The impact of occlusal forces on the longevity of restorations

The longevity of dental restorations like fillings, crowns, and bridges is critically influenced by occlusal forces exerted during biting and chewing. These forces vary among individuals based on diet, masticatory habits, and the structural soundness of the dental arch and can range from 11 to over 450 Newtons, depending on circumstances. The choice of restorative material is important for withstanding these forces. While amalgam is durable, modern dentistry has shifted towards aesthetic restoratives such as composite resins and ceramics. However, these materials respond differently to occlusal forces. Ceramics might fracture under excess load, whereas composite resins resist wear but can degrade over time due to other factors. Precision in restoration is crucial to preventing undue occlusal forces that might lead to restoration failure. Tools like T-scan assist in this precision. The manner and distribution of occlusal forces, along with the health of the periodontal ligament, are critical for restoration durability. Bruxism, a parafunctional habit, can significantly impact restorations, necessitating protective measures like occlusal splints and patient education. The interplay of occlusal forces and the chosen restorative material greatly affects the success and lifespan of dental restorations.

Efecto del tratamiento de la morfología oclusal con materiales para restauraciones preventivas / Effect of treating occlusal morphology with materials for preventive restorations

Introducción: las fosas y fisuras son áreas formadas por delgadas irregularidades de la capa del esmalte de la superficie oclusal. La compleja morfología en dientes posteriores es un determinante biológico asociado al desarrollo de caries. Objetivo: evaluar el efecto de diversas formas de tratar la morfología oclusal en la adaptación y penetración de materiales utilizados en restauraciones preventivas. Material y métodos: diseño experimental e in vitro. Sesenta terceros molares fueron distribuidos aleatoriamente en dos grupos: surco sin ameloplastia y con ameloplastia; además, contaban con acondicionamiento del esmalte que se subdividió en tres subgrupos: 1) sellador de fosas y fisuras, 2) adhesivo/sellador de fosas y fisuras y 3) adhesivo/ resina Flow. Resultados: los subgrupos adhesivo/sellador y adhesivo/ Flow alcanzaron mayores valores de adaptación íntima a las paredes del surco. Las diferencias fueron significativas entre los materiales (p = 0.0009). Las mayores zonas de desadaptación resultaron para el sellador sin y con ameloplastia. La penetración de los materiales fue mayor en los surcos con ameloplastia. En los surcos tratados con ameloplastia, el adhesivo/Flow reveló el mayor porcentaje de penetración y la mejor adaptación a las paredes del surco. Conclusiones: la penetración del material está positivamente correlacionada con la profundidad del surco. El sellador con y sin ameloplastia mostró pobre adaptación a las paredes del surco (AU)

Introduction: pits and fissures are areas formed by fine irregularities in the enamel layer of the occlusal surface. The complex morphology in posterior teeth are biological determinants associated with the development of caries. Objective: to evaluate the effect of various ways of treating occlusal morphology on the adaptation and penetration of materials used in preventive restorations. Material and methods: experimental design, in vitro. Sixty third molars were randomly distributed into two groups: groove without ameloplasty and with ameloplasty, with enamel conditioning with three subgroups: 1) pit and fissure sealer, 2) adhesive/pit and fissure sealer, 3) adhesive/resin flow. Results: the adhesive/sealant and adhesive/flow subgroups reached higher values of intimate adaptation to the furrow walls. The differences were significant between the materials (p = 0.0009). The largest areas of maladjustment were found for the sealant without and with ameloplasty. The penetration of the materials was greater in the grooves with ameloplasty. In the grooves treated with ameloplasty, the adhesive/flow revealed the highest percentage of penetration and the best adaptation to the walls of the groove. Conclusions: the penetration of the material is positively correlated with the depth of the furrow. The sealant with and without ameloplasty showed poor adaptation to the sulcus walls (AU)

Fuerza de ruptura y adaptación marginal de carillas oclusales confeccionadas con CAD/CAM composite, cerámica híbrida y feldespática fijadas con distintos medios cementantes / Breaking strength and marginal adaptation of occlusal veneers made with CAD / CAM composite, hybrid ceramic and feldspathic fixed with different cementing medium

