Symphyseal fracture repair in cats has been performed traditionally by placing a ligature wire circumferentially around the
anterior mandible and securing the right and left mandibular bodies by tightening the ligature wire. This method is not only
invasive, but often results in an unstable symphyseal reduction because of the faculty of ligature wire to stretch over time.
Pharyngealtracheal intubation allows a surgeon to access the occlusion as repair is being performed.
In contrast, a non-invasive procedure presented in this article employs the use of a chemically-cured dental composite, which
is less traumatic, easier to perform and results in a stable symphysis.
Anesthesia for this procedure can be accomplished using gas anesthesia or injectable anesthesia. The preferred method would
be with conventional induction, intubation and gas anesthesia for maintenance. This allows the practitioner to maintain an
airway and proper ventilation in an already traumatized and therefore compromised patient.
In order to be able to evaluate proper occlusion later in the procedure, pharyngealtracheal intubation with a retropharyngeal
exit for the endotracheal tube can be employed or the use of a shortened and very firmly secured endotracheal tube can be
used. With this method, for very short periods of time, the adapter is removed and the endotracheal tube is pushed back into
the mouth in order to evaluate the occlusion.
The second anesthetic protocol that can be employed is one using injectable anesthesia. Though easier for occlusion evaluation,
because of lack of proper airway and ventilation maintenance, this is not the preferred method of anesthesia.
Note: Regardless of the type of anesthesia used, all procedures should incorporate the use of local anesthesia. Lidocaine
or bupivicaine, at no more than a total of 2 mg/kg, can be injected into the mucobuccal fold in the symphyseal area.
There are several chemically cured dental composites available on the market that will work equally well for this fracture
repair. This procedure details the use of Pro Temp Garant by Espee ™ (Photo 1). Dental composites are packaged in two-part
canisters with one side containing the base and the other the catalyst. When mixed by the plunger action of the Garant, the
base and catalyst are combined in the nozzle and deliver a thick, flowable material that hardens in two to three minutes.
Photo 1: Fracture repair composite applicator.
Step 1: If present, soft-tissue lesions are cleaned, debrided and sutured. A local anesthetic block is injected into the mucobuccal
fold in the symphyseal area (Photos 2-3).
Photo 2: Soft-tissue lesions should be cleaned before a local anesthetic is applied.
Photo 3: Local block is applied.
Step 2: The lower canines are ligated together into proper alignment using a 26-gauge ligature or a 3-0 suture wire in a figure-eight
pattern. If necessary, a shallow groove can be made with a dental bur on the buccal aspect of each canine to help keep the
wire in place (Photos 4-5).
Photo 4: A shallow groove made with a dental bur.
Photo 5: A groove holds the wire.