Rostroversion of the maxillary canine tooth
Rostroversion of the maxillary canine tooth, also called the lance tooth, is an orthodontic problem encountered most commonly in Shetland sheepdogs. A common method of correction involves using
a cheek elastic fixed to orthodontic buttons that have been cemented in specific places on selected teeth. Success depends
on the ability to supply sufficient anchorage in the caudal part of the dentition to accomplish movement of the large-rooted
canine tooth. To achieve sufficient anchorage, the carnassial tooth (maxillary fourth premolar) and the maxillary first molar
must be stabilized together (Figures 6A & 6B).
Figure 6A. Orthodontic correction of rostroversion of the maxillary canine tooth in a Shetland sheepdog. Note the malposition
of the lance tooth (arrow). Orthodontic buttons have been cemented to the maxillary canine tooth, the maxillary fourth premolar,
and the maxillary first molar (under the composite). An elastic power chain is attached to these buttons and is being used
to create a caudal tipping force on the malpositioned canine tooth. Composite bonding has been used to stabilize the maxillary
fourth premolar and the maxillary first molar together to provide sufficient anchorage. 6B. Three weeks into therapy, the
canine tooth (same tooth as in 6A) has moved into an almost normal position.
The critical steps in dealing with orthodontic problems in dogs include properly diagnosing the problem, determining the most
appropriate method to achieve the goal of a healthy and comfortable occlusion, counseling owners about breeding and future
showing potential, and selecting the proper orthodontic treatment technique. Clients need to be taught how to provide good
oral hygiene and must commit to frequent follow-up visits during the treatment. Some therapies such as deciduous tooth extraction
and rubber ball therapy can easily be incorporated into general veterinary practice. The more advanced techniques involving
appliance fabrication and application are best referred to a veterinary dental specialist. A list of veterinary dental specialists
is available at
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2. Changes in appearance by artificial means that require disqualification of a dog from shows and obedience trials. Special
AKC Bulletin; Reprinted from Pure-Bred Dogs/American Kennel Gazette, November 1989.
3. Verhaert L. A removable orthodontic device for the treatment of lingually displaced mandibular canine teeth in young dogs.
J Vet Dent 1999;16:69-75.
4. Surgeon TW. Fundamentals of small animal orthodontics. Vet Clin North Am Small Anim Pract 2005;35:869-889.
1. Bellows J. Small animal dental equipment, materials and techniques. In: Oral surgical equipment, material, and techniques. Ames, Iowa: Blackwell, 2004;297-321.
2. Harvey CE, Emily PP. Small animal dentistry. St. Louis, Mo: Mosby, 1993.
3. Holmstrom SE, Frost P, Eisner ER. Exodontics. In: Veterinary dental techniques for the small animal practitioner. 2nd ed. Philadelphia, Pa: WB Saunders Co, 1998;215-254.
4. Shipp AD, Fahrenkrug P. Practitioner's guide to veterinary dentistry. Beverly Hills, Calif: Dr. Shipp's Laboratories, 1992.
5. Wiggs RB, Lobprise HB. Clinical oral pathology. In: Wiggs RB, Lobprise HB, eds. Veterinary dentistry principles and practice. Philadelphia, Pa: Lippincott-Raven, 1997.
The information and photographs for "Dental Corner" were provided by Daniel T. Carmichael, DVM, DAVDC, Veterinary Medical
Center, 75 Sunrise Highway, West Islip, NY 11795.
Dr. Daniel T. Carmichael