Resumen Objetivos: a) Comparar la fuerza de ruptura (FR), adaptación marginal externa (AME) y angulación intracuspídea (AI) entre carillas oclusales confeccionadas con composite, cerámica híbrida y feldespática obtenidas con sistemas CADCAM fijadas con distintos medios cementantes y b) evaluar si el medio cementante, la AME y la AI influyen en la FR. Materiales y métodos: 50 premolares conformaron 6 grupos de acuerdo a la combinación de los materiales Cp, omposite Paradigm MZ100 (P), Cerámica híbrida VitaEnamic (VE), Cerámica feldespática Vitablocks Mark II (F) con los cementos Variolink N curado dual (VN) o resina compuesta Z100 calentada (RC): Grupo 1 (n=10) P-VN, Grupo 2 (n=10) P-RC, Grupo 3 (n=10) VE-RC, Grupo 4 (n=10) VE-VN, Grupo 5 (n=5) F-VN, Grupo 6 (n=5) F-RC. Los dientes preparados y acondicionados recibieron carillas confeccionadas utilizando el Sistema Cerec 3. Luego, fueron sometidas a fuerzas compresivas en una máquina de ensayos universal, aplicando una carga con una velocidad de desplazamiento igual a 0,5 mm/ minuto hasta el cese por fractura catastrófica. Previo a realizar los ensayos se midió la AME en sus cuatro caras y la AI. Resultados: Se obtuvieron valores de mayor FR para los Grupos 1 y 2, que se diferenciaron significativamente de los otros 4 grupos (p<0,05). El medio cementante no influyó sobre la FR (p>0,05). Hubo diferencias con relación a los materiales y la AME favoreciendo al Grupo 1 (p<0,05). Conclusiones: Las carillas oclusales confeccionadas en composite con sistemas CAD-CAM (Paradigm MZ100) necesitaron mayor fuerza para provocar su ruptura y registraron menores desadaptaciones.

Abstract Aims: a)To compare the breaking strength (BS), external marginal adaptation (EMA) and intracuspid angulation (ID) between occlusal veneers made with composite, hybrid ceramic and feldspathic obtained with CAD-CAM systems fixed with different cementing medium and b) to evaluate the effect that the cement, the EMA and ID have on the BS. Materials and methods: 50 premolars formed 6 groups according to the combination of the Composite Paradigm MZ100 (P), VitaEnamic hybrid ceramic (VE), Vitablocks Mark II feldspathic ceramic (F) with the dual-cured Variolink N (VN) or Z100 Heated Composite Resin (RC): Group 1 (n10) P-VN, Group 2 (n10) P-RC, Group 3 (n10) VERC, Group 4 (n10) VE-VN, Group 5 (n5) F-VN, Group 6 (n5) F-RC. The teeth received a preparation and were conditioned, subsequently, they received occlusal veneers using the Cerec 3 System. They were then subjected to compressive forces in a Testing Machine, applying a load with a speed of movement equal to 0.5 mm/ minute until it stopped due to catastrophic fracture. Before carrying out the tests, the EAM was registered in four faces and the ID was measured. Results: Higher BS were obtained for Groups 1 and 2, which differed significantly from Groups 3,4,5 and 6 (p<0.05). The cementing medium did not influence the BS (p>0.05). There were differences in relation to the materials and the EMA favoring Group 1 (p<0.05). Conclusions: The occlusal veneers made in composite with CAD-CAM systems (Paradigm MZ100) required greater force to cause their rupture and registered less misadaptations.

Longevity of bonded composite restorations after dentin biomodification with neolignans obtained from Nectandra leucantha / Longevidade de restaurações de resina composta após biomodificação de dentina com neolignanas obtidas de Nectandra leucantha

Objective: This in vitro study evaluated the effect of neolignan-containing solutions on dentin biomodification previously applied to the bonding procedure in adhesive restorations. Material and Methods: Neolignans, dehydrodieugenol B­CP1 and dehydrodieugenol B methyl ether­CP2, were isolated from Nectandra leucanthaand two aqueous solutions containing 0.13% neolignans, 0.2% propylene glycol and 3.0% ethanol were prepared. Bovine teeth were ground flat to obtain 2-mm thick specimens which received resin composite restorations (N=10). The neolignan solutions were applied before the bonding procedure (60 s). Experimental groups were: control, untreated group, 0.12% chlorhexidine gel, 0.13% CP1 solution, and 0.13% CP2 solution. A push-out bond strength test was conducted (0.5 mm/min). Bovine tooth sections (0.5×1.7×7.0 mm) were also obtained to assess the modulus of elasticity and mass change after treatment (N=15). A three-point bending test evaluated the elastic modulus of fully demineralized dentine beams after immersion in the solutions. The data were statistically analyzed (α = 0.05). Results: The bond strength of the restorations to dentin was significantly improved by the treatment with neolignan-containing solutions, irrespective of the evaluation time (p<0.05). After 6 months, a significant reduction in the bond strength was observed in the groups treated with the solutions (p>0.05), but the means were significantly higher than the control groups (p<0.05). The elastic modulus of demineralized dentin was significantly improved after the treatment with the solutions (p<0.05). All groups lost mass weight. Conclusion: The solutions improved the in vitro longevity of bonded restorations, possibly due to the dentin biomodification effect of the neolignans.(AU)

