Studies on the Upper and Lower Jaw-bones of the Japanese

The taxon Beloniformes represents a heterogeneous group of teleost fishes that show an extraordinary diversity of jaw morphology. I present new anatomical descriptions of the jaw musculature in six selected beloniforms and four closely related species. A reduction of the external jaw adductor (A1) and a changed morphology of the intramandibular musculature were found in many Beloniformes. This might be correlated with the progressively reduced mobility of the upper and lower jaw bones. The needlefishes and sauries, which are characterised by extremely elongated and stiffened jaws, show several derived characters, which in combination enable the capture of fish at high velocity. The ricefishes are characterised by several derived and many plesiomorphic characters that make broad scale comparisons difficult. Soft tissue characters are highly diverse among hemiramphids and flying fishes reflecting the uncertainty about their phylogenetic position and interrelationship. The morphological findings presented herein may help to interpret future phylogenetic analyses using cranial musculature in Beloniformes.

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Bite performance surfaces of three ecologically divergent Iguanidae lizards: relationships with lower jaw bones

Biological Journal of the Linnean Society ◽

10.1093/biolinnean/blz067 ◽

2019 ◽

Vol 127 (4) ◽

pp. 810-825

Author(s):

Monique Nouailhetas Simon ◽

Renata Brandt ◽

Tiana Kohlsdorf ◽

Stevan J Arnold

Keyword(s):

Biomechanical Model ◽

Disruptive Selection ◽

Head Shape ◽

Linear Combinations ◽

Mechanical Advantage ◽

Jaw Bones ◽

Correlational Selection ◽

Lower Jaw ◽

Linear Selection ◽

Non Linear

Abstract Traits that interact to perform an ecologically relevant function are expected to be under multivariate non-linear selection. Using the lower jaw morphology as a biomechanical model, we test the hypothesis that lower jaw bones of lizards are subjected to stabilizing and correlational selection, associated with mechanical advantage and maximum bite force. We used three closely related tropidurine species that differ in size, head shape and microhabitat: Eurolophosaurus nanuzae, Tropidurus hispidus and Tropidurus semitaeniatus. We predicted a common pattern of correlational selection on bones that are part of in-levers or part of the out-lever of the lower jaw. The predicted pattern was found in E. nanuzae and T. hispidus, but this could not be shown to be statistically significant. For T. semitaeniatus, we found significant disruptive selection on a contrast involving the surangular, and also significant directional selection on linear combinations of traits in all species. The results indicate that the non-linear selection on lower jaw bones does not reflect an optimum to enhance mechanical advantage in all species. Divergent functional demands and specific ecological contexts of species seem relevant in shaping patterns of selection on morphology.

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Changes in jaw dimensions and bone density in patients with osteoporosis

Stomatoloski glasnik Srbije ◽

10.2298/sgs0901015p ◽

2009 ◽

Vol 56 (1) ◽

pp. 15-22 ◽

Cited By ~ 1

Author(s):

Srdjan Postic

Keyword(s):

Bone Density ◽

Treatment Method ◽

Radiographic Analysis ◽

Panoramic Radiographs ◽

Jaw Bones ◽

Restorative Treatment ◽

Lower Jaw

Introduction Osteopenia and osteoporosis reduce the density and mass of jaw bones. Aim The aim of this study was to present the methods of radiographic analysis in patients with osteoporosis prior to restorative treatment. Method 127 panoramic radiographs (Kodak, USA) and 39 retroalveolar radiographs (KD 58-R 30?40 mm, USA) were used for the analysis of density (DT II 05 densitometer, England) and dimensions of jaw bones with respect to segments corresponding to bone layers. Results The results of this study indicated statistically significant differences in bone density (p<0.05 and p<0.01) in patients with osteopenia. Bone density was significantly reduced (p<0.01 and p<0.001) in osteoporotic patients, when compared to controls. Significant reductions of edentulous ridges in osteoporotic patients women X=23.05 mm (kV=30.72%) and X=22.85 mm (kV=28.81%), and men X=28.83 (kV=8.55%) as well as X=25.36 (kV=11.43%), were observed. Conclusion Bone density of the upper and lower jaw is reduced in osteoporotic patients. At the very beginning of restorative prosthodontic therapy of osteoporotic patients, retroalveolar radiographs and panoramic radiographs should be obtained. Reference lines should be assigned, contours of the alveolar and edentulous ridges on radiographs should be analysed and bone density assessed.

