 Hello everyone. Welcome back to OMFS lecture series. In the previous lecture we had discussed about the basic anatomy of mandible and how the masticatory muscles act upon mandibular fractures. Today's lecture will deal with the general principles of mandibular fracture management and closed reduction technique. The very first principle is to carefully evaluate the patient's general physical status. Because any force large enough to cause mandibular fracture is capable of injuring other organ systems as well. Therefore examine the patient for concomitant head and spinal injuries, pneumothorax, fracture of limbs, ruptured spleen or other facial injuries. The next principle is to diagnose and manage the fracture methodically. What does it mean? Patients rarely die of mandibular fractures. Hence do a thorough evaluation of patient history, local physical and radiological examination. It is not an emergency if the patient's general status is satisfactory. But it doesn't mean that you unnecessarily delay the treatment either. Associated dental injuries are common findings which needs to be evaluated and treated along with the fracture. We shall discuss on the management of tooth in the line of fracture later in this lecture. Re-establishment of occlusion is the primary goal in the treatment of mandibular fractures because an improper treatment results in maluploasion and function can be seriously compromised. Another principle is to treat the mandibular fractures first in case of multiple facial fractures. This is because to assemble and arrange the facial bones in position reconstruction of mandible is considered necessary. Intermaxillary fixation time should vary according to the type, location, number, severity of mandibular fractures, the patient's age, health and also the methods used for reduction and fixation. Therefore, IMF duration is in the same for every patient and for every fracture. Prophylactic antibiotics should be used for compound fractures. Compound fractures are the ones which communicate with the external environment through a wound in the skin, mucosa or pedodontal ligament. Therefore, prophylactic antibiotics can control the spread of infection. The nutritional needs of the patient also have to be taken care of because the treatment might fail if the patient's metabolism is not normal. Let us now move on to the steps or principles of fracture management. There are four steps, the reduction, fixation, immobilization and rehabilitation. The term reduction means to recreate the normal anatomy of the fractured bone. By reducing a fracture, we are realigning the fracture fragments that they heal in their original positions. After reduction, even though the bone fragments are aligned in the anatomical position, they are still potentially unstable. So we do a fixation of the fracture. That means the fracture fragments are held together and stabilized using special implants like plates, screws or wires. The third step immobilization refers to the process of holding the bone in place to prevent the injured areas from moving as it heals. Like you wear a cast or splint in case of limb fractures, various immobilization techniques are used in manipular fractures also. The final step is the rehabilitation or to restore the normal function of the bone. This is done through physiotherapy and exercises. Before moving on to the various treatment options of fractured mandible, let us quickly have a look at how to deal with the tooth that is within the fracture line. As you can see in this radiograph, canine and third molar lie within the fracture line. There are a few complications associated with tooth in the line of fracture. This tooth is a potential impediment to fracture healing. It converts a simple fracture into a compound one because through the tooth, the fracture is exposed to the external environment. Through the tooth, this is the fracture, so through the tooth it gets exposed to the oral cavity, which is an external environment. Hence it is a potential neither of infection. The tooth may be damaged and it subsequently becomes necrotic. Also, if there is a pre-existing pathology associated with the tooth, it can aggravate or invade the mandible. There are a few indications for removal of tooth in the line of fracture. Longitudinal tooth fracture, subluxation or dislocation of the tooth, pediapical infection, infected fracture line and acute pericoronitis are all in absolute favor of removing the tooth from fracture line. In one of the initial slides, it was mentioned that the duration of inter-maxillary fixation depends on various factors. So, here is a guideline for the time of immobilization for fractures of tooth bearing area of the mandible. According to this guideline, the period of immobilization for a young adult with fracture of the body of the mandible receiving an early treatment and in which the tooth is removed from fracture line is three weeks. So, in this particular scenario, the time period of inter-maxillary fixation is three weeks. Any deviation from this will alter the IMF period. Just like you add one more week, if the tooth is retained in the fracture line and if the fracture is at the symphysis. You may add a week or more if the patient is over 40 years of age, whereas in children, immobilize the fracture site in two weeks. Having discussed the basic principles of fracture management, we shall now move on to closed reduction. You know that fracture reduction is nothing but realigning the fracture fragments into their normal anatomical position. By closed reduction, you are reducing the fracture without directly seeing it. There is no incision made to access or visualize the fracture and not every fracture is meant for closed reduction. There are certain relative indications like grossly communicated fractures. Because of the excellent blood supply to the face, small fragments of bones will combine and heal if the associated periosteum is not disturbed. The communicated fracture is managed like a