Objetivo: Este estudo in vitro avaliou o efeito de soluções contendo neolignanas na biomodificação da dentina aplicadas previamente à restaurações adesivas. Material e Métodos: Neolignanas, desidrodieugenol B­CP1 e éter metílico de desidrodieugenol B-CP2, foram isolados da espécie Nectandra leucantha e duas soluções aquosas contendo 0,13% de neolignanos, 0,2% de propilenoglicol e 3,0% de etanol foram preparadas. Dentes bovinos foram lixados para obter espécimes de 2 mm de espessura e preparos cavitários restaurados com resina composta (N=10). As soluções foram aplicadas em dentina antes do procedimento adesivo (60 s). Os grupos experimentais foram: controle, grupo não tratado, gel de clorexidina 0,12%, solução de CP1 a 0,13% e solução de CP2 a 0,13%. Foi realizado o teste de resistência de união push-out (0,5 mm/min). O módulo de elasticidade e a alteração de massa após tratamento da dentina (0,5×1,7×7,0 mm) foram também avaliados em teste de flexão de três pontos (N=15). Os dados foram analisados estatisticamente (α=0,05). Resultados: A resistência de união das restaurações à dentina melhorou significativamente com o tratamento com as soluções, independentemente do tempo de avaliação (p<0,05). Após 6 meses, foi observada redução significativa da resistência de união nos grupos tratados com as soluções (p>0,05), com médias significativamente maiores do que nos grupos controle (p<0,05). O módulo de elasticidade da dentina desmineralizada aumentou significativamente após tratamento com as soluções (p<0,05). Todos os grupos perderam massa, independentemente do tratamento. Conclusão: As soluções melhoraram in vitroa longevidade das restaurações adesivas, possivelmente devido ao efeito biomodificador da dentina das neolignanas(AU)

Transitional Dental implant in Adolescent Patient – A Narrative Review

Aim: This article aims to review the literature available on transitional implants and elaborates on the same through a case report with a follow-up of 5 years. Material and Method: PubMed, Medline, Google Scholar, and Web of Science databases were screened for literature. Articles other than those in English language were excluded. For the review, the complete texts of 49 papers were acquired, with 34 of them being included in the review. Conclusion: Transitional implant placement could be considered as an alternative to removable or fixed resin bonded dental prosthesis in adolescents with a regular follow-up. In such patients, a detailed assessment of growth pattern and a prediction of growth completion has to be done before considering implant as a treatment option.

Percepción de estudiantes respecto al recambio de restauraciones / Students' perception regarding the replacement of restorations

Introducción: El reemplazo de restauraciones defectuosas representa la mayor parte de la práctica del odontólogo, lo que lleva a una perdida mayor del remanente dentario ante cada reemplazo. Objetivo: Determinar si existe variación del criterio clínico en alumnos frente a la decisión de recambio en restauraciones de resina compuesta previo y posterior al reacondicionamiento. Material y Métodos: Estudio analítico transversal. Se contó con una muestra de 40 estudiantes de quinto año de un universo de 72. Se utilizó un set fotográfico, que contaba con restauraciones defectuosas, en uno o más parámetros según los criterios RYGE/USPHS, las cuales posteriormente se reacondicionaron, por lo que se contaba con las fotografías del antes y del después del tratamiento conservador. Se realizó una encuesta a partir de las fotografías mostradas en la cual debían indicar la elección de tratamiento. Resultados: Se observó que hay una gran variación de elección de tratamiento previo a ser reparadas con tratamientos conservadores: 38 por ciento y no conservador de 62 por ciento y frente a la misma restauración de resina posterior a haber sido intervenida la elección de tratamiento conservador fue de 83 por ciento y no conservador 17 por ciento. Mediante el Test de McNemar se obtuvo un p<0.0001 entre elección de tratamiento conservador por sobre el no conservador posterior a haber sido realizada el reacondicionamiento de la restauración. Conclusiones: Existe un cambio en la percepción sobre la indicación de tratamiento de restauraciones defectuosas, a favor de una alternativa conservadora, después de que han sido intervenidas con procedimientos mínimamente invasivos(AU)

Introduction: The replacement of defective restorations, which leads to a greater loss of the dental remnant before each replacement, represents the large majority of the dentist's practice. Objective: To determine if there is any variation in students´ clinical criterion in relation to the decision of replacement of composite resin restorations prior to and following reconditioning. Material and Methods: A cross-sectional analytical study was conducted. The sample was composed of 40 fifth-year students in a universe of 72. A set of photographs showing defective restorations in one or more parameters evaluated according to RYGE / USPHS criteria was used. They were later reconditioned, so there were photographs prior to and following conservative treatment. Based on the photographs shown, a survey in which they had to indicate the choice of treatment was performed. Results: We observed that there is a great variation in the choice of treatment prior to the repair with conservative treatments (38 percent) and non-conservative ones (62 percent), compared to the same resin restoration after the choice of conservative treatment (83 percent) and non-conservative one (17 percent). Using the McNemar Test, p<0.0001 was obtained between the choice of conservative treatment over the non-conservative one after the restoration reconditioning had been performed. Conclusions: There is a change in perception of the indication of treatment to repair defective restorations towards a conservative alternative after they have undergone minimally invasive procedures(AU)

