Document Type : Clinical Report


Department of Clinical Sciences, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran


The development of tooth is a complex process wherein there is a series of interactions between the ectoderm and ectomesenchyme. Hyperdontia (also called supernumerary teeth) is a developmental abnormality being additional to the normal series of teeth with unknown etiology and is rare in ruminants. In this report, a rare case with two abnormal teeth outside the alveolar region, observed in a healthy 3-month-old female lamb was presented. The congenital defect consisted of the presence of 2 teeth positioned bilaterally in the caudal part of the mandible ramus and under the prominent pendulous skin; so, with retraction of prominent pendulous skin, these ectopic teeth were seen outside of the skin. The anomaly was found during a routine physical examination and no other congenital abnormalities were found in the lamb. The etiology of supernumerary teeth is not completely understood. This odontogenic abnormality appears to be an extraordinarily rare condition. Genetic, toxic, infectious or environmental factors related to congenital abnormalities affect the tooth growth. Depending on the supernumerary teeth position, surgery may be required.


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