[Surgical expansion of midpalatal suture by means of modified Le Fort I osteotomy]

From 1984 to 1987 thirty-nine adult patients suffering from a transverse maxillary deficiency were operated by a modified Le-Fort-I-osteotomy to facilitate the following rapid orthopedic expansion. A horizontal osteotomy was made through the lateral wall of the maxilla from the interior lateral aspect of the piriform aperture to the pterygomaxillary suture, which was also sectioned. After the operation the palatal expansion appliance (Biedermann-Hyrax-screw) was normally activated one one-quarter turn twice a day until the desired expansion was achieved. In each case this surgical orthodontic procedure showed to be an excellent method to correct transverse maxillary deficiencies. This procedure is especially indicated in patients with bilateral crossbite. Unilateral crossbites can also be treated this way, if a later Le-Fort-I-osteotomy is necessary to correct sagittal or vertical discrepancies.