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The equine cheek tooth battery is part of a very dynamic system. The aim of this study was to investigate whether the curvature and position of the teeth are also involved in such dynamical processes. The alveolar crest was labelled with a radiodense marker (48 cadaver heads, 15 skulls) and laterolateral radiographs were taken. Then a geometrical method was elaborated to determine a cheek tooth's curvature and its position by means of specific angles. This method respects the remarkable changes of the equine dentition throughout life by considering two items: (1) the alveolar crest was taken as a constant landmark, (2) the central axis of the curved dental crown was determined by calculation of a linear regression equation. This equation considered several geometrically determined points on the curved dental crown which had been marked in the radiographs. Our study yielded the following results: Mandibular cheek teeth became more curved with age, but their positions (represented by the so-called mesio-occlusal angle between tooth and alveolar crest) did not change significantly. In maxillary cheek teeth, however, the mesio-occlusal angle became larger with age (indication of change of dental position), while their curvature did not change. Even though changes of the dental position were not always statistically significant, they are discussed as being biologically/functionally relevant. The mandibular anticlinal tooth, i.e. the tooth positioned at a mesio-occlusal angle of about 908, was not in contact with the maxillary anticlinal tooth. Interestingly, the maxillary anticlinal tooth is known to cause most clinical dental problems.

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The Curve of Spee is well known, yet hardly understood in the horse, as there is a striking lack of biometrically related data which could help to explain its biomechanical significance. Older horses display drastic alterations of the Curve of Spee in routine clinical examinations. Since the Curve of Spee is known to be biomechanically related to the masticatory forces in humans, the same may apply to the equine, and masticatory deficits can be expected in the geriatric horse. Quantitative data of the Curve of Spee cannot be obtained directly by means of measurements in the horse's long and narrow oral cavity. Instead, the radiographs of 24 heads and 6 skulls of horses of different age were used to develop a geometrical procedure facilitating a quantitative analysis of the height of the Curve of Spee. The geometrical values gave clear evidence that the height of the Curve of Spee was smaller in groups of older horses compared with those of younger horses. This finding was in accordance with biomechanical studies which reported decreased masticatory forces in older horses.

A multitude of ocular diseases can lead to a loss of vision and permanent ocular pain in horses.The present paper addresses the topic of cosmetic and reconstructive surgery in equine ophthalmological patients based on the implantation of intrascleral silicone prostheses. Thirteen horses aged between four and twenty years with various ocular problems requiring removal of a blind and/or painful eye were placed under general anaesthesia. After evisceration of the globe, a silicone prosthesis was introduced into the sclera. Sclera and conjunctiva were sutured and the horses were treated with NSAIDs and ophthalmic ointments postoperatively. After healing of the surgical wound, a dark tinted bandage lens could be placed over the eye by the owner to further enhance the cosmetic result. The surgical wounds healed well in all horses. One horse had a deep corneal ulceration and the prosthesis had to be removed two weeks after surgery. Two horses developed eosinophilic keratitis six and eight weeks after surgery, respectively. The condition was repeatedly treated with a diode laser and ophthalmic ointments and resolved subsequently. One horse showed transient swelling in the surroundings of the eye that resolved within two days. The corneas of the eyes that underwent surgery passed through various stages of cloudiness and vascularization, as well as epithelial reconstruction, followed by pigmentation. Intrascleral silicone prostheses in combination with a dark tinted bandage lens yield a cosmetically excellent result that is well received by the owners. It serves as a cosmetically superior alternative to plain enucleation or enucleation and subsequent placement of an intraorbital prosthesis in cases where the removal of a blind and/or painful eye is inevitable.