Description
Palatal defects can be either congenital (i.e., palatal clefts) or acquired (i.e., oronasal fistulas).
Palatal clefts result from disturbances in the growth of tissue processes or their fusion during embryologic development. Generally, orofacial clefts affect 3% of puppies (cleft lip 26%, cleft palate 59% and a combination of cleft lip and palate 15%). The general incidence of orofacial clefts as well as the incidence of specific cleft phenotype varies across breeds. Brachycephalic breeds and mastiff/terrier breeds are predisposed to orofacial clefts. Clefts are considered very rare in the cat.
Animals with congenital palatal defects are usually presented due to difficulties nursing/drinking - gagging, coughing, or sneezing while eating, and possibly signs of respiratory tract infection. Oral examination findings may include malocclusion, and abnormal number and/or shape of teeth, mostly associated with maxillary incisor teeth. Complete blood count and serum biochemistry are recommended, although the results are usually within normal limits. Thoracic radiographs are indicated to rule in/out aspiration pneumonia. In the assessment of patients for a palatal surgery, size and shape of the defect are evaluated under general anesthesia. Advanced imaging (CT) is recommended to fully evaluate the defect and plan treatment.
Surgical correction of congenital palatal defects is preferably delayed until the animals are at least 3-4 months old, or, in selected cases, until permanent dentition has fully erupted allowing maximum amount of tissue available for repair. Complications (oronasal fistula formation) has been more commonly reported in dogs older than 8 months of age at the time of initial repair. Similarly, more complications have been observed in dogs with a history of failed surgical repair or in dogs weighing less than 1 kg at the time of initial repair. Surgical technique will depend on the location, size and shape of the palatal defect. The best chance of success is with the first surgical procedure, but sometimes closure needs to be staged.
Oronasal fistula is an acquired communication between the oral and nasal cavities caused in dogs and cats by trauma (e.g., bite wounds, blunt head trauma, gunshot wounds, electrical burns, foreign body penetration and pressure necrosis, including malocclusion and nasopharyngeal stents), neoplasia, radiation necrosis, periodontal/dental disease and dehiscence after surgical treatment.
Oronasal fistulas are most commonly diagnosed due to severe periodontitis. These are most commonly repaired by a single-layer vestibular flap after the affected tooth/teeth was/were extracted and the area cleaned and debrided of the epithelium. However, double-layer techniques may also be used.
Oronasal fistulas at other locations will require different techniques, such as transposition flap, split palatal U-flap, angularis oris flap or myoperitoneal microvascular free flap.
Acute midline palatal defects, commonly associated with a high-rise syndrome in cats, are treated as an emergency, if the animal is stable, and the technique similar to von Langenbeck repair is commonly used.
RACE Approved Tracking #20-1066230