Biological surgical treatment of unilateral or bilateral fractures caudal to the 3rd mandibular molar tooth should be based on anatomical site, patient size and age, fracture configuration and desired function. CT imaging is essential. Skull or dental radiographs are not adequate to assess the extent of the fractures.
Elastic therapy fixation is useful in cases with severe soft tissue swelling in the caudal mandible and pharyngeal area.
Elastic therapy restricts jaw movement without compromising airway functionality.
Placement of anchors
With the patient in dorsal recumbency, a small skin incision is made at the alveolar bone, between the canine and the first premolar teeth, on both maxillae and mandibles.
Note: this technique cannot be used in small dogs and cats because the screws are too large.
Intermaxillary fixation (IMF) screws are made of 316L stainless steel. They are self-drilling and self-tapping. Pre-drilling may be necessary due to density of the bone.
The IMF screw is designed with a large flat head and a short shaft. The holes are used for elastic bands. When using a chain, the screw head holds it in place.
In medium to large breed dogs, the 8 mm size is the correct screw.
The IMF screw is fully inserted through the drill holes.
Elastic chains application
2-4 orthodontic elastic chains are passed between the screws placed on the mandible and maxilla. The screw holds the elastic chain either by passing through the hole or the chain goes around the screw head.
A flowable dental composite may be applied to cover the screws to avoid soft tissue trauma and to help keep the chain in place.
The patient should wear an Elizabethan collar until removal of the construct.
Multimodal analgesia is recommended. Non-steroidal medication for 10-14 days and opioids for the first 5 days post-surgery as needed.
The construct should be cleaned at least once daily using 0.12% chlorhexidine gluconate solution. Another option is to use a water-flossing device.
Weekly clinical recheck to assess function and to gradually loosen the chain is indicated. The goal is to gradually increase the range of motion allowing return to normal function.
The construct is kept in place for 4-6 weeks. Follow-up CT at 6 weeks is recommended. The construct is removed when normal range of motion is achieved.
After screw removal, the mucosa can be sutured with 5-0 poliglecaprone 25 in a simple interrupted fashion.
Panting is not possible, therefore exposure to heat is avoided. To prevent damage to the construct, avoid toys and contact with other animals. If the patient vomits, remove the chains and allow the patient to open its mouth to avoid aspiration pneumonia.