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1.
J Orthod ; 50(4): 335-343, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36786416

RESUMO

AIM: This in vitro study investigates the limit of expansion forces and torque wrench forces developed by five skeletal bone expander designs (MICRO 2/4 expanders™) for clinical application. MATERIAL AND METHODS: A total of 30 skeletal expanders were placed in artificial bone blocks and mechanically tested, simulating maxillary expansion. Differences in jackscrew (Dentaurum™ [D], Superscrew™ [S] and Powerscrew™ [P]), number of orthodontic mini-implants (OMIs; two or four) and their placement inclinations (parallel 0° or 10° inclination) form five designs (D4/10°, S4/0°, S4/10°, P4/10° and P2/10°). Expansion forces and torque wrench values were registered, and radiographs were made initially and after 4 mm of expansion. Stress-strain curves were obtained after successive activations and the statistical analysis was performed as appropriate. RESULTS: Plastic deformations in the OMIs and jackscrew occurred around the activation numbers 11-13, with torque wrench values in the range of 500-700 cN. The maximum expansion forces in expanders with four OMIs varied from 93.0 (D4/10°) to 166.6 N (P4/10°) whereas two OMI expanders (P2/10°) registered forces of 79.4 N. Radiographs revealed during loads bending forces (S4/00°, S4/10°) with jackscrew and OMIs deformation in a convex shape, and shear forces (P4/10°, P2/10°) demonstrated only OMIs deformation in a concave shape, providing 15% more expansive force. The jackscrew D4/10° did not have any deformation, but its wire key did not allow reliable activations from activation number 10 and compared to S4/10° and P4/10°, these expanders provided greater expansion forces (P = 0.000 and P = 0.032, respectively). CONCLUSION: The different results obtained in stability and expansion forces indicate that if the activations are carried out under extreme conditions, they may have clinical importance with deformations and non-working expansion mechanics. Jackscrew designs play an important role in expansive forces and expander stability. Torque wrench values can be used clinically as a tool to asses the expansion forces and to avoid deformations.


Assuntos
Implantes Dentários , Procedimentos de Ancoragem Ortodôntica , Humanos , Procedimentos de Ancoragem Ortodôntica/métodos , Maxila , Técnica de Expansão Palatina
2.
Arq Neuropsiquiatr ; 80(11): 1104-1111, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36577409

RESUMO

BACKGROUND: Some studies show an association between the apolipoprotein E ε4 allele (ApoEε4) and obstructive sleep apnea syndrome (OSAS), and other studies, an association between ApoEε4 and excessive daytime sleepiness (EDS), but there are no data in the literature on the interaction between EDS, cognitive function, and ApoEε4 in patients with OSA. OBJECTIVE: To examine the cognitive function of adults with and without EDS and with and without ApoEε4. METHODS: A total of 21 male and female patients aged between 33 and 79 years, underwent a clinical interview, ApoE genotyping, neuropsychological evaluation, polysomnography, and the application of the Epworth Sleepiness Scale. RESULTS: Excessive daytime sleepiness was associated with lower intelligence quotient (IQ; total performance) and worse immediate visual memory, regardless of the ApoE genotype. Patients carrying the ApoEε3/ε4 genotype had a worse performance in divided attention, constructional praxis, perceptual organization, and cognitive flexibility. A combination of the ε4 allele and EDS potentiates the negative effect on cognition, except for immediate visual memory. In this case, patients had a worse performance in terms of processing speed, selective attention, and visuomotor coordination. CONCLUSIONS: Excessive daytime sleepiness and the ApoEε3/ε4 genotype are associated with worse cognitive performance in OSA patients. The combination of EDS and ε4 allele potentiates cognitive impairment.


