Fractures of the interdental space and horizontal ramus are almost always open fractures. Wound debridement and flushing is extremely important. Nevertheless, infections of soft tissues as well as the bone are common. Therefore, establishment of ventral drainage is important.
In older or infected fractures, wound débridement is important. All infected bone must be removed with a curette or rongeur. Additional flushing is indicated.
3. Surgical technique
The fracture is reduced manually.
Two to four small incisions are prepared through the ventral aspect of the mandible at different locations of the diastema and pre-mandible and two 2 mm holes are prepared across the bone through each incision. If additional holes for the wire cerclage are required, they need to be prepared at this point in time.
Bilateral interdental wiring is applied, the wire ends partially tightened, and the wire loops in front of the incisor teeth left open.
The acrylic compound is then mixed and molded to the area to be reinforced at a thickness of 6 to 8 mm. Implants that are too thick impair chewing. The mold should have a U-shape so that the frenulum of the tongue is not restricted. Cold-curing acrylic is used to prevent thermal tissue damage.
Wires are subsequently threaded through the holes in the jaw and the soft acrylic but not tightened yet. Additionally two wire loops are threaded through the soft acrylic and around the incisor teeth (see arrows).
Once the acrylic has hardened the intraoral cerclage wires are tightened.
Subsequently the two wire loops around the incisor teeth are tightened as well.
Finally, the wire loops in front of the incisor teeth and the wire ends of the interdental wiring are tightened.
The four small incisions are closed routinely. In old, infected or open fractures, a drainage should be placed.
During the post-surgical period, the horse is confined to stall rest for one week and fed with soft fiber feed stuff; firm feed such as hay cubes, apples or carrots should not be fed. Antibiotics and anti-inflammatory drugs are given for 3 to 5 days or longer, if required, especially in open fractures. Intraoral cerclage and tension wires are cleaned once daily until their removal. Wound opening is cleaned and flushed daily with antiseptic solutions. After the fracture has healed acrylic splint and wire can be removed under sedation and local anesthesia.