Convex Recovery of a Structured Signal from Independent Random Linear Measurements

(1) Background—The aim of the present study was to evaluate the correlation between the temporomandibular joint (TMJ) osseous morphology of normal skeletal pattern individuals with different dental malocclusions by using cone-beam computed tomography (CBCT). (2) Methods—The CBCT images of bilateral TMJs in 67 subjects with skeletal class I and average mandibular angle (26 males and 41 females, age range 20–49 years) were evaluated in this study. The subjects were divided into class I, class II division 1, and class II division 2 according to the molar relationship and retroclination of the maxillary incisors. Angular and linear measurements of TMJ were evaluated and the differences between the groups were statistically analyzed. (3) Results—Intragroup comparisons showed statistical differences for articular eminence inclination, the width of the glenoid fossa, the ratio of the width of the glenoid fossa to the depth of the glenoid fossa, the condylar angle, and the intercondylar angle between the malocclusion groups. The measurements of the glenoid fossa shape showed no significant difference between the left and right sides. Females showed more differences in the morphological parameters of TMJ between the three malocclusion groups than the males. (4) Conclusion—The present study revealed differences in the TMJ osseous morphology between dental class I and class II malocclusions in the normal skeletal pattern.

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Pattern and pace of morphological change due to variable human impact: the case of Japanese macaques

Primates ◽

10.1007/s10329-021-00933-7 ◽

2021 ◽

Author(s):

Madeleine Geiger

Keyword(s):

Body Size ◽

Human Impact ◽

Morphological Variation ◽

Japanese Macaques ◽

Linear Measurements ◽

Skull Shape ◽

Rates Of Change ◽

Animal Populations ◽

Captive Populations ◽

In Captivity

AbstractHuman impact influences morphological variation in animals, as documented in many captive and domestic animal populations. However, there are different levels of human impact, and their influence on the pattern and rate of morphological variation remains unclear. This study contributes to the ongoing debate via the examination of cranial and mandibular shape and size variation and pace of change in Japanese macaques (Macaca fuscata). This species is ideal for tackling such questions because different wild, wild-provisioned, and captive populations have been monitored and collected over seven decades. Linear measurements were taken on 70 skulls from five populations, grouped into three ‘human impact groups’ (wild, wild-provisioned, and captive). This made it possible to investigate the pattern and pace of skull form changes among the human impact groups as well as over time within the populations. It was found that the overall skull shape tends to differ among the human impact groups, with captive macaques having relatively longer rostra than wild ones. Whether these differences are a result of geographic variation or variable human impact, related to nutritional supply and mechanical properties of the diet, is unclear. However, this pattern of directed changes did not seem to hold when the single captive populations were examined in detail. Although environmental conditions have probably been similar for the two examined captive populations (same captive locality), skull shape changes over the first generations in captivity were mostly different. This varying pattern, together with a consistent decrease in body size in the captive populations over generations, points to genetic drift playing a role in shaping skull shape and body size in captivity. In the captive groups investigated here, the rates of change were found to be high compared to literature records from settings featuring different degrees of human impact in different species, although they still lie in the range of field studies in a natural context. This adds to the view that human impact might not necessarily lead to particularly fast rates of change.

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Geometric morphometric investigation of craniofacial morphological change in domesticated silver foxes

Scientific Reports ◽

10.1038/s41598-021-82111-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Timothy M. Kistner ◽

Katherine D. Zink ◽

Steven Worthington ◽

Daniel E. Lieberman

Keyword(s):

Three Dimensional ◽

Cranial Base ◽

Craniofacial Morphology ◽

Wild Populations ◽

Linear Measurements ◽

Skeletal Morphology ◽

Geometric Morphometric ◽

Domestication Syndrome ◽

Morphometric Investigation ◽

Unselected Population

AbstractTo test the effects of domestication on craniofacial skeletal morphology, we used three-dimensional geometric morphometrics (GM) along with linear and endocranial measurements to compare selected (domesticated) and unselected foxes from the Russian Farm-Fox Experiment to wild foxes from the progenitor population from which the farmed foxes are derived. Contrary to previous findings, we find that domesticated and unselected foxes show minimal differences in craniofacial shape and size compared to the more substantial differences between the wild foxes and both populations of farmed foxes. GM analyses and linear measurements demonstrate that wild foxes differ from farmed foxes largely in terms of less cranial base flexion, relatively expanded cranial vaults, and increased endocranial volumes. These results challenge the assumption that the unselected population of foxes kept as part of the Russian Farm-Fox experiment are an appropriate proxy for ‘wild’ foxes in terms of craniofacial morphology and highlight the need to include wild populations in further studies of domestication syndrome to disentangle the phenotypic effects of multiple selection pressures. These findings also suggest that marked increases in docility cannot be reliably diagnosed from shape differences in craniofacial skeletal morphology.

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Estimating Craniofacial Growth Cessation: Comparison of Asymptote- and Rate-Based Methods

The Cleft Palate-Craniofacial Journal ◽

10.1177/10556656211002675 ◽

2021 ◽

pp. 105566562110026

Author(s):

Anna M. Hardin ◽

Ryan P. Knigge ◽

Hee Soo Oh ◽

Manish Valiathan ◽

Dana L. Duren ◽

...

