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1.
IEEE Trans Biomed Eng ; 71(5): 1705-1716, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38163303

RESUMO

OBJECT: The purpose of this study is to develop an image artifact removal method for radar-based microwave breast imaging and demonstrates the detectability on excised breast tissues of total mastectomy. METHODS: A cross-correlation method was proposed and measurements were conducted. A hand-held radar-based breast cancer detector was utilized to measure a breast at different orientations. Images were generated by multiplying the confocal image data from two scans after cross-correlation. The optimum reconstruction permittivity values were extracted by the local maxima of the confocal image intensity as a function of reconstruction permittivity. RESULTS: With the proposed cross-correlation method, the contrast of the imaging result was enhanced and the clutters were removed. The proposed method was applied to 50 cases of excised breast tissues and the detection sensitivity of 72% was achieved. With the limited number of samples, the dependency of detection sensitivity on the breast size, breast density, and tumor size were examined. CONCLUSION AND SIGNIFICANCE: The detection sensitivity was strongly influenced by the breast density. The sensitivity was high for fatty breasts, whereas the sensitivity was low for heterogeneously dense breasts. In addition, it was observed that the sensitivity was high for extremely dense breast. This is the first detailed report on the excised breast tissues.


Assuntos
Neoplasias da Mama , Mama , Mastectomia , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Mastectomia/métodos , Mama/diagnóstico por imagem , Mama/cirurgia , Imageamento de Micro-Ondas , Microscopia Confocal/métodos , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Adulto , Artefatos , Algoritmos , Idoso
2.
Front Psychiatry ; 14: 1304215, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38173706

RESUMO

Background: Schizophrenia is a major mental disorder, with an estimated incidence of 1%. Since they are sensitive to sensory changes, orthodontic treatment to move teeth should be avoided as aggressively as possible in these patients because of strong concerns about the possibility of causing adverse psychological effects, thus there are few reports on orthodontic treatment for schizophrenia patients. We report a case of severe open bite caused by medication after the onset of schizophrenia, even though the patient's occlusion had been stable for a long time after surgical orthodontic treatment. Medication control and the use of a minimally invasive orthodontic appliance improved the occlusion without adversely affecting the patient's mental health. Case: A 22-year-old woman presented to the clinic with a chief complaint of an anterior open bite. Intraoral findings showed an overbite (vertical overlap of the incisor teeth) of -3.0 mm and an overjet (horizontal overlap of the incisor teeth) of -0.5 mm. The preoperative orthodontic treatment included bilateral extraction of the maxillary first premolars. Subsequently, orthognathic surgery was performed to achieve a harmonized skeletal relationship and occlusion. Occlusion was stable for 3 years after surgery. However, 10 years after surgery, the patient returned to the clinic complaining of an anterior open bite (overbite = -4.0 mm). Six years prior to the return, the patient was diagnosed with schizophrenia. We thought that ignoring the patient's strong desire to treat her open bite might also cause psychological problems; therefore, in addition to medication control, we treated her using a minimally invasive removable orthodontic appliance (retainer with tongue crib). Her anterior open bite improved (overbite, +1.0 mm) to within the normal range. Conclusion: In this case, medication control was thought to be essential to improve her drug-induced open bite. However, minimally invasive orthodontic treatment, such as the use of a removable appliance, might be helpful in promoting her mental stability as well as for improving occlusion. Careful support is required to obtain information about the patient's mental state and medications through close cooperation with psychiatrists.

