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1.
Dent Traumatol ; 39(2): 132-139, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36428271

RESUMO

BACKGROUND/AIM: Dental trauma may occur in school settings and it can impact patients' quality of life. Analysis of the occurrences of dental trauma is essential in identifying preventive methods. There are numerous reports of such accidents but most are quantitative analyses with limited data. The aim of this study was to extract information on the mechanisms of injuries that leads to prevention by performing a qualitative analysis of the occurrence of dental trauma. MATERIAL AND METHODS: After screening 7684 cases of dental injuries that occured in schools and were reported to the Japan Sports Council between 2005 and 2020, 533 detailed descriptions of injuries that occurred during sports were included. Quantitative text analysis was performed on the target data by performing statistical analysis, extracting frequently used words, and creating a co-occurrence network. Injury mechanisms were evaluated based on appearance of words. RESULTS: Dental injuries occurred frequently in five sports included in the survey. They were in order of decreasing frequency: baseball, basketball, soccer, volleyball, and rugby. Males were injured more often in all sports other than volleyball. The number of accidents increased in all sports among high school students. The frequent word list and co-occurrence network were different for each sport. This allowed typical accident occurrence mechanisms to be extracted for these five sports. CONCLUSIONS: Typical accident occurrence mechanisms were extracted from quantitative text analysis targeting free texts on the occurrence of accidents for five sports. Quantitative text analysis is useful for the evaluation of accident cases, which may aid in accident prevention.


Assuntos
Traumatismos em Atletas , Basquetebol , Traumatismos Dentários , Masculino , Humanos , Qualidade de Vida , Traumatismos em Atletas/epidemiologia , Basquetebol/lesões , Traumatismos Dentários/epidemiologia , Acidentes
2.
Sensors (Basel) ; 21(4)2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33671506

RESUMO

Teeth clenching during exercise is important for sports performance and health. Recently, several mouth guard (MG)-type wearable devices for exercise were studied because they do not disrupt the exercise. In this study, we developed a wearable MG device with force sensors on both sides of the maxillary first molars to monitor teeth clenching. The force sensor output increased linearly up to 70 N. In four simple occlusion tests, the trends exhibited by the outputs of the MG sensor were consistent with those of an electromyogram (EMG), and the MG device featured sufficient temporal resolution to measure the timing of teeth clenching. When the jaw moved, the MG sensor outputs depended on the sensor position. The MG sensor output from the teeth-grinding test agreed with the video-motion analysis results. It was comparatively difficult to use the EMG because it contained a significant noise level. Finally, the usefulness of the MG sensor was confirmed through an exercise tolerance test. This study indicated that the developed wearable MG device is useful for monitoring clenching timing and duration, and the degree of clenching during exercise, which can contribute to explaining the relationship between teeth clenching and sports performance.


Assuntos
Bruxismo , Protetores Bucais , Dispositivos Eletrônicos Vestíveis , Força de Mordida , Eletromiografia , Humanos , Contração Muscular
3.
Dent Traumatol ; 37(4): 617-622, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33620153

RESUMO

BACKGROUND/AIM: Sports mouthguards are effective devices that prevent dental trauma in sports activities. Players should change mouthguards on a regular basis because of thickness reduction and shape deformation. However, there is no guidance regarding the best timing to change mouthguards. The aims of this study were to analyze the thickness change and deformation of mouthguards after 2 years of use in Bangladesh field hockey players and to consider appropriate evaluation criteria. MATERIAL AND METHODS: Fifty-seven field hockey players belonging to the Bangladesh Sports Education Institute participated in this study. Participants were provided with double-layered mouthguards made of polyolefin-based material using a vacuum-forming machine. Mouthguards were fabricated using 2-mm-thick sheet as the first layer and 3-mm-thick sheet as the second layer. Players used the mouthguards for 2 years. Before and after using the mouthguards, the thicknesses of nine areas were measured. In addition, the lengths of five areas were used to analyze shape deformation. RESULTS: After 2 years, the thicknesses of all measured areas had significantly reduced, and the lengths had significantly increased. Thickness reduction of the posterior-occlusal and anterior-incisal areas and deformation of the posterior-buccal and posterior-palatal areas were significantly larger than those in other measured areas. CONCLUSIONS: Mouthguards should be changed on a regular basis to minimize thickness reduction and deformation. Occlusal and incisal thickness and length of the buccal-posterior area and the palatal-posterior area are factors to be considered in establishing guidelines regarding the timing of mouthguard change.