ANTECEDENTES: Alguns estudos mostram uma associação entre o alelo ε4 da apolipoproteina E (ApoEε4) e a síndrome da apneia obstrutiva do sono (SAOS), e outros, entre ApoEε4 e a sonolência excessiva diurna (SED), mas não há dados na literatura sobre a interação entre SED, função cognitiva e ApoEε4 em pacientes com SAOS. OBJETIVO: Avaliar a função cognitiva em adultos com SAOS com e sem SED e com e sem ApoEε4. MéTODOS: Ao todo, 21 pacientes, de 33 a 79 anos, homens e mulheres, foram avaliados clinicamente, e submetidos a genotipagem ApoE, avaliação neuropsicológica, polissonografia, e aplicação da Escala de Sonolência de Epworth. RESULTADOS: A SED esteve associada com menor quociente de inteligência (QI; desempenho geral) e pior memória visual imediata, independentemente do genótipo ApoE. Pacientes com genótipo ApoEε3/ε4 apresentaram pior desempenho na atenção dividida, praxe construcional, organização perceptiva e flexibilidade cognitiva. A combinação do alelo ε4 com a SED potencializa esse efeito deletério na cognição, exceto na memória visual imediata. Nesse caso, os pacientes tiveram uma menor velocidade de processamento cognitivo, e piores atenção seletiva e coordenação visiomotora. CONCLUSõES: A SED e o genótipo ApoEε3/ε4 estão associados a um pior desempenho cognitivo em pacientes com SAOS. A combinação de SED e do alelo ε4 potencializa esse efeito.


Assuntos
Apolipoproteínas E , Cognição , Distúrbios do Sono por Sonolência Excessiva , Apneia Obstrutiva do Sono , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Apolipoproteínas E/genética , Distúrbios do Sono por Sonolência Excessiva/genética , Distúrbios do Sono por Sonolência Excessiva/complicações , Genótipo , Apneia Obstrutiva do Sono/complicações
3.
Arq. neuropsiquiatr ; 80(11): 1104-1111, Nov. 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1429858

RESUMO

Abstract Background Some studies show an association between the apolipoprotein E ε4 allele (ApoEε4) and obstructive sleep apnea syndrome (OSAS), and other studies, an association between ApoEε4 and excessive daytime sleepiness (EDS), but there are no data in the literature on the interaction between EDS, cognitive function, and ApoEε4 in patients with OSA. Objective To examine the cognitive function of adults with and without EDS and with and without ApoEε4. Methods A total of 21 male and female patients aged between 33 and 79 years, underwent a clinical interview, ApoE genotyping, neuropsychological evaluation, polysomnography, and the application of the Epworth Sleepiness Scale. Results Excessive daytime sleepiness was associated with lower intelligence quotient (IQ; total performance) and worse immediate visual memory, regardless of the ApoE genotype. Patients carrying the ApoEε3/ε4 genotype had a worse performance in divided attention, constructional praxis, perceptual organization, and cognitive flexibility. A combination of the ε4 allele and EDS potentiates the negative effect on cognition, except for immediate visual memory. In this case, patients had a worse performance in terms of processing speed, selective attention, and visuomotor coordination. Conclusions Excessive daytime sleepiness and the ApoEε3/ε4 genotype are associated with worse cognitive performance in OSA patients. The combination of EDS and ε4 allele potentiates cognitive impairment.


Resumo Antecedentes Alguns estudos mostram uma associação entre o alelo ε4 da apolipoproteina E (ApoEε4) e a síndrome da apneia obstrutiva do sono (SAOS), e outros, entre ApoEε4 e a sonolência excessiva diurna (SED), mas não há dados na literatura sobre a interação entre SED, função cognitiva e ApoEε4 em pacientes com SAOS. Objetivo Avaliar a função cognitiva em adultos com SAOS com e sem SED e com e sem ApoEε4. Métodos Ao todo, 21 pacientes, de 33 a 79 anos, homens e mulheres, foram avaliados clinicamente, e submetidos a genotipagem ApoE, avaliação neuropsicológica, polissonografia, e aplicação da Escala de Sonolência de Epworth. Resultados A SED esteve associada com menor quociente de inteligência (QI; desempenho geral) e pior memória visual imediata, independentemente do genótipo ApoE. Pacientes com genótipo ApoEε3/ε4 apresentaram pior desempenho na atenção dividida, praxe construcional, organização perceptiva e flexibilidade cognitiva. A combinação do alelo ε4 com a SED potencializa esse efeito deletério na cognição, exceto na memória visual imediata. Nesse caso, os pacientes tiveram uma menor velocidade de processamento cognitivo, e piores atenção seletiva e coordenação visiomotora. Conclusões A SED e o genótipo ApoEε3/ε4 estão associados a um pior desempenho cognitivo em pacientes com SAOS. A combinação de SED e do alelo ε4 potencializa esse efeito.

