Soft Tissue Chin Thickness Research Articles

Comparison of Soft Tissue Chin Thickness in Adult Patients With Various Mandibular Divergence Patterns.

Objective This study aimed to compare the soft tissue chin (STC) thickness at different levels in patients presenting for orthodontic treatment with different vertical facial types. Materials and methods This comparative cross-sectional study was conducted at Sharif Medical & Dental College, Lahore, Pakistan, on 195 subjects. Patients presenting for orthodontic treatment, both genders, aged from 18 to 32 years, and Pakistani nationals were included. Patients with any craniofacial deformity, syndrome, cleft lip and palate, previous orthodontic or orthognathic treatment, and multiple missing teeth and prostheses in edentulous areas were excluded. Vertical facial patterns and STC thickness were recorded from pre-treatment lateral cephalograms. One-way analysis of variance (ANOVA) was applied to compare STC among various vertical facial patterns. Post-hoc analysis was done using the Tukey test. Results There were 126 females (64.62%) and 69 males (35.38%). The mean age was 21.66 ± 3.44 years. All three soft tissue chin thickness distances significantly differed among vertical facial patterns (p<0.001). Multiple comparisons show that the distance between soft and hard tissue pogonion was insignificant between low and normal anglefacial heights (p=0.5). Similarly, no significant difference was observed for the distance between softand hard tissue menton in low and normal angle subjects (p=0.4). The rest of the multiple comparisons were statistically significant (p<0.05). Conclusion The STC thickness is significantly associated with vertical facial divergence. While planning orthognathic surgery or genioplasty of the mandible, due consideration should be given to vertical divergence of the face to avoid unwanted facial changes.

Sex differences in craniofacial parameters of children and adolescents: a comparative study with the maturation of cervical vertebrae using a cephalometric method.

This study aimed to investigate sex differences in craniomaxillofacial parameters in children and adolescents. Lateral cephalograms were obtained from 340 subjects (141 male, 199 female) aged 6 to 18 years, and their craniofacial characteristics and cervical vertebral maturity were assessed using the quantitative cervical vertebral maturity (QCVM) method. Age-based stratified analyses on craniofacial parameters and further comparison in QCVM Ⅲ subjects were performed. Among all analyses, male subjects had significantly greater value than females in sex-different parameters except for facial convexity. The overall group had 17 sex-different parameters (ramus height, anterior facial height (AFH), posterior facial height (PFH), upper anterior facial height (UAFH), lower anterior facial height (LAFH), anterior cranial base length, posterior cranial base length, facial convexity, upper lip length, upper lip thickness, lower lip thickness, soft tissue chin thickness, nasion of soft tissue-subnasale (N'-Sn), subnasale-menton of soft tissue (Sn-Me'), subnasale-stomion inferius (Sn-Sto)). The <12 years old group showed 6 significant sex differences (AFH, LAFH, lower lip protrusion, lower lip thickness, N'-Sn, Sn-Me'). While the ≥12 years old group occurred two more parameters (mandibular body length, AFH/PFH) than the overall group. 12 cephalometric parameters had significant sex differences among QCMV III patients. After age adjustment, the number of sex-different parameters only increased in soft tissue. Craniofacial characteristics and cervical vertebrae maturation of the youngsters exhibited significant sex differences. Though females reached an earlier cervical vertebral maturation, they still had smaller craniofacial linear features. Sex differences should be taken into account in developing reference standards for cephalometric measurements and treatment planning in the clinic.

Evaluation of soft tissue chin thickness and lip thickness in different mandibular divergence patterns in Maratwada population-A cephalometric study