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Morphology of the jaw, suspensorial, and opercle musculature of Beloniformes and related species (Teleostei: Acanthopterygii), with a special reference to the m. adductor mandibulae complex

10.7287/peerj.preprints.691v2 ◽

2015 ◽

Author(s):

Ingmar Werneburg

Keyword(s):

Related Species ◽

Phylogenetic Analyses ◽

Phylogenetic Position ◽

Closely Related Species ◽

Jaw Bones ◽

Morphological Findings ◽

Lower Jaw ◽

Flying Fishes ◽

Reduced Mobility ◽

Jaw Musculature

The taxon Beloniformes represents a heterogeneous group of teleost fishes that show an extraordinary diversity of jaw morphology. I present new anatomical descriptions of the jaw musculature in six selected beloniforms and four closely related species. A reduction of the external jaw adductor (A1) and a changed morphology of the intramandibular musculature were found in many Beloniformes. This might be correlated with the progressively reduced mobility of the upper and lower jaw bones. The needlefishes and sauries, which are characterised by extremely elongated and stiffened jaws, show several derived characters, which in combination enable the capture of fish at high velocity. The ricefishes are characterised by several derived and many plesiomorphic characters that make broad scale comparisons difficult. Soft tissue characters are highly diverse among hemiramphids and flying fishes reflecting the uncertainty about their phylogenetic position and interrelationship. The morphological findings presented herein may help to interpret future phylogenetic analyses using cranial musculature in Beloniformes.

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STUDY OF STRESS-STRAIN STATE OF MATHEMATICAL MODEL OF JAWS USING THE FINITE-ELEMENTS METHOD

Aspirantskiy Vestnik Povolzhiya ◽

10.17816/2072-2354.2019.19.1.131-139 ◽

2019 ◽

Vol 19 (1-2) ◽

pp. 131-139

Author(s):

D. A Trunin ◽

A. V Revyakin ◽

M. A Postnikov ◽

I. N Kolganov ◽

I. A Zakharova ◽

...

Keyword(s):

Finite Elements ◽

Strain State ◽

Soft Tissues ◽

Finite Elements Method ◽

Stress Strain ◽

Jaw Bones ◽

Stress Strain State ◽

Lower Jaw ◽

Characteristic Features ◽

Bone Structures

This work is devoted to the study of the stress-strain state (SSS) model by using the finite-elements method (FEM) of jaw-bones (the system of lower jaw (LJ) - upper jaw (UJ)) and is the next step in understanding the mechanism of mastication as one of the main functions of the maxillofacial system (MFS). At the same time, reliable information about SSS of the LJ and UJ bones with account of the peculiarities of their anatomical and topographical structure will, firstly, reveal the main regularities of the jaw bone deformations. It will make possible to choose prosthetic appliances that will provide the minimum level of intensity of atrophic processes in supporting tissues and the most favorable biomechanical interaction of bone structures, soft tissues and elements of the prosthetic appliance. The results of mathematical calculations allowed to identify the characteristic features of the deformation and interaction of the LJ and UJ bones, which will ensure a scientifically based choice of those prosthetic appliances contributing to the most prolonged and normal functioning of the maxillofacial system in general.

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Morphology of the jaw, suspensorial, and opercle musculature of Beloniformes and related species (Teleostei: Acanthopterygii), with a special reference to the m. adductor mandibulae complex

10.7287/peerj.preprints.691 ◽

2015 ◽

Author(s):

Ingmar Werneburg

Keyword(s):

Related Species ◽

Phylogenetic Analyses ◽

Phylogenetic Position ◽

Closely Related Species ◽

Jaw Bones ◽

Morphological Findings ◽

Lower Jaw ◽

Flying Fishes ◽

Reduced Mobility ◽

Jaw Musculature

The taxon Beloniformes represents a heterogeneous group of teleost fishes that show an extraordinary diversity of jaw morphology. I present new anatomical descriptions of the jaw musculature in six selected beloniforms and four closely related species. A reduction of the external jaw adductor (A1) and a changed morphology of the intramandibular musculature were found in many Beloniformes. This might be correlated with the progressively reduced mobility of the upper and lower jaw bones. The needlefishes and sauries, which are characterised by extremely elongated and stiffened jaws, show several derived characters, which in combination enable the capture of fish at high velocity. The ricefishes are characterised by several derived and many plesiomorphic characters that make broad scale comparisons difficult. Soft tissue characters are highly diverse among hemiramphids and flying fishes reflecting the uncertainty about their phylogenetic position and interrelationship. The morphological findings presented herein may help to interpret future phylogenetic analyses using cranial musculature in Beloniformes.

