Purpose

The use of odontoplasty for the treatment of malocclusion of incisor teeth in a beaver (Castor canadensis).

Case history

A 3-year-old female beaver (Castor canadensis) was referred to the Veterinary Teaching Hospital of Chungbuk National University. It had been raised in the Cheong-ju zoo and had a history of malocclusion caused by improper feeding. The maxillary and mandibular incisors were maloccluded, as a result of inadequate wear and consequent elongation of the clinical crowns. General anesthesia was induced with 10 mg/kg of ketamine intramuscularly. Once recumbent, preoperative intraoral dental radiographs were taken of the rostal maxillary and mandibular dentition and lateral and ventrodorsal extraoral radiographs of cheek teeth were taken. Radiographs were negative for apical pathology associated with maxillary and mandibular incisors and revealed normal appearance of the occlusions on cheek teeth. The original lesion was likely to be related to the excessive length of the maxillary and mandibular incisors. In order to minimize the duration of anesthesia, the radiographic examination and the surgical procedure were conducted in series. Odontoplasty was performed to reduce overgrowth of the crowns of the incisors using a flat and taper diamond bur (10 mm length) and a water-cooled high-speed hand-piece. Sequential transverse sections were removed until the crown was reduced by approximately its original length. The pulp chamber was never approached during the operation, as confirmed by postoperative intraoral radiographic evaluation of the incisors. Recovery from anesthesia was uneventful and the beaver returned to normal masticatory activities immediately after the operation.

Discussion

Dental procedures are sometimes conducted on exotic animals in less than optimal facilities, and require a flexible approach. The aggressive nature of many exotic animals, including beaver, may delay timely oral health care for logistical and safety reasons. General anesthesia is necessary for thorough oral examination and dental treatment.

References

1.  Clark J.D. et al. 1986. Rodents (Rodentia). In Zoo and Wild Animal Medicine. Philadelphia, W.B. Sauners. 727-724.

2.  Wiggs R.B. et al. 1995. Dentistry in Rabbits and Rodents. In Manual of Small Animal Dentistry. Cheltenham, BSAVA. 67-91.

3.  Wiggs R.B., 1990. Fractured Maxillary Incisors in a Beaver. J Vet Dent. 7, 21,22