Abstract
Fractures of the mandible and maxilla are reported in wild and managed dolphins. The dolphin mandible is uniquely specialized into two components that serve for both prey capture and sound reception. The cranial two-thirds of the mandible is composed of narrow, dense bone with a single row of conical homodont teeth which are primarily used for grasping prey and conspecific interaction. The caudal third of the mandible or ramus fans out into a wide, thin, hollow “pan” bone with a large medial foramen containing a large fat body which aids in sound reception and transmission to the auditory bullae. Dolphins with a fracture of the jaw or mandible may present with a host of clinical signs including acute inappetence, behavioral avoidance, mouth closed, malocclusion, torn gingiva, reduced mouth opening, or mouth agape. Depending on the force of the insult and the location of the fracture, jaw fractures in dolphins may be unilateral or bilateral, simple or comminuted, open and contaminated, or closed. Historically, cetacean jaw fractures have been managed with a broad range of methodologies, ranging from surgical fixation using external Kirschner pins to less-invasive splints to maintain fracture alignment. Four bottlenose dolphin cases will be presented evaluating location, method of fixation, and duration of healing. Two cases of caudal mandibular ramus or pan bone fractures were managed conservatively. Two cases of mandibular body fracture were managed surgically, one with interdental stainless-steel wire plus acrylic splint fixation and one with wire and internal fixation with a bone plate and screws.
Acknowledgements
The authors would like to thank the animal training staff and the veterinary technical and clinical laboratory staff at SeaWorld of California for their exceptional animal care and assistance with case management.
*Presenting author
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