Fracture of upper incisors: a three-year follow-up of a multidisciplinary approach / Fratura em incisivos centrais superiores: tratamento multidisciplinar com acompanhamento clínico de três anos

ABSTRACT Multiple clinical specialties are usually needed for a successful long-term treatment in buccal cavity. The aim of this article is to report a clinical case of multi-disciplinary rehabilitation of fracture upper incisors without pulp exposure, concerning about endodontics, periodontics and restorative dentistry comments or procedures. A case of a patient reporting trauma that resulted in fracture and substantial loss of hard tissue, in mesial angle of both upper central incisors (11 and 21). In palatal side, fracture extended beyond cingulum up to subgingival region. Periodontal surgery was performed in order to reestablish biological space. Clinical and radiographic assessments demonstrated no need for endodontic treatment, since pulp was vital and non-altered. Preparations for restorative procedures were minimally invasive, followed by composite direct. A three-year follow-up was performed, consisting in re-assessment of clinical and radiographic aspects, re-polishing of the restorations and photographic documentation. No pulp tissue alteration was observed after the follow-up period. Restorative procedures, adjacent tissues and pulp vitality were considered adequate, and the patient was satisfied with the treatment.

RESUMO O objetivo deste artigo é relatar um caso clínico de reabilitação de incisivos superiores fraturados sem exposição pulpar, com considerações na área de endodontia, periodontia e dentística restauradora. O caso relata um trauma que resultou em perda substancial de tecido dentário em ângulo mesial de ambos os incisivos centrais superiores. Na parede palatina, a fratura se estendeu além do cíngulo até a região subgengival. A cirurgia periodontal foi realizada para restabelecer o espaço biológico. As avaliações clínicas e radiográficas não demonstraram necessidade de tratamento endodôntico, pois a polpa se apresentava vital e sem alterações. Os procedimentos restauradores foram minimamente invasivos através da realização de restauração direta com resina composta. Foi realizado acompanhamento de três anos, consistindo em reavaliação dos aspectos clínicos e radiográficos, polimento das restaurações e documentação fotográfica. Nenhuma alteração do tecido pulpar foi observada após o período de acompanhamento. Os procedimentos restauradores, tecidos adjacentes e vitalidade pulpar foram considerados adequados e a paciente demonstrou satisfação com o tratamento.

Application and prospects of 3d printing technology in dental manufacturing / 中国组织工程研究

BACKGROUND: In the case of tooth defect or missing, the treatment should be achieved by making a personalized prosthesis. Traditional manufacturing process is time-consuming, costly and accurate. After the introduction of 3D printing technology into dental manufacture, the manufacturing efficiency and quality can be improved to a certain extent. OBJECTIVE: To introduce the application of 3D printing technology in dental manufacture, discuss the bottleneck in recent application, and guide the development of 3D printing technology in dental manufacture. METHODS: The authors used the search times "3D printing, metal implant, dental manufacturing, dental restorations” to search Web of Science, Wanfang, CNKI databases in English and Chinese separately to search papers published during 1980-2019. 261 papers were preliminarily retrieved and 60 of them were included in the final analysis. RESULTS AND CONCLUSION: 3D printing dental mold, digital implant guide plate and wax pattern have been widely used in dental manufacture. 3D printing technology has been widely used in dental manufacture. The most widely used six processes are stereo lithography appearance, laminated object manufacturing, fused deposition modeling, selective laser sintering, selective laser melting, and inkjet printing. There are some technical bottlenecks in the application of 3D printing technology in the field of dental manufacturing. After breaking through technology bottlenecks, 3D printing will be more useful in the field of dental manufacturing in the future.

Assessment of a conservative approach for restoration of extensively destroyed posterior teeth