Assuntos
Hóquei , Protetores Bucais , Desenho de Equipamento , Humanos , Vácuo
4.
Eur J Dent Educ ; 25(4): 796-805, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33387390

RESUMO

INTRODUCTION: Insufficient educational resources on sports dentistry result in varying lecture implementations across dental schools, which cause knowledge gaps amongst students. Thus, a new interactive sports dentistry-related computer-assisted learning (CAL) module was created to facilitate dental school undergraduate students' education. This study compared the CAL module's learning effectiveness with conventional video lectures (VL) and assessed its effectiveness when used over several years at a university, and examined its validation in different university contexts, and students' perceptions. MATERIALS AND METHODS: Participants were 305 fifth-year students. Students from a university in Tokyo participated for 3 years and those from a university in Saitama for 1 year. In each year, the students were divided into two groups-CAL and VL. They studied their assigned modules in 20-min lessons. A written test was administered to determine their knowledge acquisition levels, along with a questionnaire. RESULTS: Two hundred sixty-two consenting participants were included in the statistical analysis. The CAL groups' test scores at both schools were significantly higher than the VL groups' every year (p < .001). Furthermore, test results from all years revealed no gender differences or repetition of the school years at either school. Most students at both universities evaluated the CAL module as excellent. CONCLUSION: The interactive CAL module generated consistently strong results over multiple years, during which it was used by a diverse group of students at two universities. The students highly rated the module's learning process as well as its contents.


Assuntos
Instrução por Computador , Universidades , Computadores , Odontologia , Educação em Odontologia , Avaliação Educacional , Humanos , Aprendizagem
5.
J Appl Biomech ; 33(3): 211-215, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27992243

RESUMO

The aim of this study was to analyze the effect of teeth clenching on dynamic balance at jump landing. Twenty-five healthy subjects performed jump-landing tasks with or without teeth clenching. The first 3 trials were performed with no instruction; subsequently, subjects were ordered to clench at the time of landing in the following 3 trials. We collected the data of masseter muscle activity by electromyogram, the maximum vertical ground reaction force (vGRFmax) and center of pressure (CoP) parameters by force plate during jump-landing. According to the clenching status of control jump-landing, all participants were categorized into a spontaneous clenching group and no clenching group, and the CoP data were compared. The masseter muscle activity was correlated with vGRFmax during anterior jump-landing, while it was not correlated with CoP. In comparisons between the spontaneous clenching and the no clenching group during anterior jump-landing, the spontaneous clenching group showed harder landing and the CoP area became larger than the no clenching group. There were no significant differences between pre- and postintervention in both spontaneous clenching and no clenching groups. The effect of teeth clenching on dynamic balance during jump-landing was limited.


Assuntos
Bruxismo , Músculo Esquelético/fisiologia , Exercício Pliométrico , Equilíbrio Postural , Adulto , Fenômenos Biomecânicos , Eletromiografia , Feminino , Humanos , Masculino , Projetos Piloto , Adulto Jovem
6.
Dent Traumatol ; 32(6): 474-479, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27126657

RESUMO

PURPOSE: The purpose of this study was to investigate the shock absorption capability of commercial thermoforming mouthguard sheet materials. MATERIALS AND METHODS: Twelve commercial thermoforming mouthguard sheet materials were selected as test materials. The impact test was applied by a free-falling steel ball. When impact forces of approximately 660 N were applied on the commercial thermoforming mouthguard materials, the peak intensities were measured using the load cell sensor. The peak intensity and the time to peak intensity from the onset of the transmitted force were statistically analyzed using one-way anova and Tukey's honest significant difference post hoc test (P < 0.05). RESULTS: Statistical analysis for the peak intensity and the time to peak intensity from the onset of the transmitted force revealed significant differences among the thirteen groups including the control. The peak intensity of the polystyrene-polyolefin copolymer-based material was lower than the peak intensity of the EVA-, polyolefin-based material. Polyolefin-based materials had a tendency of a long duration to reach peak intensity from the onset of the transmitted force. CONCLUSION: These results suggest that all of the commercially available mouthguard sheet materials had high shock-absorbing capabilities.