3.
Prog Orthod ; 23(1): 50, 2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36577877

RESUMO

BACKGROUND: Investigating the morphological and functional effects on mandibular asymmetry (MA) is important not only to understand the developmental process of masticatory dysfunction, but also to provide suggestions for evidence-based occlusal treatment. AIM: To evaluate three-dimensional temporomandibular joint (TMJ) morphology and its relationship to asymmetrical condylar movement in MA patients. MATERIALS AND METHODS: Fifty subjects were divided into MA and control groups (n = 25 each) according to a menton deviation of 4 mm from the mid-sagittal plane. TMJ morphology (condyle, glenoid fossa and TMJ spaces) were evaluated using a three-dimensional analysis programme. Three-dimensional condylar movements (from the sagittal and horizontal planes) were recorded and measured by computerized axiography on protrusion. Side-to-side asymmetry was measured for each parameter. The asymmetry index value was calculated to assess the correlation between TMJ morphology and condylar movement. For the statistical analysis, Wilcoxon's signed-ranked test, the Mann-Whitney U test, and Spearman's rank correlation were used. RESULTS: Glenoid fossa volume, surface area, anteroposterior length, and condylar volume were significantly smaller, and articular eminence angle, glenoid fossa, and condylar axial angle were significantly larger, on the shifted side of the MA group when compared with those on the non-shifted side and the mean values of the control group (P < 0.05). The TMJ spaces of the MA group showed no bilateral difference but were significantly narrower in the medial, superior, and anterior joint spaces when compared with the control group (P < 0.05). Condylar path length and sagittal condylar inclination were significantly asymmetrical. The asymmetry index of the condyle volume was significantly correlated with that of the condylar path length (P = 0.005). The asymmetry index of the glenoid fossa volume and the articular eminence angle were significantly correlated with that of the sagittal condylar inclination (P = 0.009 and P = 0.002, respectively), and the asymmetry index of glenoid fossa volume was significantly correlated with the bilateral transverse condylar inclination (P = 0.006 and P = 0.016, respectively). CONCLUSIONS: Morphological asymmetry of the TMJ is significantly different between the shifted and non-shifted sides and is closely related to functional asymmetry of condylar movement in MA patients. (350/350).


Assuntos
Assimetria Facial , Côndilo Mandibular , Humanos , Assimetria Facial/diagnóstico por imagem , Mandíbula/diagnóstico por imagem , Côndilo Mandibular/diagnóstico por imagem , Movimento , Articulação Temporomandibular/diagnóstico por imagem
4.
Eur J Orthod ; 44(3): 294-302, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34546345

RESUMO

OBJECTIVES: Understanding the mechanism of mandibular asymmetry (MA) is important to provide suggestions for occlusal treatment and to know the developmental process of masticatory dysfunction. To investigate the morphological and functional effects on MA, we evaluated the three-dimensional position of the glenoid fossa and its relationship to asymmetrical condylar translational movement. METHODS: In this retrospective study, 50 subjects who previously underwent computed tomography for surgical purposes were divided into MA and control groups according to a menton deviation of at least 4 mm from the mid-sagittal plane. The glenoid fossae positions were evaluated using a three-dimensional analysis program. Condylar translational movements were recorded and measured by computerized axiography on protrusion. Side-to-side asymmetry was measured for each parameter. Asymmetry index value was calculated to assess the correlation between glenoid fossa position and condylar movement. Wilcoxon's signed-ranked test, Mann-Whitney U-test, and Spearman's rank correlation were used for the statistical analysis. RESULTS: In the MA group, glenoid fossa position on the shifted side was significantly inferior and posterior as compared to that on the non-shifted side and of the control group. Condylar path length and sagittal condylar inclination were significantly greater on the shifted side versus non-shifted side, while no significant difference was found in transverse condylar inclination. The asymmetry index of the anterior-posterior glenoid fossa position was significantly correlated with that of condylar path length and bilateral transverse condylar inclination. In the control group, there were no significant correlations among the morphological and functional parameters. LIMITATIONS: This study did not consider muscle activity and disc position, which may affect condylar movement. CONCLUSIONS: Functional asymmetry of condylar translational movements is closely related to asymmetry of glenoid fossa position in MA patients.


Assuntos
Cavidade Glenoide , Cavidade Glenoide/diagnóstico por imagem , Humanos , Mandíbula/diagnóstico por imagem , Côndilo Mandibular/diagnóstico por imagem , Estudos Retrospectivos , Articulação Temporomandibular , Tomografia Computadorizada por Raios X
5.
Sensors (Basel) ; 18(11)2018 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-30404177

RESUMO

Limitations of optical devices for motion sensing such as small coverage, sensitivity to obstacles, and privacy exposure result in the need for improvement. As motion sensing based on radio frequency signals is not constrained by the limitation above, channel state information (CSI) from Wi-Fi devices could be used to improve sensing performance under the above circumstances. Unfortunately, CSI phase cannot be practically obtained due to the temporal phase rotation generated from Wi-Fi chips. Therefore, it would be rather complicated to realize motion analysis, especially the direction of motion. To mitigate the issue, this paper proposes a CSI calibration method that employs a back-to-back channel between Wi-Fi transceivers for phase rotation removal while preserving the original CSI phase. Through experiment, calibrated CSI showed a high similarity to the channel without phase rotation measured using a Vector Network Analyzer (VNA). Another experiment was conducted to observe Doppler frequency due to simple hand gestures using the Wavelet transform. A visual analysis revealed that the Doppler frequency of calibrated CSI could correctly capture the motion pattern. To the best of the authors' knowledge, this is the first calibration method that maintains the original CSI and is applicable for in-depth motion analysis.

