Restorations essentially help protect previously damaged teeth from further injury. Primarily for cosmetic reasons, dramatic advances have been made in the past 20-25 years in human restorative dentistry. In veterinary dentistry, we have utilized the same technological advances for reasons of form and function. Although there are a few cases where cosmetics drive the pet owner to inquire about restoration of lost tooth structure, most of the time we are recommending restorations to seal exposed dentinal tubules, reduce sensitivity, retard plaque prevention, and return the tooth to normal function.
Primary indications for composite restorations in pets:
- Like humans, dogs can acquire cavities (caries). They are, however, nowhere near as common as in our own mouths. Caviites are related to oral bacteria in very specific tooth surface environments within the mouth. The incidence in dogs has been reported around 5%. When observed, they have usually formed the flatter surfaces of the molar teeth. The cavity lesion is created by bacteria and associated chemicals actually breaking down the hard, outer enamel layer of the tooth. Once the enamel is eroded through, the carious process can move extensively and quickly through the softer underlying dentin structure. If deep enough, the cavity may become very painful and eventually penetrate into the pulp and cause a dental abscess. If detected in time, these teeth can be preserved after cleaning out the diseased dentin and replacing it with the composite restoration.
- Cats, for all intents and purposes, do not get cavities like people and dogs do. They do, however, get what we refer to as orally exposed resorptive lesions (RLs) that are sometimes incorrectly called “cat cavities”. On occasion, one will hear of someone attempting to perform a restoration on a feline RL. This is an inappropriate treatment option.
- Developmental abnormalities in the tooth structure will sometimes be identified in young patients. Common terms used for these lesions are “enamel dysplasia” or enamel hypomineralization. These malformations can leave a defective to completely missing enamel layer on the tooth. As for chipped enamel of fractured teeth, this exposes the underlying dentin which has a porous surface of dentinal tubules and contains fluid in direct connection with the nerves of the pulp. The exposed dentin is not only sensitive, but has a rougher surface than enamel and will tend to collect plaque and calculus at an accelerated rate. Bacteria can penetrate dentin as well as cause it to disintegrate (necrosis). In these cases, removing any diseased or unsupported enamel, etching, and applying several layers of a dentinal bonding agent should help seal the exposed dentinal tubules and reduce sensitivity. To prevent plaque retention in the area of lost enamel, a bonded composite layer can be placed over the exposed dentin and polished to an enamel-like luster. Composites are not indestructible, but can stay bonded in place for many years providing protection and prevention of plaque build-up.
In some instances, composite build-up of lost tooth structure may restore the tooth to normal form and function and satisfy the client’s desires for a “normal appearing” tooth. As with any of these cases, consideration must be given to the age, size, personality, and function of the pet as well as the desires of the pet owner. In the right circumstances, composite bonded restorations can return lost tooth structure to normal form and function.