4.
Int Orthod ; 20(1): 100604, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35039240

RESUMO

When using clear aligners, if distalization greater than 3mm is required, there is no real predictable procedure to follow. The aim of this article is to show with two clinical cases the biomechanics of distalizing lower molars with mini-implant anchorage and aligners.


Assuntos
Má Oclusão Classe II de Angle , Procedimentos de Ancoragem Ortodôntica , Aparelhos Ortodônticos Removíveis , Cefalometria/métodos , Humanos , Má Oclusão Classe II de Angle/diagnóstico por imagem , Má Oclusão Classe II de Angle/terapia , Maxila , Dente Molar , Procedimentos de Ancoragem Ortodôntica/métodos , Desenho de Aparelho Ortodôntico , Técnicas de Movimentação Dentária/métodos
5.
J Evol Biol ; 35(3): 391-399, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34953159

RESUMO

Cooperation involving shared resource systems is prone to 'the tragedy of the commons', where individuals act in their own self-interest to exploit the resource in a manner that is detrimental to the common good of all group members. Directing cooperation towards kin provides a solution to this problem and predicts the differential performance depending on the relatedness of group members. In subsocial spiders, juveniles live in transient groups that cooperate in hunting and communal feeding. Prey capture is costly in terms of risk of injury and investment of venom and digestive enzymes, and therefore presents a situation where individuals may attempt to avoid costly interactions and exploit the resource acquired by other group members. We tested the prediction that individuals differentiate participation and/or investment in cooperative prey capture and extra-oral digestion (injection of digestive enzymes into prey prior to the initiation of extraction of nutrients) in response to the relatedness of group members with whom they interact, in the subsocial spider Stegodyphus africanus. The performance of groups and interactions over prey attack in groups of either related or mixed kin spiderlings were determined over a period of 4 weeks. We show that kin groups attack the prey significantly faster, recruit individuals to form feeding groups faster, extract prey body mass more efficiently and experience less antagonistic interactions than groups of mixed relatedness, which ultimately translates into an elevated growth rate. These results indicate that related individuals are more willing to take risks and invest in communal digestion when foraging with kin, as predicted by inclusive fitness theory as a solution to the tragedy of the commons.


Assuntos
Aranhas , Animais , Aranhas/fisiologia
6.
Head Face Med ; 17(1): 50, 2021 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-34895287

RESUMO

INTRODUCTION: Bone-borne miniscrew assisted palatal expansion (MAPE) is a common technique to improve maxillary transverse deficiency in young adolescents. Adult patients usually present a challenge, as they often require additional surgical assisted maxillary expansion (SARPE). There is still no clear statement about non-surgical expansion in adult patients using this technique. The aim of this study was to evaluate the success and complication rate of non-surgical palatal expansion in adults utilizing MAPE with a novel force-controlled polycyclic expansion protocol (FCPC). METHODS: This consecutive study consisted of 33 adult patients with an average age of 29.1 ± 10.2 years (min. 18 years, max. 58 years), including one dropout patient. First, four miniscrews were inserted and after 12-weeks latency, the expander was placed and the FCPC protocol was applied (MAPE group). In case of missing expansion, a SARPE was performed (SARPE group). After maximum expansion, a cone beam CT was made and widening of the midpalatal suture was measured. The outcome variables were successful non-surgical expansion and, with sample size power above 80%, the odds of failed non-surgical expansion and associated complications were evaluated. The primary predictor variable was age. Statistical analysis was performed using R (Version 3.1) to calculate power, to construct various models for measuring the odds of requiring surgical intervention/complications, and others. RESULTS: Successful non-surgical expansion was achieved in 27 patients (84.4%), ranging from 18 to 49 years. Mean age differed significantly between both groups (26.8 ± 8.2 years vs. 41.3 ± 9.9 years; p < 0.001). Mean expansion at the anterior and posterior palate for the MAPE group was 5.4 ± 1.5 mm and 2.5 ± 1.1 mm, respectively. Among these subjects' complications were observed in 18.5%. Age significantly increased the odds of complications (p = 0.019). CONCLUSIONS: 1. The success rate of MAPE among individuals aged 18 to 49 years was 84.4%. 2. A V-shaped expansion pattern in the antero-posterior dimension was mostly observed. 3. Complications were significantly associated with age. 4. A careful expansion protocol seems to be beneficial to prevent unfavorable results in adult patients. TRIAL REGISTRATION: Consecutive cohort study, Review Board No. EK-2-2014/0016.


