Three-dimensional longitudinal evaluation of facial mimicry in orthognathic class III surgery

Abstract

Order of Authors: federico cullati; francesca m rusconi; andrea mapelli; matteo zago; giada a beltramini; aldo b gianni'; chiarella sforza, MD, PhD Manuscript Region of Origin: ITALY Abstract: The effect of bimaxillary orthognathic surgery on facial mimicry was longitudinally assessed in 15 patients with dentoskeletal Class III facial dysmorphosis (7 men, 8 women, mean age 28 years). The patients were analyzed pre-surgery and 6, 12 and 24 months post-surgery while performing verbal (five vowels) and nonverbal (open and closed mouth smile, lip purse) soft-tissue facial movements. The 3D motions of right and left naso-genian, crista philtri, cheilion and lower lip landmarks were detected by an optoelectronic instrument, and a total mobility index was obtained. Side differences were quantified by an index of symmetry. Patients values were compared to those previously collected in healthy volunteers by computing z-scores. On average, 24 months after surgery no significant differences were found in the mobility of the buccal soft tissues (ANOVA p values range 0.075-0.808), with positive median z-scores (pooled mean value close to 0.6). Symmetry indices ranged around the control reference values, showing no stage-related differences (Friedman test p values range 0.252-0.937), and exceeding 90% for all movements 24 months after surgery. Bimaxillary osteotomy does not compromize facial mimicry, in both verbal and nonverbal facial movements. , which I would like to submit as Research Paper for the publication in the International Journal of Oral and Maxillofacial Surgery.In the paper, we investigated the modifications in facial mimicry after orthognathic surgery using a motion capture instrument. The method of data collection had already been published by the Journal (Facial mimicry after conservative parotidectomy: A three-dimensional optoelectronic study. Int J Oral Maxillofac Surg. 2012;41:986-93; The effect of age and sex on facial mimicry: a threedimensional study in healthy adults. Int J Oral Maxillofac Surg. 2010;39:990-9).

The Effect of Orthognathic Surgery on Soft-Tissue Facial Asymmetry: A Longitudinal Three-Dimensional Analysis

“…The evaluation involved 18 patients with a diagnosis of dentoskeletal Class III facial dysmorphosis, subjected to orthodontics and bimaxillary osteotomy at the Maxillo-Facial Surgery Unit of Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico of Milan, Università degli Studi di Milano). Data about some of the patients were previously published 19 .…”

“…After conventional clinical and radiographic assessments, including posteroanterior, lateral and subchin-vertex projections, all patients underwent a Le Fort I osteotomy and an Obwegeser/Dal Pont bilateral sagittal split osteotomy 19 ; three patients also underwent a genioplasty. Furthermore, all patients had a diagnosis of facial asymmetry based on the clinical evaluation and surgical planning, and needed a compensatory rotation of the jaw and/or the maxilla on the frontal plane (Table 1).…”

“…For surface analysis, optical devices were used, with follow-up times ranging from 6 to 24 months 4,15-18 . Among the others, patients affected by Class III skeletal malocclusion 2,16 , jaws asymmetry 2,3,17 and obstructive sleep apnoea syndrome requiring maxilla-mandible advancement 18 , were investigated; classic anthropometric measurements, evaluations of facial symmetry, and assessments of facial mimicry were performed 2,3,[15][16][17][18][19] .…”

Juvenile Facial Growth and Mimicry: A Preliminary 3D Study

“…This allowed identifying the persistence of unique and characteristic mimic patterns, which were specific of every patient and consistent from childhood to young adulthood. Besides, previous studies postulated that facial surgery and aging have restricted influence on facial mobility in adult subjects .…”

“…Recently, 3D imaging systems have been used, for example, to evaluate facial soft tissues distribution in normal children and in patients after maxillofacial surgery . In this regard, despite the significant changes on the underlying facial bone structures, adult patients have been proven to maintain consistent facial movements before and after maxillo‐mandibular surgery, except for the smile, which amplitude appeared to increase in the majority of cases .…”