Marginal tooth-bearing bones in the lower jaw of the recent australian lungfish,Neoceratodus forsteri (Osteichthyes, Dipnoi)

1995 ◽  
Vol 225 (3) ◽  
pp. 345-355 ◽  
Author(s):  
A. Kemp
Keyword(s):  
Marginal Tooth ◽  
Lower Jaw ◽  
Australian Lungfish

The relationships of Uronemus : A Carboniferous dipnoan with highly modified tooth plates

1987 ◽  
Vol 317 (1185) ◽  
pp. 299-327 ◽  
Keyword(s):  
Tissue Type ◽  
Close Relative ◽  
Marginal Tooth ◽  
Thin Sections ◽  
Scanning Electron Microscope Study ◽  
Air Breathing ◽  
Dental Tissues ◽  
Lower Jaw ◽  
Tooth Plate ◽  
Evolutionary Phase

Previous accounts of the dentition of the Carboniferous dipnoan Uronemus have stressed the significance of the scattered small denticles. These, together with the marginal teeth and ridges, have been interpreted as primitive characters of the dipnoan dentition shared with three other genera: the Devonian Uranolophus and Griphognathus and the Carboniferous to Permian Conchopoma . Genera with tooth plates have been considered to be a monophyletic group in which tooth plates are a derived character; Uronemus has been excluded from this group in all previous investigations dealing with the significance of the dentition for determining relationships among dipnoans. The macromorphology of the dentition of Uronemus has been re-examined and correlated with the histology of all the dental tissues. Optical study of thin sections and scanning electron microscope study of the adjacent cut surfaces has shown that the hard, wear-resistant dentine of the teeth and ridges is petrodentine. The arrangement, growth, wear and histology of the dental tissues have been compared with those of denticulated and tooth-plated genera. The arrangement of new teeth relative to the tooth ridge, the pattern of wear along the ridge, and the type of dentine and its growth indicate that the dentition of Uronemus is best interpreted as a tooth plate with one long lingual tooth ridge and reduced lateral tooth rows. Therefore the marginal tooth ridges are not considered to be homologous with those of denticulate dipnoans such as Uranolophus . The presence of petrodentine, a tissue type only found in forms with tooth plates, is consistent with the view that the dentition is derived by modification of a radiate tooth plate. The denticles covering restricted regions of the palate and lower jaw are considered to have been a secondary acquisition. The suggestion that Conchopoma is a close relative of Uronemus is not accepted, and possible new relationships have been proposed. New data on Scaumenacia and Phaneropleuron , two other genera previously compared with Uronemus , are presented. Rhinodipterus , a form with elongate lingual ridges, is also discussed. Phaneropleuron is shown to have radiate tooth plates and not a marginal row of conical teeth as previously described. It is proposed that the tooth plate of Uronemus is derived from a dipterid type of plate. A discussion of some of the other factors involved in determining the relationships of the genus is given. From an examination of the use of the tongue for respiration and feeding by the extant Lepidosiren paradoxa , it is concluded that many features of dipnoan evolution in the tooth-plated lineage result from the adoption of air breathing after an early evolutionary phase of gill respiration, and that Uronemus was adapted for air breathing. The ‘denticulated’ lineage, which included genera such as Uranolophus and Griphognathus , shows none of the skeletal features associated with the presence of a tongue, and presumably did not become air breathing.

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

1994 ◽  
Vol 343 (1305) ◽  
pp. 303-328 ◽  
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.

scholarly journals Spatial and temporal pattern for the dentition in the Australian lungfish revealed with sonic hedgehog expression profile

2008 ◽  
Vol 276 (1657) ◽  
pp. 623-631 ◽  
Author(s):  
Moya M Smith ◽  
Masataka Okabe ◽  
Jean Joss
Keyword(s):  
Sonic Hedgehog ◽  
Temporal Order ◽  
Developmental Process ◽  
Cichlid Fish ◽  
Sister Group ◽  
Treatment Results ◽  
Lower Jaw ◽  
Left And Right ◽  
Jaw Position ◽  
Australian Lungfish

