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1.
Eur J Dent Educ ; 21(1): 22-27, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26344938

RESUMO

INTRODUCTION: The DentEd Thematic Networks (TNP) were funded from the EU to converge and harmonise the dental curricula. Forty-four dental schools participated in this visitation process between 1998 and 2002. The aim of the survey was to evaluate the implementation of the Dented outcomes in the curricula and if the concept of core competences are integrated in the curriculum. MATERIAL AND METHOD: In October 2012, questionnaires were sent out to all dental schools participated in the visitation process of Dented and Dented evolves. The main question blocs were as follows: structure of the curriculum and facilities, education of students, content and quality of education, assessment, research, European involvement and value of visit for the school. RESULTS: Twenty-five dental schools (57%) answered to the questionnaire. The responder represented 20 European countries of 22, whose schools were involved (91%). The self-assessment report was stimulating the continuation of curriculum improvement. Most of them acknowledge that major competences are essential outcome for the graduated dentist. Twelve schools (58%) rated the value of the DentEd visit with strong positive influence. DISCUSSION: The visits showed strengths, weaknesses and threats. Three-quarter of all schools implemented the European Credit Transfer System (ECTS). But most of them did not realize the unit of ECTS with modules among the Bologna process. CONCLUSION: The self-assessment report was a core issue for the continuation of curriculum improvement. The challenge for the ongoing curriculum improvement is the implementation of the module system among the Bologna recommendations.


Assuntos
Educação em Odontologia/organização & administração , Faculdades de Odontologia/organização & administração , Currículo , Europa (Continente) , União Europeia , Humanos , Relações Interinstitucionais , Inquéritos e Questionários
3.
Artigo em Alemão | MEDLINE | ID: mdl-21887619

RESUMO

The dental curriculum in Germany is still based on a concept from 1955 with some revisions in certain aspects. All groups involved are interested in a new and more current version. In doing this, the compatibility with European concepts should be a main goal. The Association for Dental Education in Europe (ADEE), to which about 160 of the 200 European dental education associations are members, is in charge of coordinating projects to create a network of European universities, which intends to harmonize higher education in Europe and to create a core curriculum for the dentistry program. Based on a visitation and evaluation program at more than 50 oral and maxillofacial surgery centers, a paper for the profiles and competencies for future European dentists was formulated for the creation of a modular curriculum, for the integration of the ECT (European Credit Transfer) system, and for quality assurance of the dentistry curriculum. Especially for the situation in Germany, consequences must be drawn for further dentistry and postgraduate educational concepts, which are not completely identical with the ADEE concepts, but which can use elements of the basic Bologna concepts.


Assuntos
Educação de Pós-Graduação em Odontologia/organização & administração , Educação em Odontologia/organização & administração , União Europeia , Programas Nacionais de Saúde , Currículo/normas , Educação em Odontologia/normas , Educação Continuada em Odontologia/organização & administração , Educação Continuada em Odontologia/normas , Educação de Pós-Graduação em Odontologia/normas , Alemanha , Humanos , Licenciamento em Odontologia/normas , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Garantia da Qualidade dos Cuidados de Saúde/normas , Faculdades de Odontologia/normas , Cirurgia Bucal/educação , Cirurgia Bucal/normas
4.
Eur J Dent Educ ; 14(4): 193-202, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20946246

RESUMO

This paper presents the profile and competences for the European Dentist as approved by the General Assembly of the Association for Dental Education in Europe at its annual meeting held in Helsinki in August 2009. A new taskforce was convened to update the previous document published in 2005. The updated document was then sent to all European Dental Schools, ministries of health, national dental associations and dental specialty associations or societies in Europe. The feedback received was used to improve the document. European dental schools are expected to adhere to the profile and the 17 major competences but the supporting competences may vary in detail between schools. The document will be reviewed once again in 5 years time. Feedback to the newly published document is welcomed and all dental educators are encouraged to draw upon the content of the paper to assist them in harmonising the curriculum throughout Europe with the aim of improving the quality of the dental curriculum.


