Summary: When finding a malformed tooth structure during oral examination, it is difficult to determine if this abnormality is a dysmorphic tooth or an odontogenic neoplasia. Abnormally shaped teeth and odontogenic neoplasia can have a similar clinical appearance. Conditions that cause disturbances in odontogenesis can lead to abnormally shaped teeth. Odontogenic neoplasia derives from uncontrolledand unlimited growth of dental tissues. Although the clinical symptoms caused by dysmorphic teeth and odontogenic neoplasia might be very similar, these different conditions feature different cellular characteristics regarding the potential risk for further expansion and the prognosis for recrudescence after treatment. For this reason, histopathological examination is required to reach a definitive and correct diagnosis. Odontoma are odontogenic tumours that contain all dental substances with an arrangement that differs from that found in normal teeth. They are further classified as complex-or compound odontoma. Both types are considered to be hamartoma (hyperplastic masses or overgrowth formations of normal tissue) rather than true neoplasia, because of the presence of complete differentiated dental tissues. This case report describes the clinical-, radiological-and histopathological findings that led to the diagnosis of compound odontoma in a 10-year-old gelding with a malformed tooth structure that caused periodontal disease at the position of tooth 202. Treatment included exodontia of the compound odontoma. During surgery, it became clear that the compound odontoma involving retained deciduous incisor 602 had caused fusion by concrescence with the non-erupted permanent incisor 202 -a condition that is hardly ever diagnosed in the horse. The fused teeth were successfully removed using intraoral tooth segmentation, a technique that can facilitate exodontia and reduce the risk of collateral tissue damage.Keywords: fused incisors / compound odontoma / equine dentistry / exodontia / intraoral tooth segmentation