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This paper aimed to present a clinical case presenting an unusual periapical radiolucent lesion, its approach and treatment, and as an element of differential diagnosis in periapical pathology. Foreign body granuloma (FBG) is a tissue reaction that is triggered by the deposit of a foreign material affecting the skin and internal organs that the immune system tries to delimit and, if possible, eliminate. FBG may constitute a complication of a surgical procedure or a new pathology for the patient, which precedes an iatrogenic event causing diagnostic difficulties. This study presented an unusual periapical radiolucent lesion in a male patient with a periapical radiolucent area found in panoramic radiography; the lesion was enucleated, histopathologically confirming an FBG, which was the result of a biomaterial used in surgery for nasal polyps and deviated septum performed years before. This case shows us a very unusual presentation of an FBG within the maxillary bone after surgery for nasal polyps and deviated septum. The appropriate use of the available imaging tools and histopathological study and interpretation is emphasized, to be able to carry out a successful long-term treatment with the lowest chances of recurrence. In addition, an interdisciplinary approach is very important, which leads us to the comprehensive treatment of the patient. The proper use of diagnostic and imaging methods that we currently have, as well as knowledge of differential diagnoses, is essential to successfully diagnose and treat injuries in the maxillofacial area. El objetivo de este artículo es exponer un caso clínico con presentación de una lesión radiolúcida periapical inusual, su abordaje y tratamiento, así como su propuesta de elemento de diagnóstico diferencial en patologías periapicales. El granuloma de cuerpo extraño (GCE) es una reacción tisular desencadenada por el depósito de un material extraño que afecta a la piel y a los órganos internos y que el sistema inmunitario trata de delimitar y, si es posible, eliminar. El FBG puede constituir una complicación de una intervención quirúrgica o una patología nueva para el paciente, que precede a un evento iatrogénico causando dificultades de diagnóstico. En este estudio se presenta una lesión radiolúcida periapical inusual en un paciente varón con un área radiolúcida periapical encontrada en la radiografía panorámica; la lesión fue enucleada, confirmando histopatológicamente un FBG, que era el resultado de un biomaterial utilizado en la cirugía de pólipos nasales y tabique desviado realizada años antes. Este caso nos muestra una presentación muy inusual de un FBG dentro del hueso maxilar tras una cirugía de pólipos nasales y desviación de tabique. Se enfatiza el uso adecuado de las herramientas de imagen disponibles y el estudio e interpretación histopatológica, para poder llevar a cabo un tratamiento exitoso a largo plazo con las menores posibilidades de recurrencia. Además, es muy importante el enfoque interdisciplinario, que nos lleva al tratamiento integral del paciente. El uso adecuado de los métodos diagnósticos y de imagen que tenemos en la actualidad, así como el conocimiento de los diagnósticos diferenciales, es fundamental para diagnosticar y tratar con éxito las lesiones en el área maxilofacial.

Introducción: la erosión dental es la pérdida irreversible de estructura dentaria debido a un proceso químico, sin presencia de bacterias, causada por la acción de ácidos que pueden ser de origen extrínseco, intrínseco o ambos. Algunos de los signos de la erosión dental incluyen facetas planas y suaves en las superficies palatinas y vestibulares, así como concavidades superficiales en las caras oclusales. Una causa intrínseca es la presencia de ácido por reflujo gastroesofágico, las causas extrínsecas tienen que ver con la alta ingesta de alimentos ácidos. La enfermedad por reflujo gastroesofágico (ERGE) se ha asociado con problemas dentales como erosión, halitosis, patología de la mucosa y bruxismo. Se pueden encontrar distintos procedimientos para la rehabilitación oral de pacientes con ERGE, entre los cuales se encuentran los procedimientos adhesivos que preservan mayor cantidad de estructura dental sana. Objetivo: realizar el reporte de caso de un paciente con erosión dental causada por ERGE. Presentación del caso: paciente masculino de 32 años de edad que acudió a la clínica de la especialidad de prostodoncia; en el examen intraoral se observaron atriciones por bruxismo y erosiones generalizadas causadas por reflujo gastrointestinal. La restauración de la erosión dental debe basarse en un método conservador y mínimamente invasivo. La técnica de tres pasos que se utilizó para la rehabilitación completa, de acuerdo a la técnica de Francesca Vailati, Urs Cristoph Belser, está estructurada para lograr una rehabilitación adhesiva completa con resultados predecibles y una mínima cantidad de preparación dental. Conclusiones: la terapia restauradora de la erosión dental debe basarse en un método mínimamente invasivo. La enfermedad por reflujo gastroesofágico se ha asociado con problemas dentales como erosión dental, halitosis, patología de la mucosa y bruxismo. Por lo general, los pacientes con ERGE refieren manifestaciones orales de la enfermedad, lo que revela la importancia del tratamiento multidisciplinario y el seguimiento de estos pacientes.

El labio y paladar hendido (LPH) es la malformación craneofacial congénita más frecuente con una incidencia en la población en general de aproximadamente 1:500; en México es de 1:700 nacidos vivos, estos pacientes presentan una mayor incidencia de malformaciones congénitas, las cuales requerirán más de una cirugía reconstructiva como tratamiento, además de un tratamiento interdisciplinario. En éste artículo se presenta el caso de un paciente masculino de 2 años 11 meses de edad con LPH, en el cual se le realizó un tratamiento de operatoria integral que incluyó pulpotomías, restauraciones con coronas de acero, topicación de flúor, selladores y la colocación de una placa obturadora con tornillo transversal, la cual se mantiene con revisiones periódicas. El tratamiento tuvo resultados favorables al ya haber alcanzado una expansión en el maxilar superior, además de recibir una atención multidisciplinaria con lo que se logró mejorar la calidad de vida del paciente.