bag of bones and the clinician utilizes closed techniques to establish normal occlusion. In non-displaced favorable fractures, the simplest possible means should be used to reduce and fix fractures. Hence, you don't perform open reduction unless absolutely indicated. Fracture repair is also dependent on the soft tissue coverage and vascular supply. Therefore, fractures exposed by significant loss of overlying tissues are created by closed reduction until the soft tissue coverage is established by flaps or grafts. In edentulous mandibular fractures, again the vascular supply is compromised. Open reduction requires stripping of periosteum which further inhibits fracture healing. Open reduction with implants carries the risk of damage to developing tooth buds. Therefore, in majority of pediatric mandibular fractures, closed reduction is performed with specialized wiring techniques. Fracture of coronoid is usually simple with little displacement. Treatment is usually carried out if the occlusion is compromised or the fracture segment impinges on the zygomatic arch. Most condylar fractures are created via closed reduction unless absolutely indicated for open reduction. This topic shall be covered in detail in subsequent lectures. Moving on to the different techniques of closed reduction and indirect skeletal fixation. The fracture is reduced without exposing it and the fixation is also indirect, meaning the fracture is stabilized in position by applying devices external to it. The techniques are as follows, direct interdental wiring, eyelet or IV loop, continuous loop wiring, arch bars, cap splints, gunning type splints and biphasic pin fixation. All these techniques may be performed on a dental chair under leukronostasia. Direct interdental wiring or Gilmour's technique. It is a simple and rapid method of jaw immobilization. Here a 15 centimeter long pre-stretched stainless steel wire is passed around each tooth which emerge through the interdental space. The wire is placed around the necks of the teeth and the two ends are twisted and tightened. This is performed on both the arches and the opposite wirings are twisted together as you can see in the second diagram. The opposite wirings are tightened together. This way maxilla mandibular fixation is accomplished. The main disadvantage of this technique is that if one of the wiring breaks or needs a tightening then the entire wiring has to be removed. Extortion of tape is another disadvantage. eyelet or IV loop is a relatively simpler technique provided there is sufficient number of quality teeth. This is how an eyelet looks like. eyelet wires are made by twisting a 15 centimeter wire around a pin of 3 mm diameter. It has two ends of equal length. The wiring technique is shown in this diagram. These two ends will together pass through interdental space. Each end is then taken out to the bacterial region again through the adjacent interdental areas. The loop is then engaged in close fit interdently. The distal end is then turned and passed through the loop which is then twisted with the mesial end and secured. With a full complement of teeth eight eyelets are placed in the upper jaw and six in the lower jaw. Later intermaxillary fixation is performed by passing wires through the opposite loops. This diagram shows a completed eyelet wiring. Several modifications have been made to the eyelet wiring techniques in accordance to case types. Arch bars are indicated in fractures with insufficient dentition, simple dental alveolar fractures or even in fractures with multiple tooth bearing fragments. There are several designs for arch bars. This model is called the Eric's arch bar. It is basically a stainless steel bendable band with several cleats attached to it. The arch bar is secured to both jaws using wires and while doing this make sure the cleats open gingively and not occlusively. It faces the gingiva. Maximum anterior fixation is then performed using box shaped wires. Cap splints are indicated in fractures of tooth bearing segments where the teeth are periodontally compromised or it is also used in cases where a portion of the body of mandible is missing. A custom made cap splint is fabricated using specialized impression technique. It is then fixed to the mandible and fracture reduction is achieved. Gunding splints are used to reduce favorable and undisplaced fractures of indentuous mandible. It is an acrylic splint in the form of a modified denture with bite blocks in the posterior region and an open space in the anterior region to facilitate fielding. It is contraindicated in unfavorable or severely displaced fractures. Bifasic pin fixation is a closed technique which uses external fixation. Though the fracture is not exposed, a stab incision is made on the skin to fix two screws each on either side of the fracture. As you can see in this diagram, two screws or pins are fixed on either side of the fracture. These pins are locked and they will have an extension out of the skin. The pins are removed after fracture healing. Bifasic pin fixation is used in indentuous fractures where intermaxillary fixation is not feasible. It is also used in comminuted fractures where there are requirements of bone grafts. It is contraindicated in evaluated or grossly contaminated tissues and inserting bone anomalies like osteoporosis and osteosclerosis. With the various closed reduction techniques explained, let's look into the advantages and disadvantages of closed reduction. It is inexpensive, convenient, conservative and easy not requiring a great operator skill. The disadvantages are that the function might be compromised because of incomplete stability and reduced range of motion. Long duration of intermaxillary fixation will also lead to poor oral hygiene, TMG changes, reduced foot take and weight loss. We have thus discussed the principles of magular fracture management as well as the closed reduction techniques. The open reduction and fixation shall be discussed in the next lecture. Thank you.