Assuntos
Competência Clínica/normas , Odontólogos/normas , Educação em Odontologia/normas , Guias como Assunto , Atitude do Pessoal de Saúde , Comunicação , Currículo/normas , Assistência Odontológica , Relações Dentista-Paciente , Odontólogos/ética , Odontólogos/legislação & jurisprudência , Educação Continuada em Odontologia , Ética Odontológica/educação , Europa (Continente) , União Europeia , Odontologia Baseada em Evidências , Comportamentos Relacionados com a Saúde , Promoção da Saúde , Humanos , Controle de Infecções Dentárias , Competência em Informação , Relações Interprofissionais , Legislação Odontológica , Anamnese , Planejamento de Assistência ao Paciente , Equipe de Assistência ao Paciente , Odontologia Preventiva , Competência Profissional , Faculdades de Odontologia , Tecnologia Radiológica
5.
Eur J Dent Educ ; 12 Suppl 1: 92-100, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18289272

RESUMO

The aim of this report is to provide guidance to assist in the international convergence of quality assurance, benchmarking and assessment systems to improve dental education. Proposals are developed for mutual recognition of qualifications, to aid international movement and exchange of staff and students including and supporting developing countries. Quality assurance is the responsibility of all staff involved in dental education and involves three levels: internal, institutional and external. Benchmarking information provides a subject framework. Benchmarks are useful for a variety of purposes including design and validation of programmes, examination and review; they can also strengthen the accreditation process undertaken by professional and statutory bodies. Benchmark information can be used by institutions as part of their programme approval process, to set degree standards. The standards should be developed by the dental academic community through formal groups of experts. Assessment outcomes of student learning are a measure of the quality of the learning programme. The goal of an effective assessment strategy should be that it provides the starting point for students to adopt a positive approach to effective and competent practice, reflective and lifelong learning. All assessment methods should be evidence based or based upon research. Mutual recognition of professional qualifications means that qualifications gained in one country (the home country) are recognized in another country (the host country). It empowers movement of skilled workers, which can help resolve skills shortages within participating countries. These proposals are not intended to be either exhaustive or prescriptive; they are purely for guidance and derived from the identification of what is perceived to be 'best practice'.


Assuntos
Benchmarking , Educação em Odontologia/normas , Gestão da Qualidade Total , Competência Clínica , Educação Continuada em Odontologia/normas , Avaliação Educacional/normas , Medicina Baseada em Evidências , Docentes de Odontologia , Pessoal Profissional Estrangeiro/normas , Humanos , Cooperação Internacional , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Controle de Qualidade , Estudantes de Odontologia , Gestão da Qualidade Total/organização & administração
6.
J Dent Res ; 84(11): 1026-30, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16246935

RESUMO

Muscle activity and function appear to be related to ionic concentrations in the muscle. We investigated whether muscle paresis induced by injection of Botulinum toxin A (Botox) in 16-week-old pigs over a 56-day period is associated with ionic changes in the affected muscles. Tissue samples were taken from the masseter, temporalis, medial pterygoid, and geniohyoid muscles by a standardized method and used for energy-dispersive x-ray microanalysis in an environmental scanning electron microscope. The largest increase in Na(+) was measured in the right and left sides of the masseter muscle in treated animals. Additionally, a significant elevation of Na(+) was measured in the anterior part of the temporalis muscle and in the pterygoid muscle (P < 0.05). In temporalis and pterygoid muscles, an increase in sulfur in both sides of treated pigs' heads was observed. Botox((R)) has an indirect impact on ion concentrations, resulting in changes in muscle functional capacity and adaptive compensation of paretic muscle function by other muscles.


