Transverse Dimensions Research Articles

Tooth-Bone-Borne vs Bone-Borne Rapid Maxillary Expanders on Dentoskeletal Changes.

This study compared the insertion and thickness of the cortical bone, the parallelism of the midpalatal suture, and the skeletal transverse dimension using a microimplant-assisted rapid palatal expansion (MARPE) with those produced by bone-anchored maxillary expander (BAME) in adults. The sample comprised 18 patients (mean age, 29.9±9.4 years) selected for the MARPE group and 18 (mean age 24.8±6.8 years) selected for the BAME group. Cone-Beam computed tomography scans taken just before and after the expansion. After treatment, there was a significant palatal depth decrease. In addition, maxillary and mandibular width were increased in both groups. Regarding the cortical bone insertion and cortical bone width, it is shown an increase in both groups but those changes are not significant. However, the anterior suture opening effect occurs more frequently in the BAME than in the MARPE device. There are no differences in the frequency of opening of the midpalatal suture in the cases treated with MARPE and BAME, in both cases the most frequent opening morphology is parallel, independently of midpalatal suture maturation. There are no differences in the use of MARPE or BAME in the parallelism of the middle palatal suture, the cortical bone insertion, and thickness according to the maturation stages of the midpalatal suture but significantly increases the transverse dimensions of the maxillary skeleton.

Evaluation of the accuracy of full-arch impressions between three different intraoral scanners and conventional impressions: A prospective in vivo study.

This in-vivo study evaluated the accuracy of full-arch digital impressions obtained through different intraoral scanning technologies regarding trueness and efficiency against the standard alginate impressions. Alginate impressions were taken from 50 subjects, and the resulting stone casts were scanned using the Trios 3Shape desktop scanner. In-vivo scans were conducted on each participant using three intraoral scanners: Medit, CEREC Primescan, and 3Shape Trios. The scanned files were superimposed onto two software platforms: the 3Shape Orthoanalyser and Geomagic software. This superimposition was performed against the reference model to calculate 3D and 2D deviations, enabling efficiency comparisons between digital and traditional workflows based on work time in minutes. Measurements and comparisons were made in three planes: transverse, sagittal, and vertical dimensions for all the models and stone casts. Statistical analysis employed SPSS 23, with the significance level set at P<0.05. Significant deviations were observed between the three intraoral scanners and the alginate impression, with molar and premolar areas showing greater imprecision across dental arches. Compared to the alginate technique, Medit i500 tended to reduce the transverse dimension in the areas mentioned above, while CEREC exhibited higher precision. Molar and premolar areas emerged as the regions with the greatest discrepancies, both in excess and deficiency, compared to the alginate impression. This difference in dimensions was, however, statistically insignificant overall. 3Shape Trios exhibited the shortest scan times, indicating higher efficiency. Among the intraoral scanners, Medit recorded the longest scanning duration. Accepting the null hypothesis, the scans obtained using all three scanners were comparable with statistically insignificant differences in the measurements. The three scanners differed in the total scan time taken, with the Medit scanner requiring the longest scan time and the 3Shape TRIOS 3 scanner demonstrating the shortest scan duration.

The Complexity of Skeletal Transverse Dimension: From Diagnosis, Management, and Treatment Strategies to the Application of Collaborative Cross (CC) Mouse Model.

