Case report: Removing traumatically displaced teeth from a dog’s nasal cavity via an intraoral approach

On clinical examination, Arlo had an audible nasal airflow obstruction, purulent nasal discharge, and fractures of both upper deciduous canine teeth. The fractured teeth were removed under general anesthesia, and dental radiographs showed no evidence of structural changes to the nasal cavity.

A swab of the nasal cavity was collected and sent for culture and sensitivity. While the results were pending, Arlo was started on a course of amoxicillin-clavulanic acid. Although the culture result showed growth of Enterobacter asburiae with resistance to amoxicillin-clavulanic acid, the pathologist suggested that this was likely a normal commensal of the nasal cavity and not representative of a true infection. The primary care veterinarian decided to continue the course of antibiotics because, clinically, there was a reduction in nasal discharge.

The nasal discharge recurred when the course of antibiotics was completed, and the primary care veterinarian sought the author’s (AC) advice. Due to the traumatic injury, there was likely to be a comminuted maxillary fracture, altered maxillary growth, and possible displacement or impaction of the permanent teeth, particularly the maxillary canines. A dorsoventral radiograph of the maxilla (Figure 1) showed that the right maxillary adult canine tooth was sitting more medially than would normally be expected. At this stage, it was recommended to monitor the eruption of the adult teeth closely.

Arlo was presented again 6 weeks later due to nasal stertor, reduced exercise tolerance, and sneezing. Obvious maxillary brachygnathism had developed, suggesting damage to maxillary growth, resulting in a posttraumatic class III malocclusion. Arlo was referred to our hospital for further investigation and treatment.

Figure 1. Preoperative occlusal-view radiograph shows displaced and impacted teeth 104, 106, and 204 (arrowheads). Also note missing tooth 105 and remnants of tooth 107.

Further findings

Clinical examination revealed a missing right maxillary canine tooth (104), and only the incisal edge of the crown of the left maxillary canine (204) was visible. Airflow through the nasal cavity (particularly the right nostril) was restricted, and an audible stertor was still present during normal, relaxed respiration. Due to the history of trauma, unerupted and possibly displaced maxillary permanent canine teeth—the mandibular canines already were erupting into a normal position—as well as the altered maxillary growth and restrictions in nasal airflow, a decision was made to obtain a CT scan.

The CT scan (Figure 2) revealed that both maxillary canine teeth were displaced and impacted into the nasal cavity. The root of tooth 204 was within the left nasal cavity, and the whole of tooth 104 was horizontally and palatally displaced within the nasal cavity, being close to the vomer and nasal septum. Exostosis was noted associated with and encapsulating tooth 104. The right maxillary second molar tooth (106) appeared to be impacted, also.

Figure 2. Axial-view CT scan shows both maxillary canines displaced into the nasal cavity, as well destruction of maxilloturbinates and deviation of the vomer to the left side.

Surgery was selected as the best option to relieve the respiratory distress caused by the displaced maxillary canine teeth. It was assumed that maxillary fractures caused by the original trauma would be present, leading to a post traumatic class III malocclusion due to alteration in the normal development of the incisive, nasal, and maxillary bones.

Surgical correction

Arlo was premedicated with acepromazine 0.02 mg/kg and methadone 0.3 mg/kg given subcutaneously. An intravenous cannula was placed in the cephalic vein, and general anesthesia was induced with slow titration of alfaxalone 2 mg/kg to effect. Arlo was maintained on oxygen and isoflurane with a cuffed endotracheal tube. The dog’s vital signs were monitored closely throughout surgery and no complications were noted. Cefazolin 22 mg/kg was administered intravenously every 90 minutes during surgery, and a continuous-rate infusion of fentanyl at 4 µg/kg/hr was maintained and titrated as required to ensure ongoing pain relief throughout the procedure.

Dorsal and ventral rhinotomies are the most frequently reported surgical approaches to the nasal cavity for removal of foreign bodies or masses. Initially, a dorsal rhinotomy was considered the best approach to the impacted teeth. However, it was quickly determined that a dorsal approach would be too invasive, and a rarely described intraoral lateral rhinotomy approach was considered the best and least invasive approach to the displaced teeth.¹

The dog was positioned in right lateral recumbency and a left side caudal maxillary nerve block (1 mL lidocaine 2%) was performed. A pharyngeal pack was placed to protect the oropharynx. A few millimeters of the crown of tooth 204 were visible in the oral cavity.