6.
Prog Orthod ; 19(1): 45, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30417234

RESUMO

BACKGROUND: Deglutitive motion of the tongue may function to maintain tooth position. However, the causation between abnormal patterns of orofacial muscle function and dental malocclusion remains unclear. To clarify the pathogenic mechanism of malocclusion, it is important to determine the relative positional relationship between the tongue tip and incisor edge or the dorsal tongue and palate during deglutition. Here, we assessed the utility of 3-T segmented cine-magnetic resonance (MR) imaging, combined with static MR images for hard tissue visualization, in assessing the relationship between the tongue and the surrounding tissues during deglutitive tongue movement. METHODS: Cine-MR images were acquired from three healthy female volunteers during deglutition who had no history of swallowing disorder or other chronic illness, normal alignment and occlusion, and a skeletal class I relationship. Three cine-MR images were taken during deglutition in accordance with an auditory cue for each volunteer. During static imaging, custom-made, contrast-medium-filled clear retainers were positioned in the mouth to allow visualization of the upper and lower incisors and hard palate boundaries. Static images were superimposed onto images of the three stages in deglutitive tongue movement, which were selected from a series of cine-MR images. These superimpositions were assessed five times by tracing cephalometric parameters to examine the reproducibility of the method. RESULTS: Traces varied little across repeated measurements, and all subjects had a similar pattern of dorsal tongue movement. Tongue-to-palate contact increased slightly during the first to second stage of swallowing and abruptly increased during the second to third stage, while the tongue tip position remained constant. CONCLUSIONS: Segmented cine-MR imaging combined with static MR images is useful for assessing soft tissue motion during deglutition. This method is particularly useful in dentistry to evaluate the relationship between tongue function and maxillofacial morphology in terms of orthodontic treatment and orofacial myofunctional therapy, and for improving tongue movement during speech therapy.


Assuntos
Deglutição , Imagem Cinética por Ressonância Magnética , Movimento , Língua/diagnóstico por imagem , Língua/fisiologia , Adulto , Cefalometria , Feminino , Humanos , Má Oclusão/fisiopatologia , Valores de Referência
7.
Prog Orthod ; 19(1): 38, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30270414

RESUMO

BACKGROUND: The purpose of this cross-sectional study was to investigate the effects of congenitally missing teeth on craniofacial morphology and to characterize the features of maxillofacial morphology of oligodontia patients associated with individual skeletal maturity by assessment with the cervical vertebrae maturation (CVM) method. METHODS: A total of 106 non-syndromic Japanese patients with congenitally missing teeth (except for third molars) were selected and categorized into two groups according to the severity of congenitally missing teeth (hypodontia group, 1-5 missing teeth [n = 56]; oligodontia group, ≥ 6 missing teeth [n = 50]). A control group included orthodontic patients without either skeletal disharmony or congenitally missing teeth (n = 63). Subjects in oligodontia and control groups were further categorized into two subgroups on the basis of cervical stage (CS): stage I (CS2 or 3; n = 27 and n = 31, respectively) and stage II (CS4 or above; n = 23 and n = 32, respectively). Lateral cephalograms were analyzed by using eight angular and eight linear measurements. Z-scores were formulated on the basis of age and sex and were matched to the Japanese norm. Tukey tests and t tests were performed. RESULTS: Compared with the control group, the hypodontia group had significantly smaller U1 to FH plane angle and A-B plane angle; U1-L1 was significantly larger. The oligodontia group had significantly smaller ANS-Me, L1 to mandibular plane angle, and Ptm-A; U1-L1 was significantly larger. At stage I, the oligodontia group had significantly smaller ANS-Me, gonial angle, and ANS-U1. At stage II, the oligodontia group had significantly smaller U1 to FH plane angle, L1 to mandibular plane angle, Ptm-A, and Go-Pog; it also had significantly larger U1-L1. CONCLUSIONS: The present study suggested that skeletal patterns differ along with the number of congenitally missing teeth and that, in oligodontia patients, skeletal patterns differ before and after growth peak. It is important to consider the skeletal characteristics of tooth agenesis patients when designing a treatment plan.