Assuntos
Técnica de Expansão Palatina , Palato , Adolescente , Adulto , Estudos de Coortes , Tomografia Computadorizada de Feixe Cônico , Humanos , Maxila , Palato/cirurgia , Adulto Jovem
7.
Int Orthod ; 17(2): 384-394, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31029533

RESUMO

Facial asymmetry is a common complaint in patients with facial concerns. Some patients have mandibular asymmetries that have light maxillary cant compensation due to a reduced gingival exposure. A common treatment in facial asymmetries is bimaxillary surgery treatment. However, there are no cases of non-severe occlusal plane canting (OPC) with mandibular asymmetry treated with mandibular surgery and miniscrews for the extrusion of the maxillary molars. The aim of this article is to show how to correct mandibular asymmetries combined with OPC by making a single mandibular "early surgery" combined with the extrusion of the maxilla with miniscrews to correct the occlusal plane in order to avoid a Le Fort I surgery. This type of treatment provides lower medical costs, shorter surgeries, and less postoperative discomfort and invasion for patients.


Assuntos
Oclusão Dentária , Assimetria Facial/cirurgia , Má Oclusão/diagnóstico , Má Oclusão/cirurgia , Mandíbula/cirurgia , Procedimentos Cirúrgicos Ortognáticos/métodos , Parafusos Ósseos , Cefalometria , Feminino , Humanos , Masculino , Maxila , Pessoa de Meia-Idade , Dente Molar , Procedimentos de Ancoragem Ortodôntica/métodos , Aparelhos Ortodônticos Fixos , Radiografia Dentária , Técnicas de Movimentação Dentária , Resultado do Tratamento , Adulto Jovem
8.
Dental Press J Orthod ; 23(1): 37-45, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29791684

RESUMO

INTRODUCTION: The force applied to the teeth by fixed orthopaedic expanders has previously been studied, but not the force applied to the orthodontic mini-implant (OMI) used to expand the maxilla with Hyrax hybrid expanders (HHE). OBJECTIVE: The aim of this article was to evaluate the clinical safety of the components (OMI, abutment and double wire arms) of three different force-transmitting systems (FTS) for conducting orthopaedic maxillary expansion: Jeil Medical & Tiger Dental™, Microdent™ and Ortholox™. METHODS: For the realization of this in vitro study of the resistance to mechanical load, three different abutment types (bonded, screwed on, and coupling) and three different OMIs' diameters (Jeil™ 2.5 mm, Microdent™ 1.6 mm and Ortholox™ 2.2 mm) were used. Ten tests for each of these three FTS were carried out in a static lateral load in artificial bone blocks (Sawbones™) by a Galdabini universal testing machine, then comparing its performance. Comparisons of loads, deformations and fractures were carried out by means of radiographs of FTS components in each case. RESULTS: At 1- mm load and within the elastic deformation, FTS values ranged from 67 ± 13 N to 183 ± 48 N. Under great deformations, Jeil & Tiger™ was the one who withstood the greatest loads, with an average 378 ± 22 N; followed by Microdent™, with 201 ± 18 N, and Ortholox™, with 103 ± 10 N. At 3 mm load, the OMIs shaft bends and deforms when the diameter is smaller than 2.5 mm. The abutment fixation is crucial to transmit forces and moments. CONCLUSIONS: The present study shows the importance of a rigid design of the different components of HHEs, and also that HHEs would be suitable for maxillary expansion in adolescents and young adults, since its mean expansion forces exceed 120N. Furthermore, early abutment detachment or smaller mini-implants diameter would only be appropriate for children.


