A five-year, nine-month-old Canadian beaver was presented for treatment of lip trauma resulting from overgrowth of the mandibular right incisor following earlier loss of the right maxillary incisor. Extraction of the affected tooth was considered but rejected due to the length of the embedded portion of rodent mandibular incisor teeth. The lip injury was managed by regular crown reduction of the overgrowing incisor every eight weeks, whilst a more permanent solution to the problem was planned. An apicoectomy of the caudal 2 cm was performed on the right mandibular incisor to arrest growth of the tooth. It took the remainder of the tooth nine months to erupt to the level where it was expelled from the body, further coronal reduction being required once during this period. Radiographic follow up, nine-months post expulsion, confirmed complete tooth loss and the alveolus filled with radio dense tissue. This tissue has the same density as bone.

The growth of the resected tooth slowed down, contrary to experimental cases done on rats. A further complication of the premature loss of the maxillary incisor was the medial deviation that occurred on the left maxillary incisor. Once the right mandibular incisor was removed the left maxillary incisor started to wear on the lateral aspect. Corrective trimming of both incisors are envisaged for the future.