Correlation between vertical hard and soft tissue variables of the face
Dr. Hoseinzadeh-Nik T.,1 Dr. Yazdani-Damavandi L.,2 Dr. Gholami-Borujeni D.3
1 Associate Professor, Department of Orthodontics, Faculty of Dentistry, Tehran University / Medical Sciences. Tehran, Iran. 2 Resident, Specialty Program, Department of Operative Dentistry, Faculty of Dentistry, Hamedan University of Medical Sciences. Hamedan, Iran. 3 Resident, Specialty Program, Department of Orthodontics, Faculty of Dentistry, Tehran University / Medical Sciences. Tehran, Iran.
(Received 18 Sept, 2008 Accepted 2 Feb, 2009)
Background & Aim: Facial vertical variables are important components of soft tissue analysis which are used in clinical esthetic evaluation. The purpose of this study was to evaluate the correlation between vertical skeletal and dental variables of hard and soft tissues of human face.
Materials & Methods: A total of 46 patients (23 boys and girls) were included in this cross-sectional study. Selected angles and facial dimensions were measured during the clinical appointments. For facial proportions, from frontal view, selected reference points were marked on the face. The accuracy of this work was validated by an orthodontist. Hard tissue variables were also measured using patients’ lateral cephalograms. Finally, the correlations between soft and hard tissue variables were evaluated using correlation and regression analysis.
Results: The statistical analysis showed correlations between number of vertical soft and hard tissue variables, with linear relationship among some of them. Significant correlation was detected between nasolabial angle of soft tissue and hard tissue N-Pog, N-B, N-A, N-Me and Lower incisor to Mandibular plane (P=0.014, P=0.013, P=0.046, P=0.015, P=0.037 respectively). Also, significant correlation was detected between soft tissue N-Me and hard tissue N-Me, and N-Pog between soft tissue supraorbital ridge to subnasal and hard tissue N-A, and between soft tissue subnasal to menton and hard tissue A-Me and A-B (P=0.000 in all cases). The highest correlation was observed between soft tissue subnasal to menton and hard tissue A-Me (R=0.738).
Conclusion: Given the results of this study, it can be concluded that some clinical parameters in vertical dimension, of facial hard tissue variables can be replaced by soft tissue counterparts in order to design the diagnosis and treatment plan according to soft tissue variable measurements.
Key words: Cephalometry - Vertical variables - Hard tissue - Soft tissue - Correlation.
Corresponding Author: Dr. Hoseinzadeh-Nik T., Associate Professor, Department of Orthodontics, Faculty of Dentistry, Tehran University / Medical Sciences. Tehran, Iran.