Assuntos
Microanálise por Sonda Eletrônica , Músculo Masseter/química , Músculos da Mastigação/química , Paralisia/metabolismo , Animais , Toxinas Botulínicas Tipo A/administração & dosagem , Cálcio/análise , Cloro/análise , Elementos Químicos , Magnésio/análise , Microscopia Eletrônica de Varredura , Músculos do Pescoço/química , Fármacos Neuromusculares/administração & dosagem , Fósforo/análise , Potássio/análise , Músculos Pterigoides/química , Sódio/análise , Enxofre/análise , Suínos , Músculo Temporal/química
7.
Clin Oral Implants Res ; 16(4): 425-31, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16117766

RESUMO

BACKGROUND: The primary stability of short orthodontic implants is important for anchorage. METHODS: For this study 14 cadaveric human heads were used. The stability of orthodontic implants (Straumann) with lengths of 4 and 6 mm and different localization (palatal suture or paramedially) were evaluated. The implants with length of 6 mm were only placed in the suture and primary stability was non-invasively determined with the resonance frequency (Osstell). The invasive method for the analysis of the morphometric parameters of the implant/bone contact was carried out by means of histological and radiological examinations. RESULTS: The 6 mm implants have significant better primary stability in the palatal suture as 4 mm implants paramedially (P<0.05). No differences were found between 6 and 4 mm implants in the palatal suture and between 4 mm implants in palatal suture to paramedially. The histological and radiological results demonstrate the ability to measure the implant stability by investigation of the bone offer and density around the implant. Bone structure, especially the pore size in the trabecular bone and the precision of placement may influence the stability. CONCLUSION: This study shows that the short implant gives sufficient bone fixation, independently of placement. The quality of implantation and bone structure are more important than the length of the orthodontic implant.


Assuntos
Implantes Dentários , Aparelhos Ortodônticos , Palato/cirurgia , Técnicas de Movimentação Dentária/instrumentação , Densidade Óssea , Cadáver , Suturas Cranianas/diagnóstico por imagem , Suturas Cranianas/patologia , Suturas Cranianas/cirurgia , Implantação Dentária Endóssea , Humanos , Desenho de Aparelho Ortodôntico , Palato/diagnóstico por imagem , Palato/patologia , Radiografia , Vibração
8.
Eur J Dent Educ ; 9(2): 78-84, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15811155

RESUMO

The study examined the extent of stress, burnout and health problems experienced by fourth and fifth year dental students from the three universities of Dresden, Freiburg and Bern. The objectives of the study were to: (i) identify frequent sources of stress and to report the prevalence rates of burnout and health problems in dental students, (ii) determine the rate of students suffering from severe burnout symptoms and (iii) identify stress factors related to the burnout symptoms of emotional exhaustion and depersonalization. A total of 161 dental students from Dresden, Freiburg and Bern participated in the study. They completed the Psychosocial Stress Inventory, the Maslach Burnout Inventory and the Health Survey Questionnaire. Frequent sources of stress were limitation of leisure time, examination anxiety and the transition stress that was related to the adaptation to the demands of the clinical phase of dental education. Few differences existed between the students of the fourth and the fifth study year. Study-related stress was lowest in Bern and considerably higher in Dresden. Differences of mean levels of burnout symptoms were found only for the burnout dimension of emotional exhaustion. Students from Dresden and Freiburg were more emotionally exhausted than students from Bern, students from Dresden also reported more health problems than students from Bern or Freiburg. Ten per cent of the dental students suffered from severe emotional exhaustion, 17% complained about a severe lack of accomplishment and 28% reported severe depersonalization symptoms. Forty-four per cent of the variance of emotional exhaustion was explained by study-related factors such as lack of leisure time, examination anxiety and transition stress. The only predictor of depersonalization was a lack of social integration, accounting for 3% of the variance. A lack of social integration may be an indicator of low social competence which may cause difficulties in dealing with patients adequately and therefore result in depersonalization. The results indicate a need to identify the group of students who may have insufficient social skills for dealing adequately with the patients, and to train them accordingly.