To evaluate the soft tissue chin thickness using different points on lateral cephalogram. To evaluate the lip thickness using different points on lateral cephalogram. To find correlation between soft tissue thickness and lip thickness in different mandibular divergence patterns.: The sample size consisted of 120 lateral cephalogram of subjects who had not undergone orthodontic treatment. Lateral cephalogram of 120 subjects was divided under 3 groups based on mandibular divergence into low angle, medium angle and high angle cases. The changes observed in three groups were assessed using the ANOVA test and Posthoc Bonferroni test.120 samples were collected according to the inclusion and exclusion criteria and cephalometric analysis was done. The correlation of the Mandibular Divergence and the soft tissue upper lip thicknessis statistically significant with a test value of 3.378 and a p value of 0.037. The correlation of the Mandibular Divergence and the soft tissue lower lip thickness is not statistically significant. The correlation of Mandibular divergence and soft tissue chin thickness at anterior part pog-pog is not statistically significant. The correlation of Mandibular divergence and soft tissue chin thickness at Angle of the chin Gn-Gn is statistically significant. The correlation of Mandibular divergence and soft tissue chin thickness at Inferior part Me-Me is not statistically significant.Soft tissue chin thickness was not uniform at all levels of chin.

Comparison Of Soft Tissue Chin And Lower Lip Thickness In Adult Patients With Various Mandibular Divergence Patterns.

The influence of hard tissue discrepancies on soft tissue cannot be ignored. The divergence or angle of the mandible can influence the lower lip and chin (soft tissue), similar to the influence of incisors inclinations on the pro/ retrusion of the lips. Hence this study was carried out to find out the impact of mandibular divergence patterns on the contour and thickness of lower facial soft tissues. Using the Lateral cephalograms of 105 subjects, Lip thickness was measured between the protruding endpoint of the maxillary incisors (U1) to the stomion point (St) and between the infra dentale (Id) and labrale inferius (Li). Soft tissue chin thickness was measured between the landmarks at hard tissue bony pogonion (Pog) to its opposite point on soft tissue (Pog'), hard tissue gnathion (Gn) to soft tissue gnathion (Gn') and hard tissue menton (Me) to its opposite point on ST menton (Me'). Lower lip thickness from Id-Li (infradentale labrale inferius) was greater in subjects with mandibular hyperdivergent pattern (p-value 0.097) while soft tissue chin thickness was decreased in hyperdivergent and increased in individuals with mandibular hypodivergence in both genders (p-value at gnathion was 0.596, menton was 0.023, and pogonion was 0.004, respectively). Lower lip thickness was increased in the individuals with mandibular hyperdivergence measured from infradentale to labrale inferius. While increased soft tissue thickness was observed at points gnathion and menton in patients with mandibular hypodivergence with no obvious difference at pogonion point.

Evaluation of facial profile characteristics of aesthetically pleasing Iranian faces.

The objective of this study was to assess the soft and hard tissue cephalometric indexes of facial profiles perceived as attractive. A total of 360 individuals (180 females and 180 males) with well-balanced faces and no history of orthodontic or cosmetic procedures were selected. Twenty-six raters (13 females and 13 males) rated the attractiveness of profile view photographs of the enrolled individuals. According to the total score, the rated top 10% of photographs were selected as attractive. Overall, 81 (40 soft tissue and 41 hard tissue) cephalometric measurements were made on traced cephalograms of the attractive faces. The obtained values were compared with orthodontic norms and attractive Whites using Bonferroni-corrected t tests. They were also analyzed regarding age and sex effects using a two-way ANOVA test. Significant differences were found between the cephalometric measurements of attractive profiles and orthodontic norms. Among the most important parameters were greater H angle and basic upper lip thickness in attractive males, and greater facial convexity and smaller nose prominence in attractive females. Also, attractive male participants had greater soft tissue chin thickness and subnasale perpendicular to the upper lip compared with attractive females. According to the results, males with a normal profile and thicker protruded upper lips were perceived as more attractive. Also, females with a slightly convex profile, deeper mentolabial sulcus, less prominent nose, and shorter maxilla and mandible were perceived as more attractive.