Keyword(s):

Estimation Method ◽

Logistic Models ◽

Careful Consideration ◽

Craniofacial Growth ◽

Craniofacial Anomalies ◽

Linear Measurements ◽

Growth Cessation ◽

Lateral Cephalograms ◽

Males And Females ◽

Important Milestone

Objective: To identify differences between asymptote- and rate-based methods for estimating age and size at growth cessation in linear craniofacial measurements. Design: This is a retrospective, longitudinal study. Five linear measurements were collected from lateral cephalograms as part of the Craniofacial Growth Consortium Study (CGCS). Four estimates of growth cessation, including 2 asymptote- (GCasym, GCerr) and 2 rate-based (GCabs, GC10%) methods, from double logistic models of craniofacial growth were compared. Participants: Cephalometric data from participants in 6 historic longitudinal growth studies were included in the CGCS. At least 1749 individuals (870 females, 879 males), unaffected by craniofacial anomalies, were included in all analyses. Individuals were represented by a median of 11 images between 2.5 and 31.3 years of age. Results: GCasym consistently occurred before GCerr and GCabs consistently occurred before GC10% within the rate-based approaches. The ordering of the asymptote-based methods compared to the rate-based methods was not consistent across measurements or between males and females. Across the 5 measurements, age at growth cessation ranged from 13.56 (females, nasion-basion, GCasym) to 24.39 (males, sella-gonion, GCerr). Conclusions: Adolescent growth cessation is an important milestone for treatment planning. Based on our findings, we recommend careful consideration of specific definitions of growth cessation in both clinical and research settings since the most appropriate estimation method may differ according to patients’ needs. The different methods presented here provide useful estimates of growth cessation that can be applied to raw data and to a variety of statistical models of craniofacial growth.

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Assessment of necessity of neuronavigation in localization of calvarial extra-axial lesions in the setting of limited resources

Chinese Neurosurgical Journal ◽

10.1186/s41016-021-00253-1 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Hussein Soffar ◽

Mohamed F. Alsawy

Keyword(s):

Conventional Method ◽

Linear Measurement ◽

Limited Resources ◽

Linear Measurements ◽

Surgical Interventions ◽

Localization Method ◽

Mean Error ◽

Significant Difference ◽

The Mean ◽

Mean Time

Abstract Background Neuronavigation is a very beneficial tool in modern neurosurgical practice. However, the neuronavigation is not available in most of the hospitals in our country raising the question about its importance in localizing the calvarial extra-axial lesions and to what extent it is safe to operate without it. Methods We studied twenty patients with calvarial extra-axial lesions who underwent surgical interventions. All lesions were preoperatively located with both neuronavigation and the usual linear measurements. Both methods were compared regarding the time consumed to localize the tumor and the accuracy of each method to anticipate the actual center of the tumor. Results The mean error of distance between the planned center of the tumor and the actual was 6.50 ± 1.762 mm in conventional method, whereas the error was 3.85 ± 1.309 mm in IGS method. Much more time was consumed during the neuronavigation method including booting, registration, and positioning. A statistically significant difference was found between the mean time passed in the conventional method and IGS method (2.05 ± 0.826, 24.90 ± 1.334, respectively), P-value < 0.001. Conclusion In the setting of limited resources, the linear measurement localization method seems to have an accepted accuracy in the localization of calvarial extra-axial lesions and it saves more time than neuronavigation method.

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Modelling growth curves of the normal infant’s mandible: 3D measurements using computed tomography

Clinical Oral Investigations ◽

10.1007/s00784-021-03937-1 ◽

2021 ◽

Author(s):

Jan Aart M. Schipper ◽

Manouk J. S. van Lieshout ◽

Stefan Böhringer ◽

Bonnie L. Padwa ◽

Simon G. F. Robben ◽

...

Keyword(s):

Computed Tomography ◽

Growth Models ◽

Normal Growth ◽

Growth Patterns ◽

Ct Scans ◽

Mandibular Ramus ◽

Linear Measurements ◽

Mandibular Growth ◽

Gonial Angle ◽

Mandibular Body

Abstract Objectives Data on normal mandibular development in the infant is lacking though essential to understand normal growth patterns and to discriminate abnormal growth. The aim of this study was to provide normal linear measurements of the mandible using computed tomography performed in infants from 0 to 2 years of age. Material and methods 3D voxel software was used to calculate mandibular body length, mandibular ramus length, bicondylar width, bigonial width and the gonial angle. Intra- and inter-rater reliability was assessed for these measurements. They were found to be sufficient for all distances; intra-class correlation coefficients were all above 0.9. Regression analysis for growth modelling was performed. Results In this multi-centre retrospective study, 109 CT scans were found eligible that were performed for various reasons (e.g. trauma, craniosynostosis, craniofacial abscesses). Craniosynostosis patients had larger mandibular measurements compared to non-craniosynostosis patients and were therefore excluded. Fifty-one CT scans were analysed. Conclusions Analysis showed that the mandible increases more in size vertically (the mandibular ramus) than horizontally (the mandibular body). Most of the mandibular growth occurs in the first 6 months. Clinical relevance These growth models provide insight into normal mandibular development in the first 2 years of life. This reference data facilitates discrimination between normal and abnormal mandibular growth.