Assuntos
Desenho de Aparelho Ortodôntico , Aparelhos Ortodônticos Fixos , Técnica de Expansão Palatina/instrumentação , Adolescente , Humanos , Técnicas In Vitro , Teste de Materiais
9.
Dental press j. orthod. (Impr.) ; 23(1): 37-45, Jan.-Feb. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-891117

RESUMO

ABSTRACT Introduction: The force applied to the teeth by fixed orthopaedic expanders has previously been studied, but not the force applied to the orthodontic mini-implant (OMI) used to expand the maxilla with Hyrax hybrid expanders (HHE). Objective: The aim of this article was to evaluate the clinical safety of the components (OMI, abutment and double wire arms) of three different force-transmitting systems (FTS) for conducting orthopaedic maxillary expansion: Jeil Medical & Tiger Dental™, Microdent™ and Ortholox™. Methods: For the realization of this in vitro study of the resistance to mechanical load, three different abutment types (bonded, screwed on, and coupling) and three different OMIs' diameters (Jeil™ 2.5 mm, Microdent™ 1.6 mm and Ortholox™ 2.2 mm) were used. Ten tests for each of these three FTS were carried out in a static lateral load in artificial bone blocks (Sawbones™) by a Galdabini universal testing machine, then comparing its performance. Comparisons of loads, deformations and fractures were carried out by means of radiographs of FTS components in each case. Results: At 1- mm load and within the elastic deformation, FTS values ranged from 67 ± 13 N to 183 ± 48 N. Under great deformations, Jeil & Tiger™ was the one who withstood the greatest loads, with an average 378 ± 22 N; followed by Microdent™, with 201 ± 18 N, and Ortholox™, with 103 ± 10 N. At 3 mm load, the OMIs shaft bends and deforms when the diameter is smaller than 2.5 mm. The abutment fixation is crucial to transmit forces and moments. Conclusions: The present study shows the importance of a rigid design of the different components of HHEs, and also that HHEs would be suitable for maxillary expansion in adolescents and young adults, since its mean expansion forces exceed 120N. Furthermore, early abutment detachment or smaller mini-implants diameter would only be appropriate for children.


RESUMO Introdução: a força aplicada sobre os dentes por expansores ortopédicos fixos já foi estudada antes, mas não a força aplicada sobre os mini-implantes ortodônticos (MIOs) usados para expandir a maxila com expansores do tipo Hyrax híbrido (EHH). Objetivo: o objetivo desse artigo foi avaliar a segurança clínica dos componentes (MIO, abutment de fixação, e braços de fio duplo) de três sistemas de transmissão de força (STF) usados para expansão ortopédica da maxila: Jeil Medical & Tiger Dental™, Microdent ™ e Ortholox ™. Métodos: para realizar esse estudo in vitro sobre a resistência à carga mecânica, foram usadas três tipos de sistema de fixação (colado, aparafusado e coupling) e MIOs de três diâmetros diferentes (Jeil™ 2,5 mm; Microdent™ 1,6 mm e Ortholox™ 2,2 mm), com suas respectivas mecânicas de STF. Foram realizados 10 testes para cada STF, usando uma carga lateral estática em blocos de osso artificial (Sawbones™), com uma máquina universal de testes e, depois, comparou-se, por meio de radiografias, os desempenhos, levando-se em consideração as cargas, deformações e fraturas dos componentes de cada STF. Resultados: com a carga a 1 mm e sem exceder o limite de deformação elástica, os valores dos STFs variaram de 67 ± 13 N a 183 ± 48 N. Sob deformações maiores, o sistema Jeil & Tiger™ foi o que apresentou maior resistência às cargas elevadas, com valor de 378 ± 22 N; seguido pelo Microdent™, com 201 ± 18 N, e Ortholox™, com 103 ± 10 N. Com a carga a 3 mm, o eixo do MIO se dobrou e deformou quando seu diâmetro era menor que 2,5 mm. O abutment de fixação é crucial para a transmissão das forças e momentos. Conclusões: o presente estudo evidenciou a importância da rigidez no design dos diferentes componentes dos STFs dos EHH. Também revelou que eles são adequados para a expansão da maxila em adolescentes e adultos jovens, pois as forças de expansão, em média, excederam os 120N. Além disso, a desconexão precoce do abutment ou o uso de mini-implantes de menor diâmetro no design do STF seriam apropriados apenas em crianças.


