeutic help of oncology specialists.

Periodontal Disease

Most forms of periodontal disease seen in domestic animals can be found in exotic animals, with treatment similar to that performed in humans. Primates display periodontal disease very similar to humans. Extensive periodontitis with advanced tooth‐supporting bone loss can also be severe in non‐primates, especially so in orangutans, where it is accompanied with the usual symptoms of bacterial infection and general malaise. Periodontal therapy is diverse, ranging from simple prophylaxis to advanced surgical gingival flap procedures with bone augmentation, lateral sliding flaps, and advanced procedures that also include surgical exodontia. Cases of gingival hyperplasia can be treated with either electro‐surgery or sharp dissection.

Many of the anatomical peculiarities and proposed treatments in this book may not be found elsewhere in print, as they are the result of an accumulation of 50 years of personal hands‐on treatment and personal experience while working on thousands of animals among hundreds of species. We still have much to learn, and with dedication we will continue to improve our ability to help the many species that cannot help themselves as we provide better oral health, comfort and increased longevity in animals worldwide. This book provides a foundation of information. We hope that future contributors will add to this information in an ever‐expanding source of information that will serve to help improve and maintain improved oral health in the many species of animals throughout the world.

Finally, due to the constraints of length within the Table of Contents, it has not been possible to list the most common (but not inexhaustible) 352 species found in animal sanctuaries and zoos throughout the world. However, these are listed in the index and should be easily identifiable, helping all readers to identify the myriad of animals they may be called upon to examine and treat.

Peter P. Emily, DDS, Certification Periodontics, Endodontics, and Oral Surgery, Hon. Diplomate American Veterinary Dental College