Mandibular prognathism is defined by John Hunter as follows : "The lower jaw projecting too far forwards so that the foreteeth pass before those of upper jaw, therefore disfigurement and malocclusion are the two fo facial main characteristics." Other distinguishing features are
the coexistence of class 2 malocclusion, incomplete closure of lip, deviation of the midline, and decrease of labiomental fold. Generally the functional occlusal relationship and balanced facial harmony cannot be obtained by surgical or orthodontic treatment alone and its success depends on careful conjoint, supplementary diagnostic and treatment plannings.
As a cardinal principle we made the following combined surgical and orthodontic treatment schemes
1) orthodontic treatment relocates and decompenstaes the malpositioned teeth and therefore skeletal deformity is exposed maximally.
2) surgical treatment eliminates the maximally exposed skeletal defect, therefore the dramatic facial balance and functional occlusal relationship is obtained.
Treatment planning includes the pre- and post-operative orthodontic treatment, lateral cephalometric prediction tracing (LCPD) and model surgery with dental cast.
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