Effects of Age and Gender on Hard and Soft Tissue Cephalometric Features of an Iranian Population Over 12 Years Old

Background: This study aimed to investigate age- and gender-specific soft and hard tissue cephalometric features in an Iranian population with normal class I occlusion. Methods: A total of 111 Iranians (56 females and 55 males) in two age groups including individuals aged between 12-16 years and individuals aged over 16 years, with well-balanced faces and class I occlusion, were selected. Overall, 81 (40 soft tissue and 41 hard tissue) cephalometric measurements of the selected samples were traced on all cephalograms. The obtained values were compared in terms of gender and age differences and also ethnic differences between Iranian and European races. Results: This study indicated significant differences between Iranian men and women of different ages and Caucasians in terms of hard and soft tissue cephalometric measurements, which should be considered in orthodontic and surgical treatments. Some of the most important differences are greater values of facial convexity angle, nasolabial angle, and soft tissue chin thickness in Iranians than in Caucasians. Conclusion: In general, slightly more convex profiles, more protruded lips, less prominent noses, higher nose tips, and proclined and protruded central incisors are acceptable in the Iranian population. Also, Iranian women have more convex soft and hard tissue profiles, shorter anterior and posterior facial heights, larger interlabial gaps, less deep superior sulci, thinner and shorter upper lips, and thinner soft tissue chins than men. Also, non-growing adults have more advanced mandibles, larger noses, more sloping nasal tips, and larger skeletal dimensions compared with growing ones.

Holdaway Soft Tissue Cephalometric Standard for Malay Adults

Objectives: The aim of this study were: 1. To report facial soft tissue measurements in Class I Malay adult, 2. To compare between gender, 3. And to check applicability of Holdaway values for Class I Malay adults. Materials and Methods: Lateral cephalometric of 20 men and 20 women age 20-30 years with Class I skeletal was selected from Orthodontic Clinic, Faculty of Dentistry UiTM. The subject has no orthodontic or orthognathic surgery done before the radiograph was taken. The radiograph was traced and evaluated by the authors. Cephalometric landmarks were located according to Holdaway analysis. Ten linear and two angular measurements were produced on each radiograph and measured. For each variable, the mean and standard deviation (SD) was calculated using simple t-test (p&lt;0.05). Results: Soft tissue measurements for Malay have significant difference as compared to Holdaway value except for three parameters which are soft tissue facial angle, superior sulcus depth, and soft tissue chin thickness. When compared between genders, male has larger value in skeletal profile convexity, upper lip strain and soft tissue thickness while females demonstrated higher value in nose prominence and superior sulcus depth. Conclusions: It has been concluded that Malay values for Holdaway soft tissue analysis were found to be statistically different. Hence Holdaway soft tissue values are not applicable for use in orthodontic practice for Malay population. Further research to confirm values obtained for Malay population would aid in better diagnosis and treatment planning.

Ethnic-Guided Soft Tissue Cephalometric Analysis on Lambani Indian Inhabitants for Forensic Facial Reconstruction.

Background: Forensic craniofacial reconstruction is a combination of both scientific technique and artistic skill that assist facial soft tissue approximation on the skull to obtain an image of an individual that varies in the different ethnic groups depending on genetic and environmental factors such as soft tissue norms.Objectives: The present study was aimed to evaluate the soft tissue norms for Lambani Indian tribes spread across the state of Karnataka in India and compare them with the local inherent ethnolinguistic Kannadiga population.Material and methods: Forty healthy individuals encompassing 20 Lambanis and 20 Kannadigas were selected using demographic information. Lateral cephalograms obtained were analyzed for various soft tissue landmarks that include facial angle, upper lip curvature, skeletal convexity, H angle, nose tip to H-line, upper sulcus depth, lower sulcus depth, upper lip thickness, upper lip strain, lower lip to H line, soft tissue chin thickness, and glabella.Results: It was observed that glabella thickness, upper sulcus depth, and lower lip to H line showed a significant difference between Lambani and Kannadiga populations. Lambani’s have a higher facial angle than the Kannadiga group though not statistically significant. Gender-wise comparison had shown a significant difference in variables on upper sulcus depth, glabella among females, and lower lip to H line, glabella among males.Conclusion: The differences obtained between the two ethnic groups in this study clearly suggest the need for separate soft tissue thickness norms for distinctive populations that could be vital in the facial reconstruction of an individual in the field of forensic investigation to narrow down the identification process.

Assessment and Evaluation of Soft Tissue Measurements between Various Mandibular Divergences in the South Indian Population: A Cephalometric Study.

