The treatment of bimaxillary protrusion. A cephalometric consideration of changes in the inter-incisal angle and soft tissue profile.

Thirty bimaxillary protrusion cases, who had four first premolars extracted were compared with thirty Class I malocclusion cases who, likewise, had similar extractions and treatment. The changes, both in incisor relationships and the concurrent soft tissue profiles are documented. During treatment, the inter-incisal angle was increased by 20 degrees and relapsed by 4 degrees post-treatment. The protuberance of the soft tissue profile was significantly reduced by 4 degrees concurrently (Holdaway Angle). It is concluded that worthwhile treatment objectives can be achieved in these cases.