This study investigates the significance of skeletal transverse dimension (STD) in orthodontic therapy and its impact on occlusal relationships. The primary goal is to enhance understanding and promote the integration of transverse skeletal diagnostics into routine orthodontic assessments. To achieve this aim, the study employs a comprehensive approach, utilizing model analysis, clinical assessments, radiographic measurements, and occlusograms. The initial step involves a meticulous assessment of deficiencies in the maxilla, mainly focusing on transverse dimension issues. Various successful diagnostic methods are employed to ascertain the type and presence of these deficiencies. Furthermore, the study compares surgically assisted maxillary expansion (SARME) and orthopedic maxillary expansion (OME) in addressing skeletal transverse issues. Stability assessments and efficacy analyses are conducted to provide valuable insights into the superiority of SARME over OME. The findings reveal that proper evaluation of STD is crucial in orthodontic diagnosis, as overlooking transverse dimension issues can lead to complications such as increased masticatory muscle activity, occlusal interferences, and an elevated risk of gingival recession. Surgically assisted maxillary expansion emerges as a more stable solution than orthopedic methods. In conclusion, incorporating skeletal transverse diagnostics into routine orthodontic assessments is imperative for achieving optimal occlusal relationships and minimizing negative consequences on dentition, periodontium, and joints. The study emphasizes the significance of accurate three-dimensional assessments and recommends the consideration of SARME over OME for addressing skeletal transverse deficiencies. Finally, the Collaborative Cross (CC) mouse model is also a novel mouse model for studying complex traits. Exploring the Collaborative Cross mouse model opens avenues for future research, promising further insights into transverse skeletal issues in orthodontics.

An exploration of the enigmatic ponticulus posticus: a cone beam computed tomographic study

During embryonic development, the activity of neural crest cells has the potential to induce the ossification of the posterior atlantooccipital ligament, resulting in the formation of an abnormal bony bridge known as “Ponticulus Posticus” (PP). The presence of PP increases the likelihood of vertebral artery obstruction, and patients with this condition frequently exhibit symptoms of vertebrobasilar insufficiency. Furthermore, connections have been depicted between PP and dental agenesis, malocclusions, and cleft lip and palate. This study assessed the prevalence, morphology, and superior articular facet (SAF) dimensions in PP using Cone Beam Computed Tomography (CBCT). In this retrospective study, SPSS 22.0 was used to analyse 202 cervical CBCT images devoid of pathologies. PP, age, and sex relationship were examined using the t-test and chi2 analysis. Pearson correlation examined the relationship between PP and non-PP SAF dimensional differences. P values &lt;0.05 were significant. The prevalence of PP was 8.4%, with 64.7% constituting complete type and 35.2% partial type. The unilateral partial group’s anteroposterior (D1) and transverse (D2) dimensions showed a strong positive association and significant difference. Understanding this anomaly and the changes it can cause in depth is essential for a clinician to diagnose orofacial pain. Taking into account the benefits of using CBCT enables a detailed evaluation of the vertebral column in three different planes, allowing us to measure the metrical dimensions of SAF precisely in the present study. It can be considered a gold standard in evaluating PP as a diagnostic tool.

Mechanical strength measurement of needle-shaped CaSO4 microcrystals by a three-point bend test

A simple method for direct measurement of the mechanical strength of needle-shaped microcrystals of calcium sulfate, CaSO4, is proposed. The microcrystals, with a length from 30 to 50 μm and transverse dimensions from 1 to 3 μm, can act as reinforcing filler in various structural and building composites to improve their mechanical properties. The method is based on a three-point bend test, adapted to microscopic objects. The CaSO4 microcrystals were placed on a substrate, which was a twill-weave filter mesh consisting of intertwined steel fibers with diameter of ∼25 μm. Due to the twill weave, the mesh surface is characterized by a periodic distribution of protrusions and depressions. The protrusions act as supports for the placing of microcrystals, and the depressions provide the possibility of deformation and destruction of microcrystals under the action of an increasing vertically acting force, which is applied to the microcrystal through the indenter of the dynamic ultra-micro hardness tester. The moment of destruction of the microcrystals is observed to be dependent on the force on the displacement of the indenter. The measured values of the mechanical strength of CaSO4 microcrystals varied in a range from ∼3.5 to ∼6.0 GPa. The experimental strength values are in good agreement with the values obtained from the results of numerical analysis of the stressed state formed in the volume of CaSO4 microcrystals during the three-point bend test.

Propagation-Invariant Space-Time Plasmonic Pulse in Subwavelength MIM Waveguide.