Assuntos
Humanos , Adolescente , Técnica de Expansão Palatina/instrumentação , Desenho de Aparelho Ortodôntico , Aparelhos Ortodônticos Fixos , Técnicas In Vitro , Teste de Materiais
10.
BMC Genomics ; 18(1): 600, 2017 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-28797246

RESUMO

BACKGROUND: Spiders are predaceous arthropods that are capable of subduing and consuming relatively large prey items compared to their own body size. For this purpose, spiders have evolved potent venoms to immobilise prey and digestive fluids that break down nutrients inside the prey's body by means of extra-oral digestion (EOD). Both secretions contain an array of active proteins, and an overlap of some components has been anecdotally reported, but not quantified. We systematically investigated the extent of such protein overlap. As venom injection and EOD succeed each other, we further infer functional explanations, and, by comparing two spider species belonging to different clades, assess its adaptive significance for spider EOD in general. RESULTS: We describe the protein composition of the digestive fluids of the mygalomorph Acanthoscurria geniculata and the araneomorph Stegodyphus mimosarum, in comparison with previously published data on a third spider species. We found a number of similar hydrolases being highly abundant in all three species. Among them, members of the family of astacin-like metalloproteases were particularly abundant. While the importance of these proteases in spider venom and digestive fluid was previously noted, we now highlight their widespread use across different spider taxa. Finally, we found species specific differences in the protein overlap between venom and digestive fluid, with the difference being significantly greater in S. mimosarum compared to A. geniculata. CONCLUSIONS: The injection of venom precedes the injection with digestive fluid, and the overlap of proteins between venom and digestive fluid suggests an early involvement in EOD. Species specific differences in the overlap may reflect differences in ecology between our two study species. The protein composition of the digestive fluid of all the three species we compared is highly similar, suggesting that the cocktail of enzymes is highly conserved and adapted to spider EOD.


Assuntos
Líquidos Corporais/metabolismo , Digestão , Proteínas de Insetos/metabolismo , Proteômica , Aranhas/fisiologia , Sequência de Aminoácidos , Animais , Proteínas de Insetos/química , Aranhas/enzimologia , Aranhas/metabolismo
11.
J Craniomaxillofac Surg ; 45(4): 540-546, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28189490

RESUMO

Two techniques to separate the lower incisors prior to mandibular symphyseal distraction osteogenesis (MSDO) were evaluated with respect to avoiding tooth damage. METHODS: Fifty patients (20.2 ± 7.0 years) requiring MSDO were treated with a tooth-borne appliance by utilizing two preoperative protocols to separate the central incisors: i) brackets and a V-bent wire with an open coil spring (two-step; TS; n = 24) and ii) a wire attached from the appliance to the central incisors with subsequent dento-alveolar expansion prior to surgery (one-step; OS; n = 26). The distance between the lower incisors was measured preoperatively on radiographs and measurements at the cast models were performed. Complications and radiographs were analyzed. RESULTS: The mean distance (±SD) between the lower central incisors for OS and TS prior to surgery was 3.44 ± 1.05 and 3.18 ± 1.13 mm, respectively. The mean expansion for OS and TS was 4.3 ± 2.9 and 4.3 ± 2.7 mm at the dental level and 3.8 ± 3.2 and 4.0 ± 2.1 mm at the bone level, respectively. Four patients undergoing the TS and one patient undergoing the OS showed transient dental complications. CONCLUSION: Pre-surgical dento-alveolar expansion by utilizing a one-step technique to separate the lower central incisors reduces the risk of permanent tooth damage and weakens the mandibular bone in the midline.


Assuntos
Protocolos Clínicos , Incisivo/cirurgia , Complicações Intraoperatórias/prevenção & controle , Mandíbula/cirurgia , Osteogênese por Distração/métodos , Cuidados Pré-Operatórios/métodos , Traumatismos Dentários/prevenção & controle , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Fatores de Risco , Adulto Jovem
12.
Eur J Orthod ; 39(1): 76-84, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27036133

