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1.
Orthod Fr ; 91(4): 303-321, 2020 Dec 01.
Artigo em Francês | MEDLINE | ID: mdl-33355535

RESUMO

The aim of this systematic review and meta-analysis was to compare self-ligating brackets (SLBs) considered as a whole to conventional brackets (CBs). An electronic search was performed in three databases (PubMed, MEDLINE via Web of Science, Cochrane Library) from their origin up to June 2017. Additional articles were hand searched from January 2006 to June 2017. This meta-analysis was restricted to randomized controlled trials (RCTs) and split mouth design studies (SMDs). No distinction was made between active and passive SLBs. The following variables were investigated : treatment duration, number of visits, alignment rate, rate of space closure, perception of discomfort during the initial phase of treatment, pain experience during wire insertion or removal, bond failure rate, time to ligate in or to untie an archwire, periodontal indices, occlusal outcomes, transverse arch dimensional changes and root resorption. 25 RCTs and 9 SMDs were finally selected. It was more painful to insert or remove a 0.019× 0.025 SS archwire in/from SLBs. It was significantly quicker to insert or remove an archwire from SLBs. There was less bleeding on probing with SLBs 4 or 5 weeks after bonding. All other variables did not exhibit any significant difference between SLBs and CBs. Out of the 31 comparisons between self-ligating and conventional brackets, 9 only revealed statistically significant differences. This meta-analysis contradicts most of the promotional statements put forward by the distributors.


Assuntos
Braquetes Ortodônticos , Reabsorção da Raiz , Face , Humanos , Boca , Desenho de Aparelho Ortodôntico , Fios Ortodônticos
2.
Eur J Dent Educ ; 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33022873

RESUMO

AIMS: To assess in each European country the correlation between the number of Network of Erasmus-Based European Orthodontic Postgraduate Programmes (NEBEOP) members and orthodontic research activity. Secondary objectives were to describe and quantify Europe's orthodontic research. MATERIALS AND METHODS: Articles published between 2014 and 2018 in 4 major orthodontic journals (American Journal of Orthodontics and Dentofacial Orthopedics, European Journal of Orthodontics, The Angle Orthodontist, Orthodontics and Craniofacial Research) and oral presentation abstracts of five European Orthodontic Society (EOS) congresses were analysed. For each European country, the total number of orthodontic programmes and NEBEOP memberships were collected. Descriptive statistics were performed, and Spearman correlation coefficients and risk ratios were calculated. RESULTS: 2039 articles and 261 oral presentation abstracts were included. Correlation coefficients between national number of publications, oral presentations, sum of these, all adjusted for population, and number of NEBEOP members in each country were 0.64, 0.65 and 0.62, respectively. Risk ratios were all above 1 and statistically significant for number of NEBEOP memberships per country, indicating positive associations with national orthodontic research productivity. Europe accounted for 30.5% of publications and 68.6% of oral presentations at EOS congresses during this period. European orthodontic research was not evenly distributed, since 9 countries were responsible for around 80% of the output. CONCLUSIONS: A positive association was found between number of NEBEOP programmes and national research activity. These results could be an additional argument to support similar pan-European initiatives and guidelines for postgraduate education, not only in orthodontics but in all other dental specialties.

4.
Int Orthod ; 17(4): 817-825, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31481304

RESUMO

This case report shows the orthodontic treatment of four first premolar extractions of a 14-year-old teenager presenting a dental Class I malocclusion with a severe retrognathic mandible. It reflects conflicting views on objectives between the orthodontist who takes into account the facial balance and the patient who only desires a tooth alignment.