Abstract Extensive restorations in posterior teeth always bring doubts to the clinicians regarding the best protocol, mainly when structures of reinforcement were lost. Objective This study aimed to evaluate the effect of beveling on the fracture resistance and pattern of class II (MOD) restored teeth. Methodology Ninety human premolars were randomly assigned into 9 groups: CTR (control/sound); NC (cavity preparation, non-restored); RU (restored, unbeveled); RTB (restored, entire angle beveling); RPB (restored, partial/occlusal beveling); EC (endodontic access/EA, non-restored); EU (EA, unbeveled); ETB (EA, entire angle beveling); EPB (EA, partial/occlusal beveling). Teeth were restored with Esthet X resin composite and stored in distilled water for 24 h before the inclusion in PVC cylinders. The axial loading tests were performed with 500 kgF at 0.5 mm/min crosshead speed until fracture of the specimens. Fracture resistance and pattern were accessed and data were analyzed using one-way ANOVA and Tukey's HSD test (α=0.05). Results Mean (±SD) failure loads ranged from 136.56 (11.62) to 174.04 (43.5) kgF in the groups tested without endodontic access. For endodontically accessed teeth, fracture resistance ranged from 95.54 (13.05) to 126.51 (19.88) kgF. Beveling of the cavosurface angle promoted the highest fracture resistance values (p<0.05) and prevented catastrophic fractures. Conclusions Cavosurface angle beveling is capable of improving fracture resistance and pattern for both endodonticaly accessed and non-accessed teeth.

Biological restoration in permanent tooth: four-year follow-up / Restaurações biológicas em dentes permanentes: acompanhamento de 4 anos

Biological restorations, involving a technique of uniting autogenous or homogenous dental fragment for use as the primary restorative material, are an alternative for morphological and functional reestablishment of teeth with extensive coronal destruction. Despite the wide range of restorative materials available in dentistry, no material has proved to be as efficient as the natural tooth structure. This article illustrates a therapeutic option for rehabilitating a devitalized mandibular tooth with a weakened coronal remainder by using the biological restoration technique. The authors present the sequence of planning and performing the technique, such as the characteristics of preparation of the tooth and fragment, impression taking, cutting and cementation of the fragment, and the four-year follow-up of the biological restoration, which shows the success of the technique with marginal adaptation and satisfactory esthetic appearance. (AU)

As restaurações biológicas, envolvendo uma técnica de união de fragmentos dentários autógenos ou homogêneos como principal material restaurador, são uma alternativa para o restabelecimento morfológico e funcional de dentes com destruição coronal extensa. Apesar da ampla gama de materiais restauradores disponíveis na odontologia, nenhum material provou ser tão eficiente quanto a estrutura dentária natural. Este artigo ilustra uma opção terapêutica para reabilitar um molar inferior desvitalizado com um remanescente coronal fragilizado, utilizando a técnica de restauração biológica. Os autores apresentam a sequência de planejamento e execução da técnica, tais como as características de preparação do dente e do fragmento, moldagem, recorte e cimentação do fragmento, e o acompanhamento clínico de 3 anos da restauração biológica, mostrando o sucesso da técnica com uma adaptação marginal e aparência estética satisfatória (AU)

Displasia ectodérmica: relato de caso de reabilitação estético-funcional / Ectodermal dysplasia: case report of aesthetic and functional rehabilitation

Objetivo: Relatar o caso de reabilitação estéticoprotética de um paciente do gênero masculino com 6 anos de idade diagnosticado com Displasia Ectodérmica Hipohidrótica, atendido na clínica de pacientes especiais realizada no projeto de extensão da Universidade Federal Fluminense. Métodos: Trata-se de um estudo observacional, descritivo onde o tratamento restaurador e reabilitador foi realizado e retratado correspondendo às necessidades estéticas e funcionais do paciente. Resultados: Realizou-se reanatomização dos elementos 51 e 61 e confecção de prótese removível para suprir as ausências dos elementos 71, 72, 74, 81 e 82, propiciando função, estética e satisfação relatada pelo paciente. Conclusão: Este relato de caso contribuiu para o aumento de conhecimento acerca das formas de Displasia Ectodérmica, sobre a importância do diagnóstico diferencial das mesmas, bem como para o ensino dos alunos de graduação do projeto de extensão. (AU)

Objective: The aim of this study is to report a case of esthetic and prosthetic rehabilitation of a male 6-yearold patient diagnosed with Hypohidrotic Ectodermal Dysplasia, assisted at the clinicsfor individual withspecial needs held in the extension project of the Federal Fluminense University. Methods: This is a clinical, observational and descriptive study where the restorative and rehabilitative treatment was conducted and reported corresponding to the functional and esthetic needs of the patient. Results: The anatomical shape of teeth 51 and 61 was reconstructed and a partial removable prosthesis was made to cover the absence of teeth 71, 72, 74, 81 and 82, offering function, esthetics and satisfaction, as reported by the patient. Conclusion: This case contributed to increase the knowledge about the types of Ectodermal Dysplasia, the importance of differential diagnosis, as well as teaching of undergraduate students in the extension project. (AU)

Comparación de la microfiltración del Ketac™ Molar e Ionofil Molar® con centrix y espátula TRA / Comparison of the dental leakage between Ketac™ Molar e Ionofil Molar® with centrix and ART spatula

