Soft Tissue Measurements Research Articles

D113. Comparison of Methodologies for Craniofacial Soft-tissue Cephalometrics: The Value of Virtual Reality

PURPOSE: Myriad options are available for soft-tissue analysis, which is vital to perioperative evaluation and research. Our objective is to compare accuracy, precision, and costs of available cephalometric modalities using facial soft-tissue measurements. METHODS: Twenty soft-tissue facial measurements were performed by 5 measurers of varying experiences on 5 adult subjects, using 6 methods - manual calipers, cone-beam CT, virtual reality (VR), 3D photogrammetry, iPad-based 3D photogrammetry, and 2-dimensional photos. Measurement sessions were timed and performed in triplicate, for a total of 9000 measurements. Intraclass correlation coefficient (ICC) was calculated for accuracy and one-way ANOVA was used for comparison. Coefficient of variation was compared among groups to evaluate precision of different methods, considering caliper measurements as the gold standard. RESULTS: ICC among raters was 0.932, indicating excellent reliability. VR was significantly faster than others (137 s vs 217 s for caliper, p<0.001). Coefficient of variation was highest for 2D photographs and lowest for VR (6.4 vs 11.0, p<0.001). The coefficient of variation of caliper was similar to all methods, except 2D photography which was significantly worse. Measurements with the greatest absolute difference from caliper measurements, across modalities, were those around the eyes (left to right exocanthion), tragion to antitragion, and tragion to exocanthion. CONCLUSION: 2D photography is not an accurate way for cephalometric measurements. Virtual reality is the fastest, has the lowest variation between measurements, and is equivalent to caliper measurements. For studies involving a large amount of cephalometrics, virtual reality measurements may be a good option to improve study throughput.

Soft-Tissue Response following Genioplasty Combined with Anterior Segmental Osteotomy.

The authors' main aim was to analyze soft-tissue response of the chin following genioplasty with anterior segmental osteotomy, which enables optimal surgical planning of genioplasty. Sixty-two patients who underwent genioplasty with concomitant anterior segmental osteotomy were divided into three groups depending on the direction of pogonion (Pog) movement: G1 (without sagittal change), G2 (advancement genioplasty), and G3 (setback genioplasty). All genioplasties included height reduction. Hard- and soft-tissue measurements with cephalometry were performed at T1 (before surgery), T2 (after surgery), and T3 (after orthodontic treatment) for the analysis of sagittal and vertical changes. Correlation and regression analyses were conducted to analyze soft- to hard -tissue movement and soft-tissue thickness changes. During the T1 to T2 period, the horizontal soft- to hard-tissue ratio at Pog was 0.85 in G2 and 0.80 in G3, and the vertical ratio at menton (Me) was 0.9 for all groups. The correlation coefficients were 0.64 (G2) and 0.83 (G3) at Pog and 0.9 (all), 0.85 (G1), 0.95 (G3) at Me. There was no significant correlation between initial soft-tissue thickness and soft-tissue response ratio. During the T2 to T3 period, no significant relapses were observed, which demonstrates the stability of anterior segmental osteotomy combined genioplasty. Clinically and statistically significant soft-tissue responses were demonstrated at Pog and Me. The higher values in G3 in particular suggest that setback genioplasty with anterior segmental osteotomy is an effective treatment alternative to conventional two-jaw surgery in some patients with bimaxillary prognathism with macrogenia. Therapeutic, IV.

3D Computed Tomography vs. 2D radiography: comparison of 3D direct anthropometry with 2D norm calculations and analysis of differences in soft tissue measurements.

The aim of this study was twofold: (1) to compare soft tissue measurements of the same distances obtained from 3D computed tomography reconstructions with 2D cephalometric radiograms, (2) to compare data from 3D measurements from direct anthropometry and 2D "norms" for the facial measurements. A total of 40 Caucasian patients that had their CBCT scans for various dental and dentoskeletal reasons were enrolled in this study. All the patients had large field of view (from the forehead to the chin). The data were stored in DICOM format and imported into a software for 3D reconstructions. After 3D facial soft tissue model generation, the distances between 18 soft tissue points were measured. The 3D soft tissue analysis was performed, and the facial indices were calculated. The mean 3D values were compared with 2D measurements performed on lateral cephalograms and Arnett's and Farkas' norms. The measurements were statistically compared using Student's t-test. Assessments from 2D and 3D measurements showed no statistical difference except for the distance Pogonion (for both male and female) and Labial superius prominence (females) to the True Vertical Line in 2D /Plane in case of 3D measurements. There was a significant difference between all 3D measurements and Arnett's and anthropometric Farkas' "norms". The mean difference between Farkas' "norms" and 3D measurements was within 3 mm for 70% of measurements. According to the results, 3D soft tissue analysis allows for complete diagnostic determination. The 3D "norms" are to be verified on a greater sample.

