Soft tissue morphology of Jordanian adolescents

Divergence between CBCT and Optical Scans for Soft Tissue Analysis and Cephalometry in Facial Imaging: A cross-sectional study on healthy adults

BACKGROUND

Facial soft tissue analysis is becoming increasingly emphasized in orthodontic diagnosis and treatment planning. While traditional cephalometry primarily focuses on hard tissues, recent non-invasive imaging techniques offer the potential to comprehensively evaluate three-dimensional (3D) facial soft tissues. The aim of the study was to establish the geometrical 3D and cephalometric divergence between Cone Beam Computed Tomography (CBCT) derived images and scanned soft tissues. Crucial for enhancing orthodontic diagnosis, minimizing patient exposure to ionizing radiation and providing facial cephalometric parameters.

MATERIAL AND METHODS

A cross-sectional study was conducted from January 2020 to May 2023. CBCT and 3D facial scans were obtained simultaneously using a specialized imaging system. Reproducible landmark points were selected for both cephalometric and soft tissue analysis. Angular and linear measurements were recorded, and correlations between CT and facial scans were statistically assessed.

RESULTS

Comparisons between 10 CBCT-derived and 10 facial scan-based soft tissue representations resulted into 1.8mm mean root median square (RMS). Angular measurements, such as ANB, right gonial angle, and left gonial angle, exhibited a 0.9° of difference with their respective soft tissue variables. In contrast, linear measurements of total anterior facial height showed a lower correlation coefficient, equal to 0.51. The correlation between soft tissues and underlying hard tissues was more pronounced for gonial angles.

CONCLUSION

Facial soft tissue analysis using either 3D facial scans or CBCT-derived offers similar results for orthodontic diagnosis and treatment planning. These findings support the use of non-invasive diagnostic tools in orthodontics, although further investigations are needed to comprehensively understand the complexity of hard and soft tissue relationships.

Effect of body mass index on soft tissues in adolescents with skeletal class I and normal facial height

Background

The evaluation of soft tissues in patients undergoing orthodontic treatment plays a critical role in diagnosis and treatment planning. This study aims to evaluate the effect of body mass index (BMI) on facial soft tissues in skeletal Class I patients with normal vertical growth.

Methods

The study included 72 patients with a normal vertical growth pattern (SN-GoGn 26-38°) and skeletal Class I (ANB 2‒4°) malocclusion. According to their BMI (kg/m2) values, the patients were divided into three groups of 24 individuals each: underweight (>5th percentile) (13 females, 11 males; mean age, 11.58 ± 1.95 years), normal weight (5‒85th percentile) (12 females, 12 males; mean age, 11.54 ± 1.95 years), overweight (85‒95th percentile) (12 females, 12 males; mean age, 11.62 ± 2.01 years). Soft tissue thickness and height measurements were made on lateral cephalometric radiographs.

Results

In all soft tissue thickness measurements, except for the nasion, the overweight weight group had higher values. In comparing the underweight and normal weight groups, statistically significant differences were found in the thickness measurements at the nasion and gnathion (p < 0.05). The differences in thickness measurements at the glabella, labiale superius, stomion, labiale inferius, pogonion, gnathion, and menton are statistically significant between the underweight and overweight groups (p < 0.005). Comparing the normal and overweight groups revealed statistically significant differences the thickness measurements at the glabella, labiale superius, stomion, pogonion and menton (p < 0.05).

A Computational Tool for Detection of Soft Tissue Landmarks and Cephalometric Analysis

In facial aesthetics, soft tissue landmark recognition and linear and angular measurement play a critical role in treatment planning. Visual identification and judgment by hand are time-consuming and prone to errors. As a result, user-friendly software solutions are required to assist healthcare practitioners in improving treatment planning. Our first goal in this paper is to create a computational tool that may be used to identify and save critical landmarks from patient X-ray pictures. The second goal is to create automated software that can assess the soft tissue facial profiles of patients in both linear and angular directions using the landmarks that have been identified. To boost the contrast, we employ gamma correction and a client-server web-based model to display the input images. Furthermore, we use the client-side to record landmarks in pictures and save the annotated landmarks to the database. The linear and angular measurements from the recorded landmarks are then calculated computationally and displayed to the user. Annotation and validation of 13 soft tissue landmarks were completed. The results reveal that our software accurately locates landmarks with a maximum deviation of 1.5 mm to 5 mm for the majority of landmarks. Furthermore, the linear and angular measurement variances across users are not large, indicating that the procedure is reliable.