Introducción: El tratamiento restaurador atraumático, es utilizado como parte de los programas preventivos de salud pública, por ello es importante evaluar las técnicas de aplicación del material restaurador utilizando cemento ionómero de vidrio de autocurado. Objetivo: Comparar la microfiltración de los cementos ionoméricos Ketac™ Molar Easy Mix e Ionofil Molar® con dos técnicas de aplicación: jeringa centrix y espátula TRA. Materiales y métodos: Estudio experimental in vitro. Se utilizaron 52 dientes de bovino con preparaciones cavitarias. Las muestras se dividieron en 4 grupos según los cementos ionoméricos y según la técnica de aplicación. Se colocó el material restaurador siguiendo las indicaciones del fabricante. Todas las muestras fueron termocicladas, sumergidas en azul de metileno al 0,05% y seccionadas mediante un corte longitudinal. Se evaluó la microfiltración a través del software del esteromicroscopio. Para comparar las técnicas de aplicación según los cementos ionoméricos se utilizaron las pruebas estadísticas de t de Student y la prueba de U de Mann- Whitney. Resultados: La microfiltración de los cementos ionoméricos Ketac TM Molar Easy Mix e Ionofil Molar® según las técnicas de aplicación jeringa centrix y espátula TRA, no mostraron diferencias estadísticamente significativas (valor p>0,05). El cemento Ketac TM Molar Easy Mix y la técnica con la jeringa centrix y su respectiva combinación fueron los que presentaron menor microfiltración. Conclusión: Todos los dientes presentaron microfiltración y entre ellos el grupo KetacTM Molar Easy Mix® con la jeringa centrix mostraron menores valores de microfiltración

Introduction: Atraumatic restorative treatment is used as part of preventive public health programs, so it is important to evaluate the application techniques of restorative material. Objective: Compare the microleakage of the Ketac ™ Molar Easy Mix and Ionofil Molar® between two application techniques: Centrix syringe and spatula TRA. Materials and methods: Experimental in vitro study. 52 teeth of bovine with cavity preparations were used. The teeth were divided into 4 groups according to ionomer cements, also were subdivided, according to the technique. The restorative material was placed following the manufacturer’s instructions. All teeth were thermocycled, immersed in methylene blue 0.05% and sectioned. It was evaluated with an esteromicroscopio software. To compare the application techniques according the ionomer cements were used statistical tests: Student t test and Mann-Whitney U. Results: The microfiltration of Ketac ™ Molar Easy Mix and Ionofil Molar® ionomeric cements according to centrix syringe and TRA spatula application techniques showed no statistically significant differences (p value > 0.05). The Ketac TM Molar Easy Mix cement and the technique with the centrix syringe were those that presented less microfiltration. Conclusion: All teeth presented microfiltration and among them the group KetacTM Molar Easy Mix® with centrix syringe showed lower values of microfiltration.

Generalidades sobre la mínima intervención en cariología / General remarks about minimal intervention dentistry

Introducción: los tratamientos de la caries dental con mínima intervención incorporan a la ciencia estomatológica: detección, diagnóstico y tratamientos a niveles microscópicos. Objetivo: caracterizar, a través de una revisión bibliográfica, la mínima intervención en el tratamiento de la caries dental. Métodos: se realizó una revisión de la literatura científica sobre mínima intervención en cariología, a través de los buscadores de información y plataformas: SciELO, Hinari, y Medline. Se revisaron 25 revistas de impacto. Se incluyó artículos en idioma inglés y español. Los descriptores empleados para la búsqueda fueron: mínima intervención,odontología/estomatología mínimamente invasiva, cariología, mínima intervención en cariología, tratamiento actual de la caries dental, filosofía mínima intervención, las combinaciones entre ellos y su equivalente en inglés. Se obtuvo 204 artículos; luego de ser filtrados quedaron 32 publicaciones científicas y un libro, que enfocaban esta temática de manera más integral. El 97 por ciento de la bibliografía correspondía a publicaciones realizadas durante los últimos 5 años. Integración de la información: se realiza análisis sobre la prevención, remineralización y tratamientos con técnicas de mínima intervención para la remoción de la caries dental. Conclusiones: la mínima intervención propicia el actuar científicamente de acuerdo a la etapa del proceso caries dental. Es una concepción teórica con herramientas para la práctica encaminada a preservar la mayor cantidad posible de tejido dental de manera que los dientes tengan mayor funcionabilidad(AU)