Assuntos
Dente Pré-Molar/cirurgia , Má Oclusão de Angle Classe II/terapia , Má Oclusão de Angle Classe I/terapia , Extração Dentária , Técnicas de Movimentação Dentária/métodos , Adolescente , Pontos de Referência Anatômicos , Cefalometria , Modelos Dentários , Mentoplastia , Humanos , Masculino , Má Oclusão de Angle Classe I/diagnóstico por imagem , Má Oclusão de Angle Classe II/diagnóstico por imagem , Aparelhos Ortodônticos Fixos , Fios Ortodônticos , Osteotomia , Técnicas de Movimentação Dentária/instrumentação , Resultado do Tratamento
5.
Eur J Orthod ; 41(5): 447-453, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-30535143

RESUMO

OBJECTIVES: The aim of this retrospective study was to assess in maxillary canine impaction cases both the prevalence of root resorption of adjacent teeth among untreated children and adolescents, and its associated risk factors. SUBJECTS AND METHODS: Sixty subjects (mean age 12.2 years; SD 1.9; range 8-17 years) with 83 displaced maxillary canines and without any past or ongoing orthodontic treatment were included in this study. The presence of root resorption was evaluated on images from a single cone beam computed tomography (CBCT) unit. Potential risk factors were measured on the CBCT images and on panoramic reconstructions of the 3D data sets. The sample was characterized by descriptive statistics and multiple logistic regressions were performed to predict root resorption. RESULTS: Root resorption of at least one adjacent tooth was detected in 67.5 per cent of the affected quadrants. It was found that 55.7 per cent of the lateral incisors, 8.4 per cent of the central incisors, and 19.5 per cent of first premolars were resorbed. Of the detected resorptions, 71.7 per cent were considered slight, 14.9 per cent moderate, and 13.4 per cent severe. Contact between the displaced canine(s) and the adjacent teeth roots was the only identified statistically significant risk factor, all teeth being considered (odds ratio [OR] = 18.7, 95% confidence interval: 2.26-756, P < 0.01). An enlarged canine dental follicle, a peg upper lateral, or an upper lateral agenesis were not significantly associated with root resorption of adjacent teeth, nor were age nor gender. CONCLUSIONS: Root resorption of adjacent teeth was detected in more than two-thirds of a sample of sixty untreated children and adolescents.


Assuntos
Reabsorção da Raiz/etiologia , Dente Impactado/diagnóstico por imagem , Adolescente , Criança , Tomografia Computadorizada de Feixe Cônico , Dente Canino/diagnóstico por imagem , Humanos , Maxila/diagnóstico por imagem , Prevalência , Estudos Retrospectivos , Fatores de Risco
6.
Orthod Fr ; 88(3): 251-261, 2017 09.
Artigo em Francês | MEDLINE | ID: mdl-29043973

RESUMO

INTRODUCTION: The aim of this study is to assess the attractiveness in the smile arch of different vertical positions of the incisal edges of the maxillary lateral incisors. MATERIAL AND METHODS: A frontal photograph of a Caucasian woman's smile was digitally modified to obtain an image with the incisal edges of the maxillary lateral incisors symmetrically tangent to the smile arch. These incisal edges were then moved vertically by 0.5 mm increments. The value was considered positive for an occlusal shift and negative for a gingival shift. Four other images were obtained by moving the incisal edges from +0.5 mm to -1.5 mm. The five images were rated on a visual analog scale by three groups of evaluators: orthodontists, dentists and laypersons. A statistical analysis was performed. RESULTS: Laypersons preferred first lateral incisors tangent to the smile arch, second a +0.5 mm shift, and third a -0.5 mm shift. Orthodontists and dentists preferred first a -0.5 mm shift and second a null shift. CONCLUSIONS: The aesthetic perception of the smile, as regard to the vertical relationships between the incisal edges of the anterior teeth, differs between laypersons and professionals but remains homogenous between orthodontists and dentists. The most consensual aesthetic situation, from both professionals' and laypersons' points of view, is the geometry in which the incisal edges of the maxillary lateral incisors are tangent to the smile arch.


