Chapter 98 Fractures of the Maxilla
Fractures of the maxilla generally include all fractures rostral to the orbit—that is, the maxilla, nasal, and incisive bones. Most maxillary fractures occur as a result of automobile trauma, although dog bites and gunshots are also reported causes. Young cats and dogs (<2 years of age) are more likely to have maxillary fractures. Maxillary fractures present the veterinarian with some unique clinical management considerations. Concurrent head and thoracic trauma make anes-thetic management challenging, the placement of oral endotracheal tubes makes an accurate assessment of occlusion difficult, and providing postoperative oral nutrition can be critical in clinical success.
ANATOMY
• The incisive bones contain the upper incisor teeth; the maxilla bones contain the canine, premolar, and molar teeth.
• The bone between the roots of the teeth and the nasal cavity is very thin and easily damaged from trauma.
• The infraorbital artery and nerve travel through the infraorbital foramen located as an elliptical opening dorsal to the upper third and fourth premolar teeth.
• The palatal aspect of the maxilla is supplied by the major palatine artery that exits the major palatine foramen at the junction of the maxilla and palatine bones on the caudal aspect of the hard palate. The vessel travels rostrally medial to the teeth along the surface of the hard palate. There are numerous anastomoses among blood vessels of the maxilla.
SURGICAL PROCEDURES
Preoperative Considerations
• Obtain thoracic radiographs and manage any pleural space disease—that is, pneumothorax, hemothorax, diaphragmatic hernia, or pulmonary contusion (see Chapter 166).
• Record an electrocardiogram to assess for the presence of cardiac arrhythmias secondary to traumatic myocarditis.
Anesthetic Considerations
• To assess dental occlusion intraoperatively, place the endotracheal tube through a pharyngotomy incision.
Objectives
• Restore dental occlusion. Accurate anatomic reconstruction of fracture fragments will restore normal occlusion. Use an endotracheal tube placed through a pharyngotomy incision.
• Restore patent nasal passages in animals with severe fracture displacement or a blocked nasal cavity.
• Carefully handle soft tissues. Avoid entrapment of soft tissues, remove devitalized tissue, and avoid excessive elevation of soft tissues from bone.
• Avoid further dental trauma. Remove only teeth that are luxated or fractured. Leave teeth in the fracture site that will contribute to stabilization of the fracture.