Skeleto-dental features among a sample of Saudi female children compared to British standards: A cephalometric study

Aim

This cross-sectional observational retrospective study aimed at assessing the cephalometric skeleto-dental features of class I, II, and III skeletal relationship of Saudi female school children sample and comparing the results to the established British Caucasian cephalometric standards.

Materials and Methods

The sample consisted of 205 retrospective lateral cephalometric radiographs of female school children. The age range of the subjects were between 10 and 13 years old with a mean age of 11 ± 1 years. Several cephalometric and constructed points were identified. Angular, linear, and proportional measurements were obtained and analyzed. The skeleto-dental features of class II and class III were compared to class I of this sample and then compared with the established British Caucasian population. Different angular, linear, and proportional variables were investigated. Descriptive statistics and Student's t-test were used for data analysis.

Results

The distribution of the skeletal relationship revealed that 68.3% of the sample showed class I relationship, 16.1% class II, and 15.6% class III. The result indicates significant differences among the different classes. A greater tendency towards class II facial pattern and more convex profile among Saudis were detected in the present study compared to Caucasians. Furthermore, The dento-alveolar relationship results showed more bi-maxillary protrusion among Saudi females compared to the British Caucasians.

Conclusion

The results of the study can serve as a base-line for future investigations in Saudi Arabia. Furthermore, the results obtained can also be of great value in distinguishing the various skeleto-dental features in the different skeletal classes among the Saudi females, and in the clinical diagnosis and treatment planning.

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

INTRODUCTION

This study established about 50 anteroposterior and vertical cephalometric norms of five tracing analyses in Iranians, using a large sample.

METHODS

Lateral cephalographs of 130 subjects (85 females, 45 males, with an average age of 22.77 ± 2.55 years (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).

RESULTS

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).

CONCLUSIONS

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.

Midsagittal facial soft tissue thickness norms in an adult Mediterranean population

The use of facial soft tissue thickness (FSTT) values is essential in forensic facial approximation. Few studies have assessed the FSTT norms in Mediterranean populations and none in the Lebanese population. The purpose of this study was to (1) present midsagittal facial FSTT norms for Lebanese adults with well-balanced faces and normal occlusion; (2) evaluate the presence of sexual dimorphism within these measurements; (3) establish a potential correlation between these measurements and (4) build on the existing database of FSTT data from previously published studies. FSTT measurements at 10 midsagittal locations were obtained from the lateral cephalometric radiographs of 87 males and 135 females (mean age of 23.49±6.24years). In additional to means, Shorth and 75-Shormax values are presented. Differences between sexes were assessed using the MANOVA test and correlations between different measurements were computed. The thinnest (3.07±0.72mm) and thickest (15.61±2.38mm) craniofacial soft tissue measurements existed at Rhinion and Subnasale, respectively. There was a statistically significant and large effect of sex on the combined FSTT variables (p<0.001; eta-squared=0.393). Males displayed larger FSTT values at all landmarks except at Glabella (p=0.162). Significant correlations were observed between almost all measurements with the highest being between the upper and lower lips (r=0.763) and between Pogonion and Gnathion (r=0.784). The descriptive values of FSTT values reported in this study add to the body of research necessary for the enhancement of facial approximation methods The uniquely strong effects of sex on FSTT measurements combined and on selected single FSTT measurements are an area for further research.

