Quantitative evaluation of lip symmetry in functional asymmetry

摘要: SUMMARY The objectives of this study were to quantitate lip symmetry/asymmetry from clinical photographs; demonstrate that asymmetry due functional side shifts (functional asymmetry) leading unilateral crossbites including the canines, results measurable thinning upper and thickening lower on crossbite when viewed in intercuspal contact position; show orthodontic treatment aimed at eliminating shift would achieve symmetry, both visually quantitatively. consisted 26 patients, who divided into two groups: a group 13 patients (eight females, five males, aged 8‐17 years) with asymmetry, control age- gender-matched subjects other forms malocclusion without asymmetry. All exhibited canines position. Digitized images frontal facial photographs analysed for symmetry pre- post-orthodontic treatment. lips subdivided four quadrants surface area length each quadrant measured expressed as percentage total area/length relevant lip. degree was obtained by calculating difference or between In group, enlarged while contralateral reduced (mean ratio 59.9 40.1 per cent, mean 53.0 47.0 cent). demonstrated differences smaller inverse. controls showed small right left sides (less than 1 After treatment, groups displayed visual quantitative i.e. an approximately 50 cent quadrant. absolute values, had up 3 regardless 9.2 19.8 Asymmetry values post-treatment. all 2 6.3 8.6 post-treatment cent. Although could be quantitated using parameters (lip length), parameter proved more sensitive tool measuring