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The First Tetrapod Finds from the Devonian (Upper Famennian) of Latvia

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.1994.0027 ◽

1994 ◽

Vol 343 (1305) ◽

pp. 303-328 ◽

Cited By ~ 72

Author(s):

Per Erik Ahlberg ◽

Ervins Luksevics ◽

Oleg Lebedev

Keyword(s):

Upper Devonian ◽

Marginal Tooth ◽

Data Set ◽

Limb Bone ◽

Jaw Bones ◽

Lower Jaw ◽

Dorsal Process ◽

Upper Jaw

Ventastega curonica, from the Upper Famennian Ketleri Formation, is the first tetrapod find from the Upper Devonian of Latvia, and only the fourth adequately represented Devonian tetrapod genus to be described. The taxon is represented by disarticulated cranial and postcranial elements from two localities, Ketleri on the Venta River and Pavari on the Ciecere River. A second tetrapod, represented by a single mandibular fragment, appears to be present at Ketleri. The lower jaw of Ventastega is strikingly primitive in retaining fangs on the coronoid series, but shares many characters with those of other known Devonian tetrapods. Some of these features are interpreted as basal tetrapod synapomorphies; they provide a new data set for the identification of isolated tetrapod jaw fragments, and confirm the (previously disputed) tetrapod status of Metaxygnathus. The upper jaw bones of Ventastega are broadly similar to those of Acanthostega, Ichthyostega and Tulerpeton, as is the narial region. The lateral rostral bone is either very small or absent. A preopercular bone is present in the cheek, and the lacrimal is excluded from the orbit. The palate is closed. Palatine and vomer bear fangs which are set in the marginal tooth row. An isolated iliac blade from Pavari, probably attributable to Ventastega, resembles that of Acanthostega but may not have carried a dorsal process. Two clavicles from Pavari and Ketleri which may also belong to Ventastega are of a typical early tetrapod pattern, similar to Greerpeton but with a broader ventral blade. Non-attributable or doubtfully attributable bones from Ketleri include a probable tetrapod postorbital and a possible limb bone. Ventastega appears to be a tetrapod of the same broad `grade' as Ichthyostega and Acanthostega, but is arguably more primitive than either.

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Analysis of variation of sagittal position of the jaw bones in skeletal class III malocclusion

Vojnosanitetski pregled ◽

10.2298/vsp1212039s ◽

2012 ◽

Vol 69 (12) ◽

pp. 1039-1045

Author(s):

Zdenka Stojanovic ◽

Predrag Nikolic ◽

Angelina Nikodijevic ◽

Jasmina Milic ◽

Milos Duka

Keyword(s):

Cranial Base ◽

Class Iii ◽

Class Iii Malocclusion ◽

Facial Profile ◽

X Ray ◽

Skeletal Class ◽

Jaw Bones ◽

Lower Jaw ◽

Significant Difference ◽

Analysis Of Variation

Background/Aim. Skeletal Class III malocclusion is a discrepancy in the sagittal jaw relationship, due to imbalances in their development and/or position, resulting in the dominant appearance of the lower jaw in facial profile. The aim of this study was to determine variations in the sagittal position of the jaw bones to the cranial base in subjects with skeletal Class III, for the earliest possible diagnosis of malocclusion. Methods. Fifty children and as many adults with skeletal Class III, both sexes, were examined and selected, based on the findings of sagittal interjaw relationship (ANB) ? 0? from the cephalometric analysis of tele-x-ray profile head shots. The subjects were grouped according to age. The first group consisted of children aged 6-12 years, and another group, of adults aged 18-26 years. We measured the angles of maxillary prognathism (SNA), mandibular prognathism (SNB) and ANB. Based on these results, within the respective groups subclassification into the subgroups was done, among which a significant difference measured values was evaluated. In both groups a significant correlation of the determined values was evaluated. Results. An average SNA angle ranged 77.36 ? 3.58 in children and 77.32 ? 4.88 in adults, while an average SNB angle was 79.46 ? 3.91 in the group of children and 81.12 ? 3.76 in adults. An average ANB angle was -2.10 ? 2.07 in children, and -4.00 ? 2.34 in adults. In both groups, a significant correlation between the measured values and a significant difference in the values of all the measured parameters were found between patients from different subgroups (p < 0.01). Conclusion. The most common morphological variation of sagittal position of the upper jaw is its retrognatism, which is equally present in both children and adults. Sagittal position of the lower jaw in most of the adults was prognathic, while mandible prognathism in the children was less present.