The metal-insulator-metal (MIM) plasmonic waveguide has been highly anticipated for confining and guiding surface plasmon polaritons (SPPs) on the subwavelength scale. However, perennial drawbacks such as a short propagation length and an unbounded transverse field have set limits on the use of the MIM waveguide in various applications. Herein, diffraction- and dispersion-free MIM modes are synthesized by using space-time wave packets (STWPs) and are therefore referred to as space-time MIM (ST-MIM) waveguide modes. Compared to a Gaussian pulse of the same duration and spectral bandwidth, the ST-MIM demonstrates enhanced propagation lengths of about 2.4 times for the symmetric mode and about 6.3 times for the antisymmetric mode. In the simulations, the ST-MIMs are confined in all transverse dimensions, thereby overriding the diffraction limits. In addition, the group velocities of the ST-MIMs can be arbitrarily designed, which makes it possible to synchronize the pulse propagation speeds of the symmetric and antisymmetric MIM modes.

An In Vivo Study to Compare the Clinical Effectiveness of Clear Retainer Made on a Conventional and a Digitally Fabricated Model Over a Six-Month Period After Debonding.

Background With the advent of 3D printing, many more possibilities have arisen for treatment planning. 3D rapid prototyping has enabled us to see a whole other dimension that has helped us to give the best possible care for our patients. With more and more advancements being made in this subject, it becomes necessary to check the reliability of the equipment and its effectiveness in the management of the problem at hand. This original study was conducted with the aim of checking the accuracy, dimensional stability, and reliability of orthodontic retainers made on a conventional and digitally fabricated model over a six-month period after debonding. Material and methods The patients were selected from those who have completed fixed orthodontic mechanotherapy from the Department of Orthodontics and Dentofacial Orthopaedics, Sri Guru Ram Das Institute of Dental Sciences and Research, Sri Amritsar. Fifty patients received a clear retainer, which was fabricated for the upper and lower arch after removing the brackets. Patients were included in this study irrespective of their age groups.The manual method used a vacuum-forming machine to fabricate six retainers on stone models. In the digital method, new impressions were taken after three months, and digital models were obtained through 3D scanning and printing, followed by clear retainer fabrication. The data were gathered through a systematic process involving manual and digital methods for clear retainer fabrication and subsequent evaluation. The data obtained was computed for statistical evaluation and comparison. Results Mean and standard deviations of conventional (manual) and digital variables in the two groups were calculated. An ANOVA test was used to evaluate statistically significant differences for mesiodistal widthand buccolingual width, and a post hoc Tuckey test was applied for multiple comparisons. The results indicated that most mesiodistal and buccolingual width measurements showed non-significant variations and exhibited a good correlation. Extraction space opening, assessed through an independent t-test for both the maxilla and mandible, also yielded non-significant and comparable results. Additionally, intra-operator and inter-operator measurements using a digital caliper demonstrated high agreement. Intra-class correlation (ICC) values exceeded 0.75, and inter-operator ICC results reflected a high level of agreement ranging from 0.8 to 0.99. Conclusion The primary objective of this study was to establish a correlation between the accuracy, dependability, and clinical efficacy of orthodontic retainers produced using both conventional and digitally created models. This investigation spanned a duration of six months following the removal of orthodontic brackets. The results showed that most of the statistically significant values were due to the inherent potential of the 3D printer for polymerization shrinkage, which, being a stereolithographic 3D printer, had a potential for a slight dimensional shift in the transverse dimension. However, the mean difference between all the models printed was slight and clinically insignificant.

Clinical and multiparametric MRI features for differentiating uterine carcinosarcoma from endometrioid adenocarcinoma