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Are linear measurements and computerized volumetric ratios determined from axial MRI useful for diagnosing hydrocephalus in children with tuberculous meningitis?

Child s Nervous System ◽

10.1007/s00381-011-1536-4 ◽

2011 ◽

Vol 28 (1) ◽

pp. 79-85 ◽

Cited By ~ 4

Author(s):

Helga von Bezing ◽

Savvas Andronikou ◽

Ronald van Toorn ◽

Tania Douglas

Keyword(s):

Tuberculous Meningitis ◽

Linear Measurements

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An In Vivo 3D Micro-CT Evaluation of Tooth Movement After the Application of Different Force Magnitudes in Rat Molar

The Angle Orthodontist ◽

10.2319/071308-366.1 ◽

2009 ◽

Vol 79 (4) ◽

pp. 703-714 ◽

Cited By ~ 29

Author(s):

Carmen Gonzales ◽

Hitoshi Hotokezaka ◽

Yoshinori Arai ◽

Tadashi Ninomiya ◽

Junya Tominaga ◽

...

Keyword(s):

Tooth Movement ◽

Three Dimensional ◽

Element Model ◽

Longitudinal Change ◽

Micro Ct ◽

Linear Measurements ◽

Center Of Rotation ◽

Ct Evaluation ◽

Space Width

Abstract Objective: To investigate the precise longitudinal change in the periodontal ligament (PDL) space width and three-dimensional tooth movement with continuous-force magnitudes in living rats. Materials and Methods: Using nickel-titanium closed-coil springs for 28 days, 10-, 25-, 50-, and 100-g mesial force was applied to the maxillary left first molars. Micro-CT was taken in the same rat at 0, 1, 2, 3, 10, 14, and 28 days. The width of the PDL was measured in the pressure and tension sides from 0 to 3 days. Angular and linear measurements were used to evaluate molar position at day 0, 10, 14, and 28. The finite element model (FEM) was constructed to evaluate the initial stress distribution, molar displacement, and center of rotation of the molar. Results: The initial evaluation of PDL width showed no statistical differences among different force magnitudes. Tooth movement was registered 1 hour after force application and gradually increased with time. From day 10, greater tooth movement was observed when 10 g of force was applied. The FEM showed that the center of rotation in the molar is located in the center of five roots at the apical third of the molar roots. Conclusion: The rat's molar movement mainly consists of mesial tipping, extrusion of distal roots, intrusion of mesial root, palatal inclination, and mesial rotation. Although the initial tooth movement after the application of different force magnitudes until day 3 was not remarkably different, 10 g of force produced more tooth movement compared with heavier forces at day 28.

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Cats in the forest: predicting habitat adaptations from humerus morphometry in extant and fossil Felidae (Carnivora)

Paleobiology ◽

10.1666/12001 ◽

2013 ◽

Vol 39 (3) ◽

pp. 323-344 ◽

Cited By ~ 33

Author(s):

Carlo Meloro ◽

Sarah Elton ◽

Julien Louys ◽

Laura C. Bishop ◽

Peter Ditchfield

Keyword(s):

Morphological Variability ◽

Olduvai Gorge ◽

Environmental Predictors ◽

Linear Measurements ◽

Multivariate Statistical ◽

Linear Discriminant ◽

Related Group ◽

Discriminant Analyses ◽

The Stability ◽

The Relationship

Mammalian carnivores are rarely incorporated in paleoenvironmental reconstructions, largely because of their rarity within the fossil record. However, multivariate statistical modeling can be successfully used to quantify specific anatomical features as environmental predictors. Here we explore morphological variability of the humerus in a closely related group of predators (Felidae) to investigate the relationship between morphometric descriptors and habitat categories. We analyze linear measurements of the humerus in three different morphometric combinations (log-transformed, size-free, and ratio), and explore four distinct ways of categorizing habitat adaptations. Open, Mixed, and Closed categories are defined according to criteria based on traditional descriptions of species, distributions, and biome occupancy. Extensive exploratory work is presented using linear discriminant analyses and several fossils are included to provide paleoecological reconstructions.We found no significant differences in the predictive power of distinct morphometric descriptors or habitat criteria, although sample splitting into small and large cat guilds greatly improves the stability of the models. Significant insights emerge for three long-canine cats:Smilodon populator,Paramachairodus orientalis, andDinofelissp. from Olduvai Gorge (East Africa).S. populatorandP. orientalisare both predicted to have been closed-habitat adapted taxa. The false “sabertooth”Dinofelissp. from Olduvai Gorge is predicted to be adapted to mixed habitat. The application of felid humerus ecomorphology to the carnivoran record of Olduvai Gorge shows that the older stratigraphic levels (Bed I, 1.99–1.79 Ma) included a broader range of environments than Beds II or V, where there is an abundance of cats adapted to open environments.

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