If I've understood it, "LeFort 1 osteotomy" is actually the name given to several surgical procedures in which only the tooth-bearing part of the mid-face is separated from the supporting structures and repositioned upwards, downwards, forwards or backwards.






This page describes it pretty well (and the second diagram above comes courtesy of the same page)

The term "segmental Lefort 1 osteotomy" describes a procedure similar to the above, but in which the maxilla is not only moved, but is also cut into two or three pieces. Now I think (and of course I may be wrong) that in one way of doing this the maxilla is separated into two parts such as to allow widening or the upper jaw. It's kinda "instant expansion". Check out this thread started by smile, as this is one of the procedures she had, as did smile2006 - take a look at this thread for her early post-op experiences.


"Mandibular osteotomy" simply means a surgery on the lower jaw bone. I think the most common are the BSSO (bilateral sagittal split osteotomy) which can be used either to advance the mandible (for Class II cases), or set it back futher (for Class III i.e. underbites) and the genioplasty (to move the chin forward or back). But other mandibular osteotomies are carried out.

a) Mandibular Sagittal Split Osteotomy

The back of the lower jaw is split bilaterally under general anaesthetic in the region of the wisdom teeth, which are generally removed in a separate operation at least 6 months prior to corrective surgery.

The procedure is carried out in about 1.5 hours and permits the lower jaw to be advanced or pushed back with adequate bone contact for healing.

The bone is fixed in its new position by screws which are inserted through tiny external skin incisions which are located at the angle of the jaw. These heal with minimal external scarring.