Oral surgery solutions: An unerupted canine tooth

Brett December 13, 2019

Unexpected complications can surprise even experienced veterinary specialists. Consider referring complex surgery cases to avoid taking on more than you bargained for.

In the February issue of dvm360, we looked at two difficult cases in veterinary dentistry. In this second article in this series examining challenging oral surgery cases, we’ll discuss how to know when referral is appropriate. If your dental surgery skills are less than refined, especially complex or unusual oral surgery cases are best left to board-certified experts.

Unerupted canine tooth in a cat and subsequent complications

A 2½-year-old domestic shorthaired cat was presented for evaluation of a mass at the site of a missing right maxillary canine tooth (104). History was unclear as to whether a tooth ever was present at the site of the mass. The mass was fluctuant and had a bony rim around its base (Figure 1). Dental radiographs were taken and revealed a canine tooth within the right maxilla (Figure 2). The apical extent of the tooth extended to the level of the furcation of the right maxillary fourth premolar (108). The presumptive diagnosis was a dentigerous cyst associated with the unerupted canine tooth. The mass was likely a result of the cyst impingement on the gingiva and bone at this location.

Figure 1: Image of a 2½-year-old domestic shorthaired cat presented for evaluation of a mass at the site of a missing right maxillary canine tooth. (All photos courtesy of Dr. Brett Beckman.)

Figure 2: A dental radiograph demonstrating a canine tooth within the right maxilla.

The surgical approach was similar to that utilized in a maxillary canine tooth extraction, with a mesial vertical releasing incision and a distal envelope incision in the sulcus (Figure 3). The bony rim was removed at the base of the mass, increasing exposure. The caudal portion of the cyst extended ventral to the orbit (Figure 4). The bone adjacent to the nasal cavity and the rostral maxillary recess was destroyed. No fluid existed within the defect, which was lined by a fibrous tissue consistent with that of a cyst (Figure 5).

Figure 3: The surgical approach was similar to that utilized in the maxillary canine tooth extraction.

Figure 4: A dental radiograph demonstrating a suction wand extending to the caudal extent of the defect.

Figure 5: An example of the material that was removed and submitted for histopathologic examination.

Careful removal of all discernible cyst material was difficult due to hemorrhage and obscurity of normal architecture. The pet owner was informed that although recurrence was possible, an aggressive approach involving complete removal provided a good prognosis. Closure was completed by excising excess marginal and palatal gingiva and suturing with 5-0 monocryl (Figure 6).

Figure 6: The closure was accomplished by excising excess marginal and palatal gingiva and suturing with 5-0 monocryl.

Histopathologic examination confirmed a dentigerous cyst. Dehiscence of a portion of the flap was recognized at the 30-day recheck, along with a small lip lesion secondary to canine tooth impingement (Figure 7). The lip lesion was not clinically significant and palpation revealed no discomfort. The defect was debrided and closed. Healing was complete at the subsequent recheck (Figure 8).

Figure 7: The surgical site 30 days after surgery showing dehiscence of a portion of the flap along with a small lip lesion secondary to canine tooth impingement.

Figure 8: Image demonstrating healing at the subsequent recheck.

Six months after the recheck, the patient presented with a space-occupying mass ventral to the orbit (Figure 9). Attempted excisional biopsy of what was thought to be residual cyst epithelium surprisingly revealed very aggressive undifferentiated neoplasia on histopathologic examination. Classification by immunohistochemical staining was declined due to a very poor prognosis based on pathology. The patient was euthanized several weeks later due to progression of the mass.

Figure 9: The patient six months after the 30-day recheck with a space-occupying mass ventral to the orbit.