Welcome to the all-new Vetlearn

  • Vetlearn is getting a new home. Starting this fall,
    Vetlearn becomes part of the NAVC VetFolio family.

    You'll have access to the entire Compendium and
    Veterinary Technician archives and get to explore
    even more ways to learn and earn CE by becoming
    a VetFolio subscriber. Subscriber benefits:
  • Over 500 hours of interactive CE Videos
  • An engaging new Community for tough cases
    and networking
  • Three years of NAVC Conference Proceedings
  • All-new articles (CE and other topics) for the entire
    healthcare team

To access Vetlearn, you must first sign in or register.

registernow

  • Registration for new subscribers will open in August 2014!
  • Watch for additional exciting news coming soon!
Become a Member

Veterinary Forum October 2008 (Vol 25, No 10)

Dental Dilemma — What to Do When All Visible Enamel Is Gone

by Jan Bellows

    Saffron, an 8-month-old, 5.5-kg, spayed, mixed-breed dog, presented for evaluation of multiple enamel defects. During the patient's examination, however, missing clinically canine teeth also were discovered, and further radiographic evaluation while the patient was anesthetized revealed impacted mandibular canine teeth in addition to the enamel defects.

    See the glossary .

    The initial dental quandary was choosing which problem — the generalized lack of crown enamel or the impacted canines — to treat first. During the initial oral assessment while the teeth were being gently cleaned using a piezoelectric ultrasonic scaler, almost all of the residual enamel flaked off, leaving the tooth crowns without observable enamel (Figure 1). However, despite the severity of the enamel defects, it was decided to care for the mandibular impacted canines first because they were impinging on the mandibular canals, potentially interfering with the blood and nerve supply to the rostral mandible (Figure 2 and Figure 3). After surgery, tramadol at 2 mg/kg PO bid and firocoxib at 5 mg/kg q24h for 4 days were dispensed, followed by 0.1 mg/kg of meloxicam as pain management until the enamel defects could be addressed.

    Treatment measures

    Six weeks after oral surgery to remove the impacted canine teeth, the dog was premedicated with hydromorphone at 0.1 mg/kg combined with acepromazine at 0.010 mg/kg IM. After waiting 20 minutes, 0.5 mg/kg of diazepam and 10 mg/kg of ketamine were administered intravenously to induce anesthesia. The dog was intubated and maintained on 2% isoflurane. The temperature was controlled in a warm-air Bair Hugger (Arizant Healthcare). Intraoral survey films appeared normal, except for the lack of enamel.

    The treatment objective was to keep the teeth vital without causing discomfort. To accomplish this, the exposed dentinal tubules normally covered by protective enamel needed to be sealed. A fifth-generation self-etching dentin primer and adhesive bonding agent (see box) followed by a sealer application was chosen (Figure 4).

    The teeth crowns were cleaned ultrasonically and polished with fine pumice, irrigated, and blotted dry with cotton gauze. Five drops of ALL-BOND SE (Bisco) Parts I and II were dispensed into the mixing well and mixed until uniformly pink (Figure 5 and Figure 6). Two coats of the mixture were applied to all teeth on the maxillary right quadrant (Figure 7). Compressed oil-free air was used to gently dry the liquid (Figure 8). The area was polymerized for 10 seconds using a polymerizing unit (light cure gun, ESPE) at 500 mW/cm2 (Figure 9). To further protect the teeth, ALL BOND SE LINER (Bisco) flowable composite was thinly applied through the supplied syringe over the crown. The area was again light-cured — this time for 20 seconds. The dentin bonding agent and flowable composite were applied and the process repeated to the teeth of the left maxilla, followed by the right and left mandibular teeth (Figure 10).

    When the pet was sent home, the client was given information on the various plaque control methods, including daily toothbrushing and sodium hexamethaphosphate wipes (Dentacetic Wipes, Dermapet), and advised to apply plaque barrier gel (OraVet, Merial) daily to the crowns (off-label use).

    Follow-up examination 3 months later showed stage 1 gingivitis from the accumulation of plaque at the gingival margin (Figure 11). The client was instructed to rub the end of a cotton swab at the buccal and labial free gingival margins as part of the plaque control program.

