Photogrammetric Analysis of Attractiveness in Indian Faces.

BACKGROUND: The objective of this study was to assess the attractive facial features of the Indian population. We tried to evaluate subjective ratings of facial attractiveness and identify which facial aesthetic subunits were important for facial attractiveness. METHODS: A cross-sectional study was conducted of 150 samples (referred to as candidates). Frontal photographs were analyzed. An orthodontist, a prosthodontist, an oral surgeon, a dentist, an artist, a photographer and two laymen (estimators) subjectively evaluated candidates' faces using visual analog scale (VAS) scores. As an objective method for facial analysis, we used balanced angular proportional analysis (BAPA). Using SAS 10.1 (SAS Institute Inc.), the Turkey's studentized range test and Pearson correlation analysis were performed to detect between-group differences in VAS scores (Experiment 1), to identify correlations between VAS scores and BAPA scores (Experiment 2), and to analyze the characteristic features of facial attractiveness and gender differences (Experiment 3); the significance level was set at P=0.05. RESULTS: Experiment 1 revealed some differences in VAS scores according to professional characteristics. In Experiment 2, BAPA scores were found to behave similarly to subjective ratings of facial beauty, but showed a relatively weak correlation coefficient with the VAS scores. Experiment 3 found that the decisive factors for facial attractiveness were different for men and women. Composite images of attractive Indian male and female faces were constructed. CONCLUSIONS: Our photogrammetric study, statistical analysis, and average composite faces of an Indian population provide valuable information about subjective perceptions of facial beauty and attractive facial structures in the Indian population.

Smile analysis in different facial patterns and its correlation with underlying hard tissues.

BACKGROUND: The subject's inherent growth pattern can be an effective factor in characteristics of smile. More vertical growth in the posterior maxilla than in the anterior maxilla could result in a changed relationship between the occlusal plane and the curvature of the lower lip upon smile. In order to broaden the understanding of how smile gets affected by growth pattern and the underlying hard tissues, the present study was undertaken to compare smile in various growth patterns, to determine sexual dimorphism, if any; as well as to correlate smile with underlying hard tissues. METHODS: One hundred and fifty subjects were selected amongst the students in the Dental Institute and from the outpatient department of Department Orthodontics and Dentofacial Orthopedics. Sample selected for the study ranged in the age group of 17 to 25 years. Selected individuals were subjected to lateral head cephalometric radiography in the Department of Oral Medicine and Radiology and videography. Cephalograms were traced and the subjects were divided into horizontal, average, and vertical growth pattern on the basis of GoGn-SN, lower anterior facial height, and Jaraback's ratio. The video clip was downloaded to obtain frame of posed smile. Cephalometric and photographic measurements were recorded and subjected to statistical analysis. RESULTS: The mean values of smile parameters were significantly higher in males as compared to females irrespective of the growth pattern. The mean incisal display, interlabial gap, lower lip to incisal edge distance, upper vertical lip length, and occlusal plane angle was highest in both males and females of vertical facial growth pattern group; whereas, the smile index, posterior corridor (left and right) were less in vertical facial growth pattern group in both males and females. Thus, the parameters in vertical dimension were increased in vertical growers whereas, the parameters in transverse dimension decreased. CONCLUSIONS: The facial growth pattern has significant influence on the parameters of smile along with definite sexual dimorphism. The angular and linear parameters, except saddle angle and lower incisor to NB (linear and angular), influenced smile.

Maturation of permanent teeth in different facial types: a comparative study.

BACKGROUND: Accurate diagnosis of dental maturation help in diagnosis, treatment planning, and timing in orthodontics and dentofacial orthopedics. AIM AND OBJECTIVE: The present study is undertaken to compare and correlate chronological age and dental age of patients with average, vertical, and horizontal facial types, and to find out any sex difference in dental age in different growth patterns and to evaluated the reliability of Willem's method in Indian population. MATERIALS AND METHODS: Subjects in the age group of 8-10 years were screened from Out Patients Department of Orthodontics and Dentofacial Orthopedics and from the various school of the City, were subjected to cephalometric radiography and orthopentomograms. Angular and linear measurements used included;-SN Go-Gn angle, J.R. (Jarabak ratio) and LAFH (lower anterior facial height), to group total sample of 150 children. Group 1 (average grower), Group 2 (vertical grower), and Group 3 (horizontal grower). Then dental age for each child in different group was calculated from OPG of each subject and compared with chronological age using Student t-test. RESULTS: The results suggest a difference in dental age in subject with vertical and horizontal growers. Vertical grower showed earlier maturation compared to horizontal growth patterns. There was insignificant difference present when vertical grower and horizontal grower were compared with average growth pattern. Insignificant difference was found in dental age between males and females when compared to same growth pattern. CONCLUSION: Subjects with vertical growth pattern matured early than having the horizontal growth pattern in the same chronological age.