Assuntos
Anodontia/patologia , Ossos Faciais/patologia , Desenvolvimento Maxilofacial , Adolescente , Anodontia/etnologia , Povo Asiático , Cefalometria/métodos , Estudos Transversais , Ossos Faciais/crescimento & desenvolvimento , Feminino , Humanos , Masculino , Mandíbula/crescimento & desenvolvimento , Mandíbula/patologia , Adulto Jovem
8.
Prog Orthod ; 19(1): 30, 2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-30123921

RESUMO

BACKGROUND: Tooth agenesis can involve one or more congenitally missing teeth (CMT) and is the most common congenital dental anomalies in humans. Tooth agenesis and reduction of mesiodistal tooth width are reportedly associated, suggesting that the pathogenesis of the two conditions is related. The current study analyzed the frequency of tooth agenesis and mesiodistal tooth width in cases of hypodontia (1-5 CMT) and oligodontia (≥ 6 CMT) in Japanese patients based on the hypothesis that reductions in mesiodistal tooth width are more frequently associated with oligodontia than hypodontia. METHODS: Japanese patients with tooth agenesis were divided into hypodontia cases (60 female and 25 male, mean age 19.6 years, mean CMT number 1.31 ± 1.65) and oligodontia cases (26 female and 25 male, mean age 14.6 years, mean CMT number 8.07 ± 2.39). Controls included patients with a skeletal class I relationship and no CMT (female and 60 male, mean age 20.8 years). Dental casts and orthopantomograms were used to analyze the CMT frequency and mesiodistal tooth width for each group. The Kruskal-Wallis test, the Mann-Whitney U test, and Spearman's rank correlation were used for statistical analysis. RESULTS: In the hypodontia group, mandibular second premolars were the most frequently missing tooth type (25.9%), followed by mandibular and maxillary lateral incisors (19.4 and 17.1%, respectively). In the oligodontia group, mandibular second premolars were the most frequently missing tooth type (88.2%), followed by maxillary second premolars (87.3%) and first premolars (63.7%). In female subjects in the hypodontia group, only maxillary lateral incisors and mandibular first molars were significantly smaller than those of the female control subjects. In contrast, in the oligodontia group, more tooth types were significantly smaller than those of the control, for both sexes. Except for maxillary second premolars in female subjects, correlations were apparent for all tooth types in both sexes. CONCLUSIONS: Compared to hypodontia, more tooth types exhibited reduced mesiodistal tooth width in oligodontia. Correlations between CMT number and mesiodistal tooth width support the hypothesis that reduction of mesiodistal tooth width are more frequently observed in Japanese oligodontia patients than in Japanese hypodontia patients.


Assuntos
Anodontia/patologia , Dente/patologia , Adolescente , Dente Pré-Molar/anormalidades , Feminino , Humanos , Incisivo/anormalidades , Japão , Masculino , Adulto Jovem
10.
Eur J Orthod ; 40(3): 304-311, 2018 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-29016842

RESUMO

Background/Objectives: The peri-oral muscles-including orbicularis oris-are critical in maintaining equilibrium in tooth position. Lip incompetence (LI) can thus be a factor in malocclusion. We therefore aimed to validate a technique to evaluate not only muscle activity via electromyography (EMG) but also muscle endurance and fatigue via blood flow (BF) for LI. Subjects/Methods: Subjects were classified into increased muscle tension/lip incompetent (experimental) and normal muscle tension/lip competent (control) groups. Each subject then exerted force on a custom-made traction plate connected to a tension gauge. Using laser speckle imaging and electromyographic measurements, we characterized muscle activity and corresponding BF rates in these subjects in various states of resting, loading, and recovery. Results: Results showed a significant difference between the experimental and control groups, notably in the rate of change in BF to the inferior orbicularis oris muscle under conditions of increasing load (graded exertion). Furthermore, the data suggested that the muscles in the control group undergo a more prolonged (and therefore presumably more complete) recovery than muscles in the experimental group. These factors of reduced BF and short recovery may combine to accelerate muscle fatigue and produce LI. Limitations: The sample used here was controlled for malocclusion (including open bite) to eliminate this type of confounding effect. Conclusions/Implications: From these findings, we conclude that reduced BF and inadequate recovery in the orbicularis oris muscles may be more significant than EMG activity in the assessment of LI.


