Résumé
El tratamiento endodóntico debe considerar que los dientes presentan una morfología del sistema de canales radiculares con alta variabilidad y complejidad. por lo tanto, el conocimiento acabado de la anatomía radicular y la planificación del procedimiento utilizando sistemas imagenológicos previos a la realización del tratamiento endodóntico, como la tomografía computarizada 3D (CBTC), mejoran el pronóstico, aumentando las probabilidades de éxito. el objetivo de este reporte es mostrar la secuencia de una resolución clínica de un primer premolar inferior (diente 4.4) con una anatomía compleja, utilizando el CBTC tanto en el diagnóstico como en la planificación.
Sujets)
Humains , Femelle , Adulte , Jeune adulte , Prémolaire/imagerie diagnostique , Imagerie tridimensionnelle/méthodes , Cavité pulpaire de la dent/imagerie diagnostique , Racine dentaire/ultrastructure , Racine dentaire/imagerie diagnostique , Prémolaire/ultrastructure , Traitement d'image par ordinateur , Cavité pulpaire de la dent/ultrastructureRésumé
El propósito del trabajo será analizar comparativamente los diversos efectos que producen sobre las restauraciones dentales agentes blanqueadores.El objetivo será valorar los cambios que experimentan en la superficie los materiales de restauración, sometidos a la acción de un agente blanqueador. La metodología utilizada será visualización microscópica electrónica de barrido ambiental. Los resultados obtenidos tendrán transferencia relevante a Insti-tuciones formadoras de recursos humanos en Salud Bucal, al campo profesional odontológico y a empresas o fabricantes para el mejoramiento de su producto...
Sujets)
Amalgame dentaire/analyse , Blanchiment dentaire/effets indésirables , Ciment ionomère au verre/analyse , Peroxyde d'hydrogène/effets indésirables , Résines composites/analyse , Blanchiment dentaire/classification , Prémolaire/ultrastructure , Test de matériaux , Microscopie électronique à balayage/méthodes , Molaire/ultrastructure , Restaurations dentaires permanentes/instrumentation , Propriétés de surface , Dent dévitaliséeRésumé
The purpose of the present study was to evaluate in vivo the failure rate of metallic brackets bonded with two orthodontic composites. Nineteen patients with ages ranging from 10.5 to 38.7 years needing corrective orthodontic treatment were selected for study. The enamel surfaces from second premolars to second premolars were treated with Transbond Plus-Self Etching Primer (3M Unitek). Next, 380 orthodontic brackets were bonded on maxillary and mandibular teeth, as follows: 190 with Transbond XT composite (3M Unitek) (control) and 190 with Transbond Plus Color Change (3M Unitek) (experimental) in contralateral quadrants. The bonded brackets were light cured for 40 s, and initial alignment archwires were inserted. Bond failure rates were recorded over a six-month period. At the end of the evaluation, six bond failures occurred, three for each composite. Kaplan-Meyer method and log-rank test (Mantel-Cox) was used for statistical analysis, and no statistically significant difference was found between the materials (p=0.999). Both Transbond XT and Transbond Plus Color Change composites had low debonding rates over the study period.
O objetivo do presente estudo foi avaliar in vivo a taxa de falha de braquetes metálicos colados com dois compósitos ortodônticos. Dezenove pacientes com idades entre 10,5 e 38,7 anos, que necessitavam de tratamento ortodôntico corretivo, foram selecionados para estudo. As superfícies de esmalte de segundos pré-molares a segundos pré-molares foram tratadas com Transbond Plus Self-Etching Primer (3M Unitek). Em seguida, 380 bráquetes foram colados nos dentes superiores e inferiores, como segue: 190 com compósito Transbond XT (3M Unitek) (controle) e 190 com Transbond Plus Color Change (3M Unitek) (experimental), em quadrantes contralaterais. Os bráquetes colados foram fotopolimerizados por 40 s e arcos de alinhamento inicial foram inseridos. As taxas de insucesso na adesão foram registrados durante um período de seis meses. No final da avaliação, seis falhas de adesão ocorreram, três para cada composto. Para a análise estatística foram utilizados os testes de Kaplan-Meyer e log-rank (Mantel-Cox), e não houve diferença estatisticamente significante entre os materiais (p=0,999). Ambos compósitos, Transbond XT e Transbond Plus Color Change, tiveram baixas taxas de descolagem durante o período de estudo.
