To evaluate lower facial profile in females in different skeletal patterns.

Investigation pictures of three females with beautiful lower facial profiles from Department of Orthodontics, Henan Stomatological Hospital were collected. The skeletal patterns of these females were classified as average, low and high angle, respectively.Upper lip process point (UL) was moved backwards horizontally to reach towards the E line and go even further gradually in above pictures. The distance changed according to E line was defined as DE value. If UL was in front of E line,DE value was denoted as positive, or else negative. Collectively, we obtained 30 pictures (10 pictures in each skeletal facial type) with different DE values (-5, -4, -3, -2, -1, 0, 1, 2, 3, 4 mm), which were divided into average, low and high angle group according to the skeletal facial type. The pictures were evaluated by 144 randomly-selected adult orthodontic patients [66 males, 78 females, aged (29.4±7.7) years] who visited Department of Orthodontics, Henan Stomatological Hospital from June to September, 2019 and 138 orthodontists (including qualified orthodontists and postgraduate orthodontic students [60 males, 78 females, aged (32.2±7.1) years] who participated orthodontics conferences in Henan Stomatological Hospital in June, 2019. The acceptance rate was calculated and rate above 60% was deemed as acceptable DE range. Evaluators were also asked to choose the most esthetic profiles for the best DE value in each skeletal facial type.Data discrepancy was analyzed using Kruskal-Wallis analysis andchi-square test.

Most accepted DE was -2 mm among total investigators including orthodonticpatients and orthodontists. There was no difference in total acceptance rate between orthodontists and patients (P>0.05). There was statistic difference in total acceptance rate in different skeletal patterns between orthodontic patients and orthodontists (P<0.05). In total investigators, total acceptance rate was 62.1% (1 752/2 820) in average angle group, 55.4%(1 563/2 820) in high angle group and 33.5%(946/2 820) in low angle group, respectively. Acceptable DE range in three facial types was -4~2 mm (average angle), -2~2 mm (high angle) and -2~-1 mm (low angle), respectively.

According to the evaluation of both orthodontic patients and orthodontists, the best DE was-2 mm.Total acceptance rate and acceptable DE range ranked first in average angle group, second in high angle group and third in low angle group.

Orthodontics; Data collection; Profile aesthetics; Skeletal facial types