Assuntos
Desenho de Equipamento , Protetores Bucais , Teste de Materiais , Polivinil , Aço
7.
Undersea Hyperb Med ; 43(2): 135-42, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27265990

RESUMO

We examined the effect of hyperbaric oxygen (HBO2) treatment on bone wound healing in a rat calvarial defect. Critical-sized defects were created in the calvaria of adult Wistar rats. The animals were divided into four groups--HBO2, normobaric oxygen, hyperbaric air, and no treatment. Treatments were performed five days a week, for two weeks. Micro-computerized tomography and histological analysis were used to evaluate the bone defects. Regenerated bone areas were calculated as the percentage of new bone in the cross-sectional area of defect. The new bone cross-sectional area was significantly greater in the HBO2 group than in the other groups. There were no significant differences in the numbers of nucleated cells in the new bone areas. Although new bone volume per defect volume was significantly greater in the HBO2 group than in the other groups, no significant differences in bone mineral density in the new bone area were observed. These findings indicate the facilitatory role of HBO2 treatment on bone wound healing in the rat calvarial bone defect, and it does not appear to have any negative effects on bone maturity. We propose that HBO2 treatment would be useful in promoting bone regeneration following injury in the orofacial region.


Assuntos
Regeneração Óssea , Oxigenoterapia Hiperbárica , Crânio/lesões , Cicatrização , Animais , Densidade Óssea , Ratos , Ratos Wistar , Crânio/diagnóstico por imagem , Microtomografia por Raio-X
8.
Dent Traumatol ; 31(3): 238-42, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25283822

RESUMO

AIM: Custom-made mouthguard (MG) is popularly used by sports-active persons or athletes having either normo-occlussion or malocclusion to prevent dental injury. For sports-active person with malocclusion, specially designed mouthguard is often required. The purpose of this study was to make a suitable design custom-made mouthguard for sports-active person with spaced dentition by the shock absorption capability. MATERIALS AND METHODS: Two different types of double layered mouthguards were made from a model of a sports-active person having spaced dentition with polyolefin sheets. One type was made by filling the interproximal spaces of the spaced dentition and the other type, which was devoid of interproximal space covering, without mouthguard materials (keeping space). The impact tests were carried out by a free-falling object via testing machine and a vertical rod. The strains of the dentition with mouthguard were measured by means of strain gage system to compare between two different designs of mouthguard. Unpaired t-test was carried out as statistical analysis. RESULT: The strains of the dentition with mouthguard by filling the interproximal spaces were significantly low compared with the mouthguard by keeping spaces (P < 0.05). CONCLUSION: For sports-active person with spaced dentition, it is important for reducing injury risks that the mouthguard covered the teeth and filled or embedded interproximal space certainly.


Assuntos
Traumatismos em Atletas/prevenção & controle , Desenho de Equipamento , Má Oclusão/complicações , Protetores Bucais , Equipamentos Esportivos , Traumatismos Dentários/prevenção & controle , Humanos , Teste de Materiais , Polienos , Vácuo
9.
Dent Traumatol ; 30(3): 193-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24102720

RESUMO

PURPOSE: Several methods have been used to measure the impact force absorption capacities of mouthguard materials; however, the relationships among these measurement systems have not been clearly determined. The purpose of the present study was to evaluate the impact force-absorbing capability of materials using a drop-ball system with film sensors and load cells to clarify the relationship between these two sensor systems. MATERIALS AND METHODS: Disk-shaped specimens (1, 2, and 3 mm thick) were prepared using three commercial thermoplastic mouthguard materials (Bioplast, Impact Guard, MG 21) and one experimental mouthguard material [mixture of Poly (ethyl methacrylate)]. Impact force was applied by letting a stainless steel ball drop free-fall onto the specimens and then measuring the impact load under each specimen using a film sensor system and a load cell sensor system. RESULTS: The total load measured with the film sensor system decreased with an increase in mouthguard thickness, while almost none of the transmitted impact forces measured with the load cell system were statistically different. CONCLUSIONS: The film sensor system was considered to be superior to the load cell system because the maximum stress and stress area could be determined.