IntroductionThe purpose of our study was to differentiate uterine carcinosarcoma (UCS) from endometrioid adenocarcinoma (EAC) by the multiparametric magnetic resonance imaging (MRI) features.MethodsWe retrospectively evaluated clinical and MRI findings in 17 patients with UCS and 34 patients with EAC proven by histologically. The following clinical and pathological features were evaluated: post- or pre-menopausal, clinical presentation, invasion depth, FIGO stage, lymphaticmetastasis. The following MRI features were evaluated: tumor dimension, cystic degeneration or necrosis, hemorrhage, signal intensity (SI) on T2-weighted images (T2WI), relative SI of lesion to myometrium on T2WI, T1WI, DWI, ADCmax, ADCmin, ADCmean (RSI-T2, RSI-T1, RSI-DWI, RSI-ADCmax, RSI-ADCmin, RSI-ADCmean), ADCmax, ADCmin, ADCmean, the maximum, minimum and mean relative enhancement (RE) of lesion to myometrium on the arterial and venous phases (REAmax, REAmin, REAmean, REVmax, REVmin, REVmean). Receiver operating characteristic (ROC) analysis and the area under the curve (AUC) were used to evaluate prediction ability.ResultsThe mean age of UCS was higher than EAC. UCS occurred more often in the postmenopausal patients. UCS and EAC did not significantly differ in depth of myometrial invasion, FIGO stage and lymphatic metastasis. The anterior-posterior and transverse dimensions were significantly larger in UCS than EAC. Cystic degeneration or necrosis and hemorrhage were more likely occurred in UCS. The SI of tumor on T2WI was more heterogeneous in UCS. The RSI-T2, ADCmax, ADCmean, RSI-ADCmax and RSI-ADCmean of UCS were significantly higher than EAC. The REAmax, REAmin, REAmean, REVmax, REVmin and REVmean of UCS were all higher than EAC. The AUCs were 0.72, 0.71, 0.86, 0.96, 0.89, 0.84, 0.73, 0.97, 0.88, 0.94, 0.91, 0.69 and 0.80 for the anterior-posterior dimension, transverse dimension, RSI-T2, ADCmax, ADCmean, RSI-ADCmax, RSI-ADCmean, REAmax, REAmin, REAmean, REVmax, REVmin and REVmean, respectively. The AUC was 0.997 of the combined of ADCmax, REAmax and REVmax. Our study showed that ADCmax threshold value of 789.05 (10–3mm2/s) can differentiate UCS from EAC with 100% sensitivity, 76.5% specificity, and 0.76 AUC, REAmax threshold value of 0.45 can differentiate UCS from EAC with 88.2% sensitivity, 100% specificity, and 0.88 AUC.ConclusionMultiparametric MRI features may be utilized as a biomarker to distinguish UCS from EAC.

Role of Magnetic Resonance Imaging in the Evaluation of Age- and Gender-Related Changes in the Dimensions of the Pituitary Gland in the Indian Population.

Background MRI is the standard tool for imaging the pituitary gland. MRI is useful in detecting pathological conditions in the pituitary. Changes in the size and shape of the pituitary among different age groups are seen in MRI. Linear growth is seen in the pituitary during puberty except for growth spurts at the 1st, 10th, and 15th years, followed by a decline in pituitary height and cross-sectional area with increasing age. A convex upper margin was seen in females more than in males. There is a shortage of information about pituitary dimensions and volume in various age groups and among both genders in the Indian population. Hence, a study is needed to assess these parameters. Materials and methods A retrospective cross-sectional study was done in the MRI unit of Radiology, Saveetha Medical College and Hospital, Chennai. A total of 200 patients in the age group of 11-80 years who underwent MRI free from neuroendocrine, neurological, and psychiatric disorders were included in this study. Statistical analysis Measurements were made of the pituitary gland's height, volume, and anteroposterior and transverse dimensions. Using SPSS Statistics software (IBM Corp. IBM SPSS Statistics for Windows. Armonk, NY: IBM Corp.), the data was input and examined. The ANOVA test revealed the relationship between anteroposterior dimension, transverse dimension, height, and volume with age. In contrast, an independent t-test determined the association of the same parameters with sex. The Chi-square test was used to assess the association of the shape of the pituitary gland with age and sex. Results Anteroposterior dimension, height, and volume of the pituitary gland were found to be statistically significant with age (p<0.05), but the transverse dimension was not significant with age (p>0.05). However, the independent t-test showed highly significant differences between the anteroposterior dimension in males and females. The shape of the pituitary gland was found to be statistically significant with age and gender. In contrast, the pituitary gland's transverse diameter, height, and volume showed no significance. Conclusion The study helps identify the substantial changes in the pituitary gland during a person's lifespan, which are affected by age and gender. The pituitary height and volume will reflect physiological neuroendocrine differences between younger and older male and female subjects.