RESUMO

BACKGROUND: The aim was to test which component [wire arm, connecting abutment attachment, and orthodontic mini-implant (OMI)] of the force-transmitting system (FTS) in the anterior palate of three commonly used hybrid expanders (HEs; WILMES-HE, LUDWIG-HE, and WINSAUER-HE) deforms under increasing load. MATERIALS AND METHODS: Crude single and double wire arms were tested individually. Non-opening of the maxillae halves was simulated in artificial bone blocks with single wire and double wire FTS specimens. OMIs were inserted 8mm and underwent 6mm of continuous static lateral loading. Deformation angles were measured (X-ray, n = 6) at 0, 3 and 6mm feed. OMIs and abutments were scan electron microscope (SEM) evaluated. RESULTS: After 1.0mm of loading, the single wire arm of all FTS deformed between 63.4 (16.5) N and 76.2 (18.4) N, and the double wire arm of reinforced FTS (wires positioned 'side by side') deformed after 1.0mm between 110.0 (18.4) N and 134.8 (22.3) N. The crude single wire resisted 89 (5.1) N until plastic deformation, whereas the crude double wire positioned 'on top of each other' resisted 438 (21.3) N. At 6mm loading, the reinforced WINSAUER-HE FTS withstood a maximum load of 320.9 (31.1) N and the reinforced LUDWIG-HE FTS 19% less, both under great deformation of double wires and OMIs. The screw-fixated WILMES-HE FTS abutment attachment (overlapping OMI head 34%) detached around 250N. The bonded WINSAUER-HE and LUDWIG-HE abutment attachments did not detach. Nor did the modified bonded plus the modified screw-fixated WILMES-HE abutment attachment when overlapping 100%. CONCLUSION: Early OMI and single wire arm deformation in HEs are crucial for unsuccessful RME in more mature maxillae. Double wire arms should be obligatory. OMIs with inner diameter greater 1.36mm are recommended. One hundred per cent overlapping abutment attachments do not detach.


Assuntos
Dente Suporte/normas , Análise do Estresse Dentário , Teste de Materiais/normas , Humanos , Fenômenos Mecânicos , Estresse Mecânico
14.
Naturwissenschaften ; 103(11-12): 93, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27787598

RESUMO

The quality of many animal signals varies, perhaps through their use in different contexts or by representing an adaptive response to reduce the risk of exploitation. Spiders of the orb weaver genus Argiope add linear, cruciate or circular silk structures to their orb webs, creating inter- and intra-specific polymorphic visual signals. Different decoration patterns are frequently attributed to different signal effects, but this view is contradicted by commonly observed intraspecific variation in decorating behaviour. Adults of Argiope mascordi are bimodal web decorators, building two distinct patterns, circular and cruciate silk structures. We investigated the variation of patterns under controlled, invariant laboratory conditions. Circular decorations were most frequent, but individuals often switch to the other pattern. This variation neither increased nor decreased over time, suggesting that pattern variability is primarily intrinsic rather than an exclusive response to environmental changes. Accordingly, we discuss the evolutionary implications in the light of the conservation of a single signal function through maintaining the variation of its quality and the alternative view that silk decorations may not represent adaptive signals at all.


Assuntos
Comunicação Animal , Comportamento Animal/fisiologia , Meio Ambiente , Aranhas/fisiologia , Animais
16.
Arq. neuropsiquiatr ; 73(3): 260-280, 03/2015. tab
Artigo em Inglês | LILACS | ID: lil-741193

RESUMO

The Consensus on restless legs syndrome is an effort of neurologists from several Brazilian states, which tirelessly reviewed the literature of recent years in search of evidence, both in regard to diagnosis and treatment, according to the Oxford Centre for Evidence-based Medicine.


O Consenso em síndrome das pernas inquietas contou com a participação de neurologistas de vários estados brasileiros, os quais incansavelmente revisaram a literatura dos últimos anos em busca de evidências, tanto no que se refere ao diagnóstico como ao tratamento, de acordo com a Classificação do Centro de Oxford para Medicina Baseada em Evidências.


Assuntos
Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Cálculos Renais/cirurgia , Nefrostomia Percutânea/métodos , Estudos de Viabilidade , Índia , Nefrostomia Percutânea/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
17.
Front Aging Neurosci ; 6: 134, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25009494

RESUMO

Some individuals are able to successfully reach very old ages, reflecting higher adaptation against age-associated effects. Sleep is one of the processes deeply affected by aging; however few studies evaluating sleep in long-lived individuals (aged over 85) have been reported to date. The aim of this study was to characterize the sleep patterns and biochemical profile of oldest old individuals (N = 10, age 85-105 years old) and compare them to young adults (N = 15, age 20-30 years old) and older adults (N = 13, age 60-70 years old). All subjects underwent full-night polysomnography, 1-week of actigraphic recording and peripheral blood collection. Sleep electroencephalogram spectral analysis was also performed. The oldest old individuals showed lower sleep efficiency and REM sleep when compared to the older adults, while stage N3 percentage and delta power were similar across the groups. Oldest old individuals maintained strictly regular sleep-wake schedules and also presented higher HDL-cholesterol and lower triglyceride levels than older adults. The present study revealed novel data regarding specific sleep patterns and maintenance of slow wave sleep in the oldest old group. Taken together with the favorable lipid profile, these results contribute with evidence to the importance of sleep and lipid metabolism regulation in the maintenance of longevity in humans.