Assuntos
Teste de Materiais , Protetores Bucais
10.
Dent Traumatol ; 29(1): 23-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22458360

RESUMO

AIM: Experimental materials incorporating fiberglass cloth were used to develop a thin and lightweight face guard (FG). This study aims to evaluate the effect of fiberglass reinforcement on the flexural and shock absorption properties compared with conventional thermoplastic materials. MATERIAL AND METHOD: Four commercial 3.2-mm and 1.6-mm medical splint materials (Aquaplast, Polyform, Co-polymer, and Erkodur) and two experimental materials were examined for use in FGs. The experimental materials were prepared by embedding two or four sheets of a plain woven fiberglass cloth on both surfaces of 1.5-mm Aquaplast. The flexural strength and flexural modulus were determined using a three-point bending test. The shock absorption properties were evaluated for a 5200-N impact load using the first peak intensity with a load cell system and the maximum stress with a film sensor system. RESULTS AND CONCLUSIONS: The flexural strength (74.6 MPa) and flexural modulus (6.3 GPa) of the experimental material with four sheets were significantly greater than those of the 3.2-mm commercial specimens, except for the flexural strength of one product. The first peak intensity (515 N) and maximum stress (2.2 MPa) of the experimental material with four sheets were significantly lower than those of the commercial 3.2-mm specimens, except for one product for each property. These results suggest that the thickness and weight of the FG can be reduced using the experimental fiber-reinforced material.


Assuntos
Face , Vidro/química , Dispositivos de Proteção da Cabeça , Plásticos/química , Carboximetilcelulose Sódica/química , Módulo de Elasticidade , Desenho de Equipamento , Humanos , Teste de Materiais , Maleabilidade , Poliésteres/química , Polietileno/química , Polietilenotereftalatos/química , Polipropilenos/química , Estresse Mecânico , Propriedades de Superfície , Temperatura
11.
No Shinkei Geka ; 41(5): 407-13, 2013 May.
Artigo em Japonês | MEDLINE | ID: mdl-23648657

RESUMO

Infected subdural hematoma(ISH)is a rare disease caused by hematogenous infection of a preexisting subdural hematoma. We report a rare case of ISH accompanied by cerebral infarction. A 76-year-old man who had suffered a closed head injury 3 months before presented fever, headache and left hemiparesis during the medical treatment of acute cholangitis and obstructive jaundice with pancreatic cancer at the department of surgical gastroenterology. At the consultation, computed tomography(CT)scan indicated right chronic subdural hematoma. We performed a burr hole opening surgery on the same day. Abscess and hematoma was aspirated from the subdural space, and methicillin-resistant Staphylococcus aureus(MRSA)was detected in this specimen. Thus the diagnosis of the infected subdural hematoma was confirmed. However, despite the antibiotics therapy, follow-up CT showed a low-density area close to the residual abscess, which suggested cerebral infarction. Cerebral angiography showed a vasospasm at the cortical segment of the right middle cerebral artery near the residual abscess. Eventually we carried out a small craniotomy to evacuate the abscess. Our case showed that prompt surgical treatment is required in case of ISH and the whole hematoma and abscess should be removed as soon as possible with an image diagnosis and an additional surgical operation.


Assuntos
Infarto Cerebral/cirurgia , Hematoma Subdural/cirurgia , Infecções Estafilocócicas/complicações , Staphylococcus aureus/isolamento & purificação , Idoso , Infarto Cerebral/complicações , Infarto Cerebral/diagnóstico , Craniotomia/métodos , Hematoma Subdural/complicações , Hematoma Subdural/diagnóstico , Humanos , Masculino , Resistência a Meticilina , Infecções Estafilocócicas/microbiologia , Espaço Subdural/cirurgia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
12.
Polymers (Basel) ; 15(8)2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37111969

RESUMO

This in vitro study aimed to evaluate the hardness and color change of an ethylene-vinyl-acetate copolymer (EVA) material for mouthguards after exposition to different cleaning agent solutions and isotonic drinks. Four hundred samples were prepared and divided into four equinumerous groups (n = 100), in which there were 25 samples from each color of EVA (red, green, blue and white). The hardness, using the digital durometer, and the color coordinates (CIE L*a*b*), using the digital colorimeter, were measured before the first exposition and after 3 months of exposition to spray disinfection and incubation in the oral cavity temperature, or immersion in isotonic drinks. The values of Shore A hardness (HA) and color change (ΔE-calculated by Euclidean distance) were statistically analyzed using the Kolmogorov-Smirnov test, multiple comparison ANOVA/Kruskal-Wallis and appropriate post-hoc tests. Statistically significant changes in color and hardness between the tested groups were demonstrated after the use of agents predestined for disinfecting the surface of mouthguards on the tested samples. There were no statistically significant differences in color and hardness between the groups immersed in isotonic sport drinks potentially consumed by competitors practicing combat sports using mouthguards. Despite the changes in color and hardness after the use of disinfectants, the deviations were minor and limited to specific colors of the EVA plates. The intake of isotonic drinks practically did not change either the color or the hardness of the samples, regardless of the tested color of the EVA plates.