Assuntos
Educação em Odontologia , Estresse Psicológico , Estudantes de Odontologia/psicologia , Adulto , Esgotamento Profissional , Estágio Clínico , Relações Dentista-Paciente , Despersonalização , Feminino , Alemanha , Nível de Saúde , Humanos , Masculino , Fadiga Mental , Inquéritos e Questionários , Suíça , Escala de Ansiedade Frente a Teste
9.
Rofo ; 177(2): 204-9, 2005 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-15666228

RESUMO

PURPOSE: The individual jaw position is determined by the masticatory muscle among other factors. Before surgical treatment of malocclusions, thorough evaluation of the muscles is required to estimate the relapse risk. MATERIALS AND METHODS: By means of computer tomography, lateral radiographs of the skull and denture models, the relationships between morphological parameters of the masticatory muscles and the jaw bone were analyzed. Furthermore, possible causes for the extent of the malocclusion are described. RESULTS: A patient group with deep overbite was found to have significantly higher muscle densities (measured in Hounsfield units [HU]) in the medial pterygoideus muscle (59.89 +/- 3.91 HU to 48.94 +/- 4.14 HU, p < 0.01), masseter muscle, and genioglossus muscle (p < 0.05) in comparison to open bite patients. Significant differences of the muscle cross-section were measured in the masseter muscle between patients with retroclined maxillary incisors and with an open bite (5.4 +/- 0.7 cm (2) to 3.8 +/- 0.4 cm (2), p < 0.05). CONCLUSION: The results show a correlation between different jaw positions and masticatory muscles. They also suggest that the function of each muscle may be different. Additional examinations of the muscle structures are required for verification of the influence of the masticatory muscles on facial morphology.


Assuntos
Face/anatomia & histologia , Má Oclusão/diagnóstico por imagem , Mandíbula/anormalidades , Músculo Masseter/diagnóstico por imagem , Músculos da Mastigação/diagnóstico por imagem , Maxila/anormalidades , Crânio/diagnóstico por imagem , Densidade Óssea , Humanos , Arcada Osseodentária , Músculo Masseter/anatomia & histologia , Músculos da Mastigação/anatomia & histologia , Tomografia Computadorizada por Raios X
10.
J Orthod ; 31(2): 107-14, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15210926

RESUMO

OBJECTIVE: To determine if the extractions of lower primary canines are an effective procedure to relieve crowding of the labial segment. STUDY DESIGN: randomized controlled trial. Subject sample: 83 cases were collected in clinics in Italy, Germany and Wales. The groups were followed over a 2-year period. METHODS: Subjects were randomly allocated to a primary canine non-extraction or extraction group. Dental casts of the patients were collected at the start and at the recall period of the trial. The outcome measures recorded were lower incisor crowding, arch length, intermolar width, overbite, overjet, lower clinical crown heights and lower incisor inclinations. STATISTICS: The Mann-Whitney test was used to compare the differences between the extraction and non-extraction groups. RESULTS: In both groups, crowding reduced 1.27 mm in the non-extraction group and 6.03 mm in the extraction group. The difference between the 2 groups was 4.76 mm (P<0.05). The arch perimeter decreased more in the extraction group by 2.73 mm (P<0.05). As the incisor inclination stayed essentially the same, the loss in arch length was attributed to the molars moving forward. The net gain from extracting deciduous canines was 2.03 mm. CONCLUSIONS: There was a reduction in lower incisor crowding as a result of lower primary canine extraction. However, arch perimeter decreased more in the extraction group leaving less space for the eruption of the lower secondary canines.


