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1.
Head Face Med ; 16(1): 12, 2020 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-32487178

RESUMO

BACKGROUND: Ameloblastoma is one of the most common benign odontogenic neoplasms. Its surgical excision has the potential to lead to postoperative malocclusion. In this case report, we describe the successful interdisciplinary orthodontic treatment of a patient with ameloblastoma who underwent marginal mandibulectomy. CASE PRESENTATION: A woman of 20-year-old was diagnosed with ameloblastoma, and underwent marginal mandibulectomy when she was 8 years of age. She had an excessive overjet (11.5 mm) and a mild open bite (- 1.5 mm) with a severely resorbed atrophic edentulous ridge in the area around the mandibular left lateral incisor, canine and first premolar. An alveolar bone defect associated with tumor resection was regenerated by vertical distraction osteogenesis (DO). Subsequently, 3 dental implants were placed into the reconstructed mandible. Orthodontic treatment using implant-anchored mechanics provided a proper facial profile with significantly improved occlusal function. The occlusion appeared stable for a 7-year retention period. CONCLUSIONS: These results suggest that surgically assisted and implant anchored-orthodontic approaches might be effective for the correction of such malocclusions.

2.
Eur J Orthod ; 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32346737

RESUMO

BACKGROUND AND OBJECTIVES: The masticatory force affects craniofacial development. We aimed to quantify the topological deviation of the growing craniofacial structure due to soft-food diet feeding and to map the region where the phenotypes appeared on three-dimensional (3D) images. MATERIAL AND METHODS: Mice were fed a powdered soft diet (SD) or conventional hard diet (HD) of regular rodent pellets at 3 weeks of age until 9 weeks of age. The heads, excluding the mandibles, were scanned by micro-computed tomography. The topographic deviation of the bony surface was quantitatively assessed by a wire mesh fitting analysis. The actual displacement and significant differences were mapped and visualized in each x-, y-, and z-axis on the 3D craniofacial image. On these reconstructed images, two-dimensional linear measurements between the landmark points confirmed the 3D skeletal displacement. RESULTS: In the transverse direction, the zygomatic arches and the region in which the temporal muscle attaches to the parietal and temporal bones were narrow in the SD group. The temporal muscle attachment regions significantly shifted anteriorly, and consequently, the sagittal zygomatic arch shortened. Although the cranial sagittal length was not affected, the vertical height was also reduced in the SD group compared to the HD group. CONCLUSIONS: Our 3D surface-based analysis demonstrated that SD feeding resulted in reduced 3D bony development at the region where the chewing muscles attach to the zygomatic arches and the temporal and parietal bones. Interestingly, SD feeding induced an anterior shift in the temporal and parietal bone regions, which can affect the skeletal inter-jaw relationship.

3.
Int J Mol Sci ; 21(8)2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32316324

RESUMO

To identify proteins that cooperate with cellular communication network factor 2 (CCN2), we carried out GAL4-based yeast two-hybrid screening using a cDNA library derived from the chondrocytic cell line HCS-2/8. Rab14 GTPase (Rab14) polypeptide was selected as a CCN2-interactive protein. The interaction between CCN2 and Rab14 in HCS-2/8 cells was confirmed using the in situ proximity ligation assay. We also found that CCN2 interacted with Rab14 through its IGFBP-like domain among the four domains in CCN2 protein. To detect the colocalization between CCN2 and Rab14 in the cells in detail, CCN2, wild-type Rab14 (Rab14WT), a constitutive active form (Rab14CA), and a dominant negative form (Rab14DN) of Rab14 were overexpressed in monkey kidney-tissue derived COS7 cells. Ectopically overexpressed Rab14 showed a diffuse cytosolic distribution in COS7 cells; however, when Rab14WT was overexpressed with CCN2, the Rab14WT distribution changed to dots that were evenly distributed within the cytosol, and both Rab14 and CCN2 showed clear colocalization. When Rab14CA was overexpressed with CCN2, Rab14CA and CCN2 also showed good localization as dots, but their distribution was more widespread within cytosol. The coexpression of Rab14DN and CCN2 also showed a dotted codistribution but was more concentrated in the perinuclear area. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis revealed that the reduction in RAB14 or CCN2 mRNA by their respective siRNA significantly enhanced the expression of ER stress markers, BIP and CHOP mRNA in HCS-2/8 chondrocytic cells, suggesting that ER and Golgi stress were induced by the inhibition of membrane vesicle transfer via the suppression of CCN2 or Rab14. Moreover, to study the effect of the interaction between CCN2 and its interactive protein Rab14 on proteoglycan synthesis, we overexpressed Rab14WT or Rab14CA or Rab14DN in HCS-2/8 cells and found that the overexpression of Rab14DN decreased the extracellular proteoglycan accumulation more than the overexpression of Rab14WT/CA did in the chondrocytic cells. These results suggest that intracellular CCN2 is associated with Rab14 on proteoglycan-containing vesicles during their transport from the Golgi apparatus to endosomes in chondrocytes and that this association may play a role in proteoglycan secretion by chondrocytes.