13.
No Shinkei Geka ; 40(2): 121-8, 2012 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-22281464

RESUMO

Dural and perimedullary arteriovenous fistula (AVF) at the craniocervical junction tend to cause subarachnoid hemorrhage (SAH). However, their natural history and clinical manifestations still remain to be elucidated. From 2003 to 2009, we encountered 5 cases of dural and perimedullary AVF presented with SAH. They were all male, ranging in age from 53 to 85 year-old (mean: 68 year-old). Rebleeding occurred in 1 patient on day 11. Outcome estimated by modified Rankin Scale did not change remarkably from 2.6 on admission to 2.4 at 3 months later on average. Cerebral angiography and 3D-CT angiography disclosed feeders originating from radicular or intracranial vertebral arteries which drained into the epidural venous plexus or spinal meningeal veins. One patient died of systemic complication during his clinical course. Thus we performed open surgery in the remaining 4 patients. Of these, we failed to occlude feeders completely in the initial surgery without intraoperative digital subtraction angiography (DSA) in 2 patients. Following this treatment we performed coil embolization and repeated open surgery with the aid of intraoperative DSA, respectively. In 1 patient out of the remaining 2 patients, we utilized intraoperative DSA to confirm complete disappearance of AVF composed of multiple feeders. These observations show that SAH caused by dural and perimedullary AVF at the craniocervical junction should be mainly treated by open surgery with the aid of intraoperative DSA in order to accomplish obliteration of the feeders because, otherwise, we might fail to confirm complete disappearance of AVF.


Assuntos
Fístula Arteriovenosa/diagnóstico , Malformações Vasculares do Sistema Nervoso Central/diagnóstico , Hemorragia Subaracnóidea/etiologia , Idoso , Idoso de 80 Anos ou mais , Angiografia Digital , Fístula Arteriovenosa/cirurgia , Malformações Vasculares do Sistema Nervoso Central/cirurgia , Angiografia Cerebral , Vértebras Cervicais , Embolização Terapêutica , Humanos , Masculino , Bulbo , Pessoa de Meia-Idade , Crânio
14.
Artigo em Inglês | MEDLINE | ID: mdl-36293631

RESUMO

BACKGROUND: A delay in muscle repair interferes with the effect of training or exercise; therefore, it is important to identify the factors that delay muscle repair. P. gingivalis, one of the most common periodontal disease pathogens, has the potential to inhibit muscle repair after training, as inferred from a previous study. To assess the expression of satellite cells in this in vivo study, we evaluated the relationship between P. gingivalis and muscle regeneration after training. METHODS: A total of 20 male Wistar rats (eight weeks in age) were randomly divided into two groups: one orally administered sonicated P. gingivalis four times per week for six weeks (PG group) and one given no treatment (NT group). After four weeks of training using a treadmill, the gastrocnemius was evaluated using histology of the cross-sectional area (CSA) of myotubes and immunohistochemistry of the expression of skeletal muscle satellite cells. In addition, an endurance test was performed a day before euthanization. RESULTS: The CSA and expression of Pax7+/MyoD- and Pax7+/MyoD+ cells were not significantly different between the groups. However, the expression of Pax7-/MyoD+ cells and running time until exhaustion were significantly lower in the PG group. CONCLUSIONS: Infection with P. gingivalis likely interferes with muscle repair after training.


