Tooth-borne distraction of the lower anterior subapical segment for correction of class II malocclusion, subsequent to genioplasty.
BACKGROUND
Alveolar distraction is mainly used to increase height and width of the alveolar crest. This technique, however, is not typically used for lengthening the perimeter of the dental arch or improving teeth axes. We applied alveolar distraction in a tooth-borne manner in the second stage of our original method and obtained favorable results. We therefore present an outline of this method.


METHODS
Genioplasty was first performed to create an infrastructure for sequential advancement of the subapical alveolar segment. After bone union, anterior subapical alveolar osteotomy was performed. The stump of the osteotomized dentate segment was moved forward without changing the incisal edge position, and a box-type bioabsorbable plate with four holes was fixed only onto the dentate segment using two screws. After a latency period, two distraction devices were placed bilaterally to the brackets and activated at 1.0 mm/day. After reaching the desired position, the distractor was immobilized, and then replaced by resin temporary teeth to retain the created space. After the consolidation period, orthodontic treatment was restarted and teeth moved into the newly created space. Bimaxillary surgery was performed after completing pre-surgical orthodontic treatment. Finally, both desirable occlusion and functional masticatory function were obtained.


CONCLUSIONS
This tooth-borne distraction system is one applicable method for patients with skeletal class II and crowding of lower anterior teeth, achieving good results particularly in combination with our original method.
Matsushita
Kazuhiro
K
Department of Oral and Maxillofacial Surgery, Division of Oral Pathobiological Science, Graduate School of Dental Medicine, Hokkaido University, Kita-ku, Sapporo, Hokkaido, Japan. matsushi@den.hokudai.ac.jp
Inoue
Nobuo
N
Yamaguchi
Hiro-o
HO
Ooi
Kazuhiro
K
Totsuka
Yasunori
Y
D020341:Absorbable Implants; D000539:Alveolar Process / Q000601:surgery*; D001860:Bone Plates; D002680:Chin / Q000601:surgery*; D003724:Dental Arch / Q000473:pathology / Q000601:surgery; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007180:Incisor / Q000473:pathology; D008312:Malocclusion, Angle Class II / Q000601:surgery*; D008334:Mandible / Q000473:pathology / Q000601:surgery*; D056948:Orthognathic Surgical Procedures / Q000295:instrumentation / Q000379:methods*; D019857:Osteogenesis, Distraction / Q000295:instrumentation / Q000379:methods*; D010027:Osteotomy / Q000295:instrumentation / Q000379:methods; D019340:Osteotomy, Le Fort / Q000379:methods; D059229:Osteotomy, Sagittal Split Ramus / Q000379:methods; D013027:Space Maintenance, Orthodontic / Q000295:instrumentation; D014087:Tooth Movement Techniques / Q000379:methods