Immediate placement of one-piece zirconia implants with or without xenograft into the buccal gap. Soft tissues as secondary outcomes of an experimental in vivo study.

To histologically evaluate soft tissue healing following immediately placed one-piece zirconia implant and grafting a xenograft into the buccal gap. The third and fourth premolars (PM3 and PM4) in both quadrants of the mandible of nine dogs were used for this experiment. Those teeth were removed flapless and implants were placed into the distal sockets in a lingual position. In one side of the jaw, the gap between the implant and the socket walls was grafted (test) while no grafting was performed in the contralateral side (control), randomly selected. After 6months of healing, biopsies were obtained and prepared for histological analysis. Soft tissue measures like supracrestal soft tissue height (STH), length of barrier epithelium (BE), and connective tissue (CTC) were measured at buccal and lingual surfaces. The marginal mucosa was in a coronal position on the test side compared with the control side. At the buccal surface, the BE was longer in the test side than in the control side, while the CTC was longer in the control side than in the test side. For the STH (BE + CTC), the difference between the groups was not statistically significant. The placement of a xenograft into the gap between a 1-piece zirconia implant and the buccal wall in dogs modified the process of soft tissue healing, providing less soft tissue recession. The gap size seems to have a modifying effect on the application of this protocol.

The Lower Lip Profile Change During Total Distalization of the Mandibular Dentition

Objectives: This study aimed to determine the factors influencing the lower lip profile during Class III lower total arch distalization camouflage treatment. Methods: The cohort included 45 patients diagnosed with skeletal class III malocclusion. These patients underwent camouflage orthodontic treatment with lower arch total distalization. Lateral cephalograms were taken at the pretreatment and posttreatment stages. Cephalometric measurements were analyzed to unravel the influencing factors of the lower lip profile. This study defined new variables, i.e., CK and CKA, for detailed soft tissue analysis. Results: Novel soft tissue measurements presented in this study showed statistically significant changes after treatment. The CK angle and L1 to A Pog, L1 to NB, and IMPA were statistically correlated. Simple regression analysis was performed between variables. The formula was ΔCKA = 0.79(Δ L1 to NB) -1.6, and multiple regression resulted in ΔCKA = 0.5(Δ L1 to NB) – 0.42 (‘LL to Eline’, before treatment). Conclusion: The present study provided evidence that the lower lip evaluations, including the novel CKA and CKHA, were significantly related to the mandibular incisor position during total distalization of the mandibular dentition. The results demonstrated that clinically significant lip retraction could be obtained. Therefore, non-extraction with distalization must be suggested as the first treatment option in mild skeletal class III malocclusion patients.

Biologic and Mechanical Stability of Screw-Retained Layered Zirconia Crowns Bonded to CAD/CAM Titanium Abutments Using Angulated Screw Access: A Prospective Closed Cohort Study.