Exciting space-time surface plasmon polaritons by irradiating a nanoslit structure.

Space-time (ST) wave packets are propagation-invariant pulsed optical beams that travel freely in dielectrics at a tunable group velocity without diffraction or dispersion. Because ST wave packets maintain these characteristics even when only one transverse dimension is considered, they can realize surface-bound waves (e.g., surface plasmon polaritons at a metal-dielectric interface, which we call ST-SPPs) that have the same unique characteristics as their freely propagating counterparts. However, because the spatiotemporal spectral structure of ST-SPPs is key to their propagation invariance on the metal surface, their excitation methodology must be considered carefully. Using finite-difference time-domain simulations, we show that an appropriately synthesized ST wave packet in free space can be coupled to an ST-SPP via a single nanoscale slit inscribed in the metal surface. Our calculations confirm that this excitation methodology yields surface-bound ST-SPPs that are localized in all dimensions (and can thus be considered as plasmonic "bullets"), which travel rigidly at the metal-dielectric interface without diffraction or dispersion at a tunable group velocity.

Evaluation of maxillary transverse dimensions in individuals with a unilaterally impacted canine.

The aim of this study was to investigate the maxillary width within individuals with a unilaterally impacted maxillary canine and to determine any association between the impacted canine location and some canine-related variables. A cross-sectional analytical study using a split-mouth design included 22 CBCTs of individuals with unilaterally impacted maxillary canines (a total of 44 sides). The maxillary width was measured and compared in both impacted and non-impacted sides at various levels: basal, alveolar, and dental. The following canine-related variables were analyzed and compared with impaction location: impacted canine angulation, cusp tip distance from the occlusal plane, type of impaction (vertical or horizontal), presence of root resorption, deciduous teeth, or adjacent teeth transposition. Significance was considered at P < 0.05. There was a significant reduction in maxillary width on the impacted side at the following levels: maxillary first premolar alveolar crest in both coronal and axial sections, dental width measured from the central fossa of maxillary first molar to the midline, and width measured from the canine cusp tip to the midline. Moreover, the distance from the palatally impacted canine cusp tip to the occlusal plane was statistically significantly lower (7.6 ± 1.5 mm) compared to buccal (10.8 ± 3.3 mm) and mid-alveolus (12.0 ± 3.9 mm) impaction, (P values = 0.02). There was a significant association between canine impaction and reduction in the maxillary width at least on the dental level. The palatally impacted canine cusp tip was significantly closer to the occlusal plane compared to the buccal and mid-alveolar impaction.

Simulation and measurement of the interplay between electron cooling, impedance, intrabeam scattering, and space charge for coasting beams

The Low Energy Ion Ring (LEIR) at CERN is the first synchrotron in the Large Hadron Collider ions injector chain. The performance of LEIR is mainly determined by the number of charges extracted from the machine and transferred to the downstream chain of accelerators. Ions are delivered by the linear accelerator Linac 3. In the intensity accumulation phase, the machine operates with coasting beams: each injected beam is cooled, reducing its transverse dimensions and momentum spread, and brought into a stacking momentum position to allow subsequent injections. In this context, the evolution of the beam parameters for an injected beam under the effects of electron cooling, impedance, intrabeam scattering (IBS), and space charge is of interest in order to optimize the machine working point with respect to the accumulated intensity and to contribute to the understanding of the interplay of the different collective effects. This work describes the advancement in modeling coasting beam dynamics for LEIR accounting for the interplay of electron cooling, impedance, IBS, and space charge. Each effect is presented and progressively included to compute the simulated equilibrium longitudinal Schottky spectrum, which is found in good agreement with the measured one. Published by the American Physical Society 2024

Flexible sensors with zero Poisson's ratio.

