Correlation between the incisors axis inclination and the exposure of the vermilion. E Candida, S Summa, I D’Apolito, C Strappa, R Deli.
Date: April 2017.
Source: XXIV Congresso Nazionale Collegio dei Docenti Universitari di Discipline Odontostomatologiche, Milano, Italy.
Objective: the enhancement of the lips through cosmetic techniques is a popular procedure. In literature there are not many studies which demonstrate all the aspects that influence this area which is so important for patients. Orthodontic biomechanics related to the incisors axis correction can change the patient aesthetic perception in this area of the face. The aim of this study is to investigate the possible correlation between the incisors’ axis and the exposure of the vermilion area.
Methods: For this study, 26 patients aged 8-11 years old have been selected from the Orthodontic Department of the Policlinico Gemelli in Rome. The selection criterion of the study was the presence of an overjet between 0 and 12 mm. Three-dimensional images were acquired with a stereophotogrammetric technique (3dMD. Atlanta, Ga). From selected images, it was possible to calculate the areas of the upper lip and lower lip of each patient through a Geomagic Control software. The incisors inclination was measured on latero-lateral teleradiography through the Illinois analysis: the upper incisor axis inclination compared to the SN line (Sella – Nasion) and the lower incisor axis inclination compared to the ML line (Mandibular Line) have thus been measured. Two multiple linear regressions were performed by a SPSS software. The first regression examined as a dependent variable the upper lip areas and as an independent or predictor variable the inclination of the incisors’ axis and the dental overjet. The second regression examined as a dependent variable the lower lip areas and as an independent the same variable of the first regression.
Results: Our statistical analysis through software showed that there isn’t any correlation between the dental overjet and the appearance of the vermilion area; this is because even 0 is included inside the confidence interval (95%) of B coefficients not
standardized from the incisors axis.
Conclusions: From the results obtained it was possible to highlight a possible orthodontics’ limit in improving the exposure of vermilion. There is not a statistically significant correlation between teeth and lips position. This result suggests a possible limit of orthodontic treatment to improve the exposure of vermilion, which may have been influenced by the low number of samples examined. Prospective studies should then increase the number of patients in order to investigate better the relationship between the orthodontic
treatment and the exposure of the vermillion area.
Article: Correlation between the incisors axis inclination and the exposure of the vermilion.
Authors: E Candida, S Summa, I D’Apolito, C Strappa, R Deli, Catholic University of Sacred Heart, Rome, Italy.