    Our plan for the future is to follow the dog's progress at least every month and with an annual oral assessment, treatment, and prevention (ATP) visit, including oral radiography and reapplication of the dentin bonding agent and flowable composite in areas of dental defects.

    Discussion

    Enamel prisms are deposited by the enamel organ in a definitive pattern that forms the crown of the tooth. Enamel normally fully covers the crown, protecting and insulating the underlying dentin and pulp from the oral environment. A local or general environmental or inherited disturbance may interfere with this process and result in defective development. The degree of the defect (hypoplasia) varies from mild, shallow depressions, extensive grooves or pits arranged in horizontal rows around the crown extending into the enamel as far as the dentinoenamel junction to complete lack of enamel.

    There are three recognized stages of enamel development: matrix formation where the enamel proteins are laid down, mineralization, and maturation. In the early stage of mineralization, the enamel appears dull white and is relatively soft. During the maturation phase, hard translucent enamel replaces the opaque enamel. The ameloblasts in the developing tooth are extremely sensitive to external stimuli, which can create abnormalities in developing enamel. The final crown appearance represents a record of all formation stages as well as significant insults received during tooth development.

    This case was different from the typical enamel hypoplasia presentation in which there are several discrete areas of enamel loss exposing underlying dentin. Here during ultrasonic scaling, virtually all the enamel flaked off. Therapy options in this case included full-mouth extraction, application of dentin bonding agents to seal the exposed dentinal tubules with or without application of microhybrid composite, or crown restoration using semiprecious metals or ceramics.

    Because of the dog's young age and concomitant thin dentin wall, removing additional dentin mass for crown preparation was deemed not in the patient's best interest. To seal the exposed dentin tubules protecting and insulating the underlying pulp, a dentin primer and adhesive were chosen to allow bonding of resin-based composite to the permanent teeth.

    Adhesive systems currently follow either a total-etch or a self-etch technique. Total etch requires three steps. It involves using an etchant to prepare any remaining enamel while removing the dental smear layer and decalcifying the dentin. After rinsing the etchant, a primer is applied and penetrates the dentin, preparing it for the bonding agent. Finally, a bonding agent is applied to the primed crown. Self-etch adhesive systems that combine the primer and the adhesive also are available. Because systems require multiple steps, errors in any step can affect clinical success. Attention to technique for the specific adhesive system is critical to success.

    In time, the dentin tubules decrease in diameter and the width of dentin simultaneously increases. The plan is to reapply the dentin bonding agent and flowable composite yearly for 3 years based on clinical and radiographic findings.

    Bibliography

    Foil C. Developmental disturbances in teeth. In: Hoskins JD, ed. Veterinary Pediatrics. Philadelphia: WB Saunders; 1993:366.

    Nik-Hussein NN, Majid ZA. Dental anomalies in the primary dentition: distribution and correlation with the permanent dentition. J Clin Pediatr Dent 1996;21(1):15-19.

    Regezi JA, Sciubba J. Abnormalities of teeth. In: Oral Pathology: Clinical-Pathologic Correlations. Philadelphia: WB Saunders; 1993:494-501.

    Shafer WG, Hine MK, Levy BM. Developmental disturbances of oral and paraoral structures. In: A Textbook of Oral Pathology, ed 3. Philadelphia: WB Saunders; 1974:2-80.

    Wiggs RB, Lobprise HB. Developmental pathology. In: Veterinary Dentistry: Principles and Practice. Philadelphia: LippincottRaven; 1997:105-112.

    A companion article "Unerupted Mandibular Canine Teeth," which appeared in the August 2008 Dental Dilemma column, contains more detailed information regarding initial presentation and evaluation.

    NEXT: Editor's Note — Inspire professionalism

    didyouknow

    Did you know... Chronic alveolitis/osteitis is seen in older cats and presents as a supereruption of the maxillary canines with thickening of the alveolar bone or bulging.Read More

    These Care Guides are written to help your clients understand common conditions. They are formatted to print and give to your clients for their information.

    Stay on top of all our latest content — sign up for the Vetlearn newsletters.
    • More
    Subscribe