Purpose: To evaluate hard and soft tissue response and mechanical integrity for screw-retained layered zirconia crowns bonded to titanium nitride-coated titanium (TiN) CAD/CAM abutments supported by implants at 1- and 2-year follow-ups. Materials and Methods: A total of 46 patients were restored with a total of 102 free-standing implant-supported layered zirconia crowns, which were bonded to their respective abutments in the dental laboratory and delivered as a one-piece screw-retained crown. Baseline, 1-year, and 2-year data were collated on pocket probing depth, bleeding on probing, marginal bone levels, and mechanical complications. Results: Of the 46 patients, 4 patients with one implant each were not followed-up. These patients were not included in the analysis. Of the remaining 98 implants, due to failed appointments during the global pandemic, soft tissue measurements were recorded for 94 implants at year 1 and 86 implants at year 2, with a mean buccal/lingual pocket probing depth of 1.80/1.95 mm and 2.09/2.17 mm, respectively. Mean bleeding on probing was 0.50 and 0.53 at 1 and 2 years, which represents somewhere between no bleeding and a spot bleed according to the study protocol. Radiographic data were available for 74 implants at year 1 and 86 implants at year 2. The mean marginal bone change from baseline was +0.11 mm mesially and +0.19 mm distally at 1 year and +0.24 mm mesially and +0.16 mm distally at 2 years. The final bone level with respect to the reference point was +0.49 mm mesially and +0.19 mm distally at the end of the study period. Mechanical complications involving a slight misfit of the crown margin were recorded for one unit (1%), porcelain fracture for 16 units (16%), and a loss of preload for 12 units (12%) of < 5 Ncm (< 20% of initial preload). Conclusion: The biologic and mechanical stability of ceramic crowns bonded to CAD/CAM screw-retained abutments using angulated screw access was considered to be high, with overall bone gain, excellent soft tissue health, and only limited mechanical complications related to generally small fractures of the porcelain and a clinically insignificant loss of preload.

Fetal body composition and volumes study

Classification of abnormal fetal growth as “restriction” or “overgrowth” during an ongoing pregnancy is an important clinical challenge. Fetal soft tissue may reflect some of the earliest changes that occur in pathologic growth compared to traditional 2-dimensional (2D) estimates of fetal biometry. The Fetal 3D Study was designed to develop research and clinical applications for fetal soft tissue and organ volume assessment. Data collected in the NICHD Fetal Growth Studies included 2D fetal biometrics and 3D fetal volumes which were banked. In the Fetal 3D Study, sonographers performed longitudinal 2D and 3D measures targeting specific fetal anatomic structures. Each woman with a singleton had up to six research ultrasound scans while twins had up to seven. Of 2,802 with a singleton, 2,751 (98.2%) had 2D abdomen or 3D available and were included in the Fetal 3D Study. Of these, 2,435 (88.5%) had at least one 3D available (while 11.5% had only 2D abdomen) and 2,333 (84.8%) had at least one 3D that was measured. Out of 171 with a twin, there were 165 (96.5%) included: all had at least one 3D volume available and 152 (92.1%) had at least one 3D volume measured. Volume types with highest number of measures available were for the cerebellum, abdomen (liver and kidney) and thigh, based on protocol prioritization. After the first trimester, availability of 3D decreased with advancing gestational age (Table). For fetal organs with left and right sides (lungs, kidneys, and adrenal glands), it was more common that either side was able to be measured rather than both sides. Reliable 2D and 3D fetal biometry measurements depended on several factors including examiner training and experience, image quality, technique used to scan anatomic structures, fetal movement and position, and availability of 3D ultrasound software tools that allow rapid and reproducible measurements. Standardized procedures resulted in a large quantity of longitudinal fetal soft tissue and organ volume measurements from a diverse pregnant U.S. sample.

Skeletal, Dentoalveolar and Soft tissue Components of Skeletal Class II Malocclusion among Nepalese Orthodontic Patients: A Cephalometric Study