Photographic appraisal of crystal lattice growth technique.

Concept of creating mechanical retention for bonding through crystal growth has been successfully achieved in the present study. By using polyacrylic acid, sulphated with sulphuric acid as etchant, abundant crystal growth was demonstrated. Keeping in view the obvious benefits of crystal growth technique, the present SEM study was aimed to observe and compare the changes brought about by different etching agents (phosphoric acid, polyacrylic acid and polyacrylic acid sulphated) and to evaluate their advantages and disadvantages in an attempt to reduce iatrogenic trauma caused due to surface enamel alteration. Control and experimental groups were made of 24 and 30 premolars, respectively, for scanning electron microscopic appraisal of normal unetched and etched enamel surface and fracture site and finished surface evaluation. When compared with conventional phosphoric acid and weaker polyacrylic acid, investigations indicated that crystal growth treatment on enamel surface caused minimal iatrogenic trauma and surface alteration were restored to the original untreated condition to a large extent.

Maxillo- mandibular relationship--a cephalometric study.

An accurate assessment of apical base relationships using cephalometrics has been a perennial problem in orthodontics. The currently available literature suggests that reference points and planes are subject to change with treatment. Hence, an assessment of sagittal jaw relationship was done using five angular measurements and an attempt was made to determine the one which is statistically more accurate.

Linear assessment of anteroposterior jaw relationship.

Three Linear methods of establishing the sagittal relationship of the maxillary and mandibular apical bases were compared using Lateral skull radiographs of thirty individuals having Class II div. 1 malocclusion. Statistical evaluation was done for wit appraisal, AD' distance, and Wylie analysis. The A-D' distance is recommended for use during sagittal apical base relationship.

Cephalometric evaluation of Class II malocclusions in transitional dentition.

Studying malocclusion during active growth period is important because this period has the maximum impact on dentofacial structures. The present study comprises of computerised cephalometric evaluation of 100 North Indian children in the age group of 9-12 years, with 50 children in normal occlusion group. The samples were segregated according to sex with 25 females and 25 males in each group. It was concluded from the study that changes or deviations in SNB, Saddle, Articular and Gonial angles are the potential indicative factors in the development of a class II malocclusion and that class II pattern is associated with short and posteriorly placed mandible in relation to the cranial base.

Age prediction based on skeletal morphology.

Treatment plan for a child requires a complete diagnosis with monitoring of the skeleto-dental morphological changes during active period of growth. Growth modifications are done while the forces of growth are still at the peak of activity in a developing child. This study was undertaken on lateral cephalograms of 100 North Indian samples in the age group of 9-12 years consisting of 50 males and 50 females divided into normal occlusion and malocclusion groups, to predict and assess age by evaluating the skeleto-dental morphology in developing normal children having flush terminal plane molar relationship and children with developing class II pattern. It was concluded that based on measurements used in the study of dentofacial morphology, the age of a child could be statistically determined.

Biomechanical evaluation of bonding with glass ionomer cement.

This study was designed to determine the bond strength of three commercially available glass ionomer cements when used to bond mesh-backed medium twin standard edgewise (.022" x .028") brackets to enamel surface. The bond strength of one composite resin was compared with those of the glass ionomer cements. Scanning electron microscopic study of the debonded enamel surface was carried out to evaluate the effects of the bonding agents on enamel. The teeth were bonded with all the materials according to manufacturers' specifications. Each specimen was embedded in Dental stone with the bonded facial surface exposed. A special bracket holder was used to hold the brackets precisely under the wings during debonding. An Instron universal testing machine was used to measure the force required for bond failure. To simulate oral conditions, the direction of pull was so designed that it included an element of torsional stress along with tensile force. The findings indicate that Ketac-cem and Fuji II Glass ionomer cements hae adequate bond strength for clinical use. The scanning electron photomicrographs revealed that the enamel was least affected and well preserved in the Glass ionomer cement group. Further investigation is required to test the bond strengths of Glass ionomer cements clinically.