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1.
Am J Orthod Dentofacial Orthop ; 159(5): e423-e437, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33653638

RESUMO

INTRODUCTION: The objective of this research was to evaluate the correlation between 3-dimensional (3D) lip vermilion (LV) morphology and skeletal patterns as well as incisor measurements in young Chinese adults. METHODS: In all, 240 young adults were enrolled; these included 80 patients each with skeletal Class I, Class II, and Class III malocclusions, respectively. Each sagittal skeletal pattern included 40 male and 40 female subjects. Twenty-two 3D LV measurements were obtained from 3D facial scans. Skeletal and incisor measurements were evaluated on lateral cephalograms. Correlation and regression analysis were performed between soft and hard tissue measurements. RESULTS: Six of 22 LV measurements showed significant differences between male and female subjects. The 3D LV morphology showed significant differences with respect to different skeletal patterns and sex. Adults with skeletal Class III malocclusion tended to have thinner upper vermilion and fuller lower vermilion than subjects with skeletal Class II and III malocclusion. The mandibular plane angle negatively correlated with the upper-lower vermilion midsagittal curve length and surface area ratio in adults with skeletal Class I and II malocclusion, yet the vertical facial skeletal type showed no correlation in adults with skeletal Class III malocclusion. The vermilion angle, central bow angle, vermilion height, vermilion midsagittal curve length, vermilion height and width ratio, and vermilion surface area showed a significant correlation with incisor measurements. Regression analysis found that the ANB angle was an important factor affecting the upper and lower vermilion midsagittal curve length and surface area ratio. Further, the vermilion height and height and width ratio were closely correlated with the interincisal (U1/L1) angle, whereas the central bow angle was closely correlated with the maxillary incisor torque. CONCLUSIONS: Most LV morphology variables were correlated to skeletal patterns and incisor measurements. Skeletal Class III malocclusion showed significant differences in vermilion morphology. Both the sagittal and vertical skeletal pattern have effects on vermilion proportion. The incisor torque was closely correlated to vermilion shape and central bow angle and might influence the vermilion esthetics. However, the proportion of the upper and lower vermilion was mainly affected by the ANB angle.


Assuntos
Má Oclusão Classe III de Angle , Má Oclusão Classe II de Angle , Cefalometria , China , Estética Dentária , Feminino , Humanos , Lábio/diagnóstico por imagem , Masculino , Má Oclusão Classe II de Angle/diagnóstico por imagem , Má Oclusão Classe III de Angle/diagnóstico por imagem , Mandíbula/diagnóstico por imagem , Adulto Jovem
2.
Zookeys ; 1190: 1-37, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38298406

RESUMO

A new Chinese ant species Carebaralaevicepssp. nov. is described based on the major and minor workers. This species is most similar to C.lusciosa (Wheeler, 1928) due to a spineless propodeum, the absence of horns, and a smooth head capsule. It is distinguished by the following features: (1) antenna 10-segmented; (2) katepisternum rugose-reticulate; (3) in major workers, lateral sides of head in full-face view parallel; (4) metanotal groove distinct, anterodorsal corner forming an acute tooth behind metanotal groove. Moreover, an updated key to Chinese Carebara species is presented based on major workers, with a checklist comprising a total of 36 Chinese Carebara species and subspecies. Morphological structures and scanning electron micrographs of the newly discovered species' minor and major workers are provided.