Aim:The aim of this study is to evaluate the association between the mandibular divergent patterns and soft tissue chin (STC) thickness measured at different chin levels in nongrowing patients.Methodology:Pretreatment lateral cephalograms of 400 adult patients were segregated into four groups based on mandibular divergence pattern defined by the mandibular plane to cranial base angle (average 32° ± 5°), Group I with low angle (below 27°), Group II with medium low angle (28°–32°), Group III with medium high angle (33°–36°), and Group IV with high angle (above 37°). STC thickness was measured between Pog-Pog' (pogonion), Gn-Gn' (gnathion), and Me-Me' (menton), thickness and height of the upper and lower lips were also measured. Statistical analysis was done using one-way analysis of variance followed by post hoc Tukey analysis.Results:A significant difference in the STC thickness at Pog, Gn, and Me was observed among all four groups with hyperdivergent patterns, showing decreased STC thickness than the hypodivergent mandibular pattern. Thickness of the upper and lower lips was greater in hypodivergent mandible, whereas height of the lips was greater in hyperdivergent mandible.

The comparison between the lower airway space, mandibular body, mandibular ramus, chin thickness and chin throat length in vertical and horizontal growers among skeletal class I and skeletal class II patterns – Retrospective cephalometric study

The vertical and horizontal growth influences the height of mandibular ramus and length of the mandibular body. The soft tissue chin thickness, the lower airway space and the chin throat length can vary in different growth patterns and different skeletal patterns. Lateral cephalograms of non-growing patients seeking orthodontic treatment (n=120) were included in the study. The samples were divided into two subgroups based on skeletal pattern (Cl I &amp; Cl II) according to ANB angle and Wit’s appraisal. Further sub divided into four groups based on cephalometric mandibular plane inclination to anterior cranial base (SN-GoGn) and Frankfort’s mandibular plane (FMA) angle in hypodivergent and hyperdivergent patterns. The parameters lower airway space, mandibular body, mandibular ramus, chin thickness and chin throat length were measured. Results showed maximum lower airway space, mandibular body, mandibular ramus, chin thickness, and chin throat length in the hypodivergent skeletal Class I group. The minimum lower airway space, mandibular body, mandibular ramus, chin thickness, and chin throat length observed in the hyperdivergent skeletal Class II group. The inter-group comparison of all samples indicates that there was a statistically significant difference between various groups and the measures of the hypodivergent samples are more than the hyperdivergent samples irrespective of the skeletal pattern. The study concludes that the lower airway, mandibular ramus, mandibular body, soft tissue chin thickness, chin throat length was less in hyperdivergent skeletal Class I and skeletal Class II samples than the skeletal Class I and skeletal Class II hypodivergent.

Evaluation of soft tissue cephalometric evaluation using Holdaway analysis in district Solan population.

INTRODUCTION: The soft tissue of the face requires an independent appraisal besides skeletal and dental analysis to comprehensively diagnose and plan treatment to meet objectives of orthodontic treatment leading to a pleasing profile. Soft tissue envelope of face plays an important role in esthetics, functional balance and facial harmony. AIM: The aim of the study was to evaluate soft tissue cephalometric evaluation using Holdaway analysis in district Solan population. MATERIALS AND METHOD: The study was conducted in the Department of Orthodontics and Dentofacial Orthopedics, Bhojia Dental College, Baddi, Distt. Solan(HP). Pretreatment lateral cephalograms of 60 subjects(30 males and 30 females) with Class II division 1 were taken. The patients aged between 12 and 26 years. Each of them fulfilled the following criteria, proclined maxillary anteriors, increased overjet, increased overbite, incompetent lips. Various cephalometric landmarks were identified and marked according to Holdaway analysis. The following measurements were recorded: Facial angle, H-line angle, upper sulcus depth, skeletal convexity at point A, Nose prominence, soft tissue subnasale to H-line, basic upper lip thickness, upper lip thickness, upper lip strain, lower lip to H-line, lower sulcus depth, soft tissue chin thickness. RESULTS: In the present study, significant variations were seen in facial angle, H-line angle, upper lip strain and lower sulcus depth when comparison of cephalometric measurement changes between males and females was done. CONCLUSION: District Solan population showed significant difference in facial profile with more facial angle in females and more H-line angle, upper lip strain and lower sulcus depth in males.