Introduction: minimal intervention treatments for dental caries enrich dental practice by incorporating detection, diagnosis and microscopic techniques into it. Objective: characterize minimal intervention in the treatment of dental caries by means of a bibliographic review about the subject. Methods: a review was conducted of the literature about minimal intervention in dentistry, using the search engines and platforms SciELO, Hinari and Medline. Twenty-five high impact journals were reviewed. The papers included were in English or Spanish. The descriptors used in the search wereminimal intervention, minimally invasive dentistry, cariology, minimal intervention dentistry, current treatments for dental caries and minimal intervention philosophy, as well as combinations thereof and their counterparts in Spanish. 204 papers were obtained. After being filtered, the sample was composed of 32 scientific journals and one book, i.e. the materials that approached the topic in a more comprehensive manner. 97 percent of the bibliography reviewed had been published in the last five years. Data integration: an analysis was conducted about prevention, remineralization and minimal intervention techniques for the removal of dental caries. Conclusions: Minimal intervention dentistry is characterized by adopting a position in which intervention or preparation of dental tissue is the last choice of therapy resorted to after applying a whole set of prevention and remineralization techniques(AU)

Uso de resina bisacrílica en la resolución estética en adolescente: caso clínico / The use of bisacrylic resin for the esthetic resolution in an adolescent: report of a clinical case

La estética constituye uno de los motivos de consulta de urgencia más frecuentes durante la adolescencia. Recientemente, fueron introducidos en el mercado, productos a base de resinas bisacrílicas. Tienen como componente principal metacrilatos multifuncionales con relleno de vidrio y/o sílice que constituyen la principal diferencia con los acrílicos convencionales. El objetivo de este trabajo es presentar un caso clínico de un paciente de 10 años de edad, resuelto en la Cátedra de Odontología Integral Niños de la Facultad de Odontología, Universidad de Buenos Aires, utilizando para la confección de restauraciones dentales temporales, una resina bisacrílica autopolimerizable.

Aesthetics is one of the most frequent reasons for urgent consultation during adolescence. Recently, products based on bisacrylic resins have been introduced on the market. They have as main component multifunctional methacrylates with filling of glass and / or silica that constitute the main difference with conventional acrylics. The objective of this work is to present a clinical case of a 10-year-old patient, resolved in the Chair of Integral Dentistry of the Faculty of Dentistry, University of Buenos Aires, using for the preparation of temporary dental restorations a bisacrylic resin self-cured.

The effect of improperly contoured and poor fitting restorations to patient with oral lichen planus: periodontal and prosthetic treatment

Oral lichen planus (OLP) is a common mucocutaneous disease, which presents as bilateral or multiple lesions. The several factors are implicated in etiology of OLP such as dental restorations, systemic disease, drugs and stress. Especially the influence of dental restorations and plaque control for OLP has been the interest in dentistry. This case is about OLP patient having poor contoured and ill-fitting metal ceramic restorations. The patient in this study has suffered from OLP for a long time, particularly after restoration of metal ceramic restorations on both posterior teeth of maxilla and mandible. This study reported that OLP lesion recovered effectively by improving the contour and fitness of restorations with plaque control.

Three-year clinical performance of composite restorations placed by undergraduate dental students

This retrospective study evaluated the clinical performance and the reasons for failure of anterior and posterior composite restorations placed by undergraduate dental students over a 3-year period. All cavities were restored using Prime & Bond 2.1 and TPH (Dentsply), according to the manufacturer's indications. One hundred and two patients who had received composite restorations by third and forth year undergraduate students were recalled and examined to analyze the quality of the restorations. The restorations were evaluated using the modified USPHS system. Two hundred and fifty-six composite restorations, 170 in anterior teeth and 86 in posterior teeth, were evaluated. Eighty-five percent of the restorations were considered satisfactory after 3 years. Class II and class IV restorations presented the highest prevalence of failure. Loss of the restoration and deficient marginal adaptation were the main causes of failure. No restoration failed due to secondary caries. Most restorations placed by dental students were considered satisfactory after long-term evaluation. Failure was more prevalent in larger restorations and was not associated with secondary caries.

Este estudo retrospectivo avaliou o comportamento clínico e as razões de falhas de restaurações de resina composta em dentes anteriores e posteriores, realizadas por alunos de graduação em odontologia, após 3 anos de acompanhamento. Cento e dois pacientes que tiveram restaurações de resina composta colocadas por alunos do terceiro ou quarto ano foram rechamados e examinados para analisar a qualidade das restaurações. Todas as cavidades foram restauradas utilizando Prime & Bond 2.1 e TPH (Dentsply), de acordo com as orientações do fabricante. As restaurações foram avaliadas utilizando o sistema USPHS modificado. Duzentas e cinquenta e seis restaurações de resina composta, 170 em dentes anteriores e 86 em posteriores foram avaliadas. Destas restaurações, 85 por cento foram consideradas satisfatórias após 3 anos. Cavidades de classe II e classe IV apresentaram maior prevalência de falhas. Perda de restaurações e adaptação marginal deficiente foram as maiores causas de falhas. Nenhuma restauração falhou em decorrência de cárie secundária. Em conclusão, restaurações de resina composta feitas por estudantes de odontologia foram na sua maioria consideradas satisfatórias após 3 anos. Falhas das restaurações foram mais prevalentes em restaurações maiores e não esteve associada com cárie secundária.