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The Morphology of Cross-Beaks and BMP4 Gene Expression in Huiyang Bearded Chickens

Animals ◽

10.3390/ani9121143 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1143

Author(s):

Yuyu Hong ◽

Yuchang Pang ◽

Haiquan Zhao ◽

Siyu Chen ◽

Shuwen Tan ◽

...

Keyword(s):

Genetic Basis ◽

Control Group ◽

Jaw Bones ◽

Lower Jaw ◽

Morphogenetic Protein ◽

Parietal Bones ◽

And Control ◽

The Impact ◽

The Relationship

Bird beaks are important for biological purposes such as food intake, removing parasites, and defining phenotypic attributes. Cross-beaks are a threat to poultry health and are harmful to productivity, wasting some units in the poultry industry. However, there is still limited research on subtypes of cross-beaks and the genetic basis of cross-beaks as well. Here, we described the subtypes of cross-beaks in terms of left or right and upper or lower jaw bones. We evaluated the impact of cross-beaks on craniofacial bones and figured out the relationship between bone morphogenetic protein 4 (BMP4) and the development of craniofacial bones in Huiyang bearded chickens. We identified five typical subtypes of cross-beaks by morphological assessment and X-ray scanning. We found that cross-beaks caused certain changes in the facial bone morphology, including changes to the length and width of the bone around the ocular area (p < 0.05). The relative expressions of BMP4 in lacrimal, mandible, premaxilla, frontal, and parietal bones were significantly higher in the severe cross-beak group, followed by that of the medium cross-beak group, weak cross-beak group, and control group (p < 0.05). Overall, we constructed a generally applicable method to classify cross-beaks in term of the angle. The skeleton around the ocular area was affected by the cross-beak. The expression levels of BMP4 in craniofacial bones may provide insight to potential role of BMP4 in the development of cross-beaks.

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Clinical and X-ray diagnostic criteria for maxillofacial damage in children with juvenile limited scleroderma

Rossiyskiy Vestnik Perinatologii i Pediatrii (Russian Bulletin of Perinatology and Pediatrics) ◽

10.21508/1027-4065-2020-65-2-71-79 ◽

2020 ◽

Vol 65 (2) ◽

pp. 71-79

Author(s):

A. A. Skakodub ◽

N. А. Geppe ◽

O. I. Admakin ◽

E. S. Chepurnova ◽

A. A. Mamedov ◽

...

Keyword(s):

Permanent Teeth ◽

X Ray ◽

Jaw Bones ◽

Treatment And Prevention ◽

Lower Jaw ◽

Diagnostic Signs ◽

Limited Scleroderma ◽

Methods Of Treatment ◽

Juvenile Scleroderma ◽

Selection Of

The objective of our study was to improve the diagnosis of maxillofacial lesions in children with juvenile scleroderma. We performed a dental examination of 41 children from 4 to 17 years old with juvenile scleroderma. Based on the clinical X-ray examination we identified the main diagnostic signs of the maxillofacial damage in children with juvenile scleroderma, including partial hemiatrophy, plaque or linear facial lesions, reduced salivation, atrophic glossitis, plaque spots of mucous tongue atrophy, ischemia or shortening of the sublingual bridle, local recession of the gums of the lower jaw, dystopia and tooth supraposition, disocclusion, delay teething, spontaneous resorption of the permanent teeth roots, one-sided delay in the development of jaw bones. Using this complex of symptoms a dentist at the first visit can pre-diagnose scleroderma, which is especially important for the selection of adequate methods of treatment and prevention.

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