DETERMINATION OF CEPHALOMETRIC SOFT TISSUE NORMS FOR LOCAL POPULATION WITH NORMAL OCCLUSION USING HOLDAWAY ANALYSIS

Objective: To assess soft-tissue values in a group of local ethnic population with Class I occlusion by Holdaway‟s soft tissue cephalometric analysis, and to verify the pertinence of Holdaway‟s norms to local sample subjects.&#x0D; Study Design: Cross sectional study design.&#x0D; Place and Duration of Study: Orthodontics department, Bolan Medical College, Civil Sandman Hospital, Quetta, from Jun 2018 to Dec 2018.&#x0D; Methodology: Cephalometric radiographs of 69 Adults (33 males and 36 females) aged between 18-28 years, with normal occlusion and well aligned arches, were measured. Cephalometric landmarks were identified as stated by Holdaway analysis. On each radiograph two angular and nine linear measurements were evaluated.Results: Local ethnic population showed more convex profiles with higher skeletal convexity (1.97 ± 1.85) and H angles (15.05 ± 3.31), greater nose prominence (18.25 ± 3.73), upper lip thickness (13.43 ± 1.64), and soft tissue chin thickness (12.64 ± 1.94) compared to Holdaway‟s values. All values showed sexual dimorphism, amongst these statistically significant values (p&lt;0.05) were of soft tissue subnasale to H line, total upper lip thickness, nose prominence, soft tissue chin thickness and inferior sulcus to H line.&#x0D; Conclusion: Racial variance was present in sampled population, compared to Caucasian norms. These differences must be kept in the mind when planning and executing orthodontic therapy.

Gambaran Profil Jaringan Lunak Wajah Menurut Holdaway Kajian terhadap pasien ortodonti Rumah Sakit Gigi dan Mulut Fakultas Kedokteran Gigi Universitas Trisakti (Penelitian)

Background: The purpose of orthodontics treatment is to create the best balance among occlusal relationship, dental, and facial aesthetic, also the stability of the result. Facial profile analysis is one of proper method to precisely diagnose and decide an accurate treatment planning. Holdaway analysis considered as one of the most detailed because, Holdaway evaluate the entire facial profile. In general, malocclusion is associated with unaesthetic facial and dental appearances. So that, it becomes a main reason for patients to visit orthodontics clinic, especially to RSGM-FKG Usakti. Objective: To describe the average facial profile on orthodontics patient of RSGM-FKG Usakti using Holdaway’s method. Method: Observational research using cross sectional method to orthodontics patient of RSGM-FKG Usakti that came from January to December 2014. Eleven of Holdaway’s parameter was used as a measurement on sefalogram. The result of analytical line measurement collected in a tabulation of distribution-frequency. Result: Furthermore, The 11 measurements ; soft tissue facial angle, skeletal profile convexity, and H angle was convex. Sulcus labialis superior, lower lip to H line, and soft tissue chin thickness was ideal. Basic upper lip, upper lip strain, subnasal to H line and sulcus labialis inferior to H line was less ideal and prominence of small nose. Conclusion: The average facial profile on orthodontics patient of RSGM-FKG Usakti using Holdaway’s parameter is convex based on skeletal profile convexity and H angle.

Soft tissue analysis of chin, upper lip length and thickness in patients with different mandibular divergent patterns - A cephalometric study

Soft tissue analysis of chin, upper lip length and thickness in patients with different mandibular divergent patterns - A cephalometric study - IJODR- Print ISSN No: - 2581-9356 Online ISSN No:- 2581-9364 Article DOI No:- 10.18231/2455-6785.2018.0018, IP Indian Journal of Orthodontics and Dentofacial Research-IP Indian

Soft-tissue Cephalometric Norms of Kashmiri Population with Normal Occlusion and Well-balanced Faces