4.
Dental Press J Orthod ; 25(1): 36-46, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32215476

RESUMO

INTRODUCTION: Tooth agenesis is one of the most common dental anomalies; however, the concomitant occurrence of opposite dental numerical variation of hypohyperdontia is extremely rare. OBJECTIVE: To report the successful orthodontic management of a patient with non-syndromic concomitant bilateral agenesis of mandibular canines and two midline inverted supernumerary maxillary teeth. CASE REPORT: 21-year-old female patient with a chief complaint of protrusive right maxillary central incisor. The patient was diagnosed with a mild Class II skeletal base, Angle Class III molar relationship and increased overjet associated with hypohyperdontia. Anterior open bite accompanied with tongue-thrusting habit were also observed. Two temporary anchorage devices (TADs) were implanted at the buccal side of the maxillary molar region to control vertical height. Anterior teeth retraction was done after extraction of the maxillary first premolars, to improve the excessive overjet. The treatment mechanics involved lingual brackets system for the maxillary arch and transpalatal arch for anchorage control. RESULTS: The total active treatment period was 35 months. Acceptable occlusion with increased bite force and contact area as well as functional excursion were established without interference, following complex orthodontic treatment with premolar substitution. The resultant occlusion and a satisfactory facial profile were maintained after 29 months of retention. CONCLUSION: The present case report provides implications regarding the orthodontic treatment of hypohyperdontia-associated substitution for missing teeth as an effective option for improving aesthetic and functional aspects.


Assuntos
Má Oclusão de Angle Classe II , Procedimentos de Ancoragem Ortodôntica , Adulto , Cefalometria , Estética Dentária , Feminino , Humanos , Técnicas de Movimentação Dentária , Adulto Jovem
5.
Dental press j. orthod. (Impr.) ; 25(1): 36-46, Jan.-Feb. 2020. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-1089832

RESUMO

ABSTRACT Introduction: Tooth agenesis is one of the most common dental anomalies; however, the concomitant occurrence of opposite dental numerical variation of hypohyperdontia is extremely rare. Objective: To report the successful orthodontic management of a patient with non-syndromic concomitant bilateral agenesis of mandibular canines and two midline inverted supernumerary maxillary teeth. Case report: 21-year-old female patient with a chief complaint of protrusive right maxillary central incisor. The patient was diagnosed with a mild Class II skeletal base, Angle Class III molar relationship and increased overjet associated with hypohyperdontia. Anterior open bite accompanied with tongue-thrusting habit were also observed. Two temporary anchorage devices (TADs) were implanted at the buccal side of the maxillary molar region to control vertical height. Anterior teeth retraction was done after extraction of the maxillary first premolars, to improve the excessive overjet. The treatment mechanics involved lingual brackets system for the maxillary arch and transpalatal arch for anchorage control. Results: The total active treatment period was 35 months. Acceptable occlusion with increased bite force and contact area as well as functional excursion were established without interference, following complex orthodontic treatment with premolar substitution. The resultant occlusion and a satisfactory facial profile were maintained after 29 months of retention. Conclusion: The present case report provides implications regarding the orthodontic treatment of hypohyperdontia-associated substitution for missing teeth as an effective option for improving aesthetic and functional aspects.