Sujets)
Adolescent , Adulte , Enfant , Femelle , Humains , Mâle , Jeune adulte , Résines composites/composition chimique , Collage dentaire , Alliage dentaire/composition chimique , Brackets orthodontiques , Céments résine/composition chimique , Prémolaire/ultrastructure , Lampes à photopolymériser dentaires/classification , Émail dentaire/ultrastructure , Panne d'appareillage , Études de suivi , Photopolymérisation d'adhésifs dentaires/instrumentation , Mandibule , Maxillaire , Fils orthodontiques , Facteurs tempsRésumé
First lower premolars are the teeth with greater variations following third molars. Fifty four first premolars extracted by orthodontic indication from patients in Temuco, Chile, were studied and classified by age, sex and maxillar and mandible location. The following parameters were measured: vestibular-palatine diameter (VP), mesiodistal (MD) diameter, coronary height (C-O), root length and total length. The data were statistically analyzed and tabulated. The results exhibited that first upper premolars showed higher values in the VP diameter and root length compared with the lower, noting significant differences. Further, male sex showed higher values on most measures compared with females, except in root length. Finally a difference in root length was observed between first upper and lower premolars.
Los primeros premolares inferiores son las piezas dentarias con mayores variaciones después de los terceros molares. Se estudiaron 54 primeros premolares extraídos por ortodoncia de pacientes de la ciudad de Temuco, Chile, los cuales fueron clasificados por edad, género y ubicación en los maxilares y en la mandíbula. Se midieron los siguientes parámetros: diámetro vestíbulo-palatino (V-P), mesio-distal (M-D), altura coronaria (C-O), longitud radicular y longitud total. Los datos fueron analizados estadísticamente y tabulados. Los resultados arrojaron que los primeros premolares superiores presentaron valores superiores en el diámetro V-P y la longitud radicular con respecto a los inferiores, observando diferencias estadísticamente significativas. Además, en los hombres se observaron valores superiores en la mayoría de las mediciones, a excepción de la longitud radicular. Finalmente, se observó una diferencia en la longitud radicular entre los primeros premolares maxilares y los mandibulares.
Sujets)
Humains , Mâle , Femelle , Adulte , Prémolaire/anatomie et histologie , Prémolaire/croissance et développement , Prémolaire/embryologie , Prémolaire/ultrastructure , Anthropométrie/méthodesRésumé
This aim of this study was to evaluate the root apex of mandibular premolars regarding the presence of main and accessory foramina. The root apexes from fifty extracted mandibular single-rooted premolars were examined by scanning electron microscopy (SEM). The apical openings had their diameter measured and were identified as main or accessory foramina. Double blinded and calibrated examiners analyzed the SEM photographs and classified the premolar roots into three types, based on the presence and size of the apical openings. Type I: roots with a single main apical foramen and no accessory foramina; type II: roots with a main foramen and one or more accessory foramina; type III: roots with accessory foramina only. For the first premolar, 16 roots were classified as type I (48.48%), 4 as type II (12.12%) and 13 as type III (39.40%). For the second premolars, 10 roots were classified as type I (58.83%), 3 as type II (17.65%) and 4 as type III (23.52%). The high incidence of roots with accessory foramina only (type III), mainly in the first premolar, warns of the need for caution during working length determination and apical debridement.
O objetivo deste estudo foi avaliar o apice radicular de premolares inferiores com relacao a presenca de forames ou foraminas. O apice radicular de cinquenta pre-molares unirradiculados humanos extraidos foram examinados pela microscopia eletronica de varredura (MEV). As aberturas apicais tiveram seus diametros medidos e foram identificados como forames ou foraminas. Dois examinadores calibrados e cegos quanto aos grupos analisaram as micrografias em MEV e classificaram as raizes dos pre-molares em tres tipos, baseadas na presenca e tamanho das aberturas apicais. Tipo I: raizes com um unico forame e nenhuma foramina; tipo II: raizes com um forame e uma ou mais foraminas; Tipo III: raizes somente com foramina. Para o primeiro pre-molar, 16 raizes foram classificadas como Tipo I (48.48%), 4 como tipo II (12.12%) e 13 como tipo III (39.40%). Para o segundo pre-molar, 10 raizes foram classificadas como tipo I (58.83%), 3 como tipo II (17.65%) e 4 como tipo III (23.52%). A alta incidencia de raizes do Tipo III, principalmente no primeiro pre-molar, alerta para a necessidade de cuidados na determinacao do comprimento de trabalho e exploracao foraminal.
