Fractures involving the temporomandibular joint (TMJ) require a detailed understanding of the joint’s structure–function relationship to guide diagnosis and treatment. TMJ fractures may affect the condylar process and mandibular head and/or the mandibular fossa of the temporal bone. Among TMJ disorders, fractures represent the second most frequent condition in dogs and the most common TMJ disorder in cats. Recent evidence demonstrates that in immature dogs, rostral mandibular trauma is significantly associated with fractures involving the articular surface of the TMJ. The degree of fracture displacement is influenced not only by the magnitude and direction of traumatic forces, but also by the surrounding soft tissues and regional anatomy.

Management of TMJ fractures is complex and must consider multiple patient- and injury-specific factors, including age, dentition status, degree of fracture displacement, involvement of the articular surface, concurrent maxillofacial injuries, and occlusion.

Advanced diagnostic imaging plays a central role in treatment planning and surgical decision-making. Computed tomography (CT) and cone beam CT (CBCT) are the preferred modalities for accurate identification of TMJ anatomy, fracture morphology, and spatial relationships. Conventional CT is recommended in cases with suspected neurologic involvement, whereas CBCT is appropriate when neurologic and extensive soft tissue injuries are not present. A descriptive classification system based on anatomical topography of the condylar process-including the condylar base, neck, and head-assists in standardizing diagnosis and guiding therapy. An adapted version of the AO craniomaxillofacial (CMF) classification system has been modified for use in dogs and cats. Condylar process fractures are defined as fractures extending caudal to the mandibular notch, whereas mandibular head fractures directly involve the articular surface. Fracture complexity is categorized by the degree of fragmentation (none, minor, or major), and displacement is graded according to vertical apposition of fracture segments (complete, partial, or absent contact). In cases with multiple fractures, classification is assigned based on the most severe lesion.

Treatment strategies for TMJ fractures are broadly categorized into closed (conservative or minimally invasive) and open (surgical) approaches. Closed treatment is the most commonly employed strategy and is adequate in the majority of cases.

Conservative management does not involve opening the joint and may include muzzle therapy or rigid or elastic maxillomandibular fixation. Elastic therapy is often preferred, as it may reduce the risk of fibrosis or ankylosis, preserve joint homeostasis, and facilitate vascular supply to the healing tissues. In immature patients, the TMJ demonstrates substantial regenerative capacity, with bone healing typically occurring within two to three weeks. Active physical therapy should be gradually introduced after an initial healing period.

Open reduction and internal fixation (ORIF) of TMJ fractures remains uncommon in veterinary medicine due to the complex anatomy and small size of the involved structures. However, open treatment is indicated in cases of severely displaced fractures that impair mandibular opening or closure, fractures involving the mandibular fossa, displacement of the condylar process into the auditory canal or other critical structures, or severely fragmented injuries with a high risk for ankylosis or functional limitation.

In all cases, management of TMJ fractures should be planned within the broader context of concurrent maxillofacial trauma, with treatment goals focused on rapid return to function, restoration of pre-traumatic occlusion, preservation of range of motion, and maintenance of normal masticatory function.

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