RESUMO Introdução: A agenesia é uma das anomalias dentárias mais comuns; porém, a ocorrência concomitante de variações numéricas do tipo hipo-hiperdontia em ambas as arcadas é extremamente rara. Objetivo: Descrever o tratamento ortodôntico bem-sucedido de uma paciente não sindrômica que apresentava agenesia bilateral dos caninos inferiores e dois dentes supranumerários na região de linha média superior. Descrição: Paciente do sexo feminino com 21 anos de idade, apresentando queixa principal de protrusão dos incisivos centrais superiores. Foi diagnosticada com leve Classe II esquelética, relação de molares em Classe III de Angle, sobressaliência aumentada e hipo-hiperdontia. Além disso, a paciente apresentava mordida aberta anterior associada ao hábito de interposição lingual. Dois dispositivos de ancoragem temporária (DATs) foram instalados por vestibular na região dos molares superiores, para controle vertical. A retração dos dentes anteriores foi feita após a extração dos primeiros pré-molares superiores, para reduzir a sobressaliência acentuada. A mecânica adotada envolveu o uso de braquetes linguais na arcada superior e barra transpalatina para controle da ancoragem. Resultados: Após 35 meses de fase ativa desse tratamento complexo, com substituição dos pré-molares, obteve-se oclusão aceitável, com aumento da força oclusal e da área de contatos oclusais, bem como movimentos excursivos funcionais bem estabelecidos e sem interferências. Após 29 meses de contenção, verificou-se estabilidade da oclusão e do perfil facial. Conclusão: Esse relato de caso clínico mostra que o tratamento ortodôntico com substituição de dentes ausentes associados à hipo-hiperdontia é uma opção efetiva para a melhora dos aspectos estéticos e funcionais.

6.
Anat Sci Int ; 95(2): 202-208, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31732869

RESUMO

Retinoic acid (RA), an active metabolite of vitamin A, plays pivotal roles in a wide variety of biological processes, such as body patterning, organ development, and cell differentiation and proliferation. RA signaling is mediated by nuclear retinoic acid receptors, α, ß, and γ (RARα, RARß, and RARγ). RA is a well-known regulator of cartilage and skeleton formation and RARs are also essential for skeletal growth and hypertrophic chondrocyte-specific gene expression. These important roles of RA and RARs in chondrogenesis have been widely investigated using in vivo mouse models. However, few reports are available on the function of each subtype of RARs on in vitro chondrocyte differentiation. Here, we examined the effect of specific agonists of RARs on chondrogenic differentiation of ATDC5 and C3H10T1/2 cells. Subtype-specific RAR agonists as well as RA decreased the expressions of chondrogenic differentiation marker genes and inhibited chondrogenic differentiation, which was accompanied with morphological change to spindle-shaped cells. Among RAR agonists, RARα and RARγ agonists revealed a strong inhibitory effect on chondrogenic differentiation. RARα and RARγ agonists also hampered viability of ATDC5 cells. These observations suggested that RARα and RARγ are dominant receptors of RA signaling that negatively regulate chondrogenic differentiation.

7.
FASEB J ; 33(9): 10409-10424, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31238000

RESUMO

Human periodontal ligament (hPDL) fibroblasts are thought to receive mechanical stress (MS) produced by orthodontic tooth movement, thereby regulating alveolar bone remodeling. However, the role of intracellular calcium ([Ca2+]i)-based mechanotransduction is not fully understood. We explored the MS-induced [Ca2+]i responses both in isolated hPDL fibroblasts and in intact hPDL tissue and investigated its possible role in alveolar bone remodeling. hPDL fibroblasts were obtained from healthy donors' premolars that had been extracted for orthodontic reasons. The oscillatory [Ca2+]i activity induced by static compressive force was measured by a live-cell Ca2+ imaging system and evaluated by several feature extraction method. The spatial pattern of cell-cell communication was investigated by Moran's I, an index of spatial autocorrelation and the gap junction (GJ) inhibitor. The Ca2+-transporting ionophore A23187 was used to further investigate the role of [Ca2+]i up-regulation in hPDL cell behavior. hPDL fibroblasts displayed autonomous [Ca2+]i responses. Compressive MS activated this autonomous responsive behavior with an increased percentage of responsive cells both in vitro and ex vivo. The integration, variance, maximum amplitude, waveform length, and index J in the [Ca2+]i responses were also significantly increased, whereas the mean power frequency was attenuated in response to MS. The increased Moran's I after MS indicated that MS might affect the pattern of cell-cell communication via GJs. Similar to the findings of MS-mediated regulation, the A23187-mediated [Ca2+]i uptake resulted in the up-regulation of receptor activator of NF-κB ligand (Rankl) and Sost along with increased sclerostin immunoreactivity, suggesting that [Ca2+]i signaling networks may be involved in bone remodeling. In addition, A23187-treated hPDL fibroblasts also showed the suppression of osteogenic differentiation and mineralization. Our findings suggest that augmented MS-mediated [Ca2+]i oscillations in hPDL fibroblasts enhance the production and release of bone regulatory signals via Rankl/Osteoprotegerin and the canonical Wnt/ß-catenin pathway as an early process in tooth movement-initiated alveolar bone remodeling.-Ei Hsu Hlaing, E., Ishihara, Y., Wang, Z., Odagaki, N., Kamioka, H. Role of intracellular Ca2+-based mechanotransduction of human periodontal ligament fibroblasts.