Sujets)
Humains , Prémolaire/ultrastructure , Apex de la racine de la dent/ultrastructure , Microscopie électronique à balayage , MandibuleRésumé
OBJECTIVE: The aim of this study was to examine if there are qualitative differences in the appearance of external root resorption patterns of primary teeth undergoing physiologic resorption and permanent teeth undergoing pathological root resorption in different conditions. MATERIAL AND METHODS: A total of 40 teeth undergoing external root resorption in different conditions were divided into 4 groups and prepared for examination under scanning electron microscopy at magnifications ranging from 20x to 1000x. Group I: 10 primary molars exfoliated due to physiologic root resorption; Group II: 10 permanent teeth with periapical granulomas showing signs of resorption; Group III:10 permanent teeth therapeutically extracted during the course of orthodontic therapy with evidence of resorption, and Group IV: 10 permanent teeth associated with odontogenic tumors that showed evidence of resorption. RESULTS: In Group I, the primary teeth undergoing resorption showed smooth extensive and predominantly regular areas reflecting the slow ongoing physiologic process. In Group II, the teeth with periapical granulomas showed the resorption was localized to apex with a funnel shaped appearance in most cases. Teeth in Group III, which had been subjected to a short period of light orthodontic force, showed the presence of numerous resorption craters with adjoining areas of cemental repair in some cases. Teeth associated with odontogenic tumors in Group IV showed many variations in the patterns of resorption with extensive loss of root length and a sharp cut appearance of the root in most cases. CONCLUSION: Differences were observed in the patterns of external root resorption among the studied groups of primary and permanent teeth under physiologic and pathological conditions.
Sujets)
Humains , Microscopie électronique à balayage , Rhizalyse/anatomopathologie , Racine dentaire/ultrastructure , Améloblastome/anatomopathologie , Prémolaire/ultrastructure , Cément dentaire/ultrastructure , Pulpe dentaire/ultrastructure , Dentine/ultrastructure , Incisive/ultrastructure , Molaire/ultrastructure , Orthodontie correctrice , Granulome périapical/anatomopathologie , Tissu périapical/ultrastructure , Apex de la racine de la dent/ultrastructure , Chute dentaire/anatomopathologie , Dent de lait/ultrastructureRésumé
Los implantes oseointegrados forman parte de la práctica clínica en diferentes disciplinas de la rehabilitación funcional y estética del hombre donde el área de la odontología no es una excepción; de esta forma, los implantes dentales son una respuesta a la gran demanda de paciente con edentulismo parcial o total. Existe una importante y creciente investigación en implantología, siendo imperativo reconocer las características histológicas de la reparación ósea cuando son instalados implantes dentarios. El objetivo de esta investigación es reconocer las características histológicas descriptivas de la reparación ósea asociada a la instalación de implantes dentales en dos periodos de evaluación. El modelo experimental utilizado en este estudio correspondió al de cinco perros sometidos a la exodoncia de premolares mandibulares bilaterales. Después de tres meses fueron instalados implantes bilaterales con dos diseños diferentes y con diferentes protocolos de carga. Los sacrificios de los animales fueron realizados después de tres y seis semanas de instalados los implantes. El estudio histológico descriptivo se desarrolló en el tejido adyacente a implantes instalados con técnica sumergida. Se observaron características de reparación ósea en los dos periodos de evaluación. El periodo de tres semanas presento tejido mineralizado en contacto con el implante y tejido conectivo no mineralizado en aumento desde la región superior hacia la inferior. Las regiones de reparación ósea fueron relacionadas con fenómenos de angiogénesis adyacentes. A las seis semanas se observo una mayor formación ósea, reemplazando las áreas de tejido conectivo no mineralizado por tejido mineralizado. Se observo también tejido óseo maduro con canales de Havers bien constituidos. Concluimos que existe una secuencia biológica de reparación ósea respetada en los dos periodos de evaluación, donde después de seis semanas es posible observar un tejido óseo bien constituido, teóricamente ...