Introduction: The understanding of the craniofacial morphology of skeletal Class II malocclusion is a key element in planning orthodontic treatment. The aim of this study was to describe various skeletal, dentoalveolar, and soft tissue components of skeletal Class II malocclusion in Nepalese orthodontic patients. Materials and Method: This cross-sectional study was carried out at the Universal College of Medical Sciences (UCMS) in the Department of Orthodontics and Dentofacial Orthopedics. Lateral cephalograms of 70 patients with skeletal class II malocclusion of age greater than 1 8 years, and ANB &gt; 4°, were traced. Various skeletal, dentoalveolar, and softtissue measurements were taken. Descriptive statistics were performed followed by an independent sample t-test to find the difference in mean of various cephalometric parameters between males and females. Result: Among 70 subjects, 54 samples had class II div 1 malocclusion and 16 had class II div 2 malocclusion. Mandibular retrognathism was seen in 37 subjects having skeletal Class II Div 1 malocclusion and in 9 subjects with Class II Div 2 malocclusion. The mean value of SNA was 82.91 ° ± 2.87°, SNB was 76.81 ° ± 2.97°, and ANB was 6.11 ° ± 1.22° in Class II Div 1 subjects. In subjects with Class II Div 2, the mean value of SNA was 82.31 ° ± 3.19°, SNB was 76° ± 4.08°, and ANB was 5.44° ± 1.21 °. Mean value of U1 to NA degree and linear measurement was Class II div 1 was 28.30° ± 6.86° degree and 5.56 ± 2.76 mm respectively. Similarly, mean value of LI to NA degree and linear measurement was 31 .93° ± 5.96° and 6.16 ± 2.37 mm respectively. Mean and standard deviation value of upper lip to S-line and lower lip to S-line was 2.85 ± 2.1 3 mm and 3.54 ± 2.47 mm respectively in Class II Div 1 subjects. Similarly, in Class II Div 2 it was 1.50 ± 2.16 mm and 0.13 ± 2.66 mm respectively. Mean and standard deviation value of nasolabial angle was 93.69° ± 12.91° in Class II div 1 and 96.38° ± 12.26° degree in Class II Div 2. The mean values of most cephalometric parameters did not differ statistically between male and female subjects with Class II div 1 malocclusion. Conclusion: In subjects with skeletal Class II mean value of SNA was within normal range whereas SNB was decreased. Retrognathia and a small mandible in relation to the cranial base with a well-positioned maxilla were observed in the majority of subjects. Mean U1 to NA angular and linear measurement was increased in Class II Div 1, whereas they were decreased in Class II Div 2.

Gambaran Profil Jaringan Lunak Pasien Berdasarkan Analisis Holdaway "Analisis Sefalometri Pada Pasien Usia 6-12 Tahun di RSGM-P FKG Usakti" (Laporan Penelitian)

Background: Malocclusion is an occlusion that deviates from the normal state. Diagnosis and orthodontic treatment plan might use Holdaway soft tissue cephalometric analysis. Holdaway's analysis is more detailed and clear because it has 11 parameters in soft tissue measurements, namely facial angle, nasal crest distance, upper lip sulcus depth, H angle, Subnasal distance to H line, skeletal convexity, thickness of the base of the upper lip, upper lip strain, distance Li to H line, ILS distance to H line and chin thickness. Objective: To describe the soft tissue profile of patients based on Holdaway analysis in patients aged 6-12 years at RSGM-P FKG Usakti. Methods: Descriptive observational study with a cross-sectional design on orthodontic patients aged 6-12 years at RSGM-P FKG Usakti in 2018-2019. Results: The mean facial angle of the patient was 88.3°, nasal crest was 5.12 mm, the mean upper lip sulcus depth was 3 mm, the mean H angle was 16.68°, the mean Sn-H was 7.77 mm, the skeletal convexity was 3.75 mm. , the thickness of the upper lip base was 11.37 mm, the upper lip strain was 11.52 mm, the Li-H average was 2.56 mm, the ILS-H average was 2.59 mm and the chin thickness measurement was 11.09 mm. Conclusion: This study showed that the patient had an ideal upper lip sulcus depth, ILS-H distance, and chin thickness meanwhile the facial angle, H angle, and skeletal convexity are convex. The Sn-H distance, thickness of the upper lip base, upper lip strain, and Li-H distance are less than ideal, accompanied by a small nose crest distance

Relationship of psychosociocultural factors with dental malocclusion and facial appearance

Objectives: The purpose of this study was to evaluate the relationship between psychosociocultural factors and dental malocclusion, facial appearance, and body perception. Material and Methods: The study was carried out with the participation of 112 female and 113 male individuals between the ages of 18 and 25. Individuals were asked to answer the Rosenberg Self-Esteem Scale, Physical Appearance Comparison Scale Revised, and Sociocultural Attitudes Towards Appearance Questionnaire 4-Revised questionnaires. Individuals were divided into three groups Class I, Class II, and Class III according to dental molar relationships. Standard facial and profile photographs of individuals in all groups were taken and soft-tissue measurements were performed. Results: There was no significant psychosociocultural difference between male and female individuals. However, individuals with Class III dental malocclusion compare their physical appearance more than other malocclusion groups and more experience body dissatisfaction (P &gt; 0.05). Individuals with Class III dental malocclusion have higher lower face height, lower lip height, mentolabial angle, facial convexity angle, total facial convexity angle values, and lower forehead height/lower face height, nose height/lower face height ratio, and projection of the upper lip relative to the chin. Individuals with Class II dental malocclusion have lower chin height and anterior mandibular height/lower face height ratio, higher upper lip height/lower face height ratio, and upper lip height/anterior mandibular height ratio. Individuals with Class I dental malocclusion have a lower upper face height/lower face height ratio. Conclusion: Dental malocclusion groups have different facial soft tissue properties. Dental malocclusion and the facial appearance of individuals affect their lives in terms of psychosociocultural aspects.