Flexible sensors have been developed for the perception of various stimuli. However, complex deformation, usually resulting from forces or strains from multi-axes, can be challenging to measure due to the lack of independent perception of multiaxial stimuli. Herein, flexible sensors based on the metamaterial membrane with zero Poisson's ratio (ZPR) are proposed to achieve independent detection of biaxial stimuli. By deliberately designing the geometric dimensions and arrangement parameters of elements, the Poisson's ratio of an elastomer membrane can be modulated from negative to positive, and the ZPR membrane can maintain a constant transverse dimension under longitudinal stimuli. Due to the accurate monitoring of grasping force by ZPR sensors that are insensitive to curvatures of contact surfaces, rigid robotic manipulators can be guided to safely grasp deformable objects. Meanwhile, the ZPR sensor can also precisely distinguish different states of manipulators. When ZPR sensors are attached to a thermal-actuation soft robot, they can accurately detect the moving distance and direction. This work presents a new strategy for independent biaxial stimuli perception through the design of mechanical metamaterials, and may inspire the future development of advanced flexible sensors for healthcare, human-machine interfaces and robotic tactile sensing.

Anthropometric Indicators of the Proportionality of the Physique of Girls and Boys Living in the Moscow Region

Anthropometric data provide a qualitative and quantitative assessment of the health status of the population. Typically, they are used in clinical practice to assess general health, nutritional adequacy, growth and development of the body. The aim is to conduct a comparative analysis of anthropometric indicators and proportionality of the physique of boys and girls living in Moscow and the Moscow region. Material and methods. The study involved 198 third-year students of the Faculty of Medicine of the State University of Education, over the age of 18, living in Moscow and the Moscow region. The surveyed population did not have either acute or chronic diseases in the stage of decompensation, congenital malformations, ultra-low or excess body weight. An anthropometric study was carried out with measurements of the longitudinal and transverse dimensions of the torso and limbs, calculation of the body mass index, determination of the somatotype and subsequent statistical processing of the data obtained. Conclusion. Anthropometric indicators of girls and boys living in the Moscow region have a number of features. Persons with a mesomorphic somatotype predominate, which indicates the harmonious physical development of boys and girls. Most girls have a transversely narrowed shape of the pelvis, which indicates a possible risk of obstetric complications in the event of pregnancy and childbirth. Otherwise, both boys and girls develop proportionally in accordance with the parameters of the biological and physiological norm.

Occupancy of the Suprascapular Notch by the Suprascapular Nerve: An Anatomic Study

The purpose of the study was to evaluate the dimensions of the suprascapular nerve and the suprascapular notch in freshfrozen cadaveric shoulders and to calculate the occupancy ratio of the notch, i.e. the space occupied by the suprascapular nerve and the superior transverse scapular ligament (STSL). The suprascapular nerve and the suprascapular notch were dissected, and the following parameters were included in the study: presence and shaper of the notch, dimensions of the lower border of the superior transverse scapular ligament and dimensions of the notch and the dimensions of the suprascapular nerve in two directions perpendicular to each other. All measurements were performed using a digital Vernier caliper. The cross-sectional area of the suprascapular nerve was assumed to be elliptical; the area of a U-shaped notch was assumed to be semi-elliptical and the area of the triangular-shaped notch were calculated accordingly. The area of the between the various notch types and the cross-sectional area of the suprascapular nerve in the various notch types were statistically compared. The reliability of continuous measurements was analyzed using intraclass correlation coefficients (ICCs). The suprascapular notch was present in all cases. A U-shaped notch was the most common type (22, 69%) followed by a triangular-shaped notch (10, 31%). The interobserver reliability of the suprascapular nerve and notch dimensions was excellent (ICC = 0.92 and 0.96 respectively). The cross-sectional area of the suprascapular nerve was 5.982.34 mm2 with no difference between the two body sides. The cross-sectional area of the U-shaped suprascapular notch was significantly larger than that of the V-shaped notch (19.98 5.34 mm2 versus 13.777.34 mm2, p=0.02). Correspondingly, the occupancy of the suprascapular notch by the suprascapular nerve was higher in V-shaped rather than U-shaped notches (37.199.34% versus 49.417.32%, p=0.03).

