Three-dimensional analysis of nasolabial soft tissues while smiling using stereophotogrammetry (3dMDTM)

The nasolabial region is the central esthetic unit of the face and is considered one of the most important determinants of the facial esthetic. The facial morphometry of soft tissues is a very important tool in facial surgery. Advances have been made recently in the capture and analysis of 3D images, which offer great development potential in the diagnosis and treatment of facial deformities. The aim of this study was to characterize the nasolabial region of patient candidates for orthognathic surgery using 3D facial captures. A study was conducted to characterize the width of the nasal base and the nasolabial angle in adult patients through 3D photographs. 30 subjects were included, taking two 3D photos each, one in a resting position and the other smiling. The three-dimensional capture was done with the 3dMDface System. The measurements were taken with the 3dMD Vultus software. The length of the alar base was an average of 34.3 ± 2.6 mm at rest, and 39.1 ± 2.9 mm smiling. The mean of the nasolabial angle was 104.6 ± 9.6° at rest and 105.4 ± 14.3º smiling. Additionally, the distance of the alar base smiling compared to its distance at rest increased an average of 4.83 mm, whereas the nasolabial angle smiling increased an average of 0.8º compared to at rest. In this study, the nasolabial angle did not present any significant changes so that its assessments in the case of facial modifications can be standard; the width of the nasal base is significantly modified with the smile and thus a more intense study of any type of modification in this area is required.