Assuntos
Má Oclusão/terapia , Ortodontia Interceptora/métodos , Extração Dentária , Criança , Dente Canino/cirurgia , Arco Dental/anatomia & histologia , Humanos , Mandíbula , Estatísticas não Paramétricas , Extração Dentária/estatística & dados numéricos , Dente Decíduo/cirurgia , Resultado do Tratamento
11.
Biomed Tech (Berl) ; 48(10): 287-90, 2003 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-14606270

RESUMO

Load direction of applied forces, implant geometry and other biomechanical parameters lead to varying reactions in the surrounding bone structure. Three types of endosseous implant measuring 9 mm in length and 3.3 mm in diameter with and without superperiosteal step, and a threaded surface were investigated with the aid of a finite element method using the COSMOS/M 2.5 program. The load on the implant was investigated under vertical, horizontal, and diagonal forces of between 0.01 N and 100 N. Vertical loading of simple implants caused bone deformation of more than 600 mu eps. The application of the superperiosteal step clearly reduced the deformation. The largest deformations under vertical loading were observed in the trabecular bone with all 3 implant geometries. On horizontal loading the deformation shifted from the trabecular to the cortical bone and was particularly marked at the transition between the two. The smallest deformations, less than 300 mu eps, were measured at implants with a superperiosteal step under diagonal loading. The thread did not improve loading capacity. Implants with a superperiosteal step are recommended since they contribute to more rapid healing and strengthening of the bone.


Assuntos
Osso e Ossos/fisiopatologia , Osso e Ossos/cirurgia , Análise de Falha de Equipamento/métodos , Modelos Biológicos , Desenho de Aparelho Ortodôntico/métodos , Aparelhos Ortodônticos , Simulação por Computador , Elasticidade , Análise de Elementos Finitos , Humanos , Estresse Mecânico , Suporte de Carga
12.
J Dent Res ; 82(7): 570-4, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12821721

RESUMO

Muscular remodeling is known to be a prerequisite for permanent correction of mandibular-maxillary malocclusion. The objective of this study was to clarify if an increase in type I fiber number is accompanied by an increased capillary density and improved muscular blood flow. Juvenile pigs received build-ups on the molars, which induced a protrusion of 7.6 + 1.5 mm. After 4 weeks of treatment, chronic lower jaw protrusion induced a marked muscle blood flow increase in the anterior and medial regions of the superficial part of the masseter and in the medial pterygoid muscle (P < 0.05). Furthermore, an increase in capillary density and in the amount of type I fibers was found in all regions of masticatory muscles with an increased muscle blood flow (P < 0.05). Finally, the capillary-to-fiber ratio increased (P < 0.05). Muscle blood flow and capillary density showed a strong linear correlation (r = 0.89, P < 0.01). These changes suggest a complex muscle adaptation for long-term, fatigue-resistant activity during the early corrective period of mandibular-maxillary malocclusion treatment.


Assuntos
Avanço Mandibular , Músculos da Mastigação/anatomia & histologia , Músculos da Mastigação/irrigação sanguínea , Animais , Capilares/fisiologia , Imuno-Histoquímica , Fibras Musculares de Contração Rápida/fisiologia , Fibras Musculares de Contração Lenta/fisiologia , Neovascularização Fisiológica , Fluxo Sanguíneo Regional , Suínos
13.
Eur J Orthod ; 25(2): 109-15, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12737208