Assuntos
Condicionamento Físico Animal , Células Satélites de Músculo Esquelético , Animais , Masculino , Ratos , Administração Oral , Fibras Musculares Esqueléticas , Músculo Esquelético/metabolismo , Ratos Wistar , Células Satélites de Músculo Esquelético/metabolismo
15.
Front Psychol ; 13: 852866, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35529561

RESUMO

Introduction: Wind instrument players sometimes suffer from erosion of the mucous membrane of the lip. This is caused by the action and pressure of the mouthpiece of the wind instrument against teeth. To address this problem, a lip shield is fitted over the dental arch to prevent direct contact between the lips and teeth. However, there are a few studies on the influence of the lip shield on the acoustics of wind instruments. The purpose of this study was to analyze the psychoacoustics of a clarinet performance with the player wearing a custom-made soft lip shield to prevent mucosal erosion of the lower lip. Case Description: A lip shield was custom-made with a soft thermoplastic material for a female clarinetist who complained of mucosal erosion and pain of the lower lip. The psychoacoustics of her musical performance played in different dynamics, fortissimo, mezzo forte and pianissimo were analyzed, including loudness and sharpness. A self-evaluation questionnaire with items rated on a 10-point scale was administered. After wearing the lip shield, the patient reported that the mucosal erosion and pain of her lower lip when playing clarinet resolved. The lip shield had little effect on the loudness. There was a slight decrease in sharpness when the lip shield was worn compared to when it was not, describing the reduction of high frequencies. Furthermore, fewer variations in sharpness between the tones were observed. Conclusion: The results suggest that lip shields made of soft materials can eliminate mucosal erosion and pain of the lower lip while having little effect on performance, although, a slight change in timbre is possible.

16.
J Dent Sci ; 17(1): 308-315, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35028052

RESUMO

BACKGROUND/PURPOSE: Custom-made mouthguards (MGs) are strongly recommended for athletes during sports activities to prevent dental injuries. Athletes undergoing orthodontic treatment and wearing brackets require specially designed MGs for better protection and to create more space that will not hinder the planned orthodontic tooth movement. The purpose of this study was to fabricate effective, specially designed, custom-made MGs for patients or athletes with ongoing orthodontic treatment and to evaluate the shock absorption abilities of these MGs by an in vitro comparison of three different designs. MATERIALS AND METHODS: Three different types of specially designed, double-layered MGs, (i) creating inter bracket space inside the MG, (ii) embedding silicon wax inside the MG, and (iii) creating a buffer space with additional hard insertion, were fabricated from a simulated bracket attached model. Impact test was performed using a free-falling object on a vertical rod, and the strain-gauge system was used to assess the strain on the dentition with the MGs for the comparison of the shock absorption abilities of the three types. Analysis of variance at a significance level of 5% and multiple comparisons were performed for statistical analysis. RESULTS: The strains on the dentition with the MG creating buffer space with hard insertion were significantly lower than those with the other two types of MG (P < 0.001). CONCLUSION: Insertion of a hard material and ensuring buffer space between the MG and the teeth and/or appliance was more effective than other methods of fabricating custom-made MGs to prevent sports-related traumatic dental injuries in athletes undergoing orthodontic treatment.

17.
Acta Neurol Belg ; 111(3): 213-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22141285

RESUMO

In the developed countries, especially Japan, elderly population is rapidly increasing, but outcomes of elderly patients with the age of 80 years and older suffering from subarachnoid hemorrhage (SAH) remain still unclear. We retrospectively reviewed the medical records of nontraumatic SAH patients aged 80 years and older, who were hospitalized in a single center between 1998 and 2009. There were 28 patients (80-90 years old and 75% female), representing 5.9% of all non-traumatic SAHs (n = 474). Of those, 16 patients received an intervention (ten clipping and six endovascular coiling) and the remaining 12 patients were managed conservatively. The median survival time of intervention group was 110 days and that of conservative group 49 days (p = 0.12, log rank analysis). Cox's proportional hazards model yielded two variables, the Japan Coma Scale (JCS) grade on admission ( hazard ratio: 2.93 [p = 0.009]) and conservative treatment (hazard ratio: 2.14 [p = 0.054]). In the outcome of the modified Rankin Scale between these two groups, logistic regression analysis had significant variable; the JCS grade on admission (odds ratio: 280, [p = 0.020]). In the elderly patients with good initial clinical condition, an acute intervention may have good outcome.