Assuntos
Estética Dentária , Incisivo , Sorriso , Adulto , Idoso , Atitude do Pessoal de Saúde , Odontólogos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ortodontistas , Adulto Jovem
7.
Biomed Mater Eng ; 28(s1): S169-S177, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28372292

RESUMO

Although orthodontics have greatly improved over the years, understanding of its associated biomechanics remains incomplete and is mainly based on two dimensional (2D) mechanical equilibrium and long-time clinical experience. Little experimental information exists in three dimensions (3D) about the forces and moments developed on orthodontic brackets over more than two or three adjacent teeth. We define here a simplified methodology to quantify 3D forces and moments applied on orthodontic brackets fixed on a dental arch and validate our methodology using existing results from the literature by means of simplified hypotheses.


Assuntos
Arco Dental/fisiologia , Análise do Estresse Dentário , Braquetes Ortodônticos , Estresse Mecânico , Dente/fisiologia , Algoritmos , Fenômenos Biomecânicos , Humanos , Desenho de Aparelho Ortodôntico , Fios Ortodônticos
8.
Biomed Mater Eng ; 28(s1): S179-S184, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28372293

RESUMO

Orthodontic appliances deliver forces and moments that will determine movement of teeth. To analyze this latter, we developed an experimental setup to measure the mechanical forces applied on the teeth and to calculate, through a simplified theoretical analysis, the reactive forces and corresponding moments onto the brackets of three adjacent teeth. To validate the theoretical and experimental results, we use a simplified clinical situation of a maxillary canine in infraclusion and surrounded by its corresponding upper lateral incisor and first premolar. Forces are then measured experimentally and compared with the calculated results. From this, we show the specific dissymmetry of the mechanical forces on each side of the maxillary canine due to the applied mechanical forces and the undesirable induced generated moments occurring on each tooth that will directly impact the bone remodeling process and the final tooth repositioning.


Assuntos
Análise do Estresse Dentário , Braquetes Ortodônticos , Estresse Mecânico , Dente/fisiologia , Dente Pré-Molar/anatomia & histologia , Dente Pré-Molar/fisiologia , Fenômenos Biomecânicos , Remodelação Óssea , Simulação por Computador , Análise do Estresse Dentário/métodos , Humanos , Incisivo/anatomia & histologia , Incisivo/fisiologia , Modelos Biológicos , Desenho de Aparelho Ortodôntico , Dente/anatomia & histologia
9.
Orthod Fr ; 85(1): 3-29, 2014 Mar.
Artigo em Francês | MEDLINE | ID: mdl-24685247

RESUMO

Esthetic judgments are surely subjective, but as surely, that does not preclude them being studied objectively through rigorous scientific methods. The factual basis of a science of esthetics is not to settle whether some person or image is "objectively beautiful" but rather to determine whether some representative set or sets of individuals judge or experience him/her/it as beautiful or unattractive. The aim of this paper is to review the definitional, theoretical and methodological aspects pertaining to the perception of facial/dental attractiveness by a group of representative individuals. The first part lays down the basic principles of the perception of facial/dental attractiveness: the perception involves a jury, a field of investigation and a test providing quantitative data; the following general determinants of beauty perception are reviewed: the average morphology, the judge's cultural background, the numerology, the judge's ethnical origin. Indirect determinants are the dentition, the osseous architecture and the muscular envelope. Some disruptive factors might alter the judges' facial perception. They might be qualified as either peripheral to the face or psycho-social factors. Peripheral factors include hair style and color, skin hue, wrinkles, lips color... Psycho-social factors cover the personality of the subject being evaluated, his/her intelligence or behavior. The second part deals specifically with the methodology used to determine facial attractiveness and to correlate this latter with a specific morphology. Typically such a study aims to determine average esthetic preferences for some set of visual displays among a particular jury, given a specific task to judge esthetic quality or qualities. The sample being studied, the displays, the jury or jurys, the rating procedure must all be specified prior to collecting data. A specific emphasis will be given to the rating process and the associated morphometrics, the ultimate goal being to discriminate morphologies judged as attractive among our patients.


