Chin shield osteotomy--a new genioplasty technique avoiding a deep mento-labial fold in order to increase the labial competence.

The authors report a genioplasty technique in which the advancement of an anterior mandibular segment is executed with a specific osteotomy form that helps to avoid a deep mentolabial fold and improves labial competence. The osteotomy presented achieves this by creating a 'chin shield' where the mandibular segment advanced is relatively high on the side of the buccal cortex and lower on the lingual side and where the osteotomy or down-fracture in between is in an oblique angle in the sagittal plane.