The root bulge of tooth 204 was palpated just under the labial bony plate. On the CT scan, the root of this tooth communicated with the left nasal cavity. A left lateral rhinotomy via an intraoral approach was performed. Using a Molt No. 9 periosteal elevator, a triangular labial mucoperiosteal flap was raised in the area. Labial bone was removed with an air-powered spinal handpiece and bur,and the impacted crown and root of tooth 204 became visible. With gentle luxation and elevation of the root (size 5 dental elevator), the tooth was extracted with spring loaded-extraction forceps (Figure 3).

Figure 3. A left lateral rhinotomy (intraoral approach) was completed and tooth 104 extracted

The surgical site was vigorously curetted of any granulation tissue and flushed with saline prior to closure of the mucoperisoteal flap. The flap had a periosteal release at its base to allow for tension-free closure with simple interrupted 3-0 absorbable sutures.

The dog was then placed into left lateral recumbency. A right caudal maxillary nerve block was administered similar to that on the left side. There was no evidence of the crown of tooth 104, but the CT scan indicated that the tooth was an abnormal stubby shape, more horizontally impacted (closer to the midline), and more caudal or distal compared with tooth 204. It was noted that tooth 106 was missing on oral examination, although it appeared on CT to be impacted.

Tooth 104 was approached again via an intraoral lateral rhinotomy approach, a large triangular mucoperiosteal flap with a vertical releasing incision just caudal or distal to the maxillary third incisor (103), and a horizontal release extending caudally or distally to the mesial surface of tooth 108.

A large lateral rhinotomy via an intraoral approach was performed to access the crown of impacted tooth 104. Tooth 106 was identified and removed in its entirety prior to searching for tooth 104. The abnormal crown of tooth 104 was identified and the rhinotomy was extended caudally, due to the horizontal impaction of tooth 104, allowing for a path of delivery of the tooth. A moderate amount of new bone growth surrounded this tooth, and the lateral component of this new bone growth had to be removed. Once the crown and root were visualized, small dental elevators (sizes 2 and 3) were used to mobilize the tooth, and the intact tooth was extracted through the osteotomy site (Figure 4).

Figure 4. A right lateral rhinotomy (intraoral approach) was completed, and poorly developed tooth 204 was extracted.

The extraction site was again curetted of granulation tissue and flushed with sterile saline. Again, closure of the mucoperiosteal flap with a tension-free releasing incision of the periosteum was performed as per the tooth 204 site. Full extraction of all displaced teeth was subsequently confirmed (Figure 5).

Figure 5. Postoperative occlusal view shows the rostral maxilla (CR7 size 4 phosphor plate). Note complete extraction of teeth 104, 106, and 204. Also note deviation of the vomer to the left side, exostoses on the right-side nasal cavity, and an abnormal maxilloturbinate pattern, especially on the right side nasal cavity.

Recovery and outcome

Arlo’s recovery from anesthesia was uneventful, and the respiratory noise was improved in the immediate postoperative period. Arlo remained in the hospital overnight and was discharged the following day as the dog was experiencing no breathing difficulties and was eating and drinking normally. A 5-day course of oral amoxicillin-clavulanic acid 20 mg/kg twice daily was dispensed, and meloxicam 0.1 mg/kg orally once daily was dispensed for 7 days to manage postoperative pain and inflammation.

Arlo was reexamined by his primary care veterinarian 2 weeks after surgery and then again at 2 months after surgery, at which time a mild nasal stertor remained. This was most likely due to scar tissue/exostosis caused by the initial injury, and it is unlikely to ever resolve completely. The surgical sites healed well without complication and with excellent cosmesis. The traumatic malocclusion is still present (Figure 6), but the owners are happy with Arlo’s progress. Arlo remains an active, energetic puppy. (Figure 7).

Figure 6. This is Arlo at his recheck appointment, 2 weeks after surgery. Note that a left dorsal rhinotomy approach was started, but soon abandoned, in preference for the intraoral approach. Also note the posttraumatic (class III) malocclusion

Figure 7. A much happier Arlo 2 weeks after surgery.

Anthony Caiafa, BVSc, BDSc, MANZCVS, is both a veterinarian and a human dentist and works in both fields. He is a dental consultant at North Coast Veterinary Specialists and Referral Centre in Sunshine Coast, Queensland, Australia, an associate professor at the University of Melbourne, and a guest lecturer at James Cook University in Townsville.

Casey Gordon, BVSc (Hons),is a small animal surgery intern at North Coast Veterinary Specialists and Referral Centre in Sunshine Coast, Queensland, Australia.Her goal is to become a surgical resident and ultimately a specialist surgeon.

Reference

1. Hoyer N, Bannon K, Bell C, Soukup J. Extensive maxillary odontomas in 2 dogs: diagnosis, pathology, and management. J Vet Dent. 2016;33(4) 234-242. doi:10.1177/0898756417690051