IS THAT TOOTH FRACTURED?
TIPS FOR DIAGNOSING AND OPTIONS FOR TREATING THIS COMMON INJURY
By Michael Jennings, VMD, DAVDC
Board-Certified Dentist & Oral Surgeon
We all recognize the fractured tooth that presents to our office: the puppy coming in with a bleeding canine tooth or slab fracture after chewing on a bone, or the older animal that presents with the classic swelling under its eye, indicating a likely tooth root abscess. But did you know that over 25% of dogs and cats visiting the vet for unrelated reasons have been reported to have one or more fractured teeth? Or that over 10% of those fractures involve the pulp1? Many of our dogs and cats are living with injuries that are causing an underlying degree of pain and infection. This pain often goes unnoticed by their owners and veterinarians unless it causes an obvious problem. Recognizing and treating these teeth can result in increased comfort and decreased infection and inflammation for our patients.
When a tooth fractures, a portion of the enamel and underlying dentin are broken off. Exposed dentin can result in increased sensitivity to temperatures (think teeth-grinding). It these are the only tissues involved, over time the living cells that regenerate dentin will help seal up the exposed surface and the tooth can remain vital.
Picture 1: A chronic fractured tooth of a 4-year-old golden retriever. The slab fracture in this case extended just beneath the gumline. Sutures were placed to replace the gingival flap elevated for the necessary odontoplasty/osteoplasty to maintain the periodontal health of the tooth.
However, if the pulp is involved in the fracture, this living element of the tooth will die. With compromise and exposure of the pulp, there is a period of immediate discomfort. Despite the associated pain, most animals do not show this increased sensitivity. Even less commonly will an owner notice the transient small amount of oral bleeding from the associated vessel. The majority of animals continue to eat, play and act normally, never showing that a problem exists.
As most animals don’t show signs of their discomfort at the time of the initial injury, veterinarians will rarely see few fractures with a “red” circle of exposed pulp. Most often, during an oral exam we diagnose a fracture with a visible hole, likely filled with darkened debris. Over a period of weeks, the exposed pulp nerve/blood vessels will die. This necrotic tissue becomes an isolated reservoir of bacteria that flourishes undeterred by the body’s normal immune system because there is no pathway for the body to infiltrate into the non-vital pulp chamber. As bacteria leaches out of the tooth into the bone surrounding the root apex, the body does mount a localized immune response to help keep the infection under control. It is when this localized response is overwhelmed that a more “classic” tooth root abscess forms. But all degrees of infection and inflammation can cause discomfort.
DIAGNOSING “HIDDEN” FRACTURES & INFECTIONS
As dental pain is often progressive, animals will compensate by making small adjustments to their everyday lives (chewing on the side opposite the fracture, less interest in toys, etc.). As owners, we will be challenged to notice these subtleties, but as veterinarians, there are signs we can find on our physical exams that an underlying chronic fracture exists. Uneven chewing habits can result in dental calculus that is asymmetrically worse on one side of the mouth. Comparison of the contralateral counterpart can reveal small differences of the contour of the shape of the crown that can be noticeable, even with a tooth covered in calculus. As calculus will take months to years to accumulate to the point of completely covering a fracture, the importance of regular thorough oral exams to diagnose and treat these fractures earlier is underscored.
An important side note concerns discolored teeth. According to a previous study2, over 90% of discolored teeth are non-vital teeth. While these teeth are not often fractured, some concussive force likely caused the pulp vessels to rupture, resulting in secondary inflammation from which the pulp cannot recover. Discoloration results from components of the blood seeping into the porous dentin. Bacteria travelling throughout our bloodstream will be able to migrate to the necrotic pulp, developing into a similar reservoir of infection found in fractured teeth.
Treatment options of a mature fractured tooth include extraction or root canal therapy. Extraction removes the complete tooth and infected tooth roots. Root canal therapy uses mechanical and chemical debridement to remove only the dead pulp, replacing it with an inert material and a restoration over the access sites to eliminate the risk of reinfection. The functional tooth and root remain. Unlike root canal therapy in humans, most of the animal’s original tooth crown is preserved and often a metal crown is not necessary.
Both procedures remove the source of infection and inflammation, alleviating the patient’s discomfort. While extraction of the tooth will require a longer recovery period with some short-term limitations on an animal’s diet and chewing activities, animals usually do very well following the recovery period after extractions. Root canal therapy maintains the functional tooth, and a faster return to normal behavior. While root canal therapy has an excellent success rate (>90%), treated teeth should have annual dental radiographs performed to ensure ongoing health.
Questions regarding fractured teeth or other oral issues? Email Dr. Jennings at firstname.lastname@example.org
Dr. Michael Jennings is a Board-Certified Dentist & Oral Surgeon at the Veterinary Specialty & Emergency Center. The Veterinary Specialty & Emergency Center operates state-of-the-art emergency and specialty veterinary hospitals that are open 24/7/365 in both Levittown PA and Philadelphia PA. For more information about our world-class emergency and specialty care, please visit VSEC on the web at www.VSECVET.com.
1. Golden, A. L., Stoller, N., Harvey, C. E. “A survey of oral and dental diseases in dogs anesthetized at a veterinary hospital.” JAAHA 1982 (18) 891-899
- Hale, F.A. “Localized Intrinsic Staining of Teeth Due to Pulpitis and Pulp Necrosis in Dogs.” JVD 2001 18(1) 14-20