8.
J Biomed Mater Res A ; 107(5): 1021-1030, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30675987

RESUMO

In vitro synthesis of bone tissue has been paid attention in recent years; however, current methods to fabricate bone tissue are still ineffective due to some remaining gaps in the understanding of real in vivo bone formation process, and application of the knowledge in bone synthesis. Therefore, the objectives of this study were first, to perform a systematic and ultrastructural investigation of the initial mineral formation during intramembranous ossification of mouse calvaria from a material scientists' viewpoint, and to develop novel mineralization methods based on the in vivo findings. First, the very initial mineral deposition was found to occur at embryonic day E14.0 in mouse calvaria. Analysis of the initial bone formation process showed that it involved the following distinct steps: collagen secretion, matrix vesicle (MV) release, MV mineralization, MV rupture, and collagen fiber mineralization. Next, we performed in vitro mineralization experiments using MVs and hydrogel scaffolds. Intact MVs embedded in collagen gel did not mineralize, whereas, interestingly, MV nanofragments obtained by ultrasonication could promote rapid mineralization. These results indicate that mechanically ruptured MV membrane can be a promising material for in vitro bone tissue synthesis. © 2019 The Authors. journal Of Biomedical Materials Research Part A Published By Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1021-1030, 2019.

9.
J Bone Miner Metab ; 37(4): 614-626, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30413886

RESUMO

This study aimed to predict the key genes and pathways that are activated when different types of mechanical loading are applied to osteocytes. mRNA expression datasets (series number of GSE62128 and GSE42874) were obtained from Gene Expression Omnibus database (GEO). High gravity-treated osteocytic MLO-Y4 cell-line samples from GSE62128 (Set1), and fluid flow-treated MLO-Y4 samples from GSE42874 (Set2) were employed. After identifying the differentially expressed genes (DEGs), functional enrichment was performed. The common DEGs between Set1 and Set2 were considered as key DEGs, then a protein-protein interaction (PPI) network was constructed using the minimal nodes from all of the DEGs in Set1 and Set2, which linked most of the key DEGs. Several open source software programs were employed to process and analyze the original data. The bioinformatic results and the biological meaning were validated by in vitro experiments. High gravity and fluid flow induced opposite expression trends in the key DEGs. The hypoxia-related biological process and signaling pathway were the common functional enrichment terms among the DEGs from Set1, Set2 and the PPI network. The expression of almost all the key DEGs (Pdk1, Ccng2, Eno2, Egln1, Higd1a, Slc5a3 and Mxi1) were mechano-sensitive. Eno2 was identified as the hub gene in the PPI network. Eno2 knockdown results in expression changes of some other key DEGs (Pdk1, Mxi1 and Higd1a). Our findings indicated that the hypoxia response might have an important role in the differential responses of osteocytes to the different types of mechanical force.