Objective: To establish soft-tissue cephalometric norms of Kashmiri population and to compare them with European-American norms.Material and Methods: A total of 102 subjects falling in the age group of 19 to 25 years were selected from random and representative sample of 5317. Reference lines were traced according to the definitions given by Holdaway, Rickett, Steiners, Merrifield, and nasiolabial angle. Thirteen linear and 4 angular measurements were analyzed on the lateral cephalogram of the sample.Results: Significant differences were found between male and female subjects in measurements of the soft-tissue facial angle, upper lip thickness, upper lip strain, lower sulcus depth and soft-tissue chin thickness, and upper lip to S line and nasiolabial angle. Soft-tissue cephalometric norms of Kashmiri population that were measured in the present study when compared with the norms set by Holdaway’s parameters, Rickett’s E line, Merrifield Z angle, Steiner’s S line, and nasiolabial angle did not fall within the normal range. The facial angle was found to be greater by 1.36°, upper lip sulcus depth was greater by 0.53 mm, convexity at point A was greater by 2.43 mm, the H angle was greater by 5.64°, upper lip thickness and strain were greater by 2.30 and 2.36 mm, respectively, soft-tissue chin thickness was greater by 0.92 mm, upper lip to S line was greater by 0.60 mm, and lower lip was greater by 0.91 mm when compared with the standard European-American norms.Conclusion: According to the present study, the measured soft-tissue cephalometric norms for Kashmiri population differed from the standard norms. When planning orthodontics treatment, it should be kept in mind that the profile may not necessarily be orthognathic.

Comparison of soft tissue chin thickness at different levels of chin in subjects with various growth patterns

To evaluate the association between mandibular growth pattern and soft tissue chin (STC) thickness measured at different chin levels and the gender differences in STC thickness at these different chin levels. Pretreatment lateral cephalograms of 161 subjects aged 18-45 years were selected, and subjects were divided into 4 groups depending on mandibular growth pattern defined by the mandibular plane to cranial base angle. The STC thicknesses were measured at pogonion (Pog), gnathion (Gn), and menton (Me). Group difference was evaluated using analysis of variance. STC thickness was greater (p < .05) in the low-angle group, and it gradually decreased across the groups, the least being in the high-angle group. No sexual dimorphism was observed among the groups (p > .05). This study suggests that STC thickness measurements were smaller in high-angle group compared to low-angle group.

Oft Tissue Proile Analysis by Means of Linear and Angular Parameters in Pakistani Population

Objective: The objectives of the study were to determine the soft tissue norms of non-growing adults of Pakistani origin and to assess any gender dimorphism in the soft tissue proile. Methods: A cross-sectional study was conducted on the lateral cephalograms of esthetically pleasing proiles of 70 undergraduate students aged 19-24 years of Dr. Ishrat ul Ebad Khan Institute of Oral Health Sciences. Several soft tissue linear and angular measurements of upper and lower lips, nose, and chin were carried out on lateral cephalogram. An independent sample t- test was used to compare cephalometric variables between genders. Results were taken signiicant at p-value ≤ 0.05. Results: Among the linear parameters, we found signiicant differences in upper lip length (p <0.001), thickness (p <0.001), prominence (p= 0.03), strain (p<0.001), sulcus depth (p = 0.01) and S plane to upper lip (p = 0.02). The lower lip linear parameters showed signiicant differences in E (p = 0.02) and S planes (p = 0.01), and H line (p <0.001). Among the angular parameters, we found statistically signiicant differences in the Z (p <0.001), H line (p = 0.01), angle of facial convexity (p<0.001), nasofacial (p= 0.04), nasomental (p= 0.05) and nasolabial angles (p<0.001). Conclusions: Males showed more prominent upper and lower lips, decreased prominence of nasal tip and increased soft tissue chin thickness as compared to females. Signiicant differences were found in various angular parameters among males and females.

Anteroposterior and vertical soft tissue cephalometric norms of Iranians, interethnic comparisons, sex dimorphism, and the effect of age on cephalometric variables.