Soft-Tissue Anthropometric Norms of Iranians with Proper Occlusion and Inter-Ethnic Norm Comparisons

Background

Photographic soft-tissue norms of Iranian race are not reported previously, nor are they compared with other ethnicities. Besides, sex dimorphism is assessed in only very few studies on soft-tissue profile. The aim of this study was to assess the soft-tissue measurements of Iranians with good occlusion and the existing sex dimorphism and to compare the Iranian norms with other ethnicities.

Materials and Methods

Twelve anthropometric variables were measured by a dentist in 100 Iranian subjects with good occlusions. The subjects included 50 males and 50 females. The differences between the two genders, as well as the differences between Iranian norms and the norms in all other ethnicities available in the literature were statistically analyzed using a t test (α = 0.05).

Results

There were significant differences between males and females regarding frontonasal angle (P = 0.0000), mentolabial sulcus (P = 0.0000), vertical height ratio (P = 0.0000), vertical lip-chin ratio (P = 0.0013), nasolabial angle (P = 0.0019), lower vertical height-depth ratio (P = 0.0029), maxillary prognathism (P = 0.0045), and mandibular prognathism (P = 0.0118). The difference in facial convexity was marginally significant (P = 0.0543). Protrusions of both lips and horizontal distance between the lips were not significantly different between sexes (P > 0.2).

Conclusions

Unlike Americans and Brazilians but similar to Koreans, there was considerable sex dimorphism in Iranians. Compared to Iranian men, women might have more convex profiles, more advanced mandibles (unlike all other races studied), more protruded maxillae, lips closer to the middle of nose-chin vertical distance, deeper mentolabial sulci, less protruded noses with higher nose tips, and smaller lower faces.

Diagnostic value of profile photography in identifying departures from the norm of growth pattern and horizontal jaw relationship

BACKGROUND

Although the importance of facial photography in orthodontics has been recognized, there is only one study on its validity and absolutely no studies on its diagnostic value. This study was conducted, therefore, to evaluate for the first time the diagnostic merit of photography in detecting growth pattern and jaw relationships.

METHODS

Standardized lateral cephalographs and profile photographs were taken from 54 girls and 26 boys. On cephalometry, growth pattern (normal, horizontal, and vertical) and horizontal bimaxillary classification (Classes I to III) were determined. Using photographs, the angles FH-MP', CP'-MP', Sn-T-Me', cutaneous analog of ANB, facial convexity, and head position were calculated. Diagnostic photography-based measurements for detecting departures from the norm were calculated by counting correct and incorrect diagnoses, according to the gold standard (lateral cephalometry).

RESULTS

The sensitivity, specificity and positive predictive values, and the negative predictive value of FH-MP' photographic measurements in detecting growth disorders were 51.4, 77.8, 64.3, and 67.3 percent, respectively. These values were 45.7, 95.6, 88.9, and 69.4 percent for the CP'-MP' measurement, and were 40.0, 93.3, 82.4, and 66.7 percent for Sn-T-Me', and 51.4, 100, 100, and 72.6 percent for all of them combined. In detecting the horizontal relationship between the jaws, the photographic method showed an overall sensitivity, specificity, PPV, and NPV of 80.9, 63.6, 76.0, and 70.0 percent, respectively. These values were 80.9 57.6 73.1 67.9 percent for cutaneous analog of ANB, 87.2, 45.5, 69.5, and 71.4 percent for facial convexity, and 61.7, 66.7, 72.5, and 55.0 percent for head position.

CONCLUSIONS

Profile photography can be used as a perfectly accurate measurement tool for detecting horizontal and vertical growth patterns. It is also a rather accurate method for detecting the normal growth pattern, as well as both Class I and non-Class I jaw relationships. These results highlight this non-invasive and economic method as an effective clinical diagnostic tool.

Facial Anthropometric Norms of the Young Iranian Population

Introduction

Facial anthropometric measurement is considered an essential concern of surgeons, orthodontists, artists and forensic scientists. The aim of this study is to investigate facial anthropometric norms of the young Iranian population.

Methods

The study participants consisted of 200 healthy Iranian students (100 males, 100 females) aged 18-25 years old. Twenty-three liner and four angular measurements were investigated twice by a dentist. Independent-samples t test was used to compare indices between males and females and also between countries. A p value less than 0.05 was considered statistically significant.