Assuntos
Biologia Computacional/métodos , Estudos de Associação Genética , Osteócitos/metabolismo , Transdução de Sinais/genética , Estresse Mecânico , Animais , Linhagem Celular , Perfilação da Expressão Gênica , Mecanotransdução Celular/genética , Camundongos , Mapas de Interação de Proteínas/genética
10.
Angle Orthod ; 89(2): 333-349, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30080111

RESUMO

This report illustrates successful nonsurgical orthodontic treatment of a hypodivergent adult patient with bilateral posterior scissors bite (Brodie bite) and excessive overjet. A 26-year-old woman primarily reported maxillary incisor protrusion. She was diagnosed with Class ll division 1 malocclusion with skeletal Class I, short face, low mandibular plane angle and bilateral posterior scissors bite. A lingual arch with anterior bite block and posterior miniscrews with preadjusted edgewise appliances were used to improve the bilateral scissors bite. After achieving molar occlusion, the maxillary first premolars were extracted, and six miniscrews were used to improve the anterior-posterior and vertical discrepancies. After active treatment for 56 months, the convex facial profile with excessively protruded lips was improved and good interdigitation with ideal incisor relationship was achieved. Additionally, the irregular movements of the incisal path and the bilateral condyles during lateral excursion were improved. At 13 months of retention, a satisfactory facial profile, occlusion, and jaw movements were maintained. The treatment results suggest that miniscrews and fixed bite blocks were effective and efficient to facilitate correction of the bilateral scissors bite, excessive overjet, and vertical relationship correction in this nonsurgical orthodontic treatment.


Assuntos
Má Oclusão de Angle Classe III , Má Oclusão de Angle Classe II , Mordida Aberta , Procedimentos de Ancoragem Ortodôntica , Sobremordida , Técnicas de Movimentação Dentária , Adulto , Cefalometria , Oclusão Dentária , Feminino , Humanos , Sobremordida/terapia
11.
Am J Orthod Dentofacial Orthop ; 154(5): 718-732, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30384943

RESUMO

Prader-Willi syndrome (PWS) is a complex disorder that affects multiple systems and may cause craniofacial and dentofacial abnormalities. However, there is still a lack of evidence in the literature regarding the progress of orthodontic treatment in patients with PWS. This case report describes the successful orthodontic treatment of a patient with PWS. A girl, 9 years 0 months of age, who had been diagnosed with PWS had protruding maxillary incisors and a convex profile. Her malocclusion was due to the posteriorly positioned mandible. Screening tests for sleep apnea syndrome showed that she had sleep-disordered breathing, including obstructive sleep apnea and bruxism. We also observed an excessive overjet of 10.0 mm, a deep overbite of 6.8 mm, and the congenital absence of the mandibular second premolars. The patient was diagnosed with an Angle Class II malocclusion and a skeletal Class II jaw-base relationship with a deep overbite. Functional appliance therapy with mandibular advancement, which can enlarge the upper airway and increase the upper airspace, was performed to prevent further deterioration of the patient's obstructive sleep apnea. An acceptable occlusion with a proper facial profile and functional excursion were achieved without interference after comprehensive 2-stage treatment that incorporated orthodontic therapy for the patient's excessive overjet and deep overbite. The resulting occlusion was stable, and the occlusal force and the contact area gradually increased over a 2-year retention period. These results suggest that orthodontic treatment offers the opportunity to greatly improve the health and quality of life of people with PWS.


Assuntos
Aparelhos Ortodônticos Funcionais , Sobremordida/etiologia , Sobremordida/terapia , Síndrome de Prader-Willi/complicações , Anodontia/complicações , Dente Pré-Molar , Criança , Feminino , Humanos , Avanço Mandibular , Sobremordida/diagnóstico , Qualidade de Vida , Apneia Obstrutiva do Sono/etiologia , Bruxismo do Sono/etiologia , Resultado do Tratamento
12.
Biochem Biophys Res Commun ; 503(3): 1798-1804, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30060947

RESUMO

The use of human induced pluripotent stem (iPS) cells has been investigated in multiple regenerative medicine studies. However, although methods for efficient differentiation of iPS cells into heart tissues have been devised, it remains difficult to obtain cardiac tissue with high contractility. Herein, we established a method for differentiating iPS cells into highly contractile cardiomyocytes (CMs), and demonstrate that the use of human gingival fibroblasts (HGFs) as a feeder cells promotes maturation of iPS-derived CMs (iPS-CMs) in vitro. After CM differentiation of iPS cells, iPS-CMs showed increased mRNA expression of the CM specific maker cardiac troponin T (cTnT) in the absence and presence (on-feeder condition) of cocultured HGFs, and decreased expression of pluripotent markers was observed under both conditions. Protein expression of cTnT was also observed in immunocytochemical analyses, although on-feeder CMs showed comparatively robust sarcomere structure and significantly stronger contractility than feederless cardiomyocytes, suggesting that HGF feeder cells facilitate CM differentiation of iPS cells.