Assuntos
Beleza , Estética Dentária , Face/anatomia & histologia , Cefalometria/métodos , Cultura , Ossos Faciais/anatomia & histologia , Músculos Faciais/anatomia & histologia , Humanos , Julgamento , Personalidade , Desejabilidade Social
10.
Orthod Fr ; 84(3): 259-69, 2013 Sep.
Artigo em Francês | MEDLINE | ID: mdl-23993367

RESUMO

INTRODUCTION: Copper-nickel-titanium alloys are supposed to deliver a shape memory effect: when they are brought to a low temperature phase and subjected to a plastic deformation, they should recover their initial shape by simple heating. Nickel-titanium alloys can display different crystallographic phases: martensite, austenite and an inconstant intermediate R-phase. The shape memory effect is generally associated with the transition from martensite to austenite but it could also accompany the transition from R-phase to austenite. Since oral temperatures are not compatible with a fully martensitic alloy, this study aims, for 35° Copper Ni-Ti(®), to assess the R-phase presence at oral temperatures and to verify the possibility of using the R-phase shape memory effect under clinical conditions. MATERIALS AND METHODS: Thirty consecutive 35° Copper Ni-Ti(®) archwires from two different batches were examined by differential scanning calorimetry with partial cycles limited to temperatures encountered within the oral cavity (from 0 °C to 50 °C). The presence of an intermediate crystallographic phase was assessed on the thermograms. The transformation temperatures were determined and the two batches were compared using the Mann-Whitney U Test. RESULTS: Upon heating, all wires transformed directly from martensite to austenite. Af (mean  = 33.5 °C, SD  = 0.8 °C) was generally below the temperature stated by the manufacturer and a statistically significant difference (p ≤ 0.01) was found between the two batches. CONCLUSIONS: No R-phase was detected and transformation temperatures were not constant. This study questions the supposed shape memory effect displayed by 35° Copper Ni-Ti(®) wires under clinical conditions.


Assuntos
Varredura Diferencial de Calorimetria , Cobre , Ligas/química , Teste de Materiais , Fios Ortodônticos
11.
Angle Orthod ; 80(6): 1100-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20677961

RESUMO

OBJECTIVE: To reproduce and compare the intraoral torsional behavior of 10 commonly used preformed upper NiTi 0.017 x 0.025 archwires in 0.018-slot brackets at 20 degrees C, 35 degrees C, and 55 degrees C. MATERIALS AND METHODS: Ten upper preformed NiTi archwires were compared to a multibraided stainless steel wire. An original testing bench was used to reproduce palatal root torque applied onto an upper central incisor with a maximum value of 1540 g x mm. Ten samples of each wire type were tested at 20 degrees C, 35 degrees C, and 55 degrees C each. RESULTS: Loading and unloading at 20 degrees C revealed three categories of wires: a group of four NiTi wires of relative stiffness bereft of any superelasticity, a group of six NiTi wires displaying some horizontal plateau, and finally the stainless steel wire of lesser stiffness. Testing at the average oral temperature of 35 degrees C produced the same three categories of wires, with only 2 of 10 NiTi wires displaying a superelastic effect (Copper NiTi 35 degrees C and 40 degrees C). None of the NiTi wires was superelastic at 55 degrees C. Moments increased with temperature as the martensite was replaced by the more rigid austenite. CONCLUSION: This study showed that most NiTi wires did not exhibit in torsion the superelastic effect traditionally described in bending. The combination of straight-wire prescriptions and rectangular superelastic NiTi archwires did not provide optimal constant moments necessary to gain third-order control of tooth movement early in treatment. A braided stainless steel rectangular archwire displayed better torsional behavior at 35 degrees C than most NiTi archwires of the same dimensions.


Assuntos
Ligas Dentárias , Análise do Estresse Dentário , Fios Ortodônticos , Cobre , Elasticidade , Teste de Materiais , Níquel , Aço Inoxidável , Temperatura , Titânio , Torção Mecânica
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