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VETERINARY
How eating aids the skeletal structure
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HE horse is documented as a prey species and as such retains, despite domestication, areas of hyper-sensitivity in loins, abdominal tunic, and poll; pain experienced in any of these areas, no matter the cause, gives rise to an immediate fright, fight, and/or flight response. Equine dentistry has been practiced since 600 BC and is recorded in varied medical treatises by many of the early masters of equitation, including Xenophon (350 BC), Pliny the Elder (77 AD), and Vegetius (420 AD), who in his Digesta Artis Mulomedicinae appeared to link incorrect chewing methods with poor health. Thus, the art of dentistry is not new although requirement is often ignored as, due to lack of information, the secondary effects of mouth pain are generally underestimated. In order to appreciate this, the basic anatomy of
It has been said that ‘equine conformation evaluates the degree of correctness of a horse’s bone structure, musculature, and its body proportions in relation to each other.’ This is undeniable, but there is remarkably little information in published literature regarding the importance of the position of the head, despite the fact that this has a direct effect on balance, posture, and subsequent performance. WORDS: GaRy WateRS, equine Dental technician, MaRy BROMiley, equine PhySiOtheRaPiSt PhOtOS: GaRy WateRS illuStRatiOn: caROle VinceR
the complexity of the mouth requires consideration. The mouth consists of an upper jaw, or maxilla, an integral unit of the skull; and a lower jaw, or mandible. Muscles and ligaments attach the jaws to the temporal bone or
Caps shed at the same time of year in a large stable
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forehead, an integral part of the skull. The connection of the lower jaw necessitates two joints, one on either side, known as the temporomandibular joints (TMJ). These joints function not only to enable movement of the lower jaw but, through sensors, are involved with balance, and they are also in communication with the bones and joints comprising the poll, which is another important area involved in balance perception/regulation. The mobile tongue is shaped to comfortably cover the upper surface of the lower jaw, its sides in contact with the cheek teeth, the premolars, and molars, which pulverize or grind food. Some of the highly specialist nerves controlling the components of the mouth, unlike most motor nerves, stem directly from the brain and lie, as they track toward the mouth, within the soft tissues of the cheeks. The horse has between 36 and 44 teeth, arranged in equal numbers between the upper and lower jaws. All the incisors and premolars two, three, and four are deciduous (baby teeth), replaced by adult teeth by the age of five. Eruption can be painful and often the shells of the primary teeth are not expelled, remaining jammed and thus a source of pain. A horse is hypsodont, meaning that while