Assuntos
Diferenciação Celular , Células Alimentadoras/citologia , Fibroblastos/citologia , Gengiva/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Miócitos Cardíacos/citologia , Humanos
13.
J Cell Physiol ; 233(6): 4825-4840, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29150954

RESUMO

A vast number of long-noncoding RNAs (lncRNA) are found expressed in human cells, which RNAs have been developed along with human evolution. However, the physiological functions of these lncRNAs remain mostly unknown. In the present study, we for the first time uncovered the fact that one of such lncRNAs plays a significant role in the differentiation of chondrocytes and, possibly, of osteoblasts differentiated from mesenchymal stem cells, which cells eventually construct the human skeleton. The urothelial cancer-associated 1 (UCA1) lncRNA is known to be associated with several human malignancies. Firstly, we confirmed that UCA1 was expressed in normal human chondrocytes, as well as in a human chondrocytic cell line; whereas it was not detected in human bone marrow mesenchymal stem cells (hBMSCs). Of note, although UCA1 expression was undetectable in hBMSCs, it was markedly induced along with the differentiation toward chondrocytes, suggesting its critical role in chondrogenesis. Consistent with this finding, silencing of the UCA1 gene significantly repressed the expression of chondrogenic genes in human chondrocytic cells. UCA1 gene silencing and hyper-expression also had a significant impact on the osteoblastic phenotype in a human cell line. Finally, forced expression of UCA1 in a murine chondrocyte precursor, which did not possess a UCA1 gene, overdrove its differentiation into chondrocytes. These results indicate a physiological and important role of this lncRNA in the skeletal development of humans, who require more sustained endochondral ossification and osteogenesis than do smaller vertebrates.


Assuntos
Condrócitos/metabolismo , Condrogênese , Osteoblastos/metabolismo , Osteogênese , RNA Longo não Codificante/metabolismo , Células-Tronco/metabolismo , Animais , Desdiferenciação Celular , Linhagem Celular Tumoral , Senescência Celular , Condrogênese/genética , Evolução Molecular , Regulação da Expressão Gênica no Desenvolvimento , Células HEK293 , Humanos , Osteogênese/genética , Fenótipo , Primatas , RNA Longo não Codificante/genética , Transdução de Sinais
14.
J Bone Miner Metab ; 36(5): 519-528, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29027020

RESUMO

Osteocytes form a three-dimensional (3D) cellular network within the mineralized bone matrix. The cellular network has important roles in mechanosensation and mechanotransduction related to bone homeostasis. We visualized the embedded osteocyte network in chick calvariae and observed the flow-induced Ca2+ signaling in osteocytes using 3D time-lapse imaging. In response to the flow, intracellular Ca2+ ([Ca2+]i) significantly increased in developmentally mature osteocytes in comparison with young osteocytes in the bone matrix. To investigate the differences in response between young and developmentally mature osteocytes in detail, we evaluated the expression of osteocyte-related genes using the osteocyte-like cell line MLO-Y4, which was 3D-cultured within type I collagen gels. We found that the c-Fos, Cx43, Panx3, Col1a1, and OCN mRNA levels significantly increased on day 15 in comparison with day 7. These findings indicate that developmentally mature osteocytes are more responsive to mechanical stress than young osteocytes and have important functions in bone formation and remodeling.


Assuntos
Cálcio/metabolismo , Osteócitos/metabolismo , Crânio/anatomia & histologia , Crânio/metabolismo , Imagem com Lapso de Tempo , Animais , Técnicas de Cultura de Células , Diferenciação Celular/genética , Linhagem Celular , Forma Celular , Embrião de Galinha , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Imageamento Tridimensional , Mecanotransdução Celular/fisiologia , Camundongos , Osteócitos/citologia , Estresse Mecânico
15.
Cranio ; 36(4): 228-233, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28436308

