Dental fractures are a common problem in veterinary medicine. Both dogs and cats experience these fractures at a rate of 10% to 20% of all pets. Dogs, however, not only seem likelier to sustain these types of injuries, they're also susceptible to a wider variety of dental fractures than their feline counterparts.
Fractures are often roughly classified as either complicated or uncomplicated. Due to their typical differences in cause, diagnosis and treatment, there is a separate article for complicated fractures.
For dogs, the most often affected teeth include the two maxillary canine teeth (their "fangs") and the maxillary fourth premolars (the two largest teeth) which are located on both sides of the upper jaw. The canines of the lower jaw (mandlible) and the mandibular incisors (smallest teeth) are next most likely to suffer uncomplicated fractures.
Meanwhile, cats most often suffer fractures to their canine teeth. As in dogs, the maxillary canines are more susceptible to fracture than the mandibular canines.
While trauma is the most common cause of uncomplicated dental fractures, abrasion of the teeth (as when chewing hard objects over a long period of time) and attrition (defined as abrasion that occurs with tooth on tooth contact), are also possible causes. The mandibular incisors are more commonly affected than most other teeth. If this damage is severe, complicated fractures may also ensue.
Uncomplicated dental fracture types include the following:
Enamel infraction (incomplete crack in the enamel)
Enamel fracture (a fracture in the enamel that extends into the substance of the crown)
Uncomplicated crown fracture (a fracture of the crown that doesn't extend into the tooth's interior, known as the pulp)
Uncomplicated crown-root fracture (a fracture that extends beneath the gumline but doesn't expose the pulp and leaves at least 2mm of attached gum)
If the trauma is superficial, as with enamel fractures or uncomplicated crown fractures, the tooth may simply become more susceptible to severe fractures. In a minority of cases, however, the dentin exposed after sustaining these minor fractures can predispose the tooth to infection, death (necrosis) of the nerve and vessel contained within its pulp cavity. This can lead to infection and abscess of the tooth's root.
Symptoms and Identification
The clinical signs of dental fractures are not always as obvious as pet owners might suppose. Indeed, most dogs and cats don't display any outward signs of discomfort. In large part, that's because most uncomplicated fractures are not painful. That is, unless the pulp becomes infected or the fracture extends beneath the gumline. Most of these pets manage to avoid detection either by chewing with the other side of their mouths or by swallowing their food whole.
Owners who brush their pets' teeth or are otherwise able to explore their pets' mouths may observe one or more of the following signs:
A missing piece of a tooth (owners are encouraged to compare it to the same tooth on the opposite side of the mouth)
Discoloration of part or all of a tooth
A visible crack on the surface of the tooth's crown
Diagnosis of uncomplicated dental fractures is generally achieved by simple observation. However, dental X-rays may be required in some cases to ensure the integrity of the affected tooth's root.
Dogs and cats whose dental fractures have led to a tooth root abscess may notice swelling on the side of the face and sometimes even open, oozing sores on the face (most commonly under the eye).
All breeds of dogs and cats can suffer uncomplicated dental fractures. Some breeds, however, may be predisposed to certain kinds of fractures due to their conformation.
Treatment of uncomplicated dental fractures depends on their type:
Enamel infractions: These don't progress and, therefore, don't require treatment.
Enamel fractures: Smoothing the edges of these fractures is generally considered sufficient treatment. Some, however, require restoration (by overlaying it with a liquid material that hardens into a tooth-like texture).
Uncomplicated crown fractures: Young patients require crown restoration and frequent X-rays as follow-up. Older patients require no treatment unless the fracture is close to the pulp, in which case a metal crown might be indicated.
Uncomplicated crown-root fractures: Removal of the unattached gum and restoration are generally considered necessary.
The cost of dental fractures varies depending on the kind of fracture and the elected level of treatment. Because many uncomplicated fractures are left untreated, the expense of their treatment tends to be minimal.
If restoration is elected, as is recommended with most, expenses generally come in at $300 to $500. Board-certified veterinary dentists, however, may charge more for this procedure.
Prevention of dental fractures requires that owners employ effective trauma prevention tactics. Safety when it comes to access to balconies and other high places (especially for cats) and vehicles is a must, of course, but also is the use of appropriate chews and toys and watchful access to the outdoors if rock-chewing behavior is a factor.
For crated pets, care should be taken to avoid certain crate or cage varieties if dogs take to chewing the bars. (This is especially common in anxious dogs, as during thunderstorms.)
Rubbery, plastic toys are generally considered safe. Cow hooves, antlers and cooked bones are considered potentially problematic and should be avoided.
Trainers and handlers of working dogs should avoid the use of hard training devices and remain vigilant for signs of fractures so as to seek the earliest treatment possible.
American Veterinary Dental College. Veterinary Dental Nomenclature. Dental Fracture Classification. Available at http://www.avdc.org/. Accessed April 30,2008.
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