A Research On The Effect Of Chin Position And The Inclination Of Lower Incisor To Facial Profile Attractiveness

ObjectiveInvestigate the effect of chin position and the inclination of lower incisors to the facial profile attractiveness with silhouettes and photochromes.Changing the chin position and the inclination of lower incisors respectively or simultaneously,try to conclude their respective and mutual effects.Study the differences between silhouette and photochrome on facial profile attractiveness.MethodsExperiment 1:1.Subjects:A female volunteer knows about the test was selected.Take a photo for the volunteer on the natural head posture through Canon digital camera.Take a cephalometric film through ORTHOPHOS XG 3D ready Ceph Dental X-ray Machine.2.Images dispose(1)Input the cephalometric film and profile photo of the volunteer to the Dolphin Imaging 11.8 program and simulate the inclination of lower incisors changes from-12°to +12°(4° per picture)to generate the series A.(2)Edit the profile photo of the volunteer through Dolphin Imaging 11.8 program,change the soft tissue pogonion in the sagittal direction from-6 to +6 mm(2 mm per picture)to generate the series B.(3)On the picture B3(the soft tissue pogonion 2 mm backwards),simulate the inclination of lower incisors changes from-12°to +12°(4°per picture)to generate the series C.(4)On the picture B5(the soft tissue pogonion 2 mm forward),simulate the inclination of lower incisors modificates from-12°to +12°(4°per picture)to generate the series D.Above all,there are 28 pictures.Turn the photochromes into silhouettes through Photoshop program.A4 and B4,B3 and C4,B5 and D4 are the same respectively.Keep the A4 and B4,B3 and C4 for reliability analysis and remove D4 from the research.3.raters selectionThere are 3 groups of raters:orthodontic patients,laypeople and orthodontists.4.rank the silhouettesFirstly let the raters devide the silhouettes into three groups according to their feeling to the beauty of the silhouettes.Secondly rank the silhouettes through most beautiful to least.Then mark the ranks of each silhouette.Add the ranks of silhouettes in different groups,calculate the mean ranks of each silhouettes from different groups.5.statistic analysisSPSS20.0 software is used to compared the mean ranks of different silhouettes and the difference between groups.Analyse the possible elements which influence the ranks of silhouettes.Experiment 2:The process is almost the same as experiment 1 except that the ranked pictures are photochromes.Results1.The inclination of lower incisors change from-12° to +12° does not influent the profile attractiveness obviously.2.In all the groups,the profile with a normal chin position or 2 mm protruded is most favored.3.With the chin 2 mm retracted,the attractiveness of photochromes from all groups increase when the inclination of lower incisors increase.With the chin 2 mm protruded,the inclination of lower incisors change from-12° to +12° does not influent the profile attractiveness obviously.4.Females prefer the profile with 2 mm protruded chin than males.The profile with a retracted chin is more acceptable by males.The orthodontists prefer the profile with 2 mm protruded chin than patients and laypeople.The profile with 2 mm protruded chin is more preferred in silhouettes than photochromes.Conclusion1.It doesn't influent the profile attractiveness of patients with normal or slightly protruded chin position through changing the inclination of lower incisors.2.When the chin is slightly retracted,increase the inclinations of lower incisors can improve the profile attractiveness in a certain range.3.There are differences between orthodontists and others about profile aesthetics.