RESUMO

OBJECTIVES: This study investigated the different effects of intraoral vertical ramus osteotomy (IVRO) and sagittal split ramus osteotomy (SSRO) on mandibular border movement. METHODS: The participants included 22 patients receiving IVRO and 22 patients receiving SSRO who were treated at Okayama University Hospital. Their mandibular border movement was evaluated in three dimensions with 6° of freedom using an optical recording system. RESULTS: A strong correlation between condylar and lower incisor movement was observed during maximum jaw protrusion and laterotrusion. Significant improvements in condylar and lower incisor movement were detected after orthognathic surgery during maximum jaw protrusion and laterotrusion in the IVRO group and during maximum jaw protrusion in the SSRO group. DISCUSSION: IVRO likely achieves greater improvement in jaw movement than SSRO. Therefore, the application of IVRO could be considered in the treatment of patients with jaw deformities featuring temporomandibular joint problems.


Assuntos
Mandíbula/fisiologia , Avanço Mandibular/métodos , Osteotomia Mandibular , Osteotomia Sagital do Ramo Mandibular , Prognatismo/cirurgia , Adulto , Cefalometria , Feminino , Humanos , Arcada Osseodentária/anatomia & histologia , Arcada Osseodentária/fisiologia , Masculino , Mandíbula/anatomia & histologia , Mandíbula/cirurgia , Côndilo Mandibular/fisiologia , Movimento , Osteotomia , Prognatismo/fisiopatologia , Resultado do Tratamento , Adulto Jovem
16.
Integr Biol (Camb) ; 9(11): 868-875, 2017 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-29091092

RESUMO

The collagen network acts as a scaffold for calcification and its three-dimensional structure influences bone strength. It is therefore important to observe the collagen network in detail and three-dimensionally. In this study, we observed the collagen network of chick embryonic calvariae in membranous bone three-dimensionally using orthogonally arranged FIB-SEM. A 25 × 25 µm area of chick embryonic calvaria was observed at a high resolution (25 nm per pixel). The inside of the bone (i.e. the primary calcified tissue), the bone cells (i.e. the osteoblasts and the osteocytes), the organelles, and the collagen fibrils were observed in detail. These structures were observed three-dimensionally using the Amira software program. In addition, the collagen fibrils of the bone were automatically extracted using the XTracing extension software program, and three-dimensional morphometry was performed. Almost all of the collagen fibrils ran along the longitudinal axis of the trabecular bone. We found that the regularity of the collagen fibril orientation was less remarkable in the osteoblast layer, which contained numerous osteoblasts. The collagen fibril orientation started to show regularity toward the central bone layer, which contained few bone cells.


Assuntos
Osso e Ossos/metabolismo , Colágeno/química , Matriz Extracelular/metabolismo , Osteoblastos/metabolismo , Osteócitos/metabolismo , Animais , Calcificação Fisiológica , Embrião de Galinha , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Microscopia Eletrônica de Varredura , Software
17.
Acta Med Okayama ; 71(5): 437-443, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29042703

RESUMO

The rare developmental defect, Goldenhar syndrome is characterized by complex craniofacial and dentofacial anomalies. Here we describe the successful orthodontic treatment of a 5-year-old Japanese Goldenhar syndrome patient with mild facial asymmetry, right microtia, right-side hearing loss, and tongue-thrusting by a modification of dentofacial growth using a non-surgical orthopedic treatment approach. Improvement of the vertical discrepancies on the affected side and canted occlusal plane as well as mandibular deviation were achieved with a functional orthopaedic approach. Stable and acceptable occlusion were obtained over the 32-month post-retention period. A non-surgical orthodontic treatment approach offers satisfactory facial aesthetic outcomes in Goldenhar syndrome.


Assuntos
Síndrome de Goldenhar/patologia , Má Oclusão/terapia , Aparelhos Ortodônticos , Adolescente , Humanos , Masculino
18.
Sci Rep ; 7(1): 13969, 2017 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-29070874

RESUMO

Several recent prospective clinical trials have investigated the effect of supplementary vibration applied with fixed appliances in an attempt to accelerate tooth movement and shorten the duration of orthodontic treatment. Among them, some studies reported an increase in the rate of tooth movement, but others did not. This technique is still controversial, and the underlying cellular and molecular mechanisms remain unclear. In the present study, we developed a new vibration device for a tooth movement model in rats, and investigated the efficacy and safety of the device when used with fixed appliances. The most effective level of supplementary vibration to accelerate tooth movement stimulated by a continuous static force was 3 gf at 70 Hz for 3 minutes once a week. Furthermore, at this optimum-magnitude, high-frequency vibration could synergistically enhance osteoclastogenesis and osteoclast function via NF-κB activation, leading to alveolar bone resorption and finally, accelerated tooth movement, but only when a static force was continuously applied to the teeth. These findings contribute to a better understanding of the mechanism by which optimum-magnitude high-frequency vibration accelerates tooth movement, and may lead to novel approaches for the safe and effective treatment of malocclusion.