RESUMO

The effects of bite and orthodontic forces exerted on endosseous palatal implants are not completely understood. This applies especially to the biomechanical properties inherent in the different implant geometries and resulting bone remodelling reactions on the one hand, and to the influence on the direction and magnitude of the applied forces on the other. The results of this study should help in the selection of implants for clinical use. Three types of endosseous implants (all 9 mm in length and 3.3 mm in diameter, made of titanium) were used for this investigation. Type 1 was a simple, cylinder-shaped implant; type 2 a cylinder-shaped implant with a superperiosteal step; and type 3 a cylinder-shaped implant, subperiosteally threaded, with a superperiosteal step. The load on the implant was investigated under three conditions of bite and orthodontic forces from 0.01 to 100 N (vertically, horizontally, and diagonally). The study results were calculated by means of a finite element (FE) method. Vertical loading caused bone deformation of more than 600 microeps at the simple implant. The largest deformations at this load were found in the trabecular bone with all three implant geometries. However, trabecular bone deformation was reduced by a superperiosteal step. Horizontal loading of the implants shifted the deformation from the trabecular to the cortical bone. Furthermore, a large deformation was measured at the transition from cortical to trabecular bone. The smallest deformations (less than 300 microeps) were found for implants with a superperiosteal step and diagonal loading (type 2). The use of threads provided no improvement in loading capacity. All implant types investigated showed good biomechanical properties. However, endosseous implants with a superperiosteal step had the best biomechanical properties under low loads. Thus, the trend should be to optimize the design of implants by producing small implants with additional anchorage on the bone surface.


Assuntos
Implantes Dentários , Aparelhos Ortodônticos , Palato Duro/fisiopatologia , Fenômenos Biomecânicos , Força de Mordida , Simulação por Computador , Planejamento de Prótese Dentária , Análise de Elementos Finitos , Humanos , Modelos Biológicos , Palato Duro/patologia , Estresse Mecânico , Propriedades de Superfície , Titânio , Suporte de Carga
15.
J Orofac Orthop ; 62(5): 337-49, 2001 Sep.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-11590823

RESUMO

PATIENTS AND METHOD: The study covered 40 patients (21 boys and 19 girls) whose Class II, Division 1 malocclusion was being treated with a Klammt open activator. To illustrate growth changes, tensor analysis was used as a superimposition-free comparative technique. At the beginning of treatment for Class II correction, the boys had a mean age of 11.3 years and the girls a mean age of 10.1 years. Patients were evaluated on admission and on attaining normal occlusion. 58 boys and 63 girls participating in a growth study at Kings College School of Medicine and Dentistry, London, served as controls. RESULTS: Prior to treatment the participants suffering from Class II, Division 1 malocclusion exhibited distinct growth deficits in vertical direction. In the control group, the principal direction of mean growth was found to be anterior-inferior. Under the influence of the activator, growth was found to develop in the same direction as in the controls, so that anterior positioning of the lower jaw and an increase in lower facial height were attained.


Assuntos
Aparelhos Ativadores , Má Oclusão Classe II de Angle/terapia , Fatores Etários , Anisotropia , Cefalometria , Criança , Feminino , Humanos , Masculino , Modelos Teóricos , Fatores Sexuais , Fatores de Tempo
16.
Eur J Orthod ; 23(4): 349-54, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11544784

RESUMO

The aim of the present investigation was to identify adequate implant treatment for young patients. In an animal model palate deformation was investigated by acute quasi-static loading. Three series of tests (with newborn, young and adult pigs) were performed, each with two groups (one or two-point stress) and 5-7 animals per group. Discs with a diameter of 3 and 5 mm were placed in group 1 in the suture area, and in group 2 at both the right and left sides of the suture. Deformation was analysed by a computerized three-dimensional (3D) photo-imaging evaluation system. In young animals the one-point load at a significantly lower force level led to fractures in comparison with the two-point load (P < 0.001). Similar results were measured by an increase in the size of one disc from 3 to 5 mm (P < 0.001). In contrast, adult pigs showed stable results with both methods. In general, a larger disc diameter led to less instability. The one-point load seems to be suitable for adult animals, whereas a two-point load might be favourable during ossification. The advantage of the two-point load is the generation of a higher stress and therefore improved control of dental fixation. However, further tests are necessary to investigate the long-term effects.