We report a temporal order of tooth addition in the Australian lungfish where timing of tooth induction is sequential in the same pattern as osteichthyans along the lower jaw. The order of tooth initiation in Neoceratodus starts from the midline tooth, together with left and right ones at jaw position 2, followed by 3 and then 1. This is the pattern order for dentary teeth of several teleosts and what we propose represents a stereotypic initiation pattern shared with all osteichthyans, including the living sister group to all tetrapods, the Australian lungfish. This is contrary to previous opinions that the lungfish dentition is otherwise derived and uniquely different. Sonic hedgehog ( shh ) expression is intensely focused on tooth positions at different times corresponding with their initiation order. This deployment of shh is required for lungfish tooth induction, as cyclopamine treatment results in complete loss of these teeth when applied before they develop. The temporal sequence of tooth initiation is possibly regulated by shh and is know to be required for dentition pattern in other osteichthyans, including cichlid fish and snakes. This reflects a shared developmental process with jawed vertebrates at the level of the tooth module but differs with the lack of replacement teeth.

Successful radiation therapy for primary cutaneous follicle center lymphoma

2019 ◽  
Vol 8 (2) ◽  
Author(s):  
Takashi Matsushita ◽  
Tomoyasu Kumano ◽  
Kazuhiko Takehara
Keyword(s):  
Radiation Therapy ◽  
Skin Biopsy ◽  
B Cell ◽  
B Cell Lymphomas ◽  
Solitary Lesion ◽  
Lower Jaw ◽  
First Choice ◽  
The Right

Primary cutaneous follicle center lymphoma (PCFCL) accounts for the majority of primary cutaneous B-cell lymphomas. We report a 60-year-old womanwith PCFCL. She had a red nodule (25 × 25 mm) on the right side of the lower jaw. She was diagnosed with PCFCL by skin biopsy. And then, she was treated with radiation therapy (total 30.6 Gy), which completely eliminated the nodule. Our case suggests that radiation therapy may be a first choice for PCFCL patients with a solitary lesion or localized lesions.    

Jaw Apparatus and Feeding Mechanics of Typhlops (Ophidia: Typhlopidae): a Reconsideration

2011 ◽  
Vol 4 (2) ◽  
pp. 120-127 ◽  
Author(s):  
Nikolai N. Iordansky
Keyword(s):  
Lower Jaw ◽  
Jaw Apparatus ◽  
Feeding Mechanics ◽  
Cranial Kinesis

The cranial kinesis and movements of the lower jaw in Typhlops are analyzed, with special emphasis placed on the functions of the jugomandibular ligament. The musculature of the Typhlops jaw apparatus is described. The role of movements of the quadrato-mandibular and palato-maxillary systems in feeding mechanics and functioning of the jaw apparatus muscles is discussed.

Cephalometric features of connective tissue dysplasia manifestation in children and adolescents

2020 ◽  
Vol 20 (3) ◽  
pp. 174-183 ◽  
Author(s):  
B. N. Davydov ◽  
D. A. Domenyuk ◽  
S. V. Dmitrienko ◽  
T. A. Kondratyeva ◽  
Yu. S. Harutyunyan
Keyword(s):  
Connective Tissue ◽  
Morphological Features ◽  
Short Branch ◽  
Lower Jaw ◽  
Carious Lesions ◽  
High Prevalence ◽  
Care Facilities ◽  
The Face ◽  
Connective Tissue Dysplasia ◽  
Brain Parts

Relevance. The high prevalence of dysplastic disorders involving connective tissue, and its negative effecton the development of dentoalveolar anomalies, carious and non-carious lesions of the teeth, periodontopathy, temporomandibular joint issues in the child population, lay the basis for improving diagnostics algorithms. Enhancing the already available standards is of greatest importance for children at the initial stages of diagnostics when evaluating the external signs of dysplastic disorders.Purpose – improving diagnostics algorithms for connective tissue dysplasia (CTD) in children in primary dental care facilities based on the evaluation of external phenotype signs and maxillofacial morphological features.Materials and methods. Depending on the external phenotype manifestations severity, as well as on laboratory, clinical and instrumental signs, the 92 children with CTD were divided into groups with mild, moderate and severe degrees of undifferentiated dysplasia. Gnathometric and biometric examinations of the maxillofacial area were performed through traditional methods, whereas the diagnosis was set following the generally accepted classifications. The diagnosis confirmation implied evaluation through cone beam computed imaging.Results. The nature and the intensity of morphofunctional disorders in the craniofacial structures (“small” stigmas) depend on the severity of connective tissue dysplastic disorders.Conclusions. The change direction vector in the facial and brain parts of cranium in children with CTD is aimed at increasing hypoplastic tendencies and dolichocephalia, proof to that being the following constitutional and morphological features: the prevalence of the vertical type of face skeleton growth over the horizontal and neutral ones; a convex face profile with a disproportionate general heights of the face skeleton; reduction of latitudinal with an increase in altitude facial parameters; a narrow short branch of the lower jaw; the upper jaw displaced downwards and forward; a decrease in the size of the apical basis of the lower dentition, the lower jaw body, as well as the height and width of the lower jaw branches. 