Assuntos
Aceleração , Osteoclastos/citologia , Eletricidade Estática , Estresse Mecânico , Técnicas de Movimentação Dentária/instrumentação , Técnicas de Movimentação Dentária/métodos , Vibração , Animais , Fenômenos Biomecânicos , Masculino , Osteogênese , Ligamento Periodontal/citologia , Ratos , Ratos Wistar
19.
Front Physiol ; 8: 567, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28855872

RESUMO

Craniofacial morphology varies among individuals, which is regulated by the interaction between genes and the environment. Soft-diet feeding is a widely-used experimental model for studying the association between the skeletal morphology and muscle-related loading on the bone. Traditionally, these studies have been based on linear and angular measurements provided on two-dimensional (2D) radiographs in the lateral view. However, 2D observation is based on simplification of the anatomical structures and cannot detect three-dimensional (3D) changes in detail. In this study, we newly developed a modified surface-based analysis with micro-3D computed tomography (CT) to examine and detect the 3D changes in the mandible associated with soft-diet feeding. Mice at 3 weeks of age were fed a powdered soft-diet (SD) or hard-diet (HD) of regular rodent pellets until 9 weeks of age. Micro-CT images were taken at age 9 weeks to reconstruct the anatomical architecture images. A computer-generated averaged mandible was superimposed to directly visualize the morphological phenotypes. Gross observation revealed the apparent changes at the posterior body of the mandible, the angular process and the condyle between HD and SD mice. Significant differences in the mapping indicated the regions of significant displacement in the SD mice over the averaged 3D image of the HD mice. This map revealed that vertical displacement was most evident in 3D changes. We also noted a combination of vertical, transverse and anteroposterior directions of displacement in the condylar growth, resulting in complicated shape changes in the whole condylar process in SD mice. In contrast, transverse displacement was more significant in the coronoid process. The map analysis further showed the significant outward displacement of the inner surface of the alveolar process, which consequently resulted in thinning of the alveolar process.

20.
Am J Orthod Dentofacial Orthop ; 151(6): 1116-1124, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28554457

RESUMO

INTRODUCTION: Our objective was to elucidate the differences in treatment outcomes caused by the different mechanics of temporary anchorage devices (TADs) and Class III elastics in patients with Class III malocclusions. METHODS: Records of 23 patients with Angle Class III malocclusion were selected retrospectively. All had been treated with nonextraction comprehensive orthodontic treatment; 11 were treated with TADs and 12 with Class III elastics. Pretreatment and posttreatment lateral cephalograms were used for evaluation of the treatment outcomes. A paired t test and a Student t test were used for statistical analysis. RESULTS: In both groups, proper overjet and Class I molar relationships were achieved, and the occlusal plane was rotated counterclockwise. In the elastics group, distal tipping of the mandibular molars, extrusion of the mandibular incisors and maxillary molars, clockwise rotation of the mandibular plane angle, and increased ANB angle were observed. In the TADs group, distal tipping and intrusion of the mandibular molars, bodily movement of the mandibular incisors, and reduced mandibular plane angle were observed. CONCLUSIONS: In nonextraction treatment for Class III malocclusions, the mandibular plane angle was increased in the elastics group, whereas it was decreased in TADs group. Thus, we suggest that Class III elastics are preferred for low-angle, short-face patients, whereas TADs are preferred for high-angle, long-face patients.


Assuntos
Má Oclusão de Angle Classe III/terapia , Procedimentos de Ancoragem Ortodôntica/instrumentação , Aparelhos Ortodônticos Removíveis , Adolescente , Adulto , Cefalometria , Elastômeros , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Aparelho Ortodôntico , Estudos Retrospectivos , Resultado do Tratamento
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