Assuntos
Implantes Dentários , Aparelhos Ortodônticos , Palato Duro/fisiologia , Técnicas de Movimentação Dentária/instrumentação , Fatores Etários , Animais , Animais Recém-Nascidos , Suturas Cranianas/fisiologia , Implantação Dentária Endóssea , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Fraturas Maxilomandibulares/fisiopatologia , Modelos Animais , Desenho de Aparelho Ortodôntico , Osteogênese/fisiologia , Estatística como Assunto , Estresse Mecânico , Suínos , Suporte de Carga
17.
Exp Toxicol Pathol ; 53(2-3): 207-13, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11484841

RESUMO

Type I and type II muscle fibres have different ion concentrations. Muscles adapt to chronic stress by changing of fibre types and remodelling of the myosin heavy chains in the muscle fibres. The present investigation on ionic change during muscular contraction was carried out on 10-week-old pigs (6 treated animals, 6 controls) over a 28-day period. Six pigs received acrylic build-ups to induce mechanical advancement of the lower jaw and chronic chewing stress. Muscle tissue was taken from the masseter (M1, M2, M3), temporal (TP1, TP2), medial pterygoid (PM) and geniohyoid (GH) muscles by a standardized method. Eighty-four muscle samples were used for histological fibre differentiation with mATPase. Energy-dispersive X-ray microanalysis of muscles was carried out in an environmental scanning electron microscope. Endurance stress in the stressed muscles was seen as an increase of type I fibres (P < 0.001). This histological change and ionic alterations were measured in the anterior region of the masseter (M1 and M2) and in the posterior region of the temporal muscle (TP2). Smaller changes were found in the medial pterygoid muscle. We measured in this muscles increases in potassium, sulphur, chloride (P < 0.05) and even larger increases in phosphate (up to 1.5 mmol/g to 2.3 mmol/g, P < 0.001) and sodium (3-fold, P < 0.001). The results reveal the effects of chronic stress on muscle fibres and ion concentration in the muscle. Chronic stress resulted in an increase of type I fibres and increased ion concentration in the same muscle region. These are considered to be indicators of more efficient contraction. The changes in ion concentration are an important factor in muscle contraction.


Assuntos
Íons/metabolismo , Mastigação/fisiologia , Músculos da Mastigação/metabolismo , Animais , Microanálise por Sonda Eletrônica , Feminino , Processamento de Imagem Assistida por Computador , Íons/análise , Músculos da Mastigação/química , Microscopia Eletrônica de Varredura , Modelos Animais , Contração Muscular/fisiologia , Fibras Musculares de Contração Rápida/química , Fibras Musculares de Contração Rápida/metabolismo , Fibras Musculares de Contração Rápida/ultraestrutura , Fibras Musculares de Contração Lenta/química , Fibras Musculares de Contração Lenta/metabolismo , Fibras Musculares de Contração Lenta/ultraestrutura , Potássio/análise , Potássio/metabolismo , Sódio/análise , Sódio/metabolismo , Estresse Mecânico , Suínos
18.
Angle Orthod ; 71(4): 318-23, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11510642

RESUMO

Titanium brackets are used in orthodontic patients with an allergy to nickel and other specific substances. In recent studies, the corrosive properties of fluoride-containing toothpastes with different pH values were investigated. The present in vivo study tested how the surfaces of titanium brackets react to the corrosive influence of acidic fluoride-containing toothpaste during orthodontic treatment. Molar bands were placed on 18 orthodontic patients. In these same patients, titanium brackets were bonded on the left quadrants and stainless steel brackets on the right quadrants of the upper and lower arches. Fifteen patients used Gel Kam containing soluble tin fluoride (pH 3.2), whereas 3 used fluoride-free toothpaste. The brackets were removed for evaluation by light microscopy and scanning microscopy 5.5 to 7.0 months and 7.5 to 17 months after bonding. The quality and quantity of elements present were measured by scanning microscopy. Macroscopic evaluation showed the matte gray color of titanium brackets dominating over the silver gleam of the steel brackets. The plaque accumulation on titanium brackets is high because of the very rough surface. Pitting and crevices were observed in only 3 of the 165 brackets tested. The present in vivo investigation confirms the results of in vitro studies, but the changes are so minor that titanium brackets can safely be used for up to 18 months. Wing surfaces should be improved by modifying the manufacturing process.