Assuntos
Músculos Faciais/fisiopatologia , Lábio/fisiopatologia , Adulto , Estudos de Casos e Controles , Estudos Transversais , Eletromiografia/métodos , Músculos Faciais/irrigação sanguínea , Feminino , Humanos , Fluxometria por Laser-Doppler/métodos , Masculino , Má Oclusão/fisiopatologia , Fadiga Muscular/fisiologia , Esforço Físico/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Adulto Jovem
11.
Am J Orthod Dentofacial Orthop ; 151(2): 324-334, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28153162

RESUMO

INTRODUCTION: The purpose of this study was to evaluate the hypothesis that 3-dimensional mandibular morphology is correlated with condylar movement in patients with mandibular asymmetry. METHODS: Subjects were classified into 2 groups (n = 25 each): mandibular asymmetry with a menton deviation greater than 4 mm and no mandibular asymmetry with a menton deviation less than 4 mm. Linear and volumetric measurements of 3-dimensional mandibular morphology were recorded using computed tomography. Mandibular functional movement was recorded by computerized axiography (CADIAX; Gamma Dental, Klosterneuburg, Austria), and condylar path length, sagittal condylar inclination, and transverse condylar inclination on protrusion were measured. We calculated side-to-side asymmetry (shifted side vs nonshifted side) in mandibular morphology and assessed condylar movement by using an asymmetry ratio (nonshifted side/shifted side). RESULTS: Significant differences in mandibular morphology and condylar movement were found between the 2 groups. In the group with menton deviation greater than 4 mm, significant correlations were found between the asymmetry ratio of mandibular morphology and condylar movement: ie, condylar path length and transverse condylar inclination. No significant correlations were found between any of these measurements in the group with menton deviation less than 4 mm. CONCLUSIONS: In support of our hypothesis, the results suggested that 3-dimensional mandibular morphologic asymmetry is associated with condylar movement in subjects with mandibular asymmetry.


Assuntos
Imageamento Tridimensional , Anormalidades Maxilomandibulares/diagnóstico por imagem , Anormalidades Maxilomandibulares/fisiopatologia , Côndilo Mandibular/diagnóstico por imagem , Côndilo Mandibular/fisiopatologia , Movimento , Tomografia Computadorizada por Raios X , Adulto , Feminino , Humanos , Masculino , Mandíbula/anormalidades , Adulto Jovem
12.
Eur J Orthod ; 38(5): 525-31, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26584843

RESUMO

BACKGROUND/OBJECTIVES: Although the electromyographic (EMG) activity of the perioral muscles, including the orbicularis oris and mentalis muscles, has been described in individuals with lip incompetence during lip sealing, blood flow through these muscles remains to be elucidated. The purpose of this study was to examine the blood flow associated with EMG activity in the perioral muscles using laser speckle imaging in individuals with lip incompetence. SUBJECTS/METHODS: Blood flow and EMG activity of the superior and inferior orbicularis oris and mentalis muscles were measured with the lips in contact (C condition) and apart (O condition) in lip incompetence (experimental) and control subjects (n = 15 in each group; mean age: 29.5 years). The change ratios of blood flow and EMG activity in the C condition versus O condition (C/O ratios) were calculated and plotted in a scattergram. The Mann-Whitney U-test, Wilcoxon signed-rank test, discriminant analysis using the Mahalanobis generalized distance, and Spearman correlation were used for statistical analysis. RESULTS: In the experimental group, blood flow and EMG activity in all muscles were significantly greater in the C condition than in the O condition. The plots of C/O ratios in the experimental group showed a distinct and wide distribution and were significantly different than those in the control group. In both groups, a significant positive correlation was observed between blood flow and EMG activity in the mentalis muscle. CONCLUSIONS/IMPLICATIONS: The present findings suggest that observing blood flow in the mentalis muscle is an effective and easily performed method of evaluating lip incompetence.


