We read with interest the recently published paper by Ma et al. in which they reported the use of transpalatal screw traction for sagittal fractures of the palate and maxilla. The technique appears to be a modification of the well-known intermolar wiring in terms of anchorage. Sagittal or parasagittal fractures of the palate, as described, are characterized by posterior widening of the maxillary dental arch, and can be controlled easily using a simple intermolar wiring technique. We routinely use this technique by simply positioning the intermolar wire, then approximating the jaws and placing intermaxillary fixation (IMF) wires, but keeping them loose. The intermolar wire is then tightened (depending upon the increased width of the posterior maxilla) by directly visualizing the molar occlusion, followed by tightening of the IMF wires.
This popular technique allows for examination of the occlusion at the same time, i.e. while tightening the wires, which is not possible in the case of transpalatal screw traction. Moreover the intermolar wiring technique is more simple, cost-effective, and versatile, and may be performed rapidly in the emergency situation to stabilize sagittal palatal fractures without the need for any extra equipment. This is particularly useful in the resource-limited settings of developing countries.
In addition, the transpalatal screw traction technique carries a risk of damage to the molar roots, requires anaesthesia for removal, is less effective, and is cumbersome because of the comparative inaccessibility. During reduction, the sagittally fractured palate or maxilla will behave as a third-order lever similar to tweezers or tissue-holding forceps. The moment arm ( Fig. 1 , label a) will be larger in the intermolar wiring situation than in transpalatal screw traction ( Fig. 1 , label b), resulting in more torque production in the former case ( Fig. 1 , label E). The physical basis of the torque generated in each case is depicted in Fig. 1 .