Assuntos
Índice de Gravidade de Doença , Hemorragia Subaracnóidea/mortalidade , Hemorragia Subaracnóidea/patologia , Centros Médicos Acadêmicos/estatística & dados numéricos , Idoso de 80 Anos ou mais , Embolização Terapêutica/mortalidade , Feminino , Humanos , Japão/epidemiologia , Masculino , Procedimentos Neurocirúrgicos/mortalidade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Hemorragia Subaracnóidea/terapia , Resultado do Tratamento
18.
Aviat Space Environ Med ; 82(4): 442-7, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21485402

RESUMO

INTRODUCTION: High positive acceleration (+Gz) stress is known to cause cerebral hypoperfusion, resulting in brain insults. Muscular contraction is reported to induce a pressor response. The effects of teeth clenching on cerebral hypoperfusion were examined. METHODS: The masseter muscle of anesthetized Sprague-Dawley rats was electrically stimulated to cause maximum clenching of the teeth. Arterial pressure at the level of the brain (APBr), heart rate, and central venous pressure were measured when rats were exposed to +1.5 Gz by using a centrifuge without an anti-C system. RESULTS: Acceleration of +1.5 Gz decreased APBr by 18.3 +/- 2.0 mmHg, which was reduced to 1.9 +/- 2.0 mmHg by masseter muscle contraction, but was not reduced by femoral muscle contraction. Stimulation of the masseter muscle but not the femoral muscle induced a pressor response of 11.8 +/- 2.1 mmHg, which was eliminated by dantrolene, a postsynaptic skeletal muscle relaxant. When masseter contraction was blocked by dantrolene, masseter stimulation did not reduce cerebral hypotension in the presence of +1.5-Gz acceleration (delta 18.9 +/- 2.6 mmHg). CONCLUSION: Our results suggest that teeth clenching induced a pressor response that prevented +Gz-induced cerebral hypotension, which suggests the possible development of a new anti-G method.


Assuntos
Aceleração , Bruxismo/fisiopatologia , Artérias Cerebrais/fisiologia , Hipotensão/fisiopatologia , Animais , Pressão Sanguínea , Frequência Cardíaca , Músculo Masseter/fisiologia , Ratos , Ratos Sprague-Dawley
19.
Dent Mater J ; 40(6): 1338-1344, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33828002

RESUMO

The purpose of this study was to evaluate the application of fiberglass reinforcement method in thermoplastic mouthguard materials to improve flexural properties and adhesive strength. Commonly used two types of commercial mouth guard materials (ethylene-vinyl acetate copolymer-based and polyolefin-based) were reinforced with glass fiber clothes by two-step hot press. Flexural strength and adhesive strength with each base material were examine via three-point bending test and delamination test, respectively. Ethylene-vinyl acetate copolymer-based fiberglass-reinforced material has significantly greater adhesive strength with base material and improvement of flexural properties compared with polyolefin-based material. These results suggest that flexural properties of both conventional commercial mouthguard materials were improved when the glass-fiber-reinforced method was applied to reinforce mouthguard materials, and more, ethylene-vinyl acetate copolymer was more desirable for the base material.


Assuntos
Resistência à Flexão , Protetores Bucais , Vidro , Teste de Materiais , Maleabilidade , Estresse Mecânico
20.
J Prosthodont Res ; 65(2): 261-265, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32938853

RESUMO

PURPOSE: Wearing a sports mouthguard is not only recommended in collision sports, such as American football, boxing, and rugby football, but also in low-contact sports, such as basketball, handball, and soccer. It is recommended to remove oral prosthetic devices while playing sports to avoid the risk of fracturing the device. However, players with maxillectomy must wear obturator-type prosthetic devices for speech, breathing, and deglutition even while playing sports. Therefore, there is a need for an oral appliance to prevent dental injury while playing sports without the risk of fracturing the device for players who have undergone maxillectomy.In this case, we fabricated and proposed overlay-type and obturator-type customized sports mouthguards for a patient who had undergone maxillectomy and assessments of satisfaction, speech intelligibility, nasopharyngeal closure function, and swallowing function while playing soccer. RESULTS: The patient was only satisfied with the obturator-type mouthguard, and the results of the speech intelligibility, nasopharyngeal closure function, and swallowing tests using the obturator-type mouthguard showed no differences compared to those associated with the previously used prosthetic device. CONCLUSIONS: This case may help highlight the importance of providing obturator-type mouthguards for players who have undergone maxillectomy to prevent dental injury and physical and mental discomfort.


Assuntos
Protetores Bucais , Esportes , Humanos , Satisfação Pessoal , Inteligibilidade da Fala
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