Reliability of 3D Stereophotogrammetry for Measuring Postoperative Facial Swelling.

This study aimed to determine the reliability of three-dimensional (3D) stereophotogrammetry as a measurement instrument for evaluating soft tissue changes in the head and neck area. Twelve patients received a bilateral sagittal split osteotomy (BSSO). Test and retest 3D photographs were captured within the first three postoperative weeks, and a reference 3D photograph was capture at three months postoperatively. Distance measurements, mean and root mean square of the distance map, and volume differences were obtained. Reliability of these parameters was assessed by intraclass correlation coefficients (ICCs), standard error of measurement (SEM), and smallest detectable change (SDC). All distance measurements had an ICC > 0.91, and the distance map parameters and volume differences showed ICCs > 0.89. The neck region presented the largest SEMs (5.09 mL) and SDC (14.1 mL) for the volume difference. In conclusion, 3D stereophotogrammetry is reliable for distance and volume measurements of soft tissues in patients after a BSSO advancement.

Effects of Surgically Assisted Rapid Palatal Expansion on Facial Soft Tissues: A Systematic Review

Surgically assisted rapid palatal expansion (SARPE) is a successful method for treating transverse discrepancies in adult patients. The relocation of maxillary segments may induce changes at the surrounding soft tissues as well. The aim of this systematic review was to examine the possible effects that SARPE may have in the soft tissues of the face. Our search strategy included electronic databases (Pubmed, Scopus, ProQuest, Google Scholar, Cochrane Library) and a hand search of the reference list of found reviews. A priori definition of inclusion and exclusion criteria was made. Finally, 15 articles were included in qualitative synthesis. Risk of bias was generally high among the included studies. Study outcomes included nasal, labial, nasolabial and other facial soft tissue measurements. The evaluation of the changes was two-dimensional in six studies, and three-dimensional in nine studies. Meta-analysis was unfeasible due to lack of standardization, important methodological limitations, and shortcomings of the studies. A post-surgical increase in the dimensions of the alar width and the alar base width was commonly reported among the included studies. However, the above should be considered with caution due to the high risk of bias and the inability for quantitative synthesis.

Skeletal and dental manifestations of Glucose-6-phosphate dehydrogenase deficiency, thalassemia, and sickle cell anemia patients in Saudi Arabia.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency, Thalassemia (THL), and Sickle cell anemia (SCA) are the most common inherited hematologic diseases globally. It is important to understand the skeletal and dental manifestations in orthodontic treatment. This study aimed at assessing and comparing skeletal and dental manifestations of G6PD deficiency, THL, and SCA patients with healthy controls in Saudi Arabia. This is a retrospective study of G6PD deficient, THL, and SCA patients' cephalometric records in Saudi Arabia. This study included 136 subjects (G6PD=34, THL=34, SCA=34, and healthy control=34), aged between 18-32 years. 17 skeletal, dental, and soft tissue cephalometric measurements obtained from the G6PD, THL, and SCA were compared to control measurements using ANOVA and Tukey's HSD post-hoc test. Intra-class correlation ranged between (ICC: 0.971-0.996), indicating excellent reliability of measurements. A statistically significant difference in skeletal, dental, and soft tissue measurements between each condition and controls was observed, except for Wits, PP-MP, Y-axis, UI-SN, NLA, and LI-E line in SCA, FMA, ANS-Me, UI-SN, and LI-A Pog in G6PD and Wits, Y-axis, UI-SN, UI-NA, LI-MP, LI-Apog and UI-E line in THL group (p˃0.05). SCA and THL patients showed class II skeletal patterns, while class III skeletal relationship was evident in patients with G6PD deficiency.

Alterations in Facial Soft Tissue Thickness Post-Facemask Treatment in Noncleft Skeletal Class III and Bilateral Cleft Lip Palate Class III Patients.

