Impact of genioplasty on mandibular growth during puberty

Genioplasty has been validated for the correction of mandibular vertical excess and is generally performed at the end of the growth period, either alone or in association with other forms of osteotomy. Our aim was to assess whether genioplasty performed at an earlier age can impact mandibular growth.

This comparative prospective study included 25 high-angle, mouth-breathing adolescents following orthodontic and ENT treatment. Subjects were divided into two groups according to their stage of puberty, either early (group 1: Tanner's stage 3, n=12) or late stage (group 2: Tanner stage 4-5, n=13). Genioplasty was performed in both groups. Cephalometric comparison was made on the overall population and for each group, before and after genioplasty (at 1, 6, 12 and 18months).

In the immediate postoperative period, significant variation of all the cephalometric measures was observed within each group showing reduction of the vertical dimension and sagittal augmentation. Eighteen months post-surgery, only group 1 exhibited a significant increase in SNPog. Augmentation of the SNB and anterior mandibular rotation were also significantly greater in group 1. The difference in the direction of growth of the mandible before genioplasty (18months of orthodontics) and postgenioplasty (18months of postoperative monitoring) was also significant.

Early genioplasty permits redirection of mandibular growth conducive to orthopedic correction of high angle Class II.