Authors of section


Ricardo Cienfuegos, Carl-Peter Cornelius, Edward Ellis III, George Kushner

Executive Editors

Marcelo Figari, Gregorio Sánchez Aniceto

General Editor

Daniel Buchbinder

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Closed treatment (MMF)

1. Treatment

Arch bars are applied to the teeth and MMF is secured. The patient is monitored using x-rays for positional changes of the mandibular ramus. At 6 weeks MMF is released and fracture stability determined by manipulation. The patient is placed on a soft diet and if the occlusion maintains for a two-week period, the arch bars may be removed.

Biomechanics of the mandible.

Closed treatment of symphyseal fractures

2. Case example


Panoramic and PA view of a minimally displaced comminuted symphyseal/body fracture in an adolescent patient.

Note: treatment of a simple or a basal triangle fracture would be no different.

Closed treatment of symphyseal fractures

Pretreatment occlusal relationship
A malocclusion is the result of this minimally displaced comminuted symphysis/body fracture.

Closed treatment of symphyseal fractures.


Closed treatment was selected for this patient mandibulomaxillary fixation (MMF) because the extended area of comminution would have required a large reconstruction plate being placed.

Closed treatment of symphyseal fractures

The patient did not object to a course of MMF and did not want a larger operation.

Closed treatment of symphyseal fractures

Postoperative x-rays

"Postoperative" x-rays following closed treatment and MMF show good alignment of bone fragments and reestablishment of occlusion.

Closed treatment of symphyseal fractures

3. Aftercare following closed treatment of mandibular fractures

The patient should be instructed how to release the MMF in case of emergency. Some surgeons prefer to provide wire cutters to the patient for the period of MMF. During this period, wire fatigue and loosening can occur. The patient should report any loosening of the MMF to the surgeon immediately.

As an alternative, the MMF may be achieved by using elastics instead of wires. With an adequate number of elastics, the same level of reliability can be reached minimizing the risk of accidents during an emergency situation.

Postoperative x-rays are taken within the first days after surgery. In an uneventful course, follow-up x-rays are taken prior to releasing the MMF.

It will be necessary to see the patient approximately 1 week postoperatively to assess the stability of the occlusion and to check for infection of the surgical wound. The intermaxillary fixation wires or elastics must be assessed and proven to hold the patient tightly in occlusion. Patients also have to be periodically re-examined to rule out signs of infection. At each visit, the surgeon must evaluate patientability to perform adequate oral cleaning. It may be necessary to provide additional instruction to assure appropriate hygiene and wound care.

Adequate dental care is required in most patients having suffered a mandibular fracture.

There should be no malocclusion detected as occlusion is determined and secured in the operating room.

On releasing the MMF, physiotherapy can be prescribed. The mandible will be hypomobile after the period of MMF, and the muscles will be atrophic and “tight.” Opening and excursive exercises should be demonstrated and implemented. Goals should be set, and typically, 40 mm of maximum interincisal mouth opening should be attained by 4 weeks postoperatively. If the patient cannot fully open his mouth, additional passive physical therapy may be required such as Therabite or tongue-blade training.

MMF renders eating, speaking and oral hygiene more difficult. Patients will therefore have to follow three basic instructions:

1. Diet
The diet has to be in a liquid or semi-liquid form. For patients with a full complement of teeth, the diet must be more liquefied than when there are gaps with teeth missing. Because the diet will be no-chew, more fluids are required to assist in swallowing the food. A blender, or preferably, a juicer is useful. Anything can be made into a liquid or semi-liquid form with these tools. Liquid dietary supplements from the grocery store help maintain caloric intake. The patient should monitor their body weight on a weekly basis during the period of MMF to evaluate any dramatic changes.

2. Oral hygiene
Patients must be instructed in oral hygiene procedures. The presence of the arch-bars and MMF wires makes this a much more difficult procedure, and the inside of the teeth cannot be reached with a toothbrush. A soft toothbrush (dipping in warm water makes softer) should be used to clean the buccal/labial surfaces of the teeth, arch-bars and wires. Chlorhexidine oral rinses should be prescribed and used at least 3 times each day to help sanitize the mouth. The tongue can be used to swipe the lingual surfaces of the teeth. With larger debris, a 1:1 mixture of hydrogen peroxide/chlorhexidine can be used. The bubbling action of the hydrogen peroxide helps remove debris. A Waterpik® is a very useful tool to help remove debris from the wires.

3. Speech
Patients are told to speak as freely as possible. Over the course of 1–2 weeks, patients can usually speak quite intelligibly, although voice projection remains difficult during the period of MMF.