Emprego racional de compósitos com matriz de silorano / Rational use of silorane-based composites

As restaurações diretas de compósitos em dentes posteriores são cada vez mais usadas, devido ao maior interesse pela estética, à abordagem restauradora conservadora e à melhora das propriedades dos materiais. A tensão de contração de polimerização desses materiais pode gerar má integridade marginal, sensibilidade pós-operatória, microinfiltração e manchamento marginal. Visando à redução desses problemas, foi desenvolvido um compósito com um sistema monomérico não baseado em dimetacrilatos: o silorano. O novo compósito tem mostrado boas propriedades mecânicas, estabilidade no meio oral e baixa contração de polimerização. Por ser um novo produto, há carência de estudos clínicos controlados de longo prazo a tal respeito. Assim, o objetivo deste estudo é revisar a literatura e descrever um caso clínico em que se utiliza esse novo material, o Filtek P90 (3M ESPE)

Direct composite restorations in posterior teeth are increasingly used due to the increasing interest on esthetics, conservative approach and the improved properties of latest restorative material. Polymerization shrinkage stresses of such materials are reported to be associated to poor marginal integrity, postoperative sensitivity, microleakage and marginal discoloration. In an attempt to minimize these problems, a new monomer system was developed, which is not based on dimethacrylates: Siloraneo. It has been shown that this novel composite has good mechanical properties, stability in oral environment and low polymerization shrinkage. Because it has been recently introduced, there is a lack of long-term controlled clinical studies about the latter property. The aim of this study was to review the literature and to report a clinical case using a novel material (Filtek P90, 3M ESPE)

Análise do contorno da face proximal obtido em restaurações classe II de resina composta utilizando-se dois tipos diferentes de matrizes metálicas / Proximal contour analysis obtained from class ii in compound resin restorations using two different types of metallic matrices

Introdução: O contorno anatômico proximal em restaurações depende muito do tipo de matriz utilizada. Oobjetivo desse estudo ?in vitro? é analisar o contorno proximal em cavidades do tipo classe II restauradascom resina composta, utilizando-se dois tipos de matrizes metálicas, a convencional (tipo Tofflemire) e a seccionada (Unimatrix). Métodos: Foram selecionados 20 dentes com cavidades mésio-oclusal padronizadascom completa perda do contato proximal. Os dentes foram divididos em dois grupos e restauradosutilizando-se no Grupo 1 a matriz Tofflemire e no Grupo 2, a matriz seccionada Unimatrix. Posteriormente,os dentes foram fotografados e o contorno proximal foi comparado, um a um, com o dente-padrão (hígido). Foram marcados três pontos no dente-padrão que serviram de referência para a medição do contorno. Essa distância foi medida entre os pontos em milímetros para avaliar se o sistema de matriz proporcionou sobrecontorno ou subcontorno. As diferenças foram anotadas em uma planilha eletrônica eos valores submetidos à ANOVA e as diferenças entre os pontos foram analisadas com o teste Newman-Keuls. Resultados: As diferenças entre os pontos foram estatisticamente significantes nos dentes do grupo 1, mas não nos dentes do Grupo 2, mostrando-se que as restaurações dos dentes do Grupo 1 não tiveram um contorno adequado, ao contrário do Grupo 2. Conclusões: As diferenças entre as médias não são ocasionais,mas relacionadas aos sistemas de matriz. O sistema de matriz seccionada proporciona um contorno anatômico mais adequado quando comparado ao sistema de matriz convencional

Introduction: The anatomical proximal contour in dental restorations depends on the type of matrix that is used. The aim of this "in vitro" study is to analyze the proximal contour of Class II in composite resin restored cavities, using two types of metal matrix, the conventional (Tofflemire) and the sectioned one (Unimatrix). Methods: 20 teeth were selected, all of them containing a mesio-occlusal cavity with completeloss of the proximal contact. The teeth were divided into two groups and restored using the Tofflemire matrix in the Group 1 and the sectioned matrix (Unimatrix) in the Group 2. Subsequently, the teeth werephotographed and the proximal contour was compared, one by one, with the pattern tooth (healthy). Three points were marked on the pattern tooth and were used as a reference for measuring the contour. Thisdistance was measured in millimeters between the points to evaluate whether the matrix caused excessivecontour or insufficient one. Differences were recorded in the Excel program and the values were submittedto ANOVA and differences between points were analyzed with the Newman-Keuls test. Results: Differences between points were statistically significant in the teeth of Group 1, but not in the teeth of Group2, showing that the teeth restorations in Group 1 did not present an appropriate contour, and that was nottrue for Group 2. Conclusions: The differences between the means are not occasional, but are related to the matrix systems. The sectional matrix provides better contour when compared to the conventional matrix