Left untreated, fractured teeth cause pain, and pain means an animal will avoid using the tooth. In general, treatment options for fractured teeth include removal of the fractured tooth to eliminate the source of pain and infection or root canal therapy with or without placement of a metal crown. Police dogs must have a strong functional "bite" in order to do their jobs correctly. For them a fractured tooth usually gets repaired with root canal therapy and a crown.
Kelly, a police dog that works with Officer Darrin Worsfold at the Galesburg (Ill.) Police Department, recently came to the dentistry service at the University of Illinois Veterinary Teaching Hospital in Urbana with a fractured canine tooth. Officer Worsfold said that before treatment, Kelly wasn't acting like herself. "She was more timid, and she didn't want to fight as much," he recalls.
Dr. Sandra Manfra Marretta, head of the dentistry service at the University of Illinois, treats many police dogs with fractured teeth. She is board certified in small animal surgery and dentistry, and was one of eight founding members of the American Veterinary Dental College in 1988.
She says the most commonly fractured teeth in dogs are the canine teeth, which are used for biting and tearing, and the upper fourth premolar teeth, one of the main teeth used for chewing.
"The purpose of placing a crown on a fractured tooth is to maintain the integrity of the tooth and prevent more fractures," says Dr. Manfra. "Root canal therapy and crown placement is used to preserve the function of the tooth while eliminating the source of pain and infection."
The first step is to perform root canal therapy. The tooth may already be dead if it has been fractured for a long time, or it may be alive and very painful if the fracture is recent. In a root canal, the pulp of the tooth--the innermost portion containing the blood vessels and nerves--is removed, thereby eliminating the source of pain and infection. Once the pulp is removed, the tooth is filled with an inert material called gutta-percha and the fracture site is restored with a white filling.
"The crown is necessary at this point because dead teeth are more brittle than normal teeth," says Dr. Manfra.
Just as in human dentistry, impressions are made to determine not only the shape of the affected tooth, but the shape of the teeth around it. Full mouth impressions and stone models are made to determine how the teeth interdigitate. The models and impressions of the affected tooth are sent to a lab that makes crowns (usually for people). Dog crowns are typically made from titanium, a very strong metal to help prevent further crown fractures. After the metal crown is made, it is cemented in place.
Officer Worsfold was pleased with the results of Kelly's crown. "After the procedure, she was her same old self," he says. While some officers claim that the crown makes their dogs look tougher, Officer Worsfold says he can't tell Kelly has a crown. "Perhaps though, a dog that barks or snarls a lot might show the crown a bit more."
Crowns are not just for police dogs. They are an option for any pet with a dental fracture whose owner does not want to remove the tooth. Even if owners don't choose a crown for their dog, a fractured tooth should always be seen by a veterinarian. The tooth may be painless once the pulp of the tooth dies, but eventually the dead tissue will migrate out the root tip and cause inflammation. This inflammation can spread to the surrounding bone, causing a condition called osteomyelitis. It can cause facial swelling, nasal hemorrhage, and a lot of pain!
For more information about dental problems in dogs, consult your local veterinarian or visit the Web site of the American Veterinary Dental College at www.avdc.org.
Note: An archive of Pet Columns from the University of Illinois College of Veterinary Medicine is available online at www.cvm.uiuc.edu/petcolumns/. Requests for reprints of this article may be directed to Mandy Barth, firstname.lastname@example.org.
Veterinary Extension/Office of Public Engagement University of Illinois College of Veterinary Medicine 217/333-2907