Results

It was found that the mean measurements of c'-sn' of both sides, nasolabial angle, trichion-gnathion, tragion-tragion and gnathion-gnathion were statistically greater in Iranian males than in females (p < 0.05). Comparing Iranian anthropometric norms with North American Whites, Malays, Turkish and African American women demonstrated that there were statistically significant differences in most anthropometric measurements between Iranians and other populations (p < 0.05).

Conclusion

In Iranians, mean measurements of c'-sn' of the right and left sides, nasolabial angle, trichion-gnathion, tragion-tragion and gnathion-gnathion were greater in men than in women. Comparing Iranian males and females with different ethnicities indicated several interracial differences, which should be taken into consideration when dealing with patients or also practitioners originated in this region.

Soft tissue cephalometric norms of Iranian Class I adults with good occlusions and balanced faces

AIM

The aim of this study was to assess the soft tissue measurements of Iranians with good occlusion and to compare the Iranian norms with other ethnicities.

MATERIALS AND METHODS

A total of 25 anthropometric variables were measured by a dentist in 50 Iranian Class I subjects (25 males, 25 females) with good occlusion and well-balanced faces. The differences between the two genders, as well as the differences between Iranian norms and the Holdaway and Burstone analyses, were statistically analyzed using a t-test (α=0.05).

RESULTS

The subjects' mean age was 21.6±4.1 years. There were significant differences between males and females regarding the mentocervical angle, the nasolabial angle, Merrifield's Z-angle, the angle of facial convexity, soft tissue chin thickness, and upper lip thickness (P<0.05). The Holdaway norms can be used for the Iranian population, except for the following measurements which might be significantly different: facial convexity angle, nasolabial angle, interlabial gap, soft tissue facial angle, skeletal profile convexity, H-angle, lower lip to H-line, lower sulcus depth, and soft tissue chin thickness (P<0.05).

CONCLUSIONS

There was a considerable sex dimorphism in the Iranian population. The Holdaway norms are not useful for the Iranian population regarding most measurements.

Assessment of the soft tissue thickness at the lower anterior face in adult patients with different skeletal vertical patterns using cone-beam computed tomography

OBJECTIVE

To evaluate and compare the soft tissue thickness values at the lower anterior face among adult patients with different vertical growth patterns using cone-beam computed tomography.

MATERIAL AND METHODS

The study sample consisted of 105 adult patients (54 women and 51 men) with a normal sagittal skeletal pattern divided into three groups according to the vertical growth pattern: high-angle (women/men, 22/13; mean age, 24.54 ± 4.45 years), low-angle (women/men, 14/21; mean age, 24.62 ± 5.08 years), and normal-angle (women/men, 18/17; mean age, 24.22 ± 5.40 years) groups. The soft tissue thickness measurements at the lower anterior face in each group were done and analyzed using the one-way analysis of variance and Tukey tests.

RESULTS

Soft tissue thickness values were the lowest in the high-angle group for both women and men. For women, the thickness values at the labrale superius, labrale inferius, and pogonion were found to be statistically significantly smaller in the high-angle group (11.49 ± 1.05 mm, 12.70 ± 1.92 mm, and 11.64 ± 2.65 mm, respectively) compared with the values in the normal-angle group (13.31 ± 2.01 mm, 15.08 ± 1.94 mm, and 14.69 ± 3.08 mm, respectively) (P < .05, P < .05, and P < .01, respectively). For men, however, no statistically significant differences were found among the vertical growth patterns (P > .05).

CONCLUSION

Women had statistically significantly thinner thickness at the labrale superius, labrale inferius, and pogonion in the high-angle group compared with the normal-angle group.

Facial soft-tissue thickness in patients affected by bilateral cleft lip and palate: a retrospective cone-beam computed tomography study

INTRODUCTION

The purposes of this study were to evaluate the facial soft-tissue thicknesses and craniofacial morphologies of patients affected by bilateral cleft lip and palate (BCLP) and to compare the findings with a well-matched control group without any clefts using cone-beam computed tomography.