A STUDY ON CLINICAL AND X - RAY FEATURES OF PARTIALLY  EDENTULOUS PATIENTS WITH DENTAL IMPLANT

2011 ◽  
pp. 96-103
Author(s):  
Quang Hai Nguyen ◽  
Toai Nguyen
Keyword(s):  
Dental Implants ◽  
Dental Implant ◽  
Tooth Loss ◽  
Permanent Teeth ◽  
Missing Teeth ◽  
X Ray ◽  
Lower Jaw ◽  
Molar Teeth ◽  
Edentulous Patients ◽  
Missing Tooth

1. Background: Loss of permanent teeth is very common, affected chewing function, speech and aesthetics; restoration of missing teeth with dental implant has several advantages, but we need thoroughly study the clinical and X ray features at the position at missing teeth, then to select the type of implant and make the best plan for the dental implant patients. 2. Materials and method: Cross-section descriptive study. From January 2009 to November 2010, study with 56 patients with 102 implants of MIS and Megagen systems at the Faculty of Odonto-Stomatology, Hue College of Medicine and Pharmacy and Vietnam-Cuba Hospital in Ha Noi. 3. Results: Distributed equally in male and female, common ages 40 – 59 (55,4%), the majority of missing teeth occurs in the lower jaw (63,8%) and especially, the teeth 36 and 46 (25,4%). The majority of missing teeth due to dental caries, dental pulp and apical diseases (64,7%) of the molar teeth (51,9%); the most position of missing tooth have enough bone for dental implants (87,3%), time of tooth loss and bone status in the position of tooth loss are related to each other (p < 0,01). Diameter and length of implant usually used 4.0 – 6.0 mm (63,7%) and 8.5 – 13.0 mm (83,3%). 4. Conclusion: Clinical and X ray features of edentulous patients has an important role in determining the type of implants and treatment planning of dental implants. Key words: Loss of permanent teeth, X ray and clinical features, Dental implant.

THE PROGNOSTIC VALUE OF PD-L1 EXPRESSION IN TUMOR AND IMMUNE CELLS IN SQUAMOUS CELL CARCINOMA OF THE ORAL MUCOSA

2017 ◽  
Vol 63 (5) ◽  
pp. 759-765
Author(s):  
Svetlana Kutukova ◽  
Natalya Belyak ◽  
Grigoriy Raskin ◽  
Marina Mukhina ◽  
Georgiy Manikhas ◽  
...  
Keyword(s):  
Oral Mucosa ◽  
Malignant Tumor ◽  
Immune Cells ◽  
Prognostic Value ◽  
Hard Palate ◽  
Malignant Tumors ◽  
Small Cell ◽  
Alveolar Process ◽  
Small Cell Lung ◽  
Lower Jaw

The most frequent of malignant tumor cites of the oral mucosa are tongue - 55 %, mucosa of the cheek - 12 %, the fundus of the oral cavity - 10 %, the alveolar process of the upper jaw and the hard palate - 9 %, the alveolar process of the lower jaw - 6 %, the soft palate - 2 %. Malignant tumor cells carry PD-L1 ligands on their surface and its expression level is often correlated with an unfavorable prognosis in particular for such tumors as melanoma, kidney cancer and non-small cell lung cancer. It is relevant to evaluate the correlation between overexpression of PD-L1 and overall survival in patients with malignant tumors of the oral mucosa.

scholarly journals Modelling of the stress-strain state of the lower jaw

2021 ◽  
Vol 1029 ◽  
pp. 012071
Author(s):  
A V Avilov ◽  
N V Avilova ◽  
E S Tananakina ◽  
E V Sadyrin
Keyword(s):  
Strain State ◽  
Stress Strain ◽  
Stress Strain State ◽  
Lower Jaw
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