Assuntos
Braquetes Ortodônticos , Fluoretos de Estanho/química , Titânio/química , Cremes Dentais/química , Adulto , Distribuição de Qui-Quadrado , Criança , Corrosão , Placa Dentária/etiologia , Placa Dentária/prevenção & controle , Humanos , Braquetes Ortodônticos/efeitos adversos , Aço Inoxidável/química , Propriedades de Superfície , Chá/química , Fluoretos de Estanho/uso terapêutico , Titânio/efeitos adversos
19.
Exp Toxicol Pathol ; 53(1): 89-96, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11370740

RESUMO

Stress due to endurance training of striated muscles leads to adaptive changes in the distribution of muscle fiber types (i.e. ratio of type I and type II fibers). Moreover, severe training leads to tissue hypoxia and oxidative stress in muscles. In the current study, we examined the relationship between histological changes and oxidative state in muscles of mastication during the acute adaptation phase to a sustained muscle load. Six domestic pigs received build-ups on the molar teeth in order to induce a sustained load of the muscles of mastication for a duration of four weeks. Afterwards the masseter (M1, M2, M3), medial pterygoid (PM), temporal (TP1, TP2), and geniohyoid muscles (GH) were removed and the fiber type distribution was determined by enzyme histochemistry. Additionally, the tissue content of glutathione and lipid peroxidation (LPO) products were measured. The above treatment led to muscle fiber transformation of type II into type I (M1, M2, TP2, PM) and a decrease of the GSH content (M1, M2 and TP2). The changes in the GSH/GSSG ratio were in accordance with the changes in proportions of muscle fiber types, with the lowest GSH/GSSG ratios in the most stressed muscles of the treated animals. No significant changes in LPO products were found. The decrease of the GSH/GSSG ratio in the most stressed muscles indicates an increased intracellular oxidative stress, which may be caused by tissue hypoxia during the chronic phase of muscle adaptation.


Assuntos
Músculos da Mastigação/metabolismo , Músculos da Mastigação/patologia , Estresse Oxidativo , Condicionamento Físico Animal , Adaptação Fisiológica , Animais , Dissulfeto de Glutationa/metabolismo , Imuno-Histoquímica , Peroxidação de Lipídeos , Fibras Musculares de Contração Rápida/metabolismo , Fibras Musculares de Contração Rápida/patologia , Fibras Musculares de Contração Lenta/metabolismo , Fibras Musculares de Contração Lenta/patologia , Miosinas/análise , Suínos/fisiologia , Suporte de Carga
20.
J Orofac Orthop ; 62(2): 157-62, 2001 Mar.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-11304931

RESUMO

Children who have sustained condylar fractures are treated with functional appliances because surgical repositioning of the condyle is more resource-intensive without producing better results. In cases with additional malocclusions it is practicable to combine the functional therapy of the fracture with skeletal Class II therapy. A 10-year-old boy suffering from a left condylar fracture and showing Class II, Division 2 malocclusion was treated with a skeletal functional appliance in combination with a utility arch for uprighting of the incisors. A modified transpalatal bar was then used to retain the incisor position. The remodeling process of the mandibular condyle following its fracture with dislocation signifies a high adaptability of the affected tissues. This reaction can be used simultaneously for effective sagittal repositioning of the mandible in certain cases of Class II malocclusion.


Assuntos
Traumatismos em Atletas , Má Oclusão Classe II de Angle/complicações , Má Oclusão Classe II de Angle/terapia , Côndilo Mandibular/lesões , Fraturas Mandibulares/complicações , Fraturas Mandibulares/terapia , Procedimentos Cirúrgicos Bucais , Aparelhos Ortodônticos Funcionais , Criança , Seguimentos , Humanos , Masculino , Fatores de Tempo
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