The purpose of this retrospective study was to assess the alteration in the facial soft tissue thickness after rapid maxillary expansion with facemask treatment in bilateral cleft lip and palate (BCLP) Class III patients and noncleft Class III patients. Case records including lateral cephalograms of 30 patients (19 females, 11 males) treated using a rapid maxillary expansion with facemask treatment were analyzed. Group I (age: 11.4 ± 1.02 years) (10 females, 5 males) consisted of noncleft skeletal Class III patients, and group II (age: 10.8 ± 0.84 years) (9 females, 6 males) comprised skeletal Class III patients with bilateral cleft lip and palate. Fifteen hard tissue and 10 soft tissue measurements were made at the beginning and at the end of the treatment to evaluate the change with rapid maxillary expansion combined facemask treatment. The bilateral cleft lip and palate group displayed a statistically significant increase in the thickness of the subnasale, labrale superius, labrale inferius, labiomentale, and pogonion, whereas the thickness of the stomion was found to be significantly decreased. The noncleft group demonstrated a statistically significant decrease in the thickness of the stomion and gnathion. There was a statistically significant difference between the bilateral cleft lip and palate and noncleft groups in the facial soft tissue thickness measurements at labrale superius, gnathion, and subnasale points and in Y axis, U1-SN, U1-NA in the hard tissue measurements. The results of the study indicated that the rapid maxillary expansion with facemask treatment produced diverse alterations in the facial soft tissue thickness of bilateral cleft lip and palate patients and noncleft Class III patients.

The accuracy of a three-dimensional face model reconstructing method based on conventional clinical two-dimensional photos

BackgroundThis study aims to investigate the accuracy of a three-dimensional (3D) face reconstruction method based on conventional clinical two-dimensional (2D) photos.MethodsTwenty-three patients were included, and Character Creator v3.2 software with the Headshot v1.0 plugin was used for 3D face model reconstruction. Various facial landmarks were finely adjusted manually to refine the models. After preprocessing and repositioning, 3D deviation analysis was performed. The accuracy of the landmarks in different dimensions was determined, and twelve facial soft tissue measurements were compared to validate the clinical potential of the method.ResultThe reconstructed 3D face models showed good facial morphology with fine texture. The average root mean square errors between face scan models and reconstructed models at perioral area (1.26 ± 0.24 mm, 95%CI: 1.15–1.37 mm) were significantly smaller than the entire facial area (1.77 ± 0.23 mm, 95%CI:1.67–1.88 mm), P < 0.01. The deviation of menton of soft tissue was significantly larger than pronasale (P < 0.01). The deviations of all landmarks in the Y-direction were significantly larger than those in the other 2 dimensions (Y > Z > X, P < 0.01). A significant difference (P < 0.05) of approximately 1.5 mm was found for facial height. Significant differences (P < 0.05) were also identified in the remaining 6 soft tissue measurements, with average deviations no greater than 0.5 mm (linear measurement) or 1.2° (angular measurements).ConclusionA 3D face modeling method based on 2D face photos was revealed and validated. The reconstruction accuracy of this method is clinically acceptable for orthodontic measurement purposes, but narrow clinical indications and labor-intensive operations remain problems.

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.

Aging of the Nose: A Quantitative Analysis of Nasal Soft Tissue and Bone on Computed Tomography.

Morphologic and anatomical changes of the aging nose affect the surgical strategy of rhinoplasty in older patients, but age-related changes in noses have yet to be fully characterized. This study aimed to determine the evolution of nasal soft tissue and bone in aging noses using computed tomography. Computed tomographic images of 200 Asian patients were included. The study population was divided into two groups according to age and sex: a younger group (20 to 35 years of age) and an older group (65 to 80 years of age). Measurements of nasal soft tissue and bone on computed tomography were performed using Osirix 9.0 software. With regard to soft-tissue changes, the nasal skin and soft-tissue envelope thickness at rhinion, supratip, and nasal tip increased significantly with aging in both sexes. Increase of nasal depth and decrease of nasolabial angle were significant in both sexes. Nasal length and nasofrontal angle showed significant age-related increases in men; decrease of nasal tip angle and increase of pyramidal angle were significant in women. With regard to nasal bone changes, the bone length decreased significantly in women and the bone thickness decreased significantly in both sexes. Nasofrontal angle in men and pyramidal angle in women increased significantly. These results suggest that the aging process leads to drooping of the nasal tip, thickened nasal skin and soft tissue, and resorption of the nasal bone, providing a reference for rhinoplasty in older patients.