3.
Int J Biol Macromol ; 266(Pt 1): 131179, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552698

RESUMO

Collagen (COL) is the most widespread functional protein. Designing and developing dual-dynamic-bond cross-linked COL adhesive hydrogel sealants with multifunctional is highly advantageous for achieving a superior wound closure effect and hemostasis. In this study, we developed hybrid hydrogels consisting of fish-skin COL, oxidized sodium alginate (OSA), borax and polyvinyl alcohol (PVA) to enhance full-thickness wound healing. The hydrogels were furnished with first-rate self-healing capabilities through the dual-dynamic-bond cross-linking of dynamic Schiff base bonds (COL-OSA) and diol boric acid bonds (OSA-borax) with reversible breakage and re-formation. Moreover, the incorporation of PVA stimulated the formation of hydrogen bonds in the system, bolstering the stability of the hydrogel framework. The prepared hydrogel manifests self-healing, injectability, multifunctional adhesiveness and biodegradability. In vivo assessment of the hemostatic capacity of COSP20 hydrogel was superior to gauze both in the mice liver injury model and mice tail amputation model. In addition, a full-thickness skin wound model in mice revealed that the COSP20 hydrogel facilitated faster wound closure by accelerating reepithelialization, COL deposition and angiogenesis. These findings illustrate the potential of hybrid fish-skin COL-based hydrogels to enhance wound healing and promote rapid tissue repair, and provide new possibilities for the effective utilization of marine fishery resources.


Assuntos
Boratos , Colágeno , Peixes , Hemostasia , Hidrogéis , Pele , Cicatrização , Animais , Cicatrização/efeitos dos fármacos , Hidrogéis/química , Hidrogéis/farmacologia , Camundongos , Colágeno/química , Hemostasia/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/lesões , Alginatos/química , Alginatos/farmacologia , Álcool de Polivinil/química
4.
Korean J Orthod ; 49(4): 222-234, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31367577

RESUMO

OBJECTIVE: To investigate the three-dimensional lip vermilion changes after extraction and non-extraction orthodontic treatment in female adult patients and explore the correlation between lip vermilion changes and incisor changes. METHODS: Forty-seven young female adult patients were enrolled in this study (skeletal Class III patients were excluded), including 34 lip-protruding patients treated by extraction of four first premolars (18 patients requiring mini-implants for maximum anchorage control and 16 patients without mini-implants) and 13 patients requiring non-extraction treatment. Nine angles, seven distances, and the surface area of the lip vermilion were measured by using pre- and post-treatment three-dimensional facial scans. Linear and angular measurements of incisors were performed on lateral cephalograms. RESULTS: There were no significant changes in the vermilion measurements in the non-extraction group. The vermilion angle, vermilion height, central bow angle, height/width ratio, and vermilion surface area decreased significantly after the orthodontic treatment in the extraction groups, but the upper/lower vermilion proportion remained unchanged. Significant correlations were found between the changes in incisor position and those in vermilion angles, vermilion height, and surface area. CONCLUSIONS: Extraction of the four first premolars probably produced an aesthetic improvement in lip vermilion morphology. However, the upper/lower vermilion proportion remained unchanged. The variations in the vermilion were closely related to incisor changes, especially the upper incisor inclination changes.

5.
PLoS One ; 13(6): e0198677, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29944661

RESUMO

In order to solve the problem of Meshing Efficiency of spur-face gear sliding friction, a method for calculating the Meshing Efficiency of Spur-Face gear is proposed based on Elastohydrodynamic lubrication (EHL) theory. Through the Tooth Contact Analysis (TCA) and Loaded Tooth Contact Analysis technique (LTCA) method, the meshing process of the Spur-Face gear was simulated. The calculation model of Sliding friction coefficient was established by using non Newtonian quasi steady thermal Elastohydrodynamic lubrication (TEHL) theory, and the calculation model of Meshing Efficiency of Spur-Face gear was established. The influence of input torque and rotational speed on Meshing Efficiency is analyzed. The results show that Sliding friction coefficient is an important factor affecting the Meshing Efficiency of gears. Sliding friction coefficient is not the same at different positions of the tooth surface. Sliding friction coefficient is affected by input speed and input torque. This method provides a theoretical basis for further optimization calculation of Spur-Face gear.


Assuntos
Engenharia/métodos , Fricção , Algoritmos , Simulação por Computador , Elasticidade , Engenharia/instrumentação , Humanos , Hidrodinâmica , Lubrificação , Modelos Químicos
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