Veterinary Dental Services Newsletter

The difficult and often unpredictable task of performing root canal treatment with hand instruments is being replaced with motorized LSX® nickel-titanium instruments (Fig. 1). These instruments were specifically developed for the veterinary dentist to use when treating canine and feline patients and they have enhanced the efficiency and effectiveness of root canal treatment.

Fig1

Because LSX instruments are engine driven and operate at 2500 RPM they work faster and are more efficient in cleaning and shaping the canal walls. The non-tapered round canal shape created by the instrument conserves dentin while creating a larger apical preparation that is more conducive to irrigation and disinfection of the canal. Chemical irrigation and disinfection of the root canal is accomplished using alternating solutions of ethylenediamine tetraacetic acid (EDTA) and sodium hypochlorite or chlorihexidine solution. Canal irrigation can be aided by vacuum (suction) to remove the canal debris with the irrigation solutions.

After instrumentation and disinfection, the canal is filled with a sterile material. Most canal filling materials contain Gutta Percha (GP) a rubber-like product. GP Apical Plugs® (Fig. 2) match the LSX instrument sizes and when used with the recommended sealer they provide a more predictable fill and seal at the apical termination of the root canal (Fig. 3). The remainder of the canal can be filled with the operator’s choice of sealers and GP material. A restorative product is then used to seal the coronal access to the root canal.

Fig2

Fig3

Dental radiographs are an integral part of root canal treatment and they are used throughout root canal treatment to verify canal length as well as instrumentation. Radiographs taken at completion are used to verify root canal fill (Fig. 4) and for future use when verifying success of root canal treatment.

Fig4

Chronic Ulcerative Paradental Stomatitis

Chronic ulcerative paradental stomatitis (CUPS) is a form of periodontal disease that causes red, raised, ulcerated lesions in the buccal or labial mucosa where it rests against the teeth. Any area of the buccal or labial mucosa may be involved, however, most of these lesions are found in the area of the maxillary canine and fourth premolar teeth Although the condition is more common in the Maltese, German Shepard and Greyhound, it may be seen in any pure or mixed breed dog.

The cause of CUPS appears to be plaque intolerance where the immune defense system mounts a hyper response to the bacteria involved in periodontal disease. Diagnosis is based upon the characteristic “ulcerated lesions” in the buccal or labial mucosa where it lies in contact with plaque covered teeth. These teeth usually show other signs of attachment loss such as gingival recession, periodontal pockets and alveolar bone loss. Biopsy with histopathological evaluation of the lesions as well as blood counts, blood chemistry panels and urinalysis should be performed to rule out other possible inciting factors.

Treatment consists of thorough periodontal evaluation including radiographs, dental scaling, polishing, periodontal treatment and home care. Antibiotic therapy, pain management and immunosuppressive doses of corticosteriods are usually required to control the disease and provide enough comfort so that the owner can start home care. Home care consists of oral rinses, oral gels and tooth brushing. In refractory cases, tooth extraction will be required to treat CUPS and provide relief for the patient.

Fractured teeth are usually caused by either trauma to the head and mouth or from pets chewing on hard objects such as bones. Often fractured teeth go unnoticed by the owners unless they observe the injury causing the fracture. Veterinarians and technicians often find fractured teeth when performing oral examinations and dental treatment.

In order to determine the best treatment for fractured teeth, physical and radiographic evaluations are essential. Limited physical examinations can be done in the exam room while more thorough evaluations must be performed while the patient is anesthetized.

Once the patient is anesthetized, physical evaluation can be performed on the fractured teeth using a dental explorer, transillumination (directing a small concentrated light source on a tooth), and a periodontal probe.

A fine pointed dental explorer is used to probe the dental tissues for loose fragments, cracks, multiple fracture planes, dentin / enamel separation, exposed pulp chambers or pulp canals. A periodontal probe is used for exploring the extent of slab fractures that extend below the gumline. Transillumination can help reveal vertical fractures as well as determine tooth vitality. A vital tooth will have a translucent appearance while a non-vital tooth will appear opaque.

In order to complete the evaluation process, dental radiographs of the fractured tooth as well as the contra-lateral tooth should be taken.

A simple crown fracture involving only the enamel may only require smoothing the enamel (odontoplasty) with a fine diamond bur in a water-cooled high-speed hand piece as long as there is no radiographical evidence of abscess.

Crown fractures involving enamel and dentin without pulp exposure may also be restored using dental adhesives or sealants, and composites after taking a  dental radiograph to rule out signs of pathology. After the radiograph is assessed, the tooth can be smoothed and the enamel beveled. The  fractured tooth is then cleaned, polished with flour of pumice, etched and treated with a dental adhesive or sealant. A composite filling material can then be placed over the fracture to restore the tooth.           

If the fractured tooth has signs of a near pulp exposure (pink spot in the dentin over the area of the pulp chamber), a dental radiograph should first be taken to evaluate the fractured tooth for signs of pathology. If there are no signs of pathology then the near pulp exposure should be treated prior to restoring the tooth. Restoration would be performed as  previously described. 

If the vital pulp is exposed, performing a partial pulpectomy and medicating the pulp (pulp capping) may be an option provided radiographs of the tooth are normal. It is recommended that a partial pulpectomy and pulp cap be performed only in recent tooth fractures (24-48 hours since exposure in a mature dog, or up to 2 weeks exposure in a dog less than 18 months of age). After performing a partial pulpectomy and pulp cap, the tooth is restored with adhesives and composites as described above. If the fractured tooth with pulp exposure does not meet the criteria for partial pulpectomy and pulp capping then root canal therapy is indicated before restoring the fractured tooth.

A fractured tooth with a non-vital pulp usually presents as a crown or crown-root fracture and black (necrotic) pulp. This type of fracture can be treated with root canal therapy followed by restorative treatment with adhesives and composites or metal crowns.

It takes 6 -12 months for pathological signs of disease to appear on a dental radiograph, therefore follow-up dental radiographs should be taken of  any fractured tooth 6-12 months after treatment to ensure the pulp is healthy and there are no signs of pathology.If a client declines treatment of a fractured tooth with pulp exposure, then an extraction should be recommended. Leaving a tooth with pulp exposure untreated is not an option because it can result in an unnecessary and painful infection for the patient.