Relationship between the Position of the Incisors and the Thickness of the Soft Tissues in the Upper Jaw: Cephalometric Evaluation

Aim: The aim of this study is to verify if the thickness of soft tissues and inclination of the incisors have some relation with profile, to analyze its relevance considering these two parameters separately and to screen how the combination of different inclinations and different thickness can generate different facial patterns. Materials and methods:The study was performed on 47 Caucasian patients aged between 6 years and 16 years of divided into 24 males and 23 females.None of the patients presented craniofacial changes of syndromic nature.All patients presented a value of SNA in between 80° and 84°.The inclination of the upper incisor related to the bispinal plane was between 104° and 116°.Each radiograph has been digitized or analyzed directly in digital format.To analyze the relationships between soft tissues and position of the incisors using various cephalometric measures and statistical methodology were used.Results: Analysing the general correlation between all the cephalometric parameters considered, the results found show that the thickness of the tissues had an effect in modifying the aesthetic profile with respect to the position of the incisors.The cephalometric parameters related to the esthetic profile of the maxilla are all linked by strong correlations, especially correlation between SU, ULA and LS were very high.The differences between the means were statistically significant for different groups.Using the values of Mx1 and thickness of the lip as independent variables, while the LS, SU, ULA and NLA values as dependent variables all results are significant with respect to the prediction p < 0.05.Conclusion: Thickness of the soft tissues showed a significant influence on the profile with respect to the position of the incisors.Clinical significance: Data obtained highlighted that thickness of the soft tissues must be taken into account before starting an orthodontic treatment in order to obtain best aesthetic results.