IMF is necessary after open reduction of mandibular fractures (monocortical titanium miniplates) because it allows a three-dimensional dynamic control of the reduction and the occlusal restoring (varyng and optimizing the vectors of the traction "à la dèmande" ) with a good bone restructuring. IMF (also referred to as maxillo-mandibular fixation, or MMF) is a commonly applied, fundamental technique of wiring the jaws together in trauma and reconstruction procedures. The IMF screw offers the advantage of a self-drilling tip and easily identified wire holes that will provide a simple and quick method for achieving intermaxillary fixation in simple fractures. Generally, between two and- four screws are placed into each mandible and maxilla and then connected and tensioned with wire to establish and maintain occlusion. In more complex cases we resort to arch bar. We never use rigid IMF by using metallic wires but elastics. IMF is maintained during six weeks. (https://www2.aofoundation.org/wps/portal)

IMF is not necessary after ORIF mandibular fracture if the occlusion is correctly restored. Functional adaptation is better with mobilisation and healing is more rapid. There is also less riak of long term restriction of mouth opening. IMF screws have significant risks of dental injury, do not reproduce 3 dimensional occlusion and alternatives should be sought. IMF for 6 weeks significantly compromises function for a longer period than mobilisation, but the patient needs to be observed to ensure occlusion is maintained.

Condylar fractures should be managed differently and often a 2 week period of IMF after ORIF will aid with the post-operative masseteric pain.

i agree with Andrew,if ORIF is done correctly then there is no need of imf,In my practice i seldom use IMF,even in subcondylar fractures

It depens on location of fracture, favorable or unfavorable. In favorable fracture, there is no need to apply IMF but communited unfavorable fracture need IMF

IMF (intermaxillary fixation) after ORIF (open reduction and internal fixation ) is rarely used nowadays. However, in difficult situations where it is impossible to get a satisfactory occlusion with ORIF, I may use IMF for four to six weeks an adjutant to get a better occlusion. This happens with severe comminuted fractures.

I do not use IMF or MMF screws as they do not really give a good occlusion intraoperatively. My assistant will hold the mandible in occlusion while I plate it. I agree entirely with Andrew Sidebottom.

If I use IMF then I will use archbars as I can use elastics to change the vector as well.

In summary there is no place for IMF post surgery for routine mandibular fracture management.

This is a very controvesial topic. Some Surgeons use IMF for 3 weeks after ORIF of mandibular fractures. Others, including me, do not use IMF after ORIF with monocortical plates except when there is a subcondylar fracture managed by closed reduction, where arch bars and elastics are used.

The argument for using IMF in patient managed with monocortical plate is that some patient may start eating hard food early after ORIF, which may lead to bending of the plates, displacement of fracture and malocclusion. The argument for not using IMF is that you want early return to function.