title: Gender differences in the amount of gingival display during smiling using two intraoral dental biometric measurements.
abstract: OBJECTIVE
  The aims of this study were to compare gender differences in the width and length of the maxillary right central incisor and the horizontal and vertical overlap of the anterior teeth and to determine the relationships of these two intraoral dental biometric measurements with the amount of gingival display during smiling.
  
  
  METHODS
  A total of 61 men and 66 women were included in this study. For each participant, the gingival tissue display during smiling was judged to be either visible or not, and the maximum mesiodistal and incisogingival dimensions of the maxillary right central incisor were measured, along with the amount of horizontal and vertical overlap of anterior teeth using a digital caliper. Gender differences in these parameters and the relationship between subjects showing gingival display when smiling and the two intraoral dental biometric measurements were determined. Statistical analyses of data were performed using SPSS (V11) software. The mean scores for gender were calculated, and a Student's t-test was used to identify significant differences between both groups. Significance level was set to 0.05.
  
  
  RESULTS
  The age of the participants ranged between 23 and 52, with a mean of 33.47 +/- 9.07 years. A relatively small percentage of the subjects (22.05%) displayed gingiva when smiling. More women displayed gingiva when smiling than men, with a 2:1 female:male ratio. Men exhibited significantly (p < 0.05) wider (8.76 +/- 0.66 mm) and longer (10.28 +/- 0.88 mm) central incisors compared to women (7.92 +/- 0.72 mm; 9.27 +/- 0.93 mm width and length, respectively). No gender differences were found in the width-to-length ratio. Subjects with gingival display had significantly more horizontal (4.28 +/- 1.21 mm; p < 0.001), and vertical (3.52 +/- 0.66 mm; p < 0.05) overlap of anterior teeth compared to those who did not display gingiva when smiling (2.40 +/- 1.03 and 2.30 +/- 0.93 mm, respectively).
  
  
  CONCLUSIONS
  Significantly more women displayed gingiva in smiling. Men had significantly wider and longer central incisors. No differences were recorded between men and women relative to both the horizontal and vertical anterior tooth overlap. Subjects who displayed gingiva when smiling had more horizontal and vertical overlap of anterior teeth.
authors.affiliation: Division of Dentistry, Marka Medical Center, Princess Aysha Bint Al-Hussien Medical Complex, Amman, Jordan. osamajabrah@hotmail.com
authors.forename: Osama
authors.initials: O
authors.lastname: Al-Jabrah
authors.forename: Raghda
authors.initials: R
authors.lastname: Al-Shammout
authors.forename: Waddah
authors.initials: W
authors.lastname: El-Naji
authors.forename: Mahasen
authors.initials: M
authors.lastname: Al-Ajarmeh
authors.forename: Abdel-Hakeem
authors.initials: AH
authors.lastname: Al-Quran
mesh_terms: D000328:Adult; D000367:Age Factors; D004955:Esthetics, Dental; D005260:Female; D005881:Gingiva / Q000033:anatomy & histology*; D006801:Humans; D007180:Incisor / Q000033:anatomy & histology*; D007597:Jordan; D008297:Male; D008437:Maxilla; D008875:Middle Aged; D009811:Odontometry / Q000379:methods; D012737:Sex Factors; D012904:Smiling; D019228:Tooth Crown / Q000033:anatomy & histology*; D055815:Young Adult