Assuntos
Músculos Faciais/irrigação sanguínea , Músculos Faciais/fisiopatologia , Lábio/fisiopatologia , Adulto , Estudos de Casos e Controles , Eletromiografia/métodos , Feminino , Humanos , Fluxometria por Laser-Doppler/métodos , Masculino , Fluxo Sanguíneo Regional , Adulto Jovem
13.
Eur J Orthod ; 37(1): 22-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25150274

RESUMO

BACKGROUND/OBJECTIVES: Although it has been suggested that adult patients with facial asymmetry with posterior unilateral crossbite (PUXB) may have a more tilted mandibular hinge axis (MHA) than those without PUXB, whether craniofacial morphology is associated with the MHA remains unclear. The purpose of this study was to compare the craniofacial morphology and MHA in adult subjects with post-growth facial asymmetry with and without PUXB. SUBJECTS/METHODS: Thirty pre-orthodontic patients (PUXB and non-PUXB groups, n = 15 each, 9 females and 6 males, mean age: 23.2 years) participated in the study. The MHA was measured by computerized axiography and duplicated on posteroanterior and submentovertex cephalometric radiographs. Morphological asymmetry was evaluated for both skeletal and dental components and positional deviation of the mandible by cephalometric analysis. The Mann-Whitney U-test and Spearman's correlation coefficient by rank were used for statistical analysis. The level of statistical significance was set at P < 0.05. RESULTS: Significant differences in both skeletal and dental components were found between the PUXB and non-PUXB groups. In both the frontal and horizontal dimensions, the inclination of the MHA towards the mandibular shifted side was greater in the PUXB group than in the non-PUXB group. CONCLUSIONS/IMPLICATIONS: The present findings suggest that facially asymmetric adult subjects with malocclusions associated with PUXB exhibit not only mandibular asymmetry but also remodelling of the condylar head and glenoid fossa that accompanies the three-dimensional shifting of the MHA.


Assuntos
Assimetria Facial/patologia , Má Oclusão/patologia , Mandíbula/patologia , Adolescente , Adulto , Cefalometria/métodos , Assimetria Facial/complicações , Feminino , Humanos , Registro da Relação Maxilomandibular , Masculino , Má Oclusão/etiologia , Estatísticas não Paramétricas , Adulto Jovem
14.
IEEE J Biomed Health Inform ; 19(2): 559-70, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24876134

RESUMO

Wireless body area networks (WBANs) are an emerging technology for realizing efficient healthcare and remote medicine for the aging society of the future. In order to improve the reliability of WBAN systems and support its various applications, channel modeling and performance evaluation are important. This paper proposes a simulation-based channel modeling for evaluating the performance of WBAN cooperative transmission schemes. The time series of path losses among seven on-body nodes are generated by the finite-difference time-domain method for seven body motions. The statistical parameters of the path loss for all the motions are also obtained. The generated path loss is then applied to the evaluation of the two-hop decode-and-forward relaying scheme, yielding an improvement in transmit power. From the evaluation of body motion, useful insights are obtained such as which relay links are more robust than others. Finally, the proposed approach is validated through comparison with a measurement-based approach.


Assuntos
Simulação por Computador , Monitorização Ambulatorial/métodos , Tecnologia de Sensoriamento Remoto/métodos , Processamento de Sinais Assistido por Computador , Tecnologia sem Fio , Marcadores Fiduciais , Cabeça/fisiologia , Humanos , Perna (Membro)/fisiologia , Modelos Teóricos , Reprodutibilidade dos Testes , Tórax/fisiologia
15.
Eur J Orthod ; 33(3): 243-9, 2011 06.
Artigo em Inglês | MEDLINE | ID: mdl-20829312