18.
Med. oral patol. oral cir. bucal (Internet) ; 18(5): 804-810, sept. 2013. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-126455

RESUMO

OBJECTIVE: Orthodontic mini-implants (OMIs) are increasingly used in orthodontics but can fail for various reasons. This study investigates the effects of OMI design characteristics on the mechanical properties in artificial bone. MATERIAL AND METHODS: Twelve self-drilling OMIs (2 small, 6 medium, 4 large) from 8 manufacturers were tested for their primary stability in simulated medium-high cancellous bone and the risk to fracture in high-density methacrylate blocks. For the assessments of the maximum insertion torque (IT) and torsional fracture (TF) 5 of each OMI were used and for the pull-out strength (POS) 10. The OMIs were inserted with a torque screwdriver (12 sec/360°) until the bottom at 8 mm depth was reached. OMI designs were analyzed with a scan electron microscope (SEM).RESULTS:SEM images revealed a great variation in product refinement. In the whole sample, a cylindrical OMI shape was associated with higher POS (p<0.001) but lower IT (p=0.002) values. The outer and inner OMI diameters were design characteristics well correlated with POS, IT and TF values (ranging from 0.601 to 0.961). Greater thread depth was related to greater POS values (r= 0.628), although OMIs with similar POS values may have different IT values. Thread depth and pitch had some impact on POS. TF depended mainly on the OMI inner (r= 0.961) and outer diameters (r=0.892). A thread depth to outer diameter ratio close to 40% increased TF risk. CONCLUSION: Although at the same insertion depth the OMI outer and inner diameters are the most important factors for primary stability, other OMI design characteristics (cylindrical vs. conical, thread design) may significantly affect primary stability and torsional fracture. This needs to be considered when selecting the appropriate OMI for the desired orthodontic procedures (AU)


Assuntos
Humanos , Desenho de Aparelho Ortodôntico/métodos , Procedimentos de Ancoragem Ortodôntica/métodos , Implantação Dentária Endóssea/métodos , Retenção de Dentadura/métodos , Fraturas dos Dentes/prevenção & controle
19.
Int J Oral Maxillofac Implants ; 28(4): e177-89, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23869375

RESUMO

PURPOSE: Unlike standard dental implants, the stabilization of orthodontic microscrews removed after treatment is done without osseointegration and achieved by several components: cortical bone thickness (CBT), microscrew geometry, and drilling depth. The purpose of this study was to evaluate 10 different microscrews and the influence of their geometric parameters with different CBT and drilling depths. MATERIALS AND METHODS: The influence of geometric parameters in cortical bone was analyzed with a series of computational simulations with finite element models to obtain von Mises stresses and deformations in the microscrew when loaded with a perpendicular traction force of 1 N and considering the angle of incidence as a random parameter. RESULTS: There was variability in the angle of incidence, with less clinical influence. Biomechanical parameters such as microscrew diameter, CBT, and drilling depth had significant influences on the results. At a drilling distance of 8 mm, narrow microscrews (Abso Anchor 1.2) showed maximum von Mises stress of 500.698 MPa and maximum deformation in the shank of 0.08549 mm. Microscrews with a diameter of 1.5 mm (Dentaurum, Jeil, Mondeal, Tekka, Spider) showed von Mises stresses ranging from 56.97 to 136 MPa and deformation between 0.0062055 and 0.0476 mm. Microscrews with a diameter of 2.0 mm (Jeil, Mondeal, Tekka) showed von Mises stresses ranging from 17.172 to 54.861 MPa and deformation of 0.000172 to 0.0161 mm. CONCLUSIONS: The shape and geometry of an orthodontic microscrew are highly important in its behavior. Optimal characteristics of a microscrew would include a diameter of 2.0 mm, a cylindric shape, a short and wide head, a short and wide shank, and threads of an appropriate size.


Assuntos
Parafusos Ósseos , Implantes Dentários , Análise do Estresse Dentário , Arcada Osseodentária/fisiologia , Análise de Elementos Finitos , Humanos , Estresse Mecânico , Tração
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