Osseointegrated implants are a part of clinical practice in different areas of the aesthetic and functional human rehabilitation where dentistry is not an exception; being like that, dental implants are a responses to great necessity of patient with partial or total dental lost. Exist an important and crescent research in implantology, being very important to recognize the histological characteristic of the osseous repair when dental implant are installed. The aim of this research was to recognize the histological descriptive characteristic of the osseous repair in two evaluation period. The experimental model in this research was five dogs submitted to dental extraction of mandibular bilateral bicuspid. After three month were installed bilateral implants with two implants design and different load protocols. The animals' sacrifices were realized three and six weeks after implants installation. The histological evaluation was realized in a tissue of implant with submerged techniques. Was observed osseous repair characteristic for two evaluation period. For three weeks period was observed mineralized tissue in contact with implant and non mineralized connective tissue in increase from superior to inferior areas. Reparation areas were related to adjacent angiogenic phenomena. For sex weeks period, was observed a major osseous formation, change connective tissue for mineralized tissue. Was observed too matures osseous tissue with well formed Havers channel. We conclude that exist a biological sequence of osseous repair present for a two evaluation period, where in a sex weeks is observed osseous tissue with good definition, theoretically capable for stress support.
Sujets)
Mâle , Animaux , Enfant , Chiens , Prémolaire/anatomie et histologie , Prémolaire/chirurgie , Prémolaire/ultrastructure , Pose d'implant dentaire endo-osseux/méthodes , Pose d'implant dentaire endo-osseux/médecine vétérinaire , Calcification physiologique/physiologie , Modèles animaux , Chiens/anatomie et histologie , Tissu conjonctif/anatomie et histologie , Tissu conjonctifRésumé
The purpose of this study was to evaluate morphological characteristics of teeth with hypercementosis that are relevant to endodontic practice. Twenty-eight extracted teeth with hypercementosis had their root apexes analyzed by scanning electron microscopy (SEM). The teeth were divided according to tooth groups and type of hypercementosis. The following aspects were examined under SEM: the contour and regularity of the root surface; presence of resorption; presence and number of apical foramina, and the diameter of the main foramen. The progression of club shape hypercementosis was directly associated with the presence of foramina and apical foramen obstruction. Cases of focal hypercementosis presented foramina on the surface, even when sidelong located in the root. Circular cementum hyperplasia form was present in 2 out of 3 residual roots, which was the highest proportion among the tooth types. The detection of a large number of foramina in the apical third of teeth with hypercementosis or even the possible existence of apical foramen obliteration contributes to understand the difficulties faced during endodontic treatment of these cases.