This study established about 50 anteroposterior and vertical cephalometric norms of five tracing analyses in Iranians, using a large sample. Lateral cephalographs of 130 subjects (85 females, 45 males, with an average age of 22.77 ± 2.55years (range 20-29)) were traced manually using the Ricketts, Holdaway, Z-Merrifield, Epker, and Legan-Burstone soft tissue analyses. The role of age and sex on measurements, as well as the comparisons between Iranian norms with Caucasians from European decent, was determined statistically (α = 0.001). Age had no significant effect (all P values > 0.01). Sexual dimorphism existed in terms of numerous parameters. Compared to analysis standards, upper lip to E-plane, nose prominence, upper lip thickness, nasomental angle, Z angle, interlabial distance, subnasale perp to chin, subnasale-stomion:stomion-menton, subnasale-lower lip:lower lip-menton, interlabial gap, and vertical lip-chin ratio were smaller in Iranians. Superior sulcus depth, skeletal profile convexity, upper lip strain, upper lip curvature, H-angle, soft tissue chin thickness, nasofacial angle, subnasale perp to upper lip, subnasale perp to lower lip, maxillary prognathism, lower face throat angle, upper lip protrusion, lower lip protrusion, mentolabial sulcus, and lower vertical height-depth ratio were greater in Iranians compared to the norm (P ≤ 0.001). A great degree of sex dimorphism might exist among Iranians. Many textbook norms might not be the best options for diagnosis or treatment of Iranians.

Soft tissue growth changes from 8 to 16 years of age: A cross-sectional study.

Objective:The present cross-sectional study was conducted to evaluate and compare the soft tissue growth changes between males and females of two groups from 8 to 16 years.Materials and Methods:One hundred sixty skeletal class I lateral head cephalograms were screened aged between 8 to 16 years-Subjects were divided into two groups. Group I (8 to 12 years) and Group II (12 to 16 years) and further these groups were subdivided into male and female subgroups. Total eight linear and four angular parameters were studied.Results:All the parameters increased in their dimension while angle of total facial convexity including nose and Nasolabialangle decreases. Among the linear variables, Noseheight, Lip thickness at laberale inferious, Lip thickness at B point, Soft tissue chin thickness and Measurements of lips to E-plane were found significant for both subgroups. While rest of the linear variables like Upper lip height, Lower lip height, Nose depth and Sagittal depth also increased but this increase wasfound non-significant. Among the angular parameters angle of total facial convexity including nose and Nasolabialangle decreases and angle of facial convexity excluding nose, and Nose inclination increases with the age, and these changes were found non-significant.Conclusion:In this study, we observed that males showed a greater value of all parameters in comparison to females, and with the advancement of age, all the parameters increased, except for angle of total facial convexity and nasolabial angle.

Influence of heritability on craniofacial soft tissue characteristics of monozygotic twins, dizygotic twins, and their siblings using Falconer's method and principal components analysis.

ObjectiveThe purpose of this study was to investigate the influence of heritability on the craniofacial soft tissue cephalometric characteristics of monozygotic (MZ) twins, dizygotic (DZ) twins, and their siblings (SIB).MethodsThe samples comprised Korean adult twins and their siblings (mean age, 39.8 years; MZ group, n = 36 pairs; DZ group, n = 13 pairs of the same gender; and SIB group, n = 26 pairs of the same gender). Thirty cephalometric variables were measured to characterize facial profile, facial height, soft-tissue thickness, and projection of nose and lip. Falconer's method was used to calculate heritability (low heritability, h2 < 0.2; high heritability, h2 > 0.9). After principal components analysis (PCA) was performed to extract the models, we calculated the intraclass correlation coefficient (ICC) value and heritability of each component.ResultsThe MZ group exhibited higher ICC values for all cephalometric variables than DZ and SIB groups. Among cephalometric variables, the highest h2(MZ-DZ) and h2(MZ-SIB) values were observed for the nasolabial angle (NLA, 1.544 and 2.036), chin angle (1.342 and 1.112), soft tissue chin thickness (2.872 and 1.226), and upper lip thickness ratio (1.592 and 1.026). PCA derived eight components with 84.5% of a cumulative explanation. The components that exhibited higher values of h2(MZ-DZ) and h2(MZ-SIB) were PCA2, which includes facial convexity, NLA, and nose projection (1.026 and 0.972), and PCA7, which includes chin angle and soft tissue chin thickness (2.107 and 1.169).ConclusionsThe nose and soft tissue chin were more influenced by genetic factors than other soft tissues.