Three‐dimensional motion analysis of facial movement during verbal and nonverbal expressions in healthy subjects

Abstract

Functional impairments of facial expressions alter the quality of life and their quantitative analysis is key to describing and grading facial function and dysfunction. The aim of this investigation was to quantify 3D lip movements in a group of healthy young subjects. Lip movements during five repetitions of common and random sequences of vowels and nonverbal expressions were recorded using an optoelectronic 3D motion analyzer. The mean maximum displacement of facial landmarks was used to compute 3D unilateral mobility and the symmetry indices (SI) separately for each sex. Facial mobility was significantly greater during open-mouth than closed-mouth smiles. Facial movement among the subjects was largest during articulation of the vowel /a/ and smallest for /i/. Lips were pursed with a SI very close to 95%, while smiles were slightly more asymmetric. The vowel /a/ was articulated with significantly greater symmetry than /e/, /i/ and /u/. The outcomes suggest that the proposed method characterized normal facial animations satisfactorily, so it could be a useful tool for assessing patients with facial lesions and dentofacial deformities. Patient assessment would profit from this quantitative approach, which would reduce discrepancies among several clinical examinations. Clin. Anat. 29:991-997, 2016. © 2016 Wiley Periodicals, Inc.

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

“…All patients were analyzed before and after surgery at six, 12 and 24 months follow up with a mimicry evaluation of the whole buccal area following a previously published protocol 25,28,29 .…”

“…For instance, most investigations assessed only nonverbal animations 22,23 , and did not test verbal movements. These last had been reported to be more reliable and reproducible 14,[25][26][27] .…”

“…Soft-tissue facial movements can be noninvasively captured and quantified by 3D motion analyzers 5,14,22,23,[25][26][27][28][29] . Among others, optoelectronic motion systems offer a valuable support for extracting objective measurements by positioning markers in standardized anatomical points 23,[27][28][29][30][31] .…”

“…4 The aim of this longitudinal study is to analyze the pre-surgery versus post-surgery differences in verbal and nonverbal soft-tissue facial movements in a group of patients with dentoskeletal Class III, candidates to bimaxillary orthognathic surgery. We want to establish whether functional symmetry and movement balance of the lower two-thirds of the face changed after surgery, comparing our results to reference values obtained from healthy individuals 25,29 . Our null hypothesis is that bimaxillary orthognathic surgery does not change facial mimicry.…”

Desempenho da mímica facial e qualidade de vida na fase aguda da paralisia facial periférica

“…Nesse âmbito, o crescimento das pesquisas sobre os movimentos faciais contribui para o entendimento, a descrição e classificação da fu nção facial . Estudos com tecnologia atual quantificaram os movimentos faciais tridimensionalmente, com maior precisão (Huffman et al, 1996;Salgado, Curtiss, Tollefson, 2010;Sforza et al, 2010a;Frey et al, 2011;Sidequersky et al, 2016).…”