UnBand- Perioprotect palatal connector

The field of orthodontics demands versatility in appliances for faster and efficient treatment process. One such versatile auxiliary used is the Transpalatal arch for anchorage and for active tooth movements such as for correcting molar rotation and up righting, stabilization of posterior transverse dimensions during treatment, and maintenance of leeway spaces during the transition of the dentition.The process of insertion of the Transpalatal arch is cumbersome. To address these limitations, alternative methods for using the Transpalatal arch has been innovated where design experimented does not demand laborious procedures and can be done inhouse and is cost effective.There are three methods custom made Custom made Transpalatal arch is fabricated. Lingual/ Palatal surface of the molar is etched and bonding agent applied and cured. The stub of the TPA is then adapted to the tooth surface and flowable resin is applied and then cured. Preformed mesh is cut and welded onto the lingual sheath thereby converting a weldable lingual sheath into a bondable sheath. Mesh is then adapted onto the prepared tooth surface and then cured with composite. The mesh provides mechanical retention which is helpful for bonding. The custom made Transpalatal arch is now inserted. Vertical and horizontal grooves are made on the posterior side of the lingual sheath using bur. The sheath is then sandblasted to create a rough surface which provides a micromechanical retention area. This sheath is then bonded directly onto the tooth surface and Transpalatal arch inserted. The results suggest that orthodontic appliances without bands are preferable. Bonded TPA’s are less invasive and also requires less chairside time.Bonded TPA’s can overcome these issues and assist both the clinician and the patient in achieving faster orthodontic treatment and reducing discomfort. Therefore, through these innovations, a clinician can judiciously choose based on requirements and employ it effectively in orthodontic treatment.

The Medial Canthus Fibrous Band's Impact on Epicanthal Fold Severity and Classification in Asians: Implications for Epicanthoplasty.

The epicanthal fold (EF) is a semilunar skin fold located in the medial canthus in most Asians. The medial canthus fibrous band (MCFB) reportedly plays a critical role in EF formation. Variations in MCFB shape and size affect the severity and type of EF. We aimed to analyze MCFB variations in different types and severities of EF and explore the effect of the MCFB resection epicanthoplasty technique (MCFB epicanthoplasty). Surgical videos of 40 patients undergoing MCFB epicanthoplasty in our department were reviewed. The MCFB (area), transverse dimension, vertical dimension, upper eyelid direction length (UEDL), and lower eyelid direction length (LEDL) were measured. For aesthetic assessment, 37 patients were followed up for 6 months; intercanthal distance (ICD) and horizontal lid fissure length (HLFL) were measured. Preoperative and postoperative ICD/HLFL ratios were compared. Postoperative scar recovery was evaluated with the Patient and Observer Scar Assessment Scale. Statistical significance was set at P < .05. The MCFB diameter and area were larger for severe EF than for moderate EF (P < .01). Patients with severe EF had larger LEDL than UEDL (P < .01). The tarsalis type had a larger LEDL than the palpebralis type with the same severity (P < .01). MCFB epicanthoplasty yielded favorable postoperative cosmetic effects and scar recovery. Postoperative ICD decreased, while HLFL increased compared to preoperative values (P < .001). The ICD/HLFL ratio was significantly lower postoperatively than preoperatively (P < .001). Postoperative ICD/HLFL ratio was 1.2:1. The MCFB affects the severity and type of EF. MCFB epicanthoplasty effectively corrected moderate to severe EF.

Comparative analysis of the linear dimensions of the ovary, determined using sonography, in an age aspect

