In any maxillofacial trauma that involves tooth-bearing segments, it is essential that the proper occlusal relationship be reestablished. This is important for the restoration of normal masticatory function. The occlusal relationship between the maxillary and mandibular dentition also determines the relationship between the bones of the lower central face. Direct alignment of bone fragments virtually always takes second place to alignment of the occlusion. This is particularly true when the middle third of the face is collapsed, because the mandibular height is used to reestablish facial height, and the occlusion is a key component of the relationship between the mandible and the maxilla.
Occlusion is best reestablished using arch bars, which are pliable metal bands with hooks for wires or rubber bands that are wired directly to the teeth. The Errich arch bar is the most common arch bar in the United States. Other options include Ivy Loops, although these only stabilize a few teeth rather than the entire dental arch. They also do not provide tension banding across the mandibular dental arch. A variety of other options are available as well, and a recent innovation has been the use of screws for MMF. Even though these can be placed quickly and easily, several disadvantages are apparent, the most common of which is the frequent penetration of tooth roots when placing them. All arch bars tend to pull the dentition lingually, but the more inferior and buccal positioning of the screws when screw MMF is used tends to increase this tendency.
Once arch bars have been placed, they can be used to hold the patient in MMF. This is done by placing wires or rubber bands between the hooks on the upper arch bar and those on the lower arch bar. After rigid fixation of all facial fractures is completed, the MMF can be released, but the arch bars should be kept in place in case training elastics are needed during the healing period. MMF does not correct a malocclusion that is the result of rigid fixation of fragments in suboptimal positions; only replating the fragments corrects such malpositions. MMF may also be needed for management of unfixed fractures, such as subcondylar fractures of the mandible. Some surgeons are no longer placing arch bars when repairing simple mandible fractures. This practice is not yet supported by outcome studies and therefore should be considered controversial.
A number of algorithms have been published regarding the management of frontal, particularly frontal sinus, fractures. Although each has its merits, they tend to be somewhat complicated. Instead, a more simplified approach is presented here. The key issues in frontal sinus trauma relate to two fundamental questions. First, is exploration necessary? Second, is obliteration necessary? The answers require the use of surgical judgment, but certain guidelines are logical.
Keep in mind the purposes of the bone being repaired. The anterior wall needs to be repaired for cosmetic reasons. The posterior wall needs to be managed to protect the anterior cranial fossa. The sinus outflow tracts must function to drain the sinuses, or the sinuses must be obliterated; otherwise chronic infection will result. Thus pure anterior wall fractures that do not extend into the nasofrontal ducts are repaired for cosmetic purposes only. These should be explored if they are significantly depressed, because even in the absence of acute deformity, they are likely to lead to deformities when the swelling resolves. The smallest plates available are generally used, and absorbable plates may also work well in this area, because little or no force demands are made on the repair. Comminuted fragments may be pieced together and “lagged” with single screws to a plate that bridges the defect, or small fragments can be pieced together with small plates and/or wires. Use of the endoscope may allow repair of selected anterior wall fractures with minimal incisions. These techniques are currently in their infancy, and they are likely to become more prevalent as new instruments are developed to simplify the procedures. When the ducts are involved, but the posterior wall is intact, judgment allows more than one option. Frontal sinus obliteration is always acceptable, but it is also reasonable to allow the sinus to function to see what happens. If the sinus becomes obstructed and acute or chronic sinusitis develops, the sinus can be opened endoscopically, or obliteration can be carried out at a later date. In the absence of posterior wall injury, nothing should be lost by this approach, as long as appropriate follow-up of the patient is ensured.
The presence of posterior wall injury complicates the two questions. A nondisplaced posterior wall fracture that does not demand exploration for ductal injury or for anterior wall displacement can be observed. However, if the posterior wall is displaced, it is difficult to determine the status of the dura and u
Source: Cummings Otolaryngology, 6E (2015)