Sujets)
Humains , Hypercémentose/anatomopathologie , Apex de la racine de la dent/ultrastructure , Prémolaire/ultrastructure , Canine/ultrastructure , Cément dentaire/ultrastructure , Hyperplasie , Microscopie électronique à balayage , Molaire/ultrastructure , Rhizalyse/anatomopathologie , Racine dentaire/ultrastructureRésumé
Avaliou-se microscopicamente a profundidade de penetraçäo de materiais contendo ionômero de vidro, utilizados como selante em fissuras oclusais (Vidrion C, Fuji IX, Vitremer, Vitro seal alpha), em pré molares superiores hígidos, submetidos a tratamento da superfície oclusal, através de profilaxia coronária com jato abrasivo de bicarbonato de sódio e condicionamento ácido com ácido fosfórico a 37 por cento por 20 segundos. Os resultados mostraram haver diferença significante entre os grupos testados, sendo que o material Vitremer, penetrou mais efetivamente nas fóssulas e fissuras oclusais, quando comparado com o Vidrion C e o Fuji IX
Sujets)
Humains , Adolescent , Enfant , Mâle , Femelle , Prémolaire/composition chimique , Scellants de puits et fissures/analyse , Prémolaire/ultrastructure , Ciment ionomère au verre/analyse , Matériaux dentaires/analyseRésumé
Existe poca información respecto al esmalte aprismático, para hacer una descripción de micromorfología, se utilizaron premolares y molares sanos los que fueron observados con MEB a diferentes aumentos. Se encontró este tipo de esmalte aprismático en fosas, fisuras y en la zona cervical. Se comentan lagunas consideraciones clínicas del grabado ácido del esmalte aprismático o su eliminación previo a restauración de odontología adhesiva
Sujets)
Humains , Prémolaire/ultrastructure , Émail dentaire/ultrastructure , Microscopie électronique à balayage/méthodes , Améloblastes/ultrastructure , Collage dentaire , Émail dentaire/composition chimique , Mordançage à l'acide/méthodes , Molaire/ultrastructureRésumé
En 50 dientes permanentes extraídos por diferentes razones, se demuestra la presencia de esmalte aprismático en un 60 por ciento de los mismos, en las vertientes que configuran fosas y surcos oclusales. En un 22 por ciento guardan relación con las estrías de Retzius de los surcos, en forma imbricada, y en un 78 por ciento, la forma laminar. La metodología empleada: microscopía de polarización y microscopía electrónica de barrido (M.E.B.), permiten determinar su aspecto irregular cuando esta zona es afectada por la caries incipiente. Los procesos de pérdida de sales minerales y remineralización se dan principalmente en esta zona
Sujets)
Humains , Mâle , Femelle , Adolescent , Adulte , Caries dentaires/diagnostic , Caries dentaires/physiopathologie , Émail dentaire/ultrastructure , Fissure dentaire , Prémolaire/ultrastructure , Déminéralisation dentaire/diagnostic , Déminéralisation dentaire/physiopathologie , Microscopie en lumière polarisée/méthodes , Microscopie électronique à balayage/méthodes , Dent de sagesse/ultrastructureRésumé
No presente trabalho, empregando a técnica de microscopia eletrônica de varredura, foram estudadas as características de interface esmalte-selante em dentes pré-molares submetida a técnica invasiva ou näo invasiva. Os dentes tratados foram extraídos (por indicaçäo clínica) e mantidos em soluçäo de alcool a 70 por cento, procedendo-se em seguida fraturas longitudinais no sentido vestibulo-lingual ou tratamento em soluçäo de ácido nítrico a 20 por cento para a obtençäo de amostras. Todas as amostras foram desidratadas em série crescente de álcoois, montadas em bases metálicas para a cobertura de ions de ouro em aparelho "Ions Sputter" e examinadas em microscopio eletrônico de varredura "Stereoscan" 240, Cambridge. De acordo com os resultados obtidos na presente pesquisa podemos concluir que: 1) As peças fraturadas no sentido vestíbulo-lingual e examinadas ao microscópio eletrônico de varredura revelaram nitidamente os detalhes de interface esmalte-selante das diferentes regiöes analisadas. 2) As partículas inorgânicas da matriz do selante Sealite näo interferem na penetrabilidade e no embricamento do selante com a superfície do esmalte. 3) Observou-se a presença de microprojeçöes resinosas "tags" em todas as amostras de selantes preparadas pela técnica invasiva evidenciando um comprimento que variou de 4,239 a 13,953 micrometros. 4) A análise de variância revelou que existe uma diferença estatisticamente significante no comprimento das microprojeçöes do selante quando comparadas as regiöes cavo-superficial, superior, média, inferior e fundo da fissura na técnica invasiva, com maiores valores na regiäo do fundo. 5) A análise de variância revelou que existe uma diferença estatisticamente significante no comprimento das microprojeçöes do selante quando comparadas às regiöes cavo-superficial com superior, média e inferior da fissura e näo significante entre as comparaçöes das regiöes superior, média e inferior na técnica näo invasiva, com maiores valores na regiäo cavo-superficial. 6) Tanto nas técnicas invasiva como nas näo invasiva, apresentaram projeçöes resinosas de formas predominantemente cônicas e de tamanhos variáveis