Aim of the study was to carry out a comparative analysis of the linear size of the right and left ovaries, determined using sonography in women in adolescence, the elderly, and old age.Material and methods. The study was based on the results of ultrasound examination of 84 women with normal pelvic dimensions who were examined at the gynecology department of the Perm Krai Clinical Hospital during the period 2021–2022 in order to exclude probable pathology of the reproductive system. Measurement of longitudinal (length), transverse (width), and anteroposterior (thickness) dimensions of the ovary was performed using transvaginal access. Women were divided into three groups: the first consisted of 28 adolescents (16 to 20 years old), the second – 29 elderly persons (56 to 74 years old), the third – 27 seniors (75 to 85 years old).Results. When comparing the indicators of ovarian size, their statistically significant decrease by old age was revealed. Right ovary length from adolescence to the old age decreased by 20.56 % (p &lt; 0.01), left – by 28.62 % (p &lt; 0.01). Right ovarian width becomes smaller by 20.87 % (p &lt; 0.01) in elderly age and by 26 % (p &lt; 0.01) in senile age, left – by 20.8 % (p &lt; 0.01) and by 28.32 % (p &lt; 0.01), respectively, the anteroposterior dimension of the right ovary – by 23.2 % (p &lt; 0.01) and by 38.8 % (p &lt; 0.01), of the left ovary – by 31.19 % (p &lt; 0.01) and by 39 % (p &lt; 0.01), respectively.Conclusions. The results obtained allow us to expand our understanding of the features of the age-related structure of the ovaries and further continue their detailed study, since new knowledge is needed to develop modern methods for the prevention of pathology of the female reproductive system and the timely provision of quality medical care.

An analytic model for the flow induced in syringomyelia cavities.

A simple two-dimensional fluid-structure-interaction problem, involving viscous oscillatory flow in a channel separated by an elastic membrane from a fluid-filled slender cavity, is analyzed to shed light on the flow dynamics pertaining to syringomyelia, a neurological disorder characterized by the appearance of a large tubular cavity (syrinx) within the spinal cord. The focus is on configurations in which the velocity induced in the cavity, representing the syrinx, is comparable to that found in the channel, representing the subarachnoid space surrounding the spinal cord, both flows being coupled through a linear elastic equation describing the membrane deformation. An asymptotic analysis for small stroke lengths leads to closed-form expressions for the leading-order oscillatory flow, and also for the stationary flow associated with the first-order corrections, the latter involving a steady distribution of transmembrane pressure. The magnitude of the induced flow is found to depend strongly on the frequency, with the result that for channel flow rates of non-sinusoidal waveform, as those found in the spinal canal, higher harmonics can dominate the sloshing motion in the cavity, in agreement with previous in vivo observations. Under some conditions, the cycle-averaged transmembrane pressure, also showing a marked dependence on the frequency, changes sign on increasing the cavity transverse dimension (i.e. orthogonal to the cord axis), underscoring the importance of cavity size in connection with the underlying hydrodynamics. The analytic results presented here can be instrumental in guiding future numerical investigations, needed to clarify the pathogenesis of syringomyelia cavities.

Skeletal and dental effects of function-generating bite appliance compared to rapid palatal expander and untreated controls.

Maxillary expansion is a fundamental interceptive orthodontic treatment, which can be achieved through either a rapid expansion protocol or functional devices. However, no data exist about the efficacy of functional devices in achieving skeletal expansion. Therefore, the aim of this study was to compare the effects of the rapid palatal expander (RPE) and the function-generating bite type M (FGB-M) on the transversal dimension of the maxilla, and on the maxillary and mandibular dental arch width. One hundred eighty-one skeletal Class I patients, aged between 6 and 12 years and with a cervical vertebral maturation stage II or III, with maxillary transversal deficiency were retrospectively enrolled; among these 55 were treated with FGB-M, 73 were treated with RPE and 51 were untreated subjects retrieved from historical databases. The pre-treatment (T0) and post-treatment (T1) frontal cephalograms were retrieved, and the maxillary and mandibular widths, and the distance between upper and lower first molars were measured. T1-T0 interval was of 17.3 months (RPE), 24.6 months (FGB-M) and 18.2 months (controls). The statistical analysis showed that there were no statistically significant differences between the RPE and FGB-M groups regarding skeletal and dental expansion, while the untreated control group differed significantly from the other two groups. The comparison between patients treated with RPE and FGB-M showed that there were no statistically significant differences between the RPE and FGB-M groups regarding the amount of skeletal expansion and dental arch width, suggesting that both appliances can be used to achieve similar results.