In contrast to the cheek teeth dentition the equine incisor dentition is composed of very similar teeth in the upper and lower jaw regarding the morphology of the occlusal surface, which can best be described as follows. Each equine incisor features a peripheral enamel ring without any foldings. The peripheral enamel ring is supplemented by one inner enamel ring in the center of the occlusal surface. This inner enamel ring represents the occlusal aspect of a cone-shaped infundibulum, also known as “cup”. The area in between the peripheral enamel ring and the infundibular enamel consists of occlusally exposed dentine. Due to the lower resistance of the dentine, the dentine area becomes more abraded than the enamel rings during mastication, resulting in a relief of tangibly higher enamel rings and a dentine basin. Remarkably, the colour of the dentine is not uniformly beige, but shows dark brown areas labial to the infundibulum. These brownish areas are colloquially called “dental stars”. In fact, these areas indicate the position of pulp cavities some millimeters underneath the well mineralised occlusal surface and should therefore be labelled as pulp positions - just like on the occlusal surfaces of cheek teeth. Structurally, the brown-coloured dentin areas are composed of a special type of secondary dentin (irregular secondary dentine), which is formed by pulpal cells in response to mechanical abrasion on the occlusal surface and thus prevents the occlusal exposure of pulp tissue.

Similar to the cheek teeth, the incisors are surrounded peripherally by a layer of dental cementum. However, in contrast to the molars, the peripheral cementum is quite thin and splinters off over a large area, especially labially, so that a mosaic of porcelain-coloured enamel surfaces and brownish cementum residues is always perceived when viewing the incisor dentition from the rostral aspect. Similar to the cheek teeth, equine incisors constantly experience massive occlusal abrasion of 2 mm per year and even more. This loss of substance is compensated for by a continued eruption of the tooth. However, these processes are not accompanied by a continuous reduction in the length of the incisors, as is the case in the cheek teeth dentition. Up to a tooth age of 13-15 years post eruption, equine incisors can compensate for the occlusal loss of substance by apical lengthening of the tooth. Only after this period of time do equine incisors become steadily shorter. Another significant difference between equine incisors and molars lies in the principles of their anatomical design. Cheek teeth have a very homogeneous structure along their longitudinal axis, so that the morphology of the occlusal surface does not change over a long period of time, although there is constant tooth wear. In contrast, the incisors have a construction plan that results in a constantly changing pattern of the occlusal surface with every millimeter of wear on the occlusal surface. Accordingly, a rough age estimate can be made on the occlusal surfaces of the incisors, but not on the equine cheek teeth.

The listed peculiarities of the equine incisors are not only interesting from an anatomical perspective, but also offer aetiopathological explanations for clinically relevant diseases such as EOTRH.