METHODS

The study sample consisted of 40 retrospectively and randomly selected patients divided into 2 groups: a BCLP group (20 patients; mean age, 13.78 ± 3.20 years) and an age- and sex-matched control group without clefts (20 patients; mean age, 13.94 ± 2.52 years). Craniofacial and facial soft-tissue thickness measurements were made with cone-beam computed tomography. The Student t test and multiple linear regression analyses were performed for the statistical evaluations.

RESULTS

The BCLP group had an increased SN-MP angle (P = 0.003), a decreased Co-A (P = 0.000), and retruded maxillary (P = 0.000) and mandibular (P = 0.026) incisors. In addition, patients affected by BCLP had statistically significantly decreased thickness measurements for the variables subnasale (P = 0.005) and labrale superior (P = 0.026) compared with the controls. The most predictive variables were found at U1-SN (r = 0.417, P = 0.004), IMPA (r = 0.368, P = 0.010), and ANB (r = -0.297, P = 0.031) for subnasale and U1-SN (r = 0.284, P = 0.038) for labrale superior.

CONCLUSIONS

The BCLP group showed greater vertical growth, greater retrusion of the maxilla and the maxillary and mandibular incisors, and decreased subnasale and labrale superior thicknesses compared with the well-matched controls without clefts. These differences should be taken into account when planning orthodontic and orthognathic surgery treatment for those patients.

Facial soft tissue thickness among skeletal malocclusions: is there a difference?

Objective

The purpose of this study was to determine the soft tissue thickness of male and female orthodontic patients with different skeletal malocclusions.

Methods

Soft tissue thickness measurements were made on lateral cephalometric radiographs of 180 healthy orthodontic patients with different skeletal malocclusions (Class I: 60 subjects, Class II: 60 subjects, Class III: 60 subjects). Ten measurements were analyzed. For statistical evaluation, one-way ANOVA and Kruskal-Wallis tests were performed. Least significant difference (LSD) and Dunnet T3 post hoc tests were used to determine the individual differences.

Results

Soft tissue thicknesses were found to be greater for men than for women. Statistically significant differences among the skeletal groups were found in both men and women at the following sites: labrale superius, stomion, and labrale inferius. The thickness at the labrale superius and stomion points in each skeletal type was the greatest in Class III for both men and women. On the other hand, at the labrale inferius point, for both men and women, soft tissue depth was the least in Class III and the greatest in Class II.

Conclusions

Soft tissue thickness differences among skeletal malocclusions were observed at the labrale superius, stomion, and labrale inferius sites for both men and women.

Three-dimensional gender differences in facial form of children in the North East of England

The aim of the prospective cross-sectional morphometric study was to explore three dimensional (3D) facial shape and form (shape plus size) variation within and between 8- and 12-year-old Caucasian children; 39 males age-matched with 41 females. The 3D images were captured using a stereophotogrammeteric system, and facial form was recorded by digitizing 39 anthropometric landmarks for each scan. The x, y, z coordinates of each landmark were extracted and used to calculate linear and angular measurements. 3D landmark asymmetry was quantified using Generalized Procrustes Analysis (GPA) and an average face was constructed for each gender. The average faces were superimposed and differences were visualized and quantified. Shape variations were explored using GPA and PrincipalComponent Analysis. Analysis of covariance and Pearson correlation coefficients were used to explore gender differences and to determine any correlation between facial measurements and height or weight. Multivariate analysis was used to ascertain differences in facial measurements or 3D landmark asymmetry. There were no differences in height or weight between genders. There was a significant positive correlation between facial measurements and height and weight and statistically significant differences in linear facial width measurements between genders. These differences were related to the larger size of males rather than differences in shape. There were no age- or gender-linked significant differences in 3D landmark asymmetry. Shape analysis confirmed similarities between both males and females for facial shape and form in 8- to 12-year-old children. Any differences found were related to differences in facial size rather than shape.