Aesthetic preferences of the nasolabial angle: A three-dimensional (3D) study

Historically, the ideal nasolabial angle (NLA) ranges from 90° to 120°. This study was conducted to evaluate the current preferences of NLA of laypeople and clinicians based on 3D female textured and 3D male textured images. Three-dimensional software (Di3DView) was used to create a 3D facial image with a NLA of 70°. The colour images of one male and female adult were remapped onto the generated 3D image, resulting in a colour textured 3D male, and 3D female image, both with the same facial shape and a 70° NLA. This process was repeated for NLA's of 80°, 90°, 100°, and 110°. Based on a 7-point Likert scale, seventy-two laypeople and fifty clinicians were asked to evaluate the NLA of each rotating 3D image and give a facial attractiveness score. Clinicians and laypeople showed good intra-rater reliability (ICC 0.75 to 0.89). A 90° NLA was found to be most attractive for 3D male textured images (p=0.001). Whilst for 3D female textured images, an 80° and 90° NLA was found to be the most attractive (p=0.001). Laypeople were more critical than clinicians. Both groups would seek treatment for NLA of 70°, 100°, and 110°. We were able to show that 90° NLA's were preferred for males and 80°-90° NLA's for females. Laypeople were more critical of obtuse nasolabial angles, and less critical of acute nasolabial angles than clinicians. Obtuse NLA's angles greater than 90° are no longer considered acceptable.