The Heritability of Upper Airway Dimensions Using MRI Scans in Twins

Introduction: Obstructive sleep apnea (OSA) is a common disorder characterized by the repetitive collapse of the upper airways during sleep, most likely in the oropharyngeal region. Anatomical factors significantly contribute to the disease development; however, the heritability of the upper airway dimensions, which lead to the collapsibility of the upper airways, is less known. In the current study, we aimed to quantify the impact of heritable and environmental factors on the upper airway dimensions in twins using magnetic resonance imaging (MRI). Methods: We completed head and neck MRI imaging on 110 (66 monozygotic and 44 dizygotic, age median and Q1–Q3: 53 (44–63.75) years) adult twins from the Hungarian Twin Registry. We completed cephalometric, soft tissue and fatty tissue space measurements on T1- and T2-weighted images in sagittal, coronal and axial planes. For the analysis of the genetic and environmental, the determination of the measured parameters was performed with an ACE twin statistical model. Results: We found a strong genetic determination in the anteroposterior diameter of the tongue and the thickness of the submental fatty tissue of the neck. Other parameters of the tongue, soft palate and uvula have shown moderate heritability, while we found strong environmental determination in the thickness of the parapharyngeal fatty tissue, the thickness of the pharyngeal wall, and the smallest diameter of the posterior upper airways. Conclusion: Our twin study can help better understand the genetic and environmental background of anatomical structures involved in the development of sleep apnea.

A Preliminary Study of a Novel Reference Plane of the Head: Comparing With the True Horizontal Plane.

A new reference plane of the head, based on soft tissue landmarks and suitable for clinical analysis and soft tissue measurements, is needed. We recently discovered a novel reference plane, that is, the COs plane, which was formed by bilateral Lateral Canthus and bilateral Otobasion Superius and might be horizontal at the natural head position (NHP). In this study, we investigated the angles between the COs plane and the true horizontal (TrH) plane while sitting and standing, aiming to explore whether the new plane could be used as a substitution for the reference plane in clinical practice. Briefly, 26 volunteers were enrolled. Their sitting and standing NHP were recorded using the 3dMDface system. In the pitch axis, the mean angle of COs/TrH was 0.29 degrees and 0.41 degrees for sitting and standing positions, respectively, showing no statistical difference ( P >0.05). However, in the roll axis, the mean angle of COs/TrH for sitting position and standing positions was 1.08 and 1.33 degrees ( P <0.05), which was considered to be the result of habitual canting of the head. Moreover, there were no significant differences between the sitting and standing NHP, considering the COs/TrH angles ( P >0.05). To sum up, we concluded that the COs plane could be used as a reliable reference plane in certain soft tissue analysis and clinical applications.

Combining Unique Planar Biaxial Testing with Full-Field Thickness and Displacement Measurement for Spatial Characterization of Soft Tissues.

Soft tissues rely on the incredible complexity of their microstructure for proper function. Local variations in material properties arise as tissues develop and adapt, often in response to changes in loading. A barrier to investigating the heterogeneous nature of soft tissues is the difficulty of developing experimental protocols and analysis tools that can accurately capture spatial variations in mechanical behavior. In this article, we detail protocols enabling mechanical characterizations of anisotropic, heterogeneous soft tissues or tissue analogs. We present a series of mechanical tests designed to maximize inhomogeneous strain fields and in-plane shear forces. A customized, 3D-printable gripping system reduces tissue handling and enhances shear. High-resolution imaging and laser micrometry capture full-field displacement and thickness, respectively. As the equipment necessary to conduct these protocols is commercially available, the experimental methods presented offer an accessible route toward addressing heterogeneity. © 2022 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Unique biaxial testing of soft tissues and tissue analogs Basic Protocol 2: Full-field thickness measurement of soft tissues and tissue analogs Support Protocol 1: Creating and speckling cruciform-shaped samples for mechanical testing Support Protocol 2: Creating custom gripping system to minimize sample handling.