RESUMO

Although it has been suggested that an imbalance in buccolingual pressure may play a role in dental compensation of the molars and asymmetry in the mandibular dental arch in subjects with facial asymmetry, it is still unclear whether buccolingual pressure is associated with this phenomenon. Thus, the purpose of this study was to test the null hypothesis that there are no differences in cheek and tongue pressure between the shifted and non-shifted sides in 12 (8 females and 4 males, mean age: 24.9 years) subjects with facial asymmetry defined as 4 mm or more deviation of the midline in the mandibular incisors. The resting buccolingual pressure on the bilateral mandibular first molars was measured simultaneously using four miniature pressure sensors. Moreover, a postero-anterior (PA) cephalogram was used to determine the buccolingual positions and the inclination of the mandibular first molars. Wilcoxon t-, Kruskal-Wallis H-, and Mann-Whitney U-tests and Spearman correlation coefficient by rank were used for statistical analysis. Significance was set at P < 0.05. Cheek pressure was significantly greater on the shifted than that on the non-shifted side, while tongue pressure on the shifted side was significantly less than that on the non-shifted side. On the other hand, tongue/cheek pressure ratio on the shifted side was significantly less than that on the non-shifted side. There were significant differences between the shifted and non-shifted sides in the buccolingual positions and inclination of the mandibular first molars. Regardless of the side, there were significant negative correlations between the buccolingual position of the mandibular first molars and cheek pressure and significant positive correlations between the buccolingual position of the mandibular first molars and tongue/cheek pressure ratio. There were also significant negative correlations between tongue/cheek pressure ratio and inclination of the mandibular first molars on both the shifted and the non-shifted sides. Thus, the present findings reject the null hypothesis. The imbalance in buccolingual pressure in subjects with facial asymmetry appears to be related to dental compensation of the molars and mandibular asymmetry.


Assuntos
Bochecha/fisiopatologia , Assimetria Facial/fisiopatologia , Músculos Faciais/fisiopatologia , Dente Molar/fisiopatologia , Língua/fisiopatologia , Adaptação Fisiológica , Adulto , Estudos de Casos e Controles , Cefalometria , Análise do Estresse Dentário , Feminino , Humanos , Japão , Masculino , Mandíbula/fisiopatologia , Pressão , Estatísticas não Paramétricas , Adulto Jovem
16.
Angle Orthod ; 78(2): 254-61, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18251601

RESUMO

OBJECTIVE: To determine the effect of an imbalance in buccolingual pressure that may be involved in molar dental compensation in the mandible and asymmetry of the dental arch in subjects with facial asymmetry. MATERIALS AND METHODS: We performed simultaneous measurement of the buccolingual pressure on the mandibular right first molar when subjects without facial asymmetry experimentally shifted the mandible laterally. Buccolingual pressures in the rest position (RP), right-shifted position (RS), and left-shifted position (LS) were compared. Moreover, T1-weighted magnetic resonance images were obtained in RP, RS, and LS. RESULTS: Tongue pressure tended to decrease in the order LS > RP > RS, while cheek pressure tended to increase in the order LS < RP < RS. The tongue/cheek pressure ratio tended to decrease in the order LS > RP > RS. There were significant positive (in RS) and negative (in LS) correlations between displacement of the tongue and tongue pressure. CONCLUSIONS: This imbalance in buccolingual pressures in the laterally-shifted mandibular position may partly explain molar dental compensation in the mandible and asymmetry of the dental arch in subjects with facial asymmetry.


Assuntos
Assimetria Facial/fisiopatologia , Mandíbula/fisiologia , Adulto , Bochecha/fisiologia , Análise do Estresse Dentário , Humanos , Imageamento por Ressonância Magnética , Masculino , Dente Molar/fisiologia , Pressão , Língua/fisiologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-19162968

RESUMO

Wireless patient monitoring using wearable sensors is a promising application. This paper provides stochastic channel models for wireless body area network (WBAN) on the human body. Parameters of the channel models are extracted from measured channel transfer functions (CTFs) in a hospital room. Measured frequency bands are selected so as to include permissible bands for WBAN; ultra wideband (UWB), the industry, science and medical (ISM) bands, and wireless medical telemetry system (WMTS) bands. As channel models, both a path loss model and a power delay profile (PDP) model are considered. But, even though path loss models are derived for the all frequency bands, PDP model is only for the UWB band due to the highly frequency selectiveness of UWB channels. The parameters extracted from the measurement results are summarized for each channel model.


Assuntos
Redes de Comunicação de Computadores , Modelos Teóricos , Monitorização Ambulatorial/instrumentação , Eletrônica Médica , Humanos , Telemetria
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