To present updated information on odontogenic keratocyst (OKC) classification, etiology, genetic and molecular alterations, epidemiology, clinical presentation, radiographic characteristics, histological and immune histochemical features, differential diagnosis, treatment, and controversies, as well as a literature review of case frequencies in different countries.Studies were selected using the key words 'odontogenic keratocyst,' 'odontogenic cysts,' 'odontogenic keratocyst and clinical study'. Full-text papers were reviewed on the basis of the inclusion and exclusion criteria. The literature search aimed to find articles that would show the frequency of OKC, dentigerous cyst, radicular cyst, and other cysts.OKC presents local aggression and high recurrence; therefore, a better understanding of its clinical characteristics and the genetic and molecular factors involved in this peculiar and controversial lesion is required. It is always essential to discuss treatment alternatives. Although OKC is an entity with a high recurrence, aggressive treatment is not advisable in all cases because factors such as commitment to anatomical structures and possible complications should be considered. However, periodic radiographic controls are advised.To reduce the high number of present cases worldwide, it is important to improve knowledge on this pathology so that accurate diagnoses can be achieved and appropriate treatment can be provided. OKC presents local aggression and high recurrence; therefore, a better understanding is needed of the clinical characteristics and genetic and molecular factors involved in OKC. Furthermore, it is always essential to discuss treatment alternatives.

La erupción pasiva alterada (EPA) es una situación clínica común en la que los pacientes muestran un exceso de encía, y generalmente va acompañado de coronas cortas, su tratamiento generalmente involucra el alargamiento de corona que puede ser realizado con el uso de algunos dispositivos que favorezcan una ejecución segura, rápida y eficaz. El propósito de este reporte de caso es presentar el tratamiento estético de paciente con EPA utilizando el Analizador Dento-Facial de Kois (Panadent®) y el Calibrador Estético de Chu (Hu-Friedy®) para realización de alargamientos de corona y restauraciones estéticas con disilicato de litio. Este caso clínico nos muestra que el adecuado diagnóstico y planeación del tratamiento siendo abordadas todas las opciones posibles con el paciente es fundamental para alcanzar resultados longevos y la satisfacción del mismo.

Incomplete polymerisation processes produce several leachable substances. The aim of this work was to review, through existing research and published literature, the genotoxic effect of residual monomers of polymers used in restorative dentistry.The selection of published studies was performed on six databases from January 2000 to June 2020. The keywords used were: 'genotoxicity' or 'DNA damage' and 'dental resin' or 'methacrylates' or 'residual monomers'. The selection was carried out according to the parameters and guidelines of the Preferred Reporting Items for Systematic Review and Metanalyses (PRISMA) and was based on patient, intervention, comparison, and outcome (PICO). The inclusion criteria were: in vitro and in vivo studies published in English that evaluated genotoxicity for residual monomers leached from polymers related to restorative dentistry. Case reports and review articles were excluded.Twenty-seven studies met the eligibility criteria. Two categories were constructed based on the experimental design, in vivo and in vitro reports. For the in vitro research, two main methods of assessing DNA damage were reported in selected studies: micronucleus (MN) counting and alkaline comet assay. For in vivo reports, the main method for assessing genotoxic damage was MN counting.From the electronic search, structured data extraction, and analysis by different independent reviewers, results from the present systematic review allow us to conclude that DNA damage is induced by monomers/co-monomers (triethylene glycol dimethacrylate, bisphenol-A-glycidyl methacrylate, urethane dimethacrylate, and 2-hydroxyethyl methacrylate) that are used in restorative dentistry. This systematic review highlights the need for more research on the use of monomers/co-monomers to properly assess clinical biocompatibility.

To evaluate the biomechanics of endodontically treated incisors restored with a fiberglass post and a CAD/CAM lithium-disilicate ceramic crown with/without a ferrule after thermal and mechanical aging.Twenty bovine incisors were divided into two groups (n = 10): 1. Fe, with a ferrule of 2 mm, and 2. NFe, without a ferrule. After endodontic treatment, the teeth were restored using a fiberglass post (Exacto 3, Angelus) and composite core (Tetric Ceram, Ivoclar Vivadent). They then received a CAD/CAM lithium-disilicate ceramic crown (IPS e.max CAD) luted using a self-adhesive composite (RelyX Unicem 2, 3M Oral Care). All specimens were subjected to 20,000 thermocycles and 2,400,000 simulated chewing cycles. Ceramic crown and root dentin strains (µS) were measured using strain gauges (n = 10) during 100-N loading before and after the thermal and mechanical aging, and upon fracture loading. The specimens were subsequently loaded to fracture (N). The stress distribution was analyzed using 3D individualized finite-element models created by micro-CT of experimental samples (n = 3). Strain data were analyzed using two-way ANOVA and Tukey's HSD test. Fracture resistance was analyzed using Student's t-test and fracture mode was analyzed using the chi-squared test (α = 0.05).After aging, NFe exhibited significantly higher root dentin deformation (buccal: 1248.0 ± 282.8; lingual: 516.2 ± 195.0; p0.001) than Fe (buccal, 554.0 ± 233.8; lingual: 311.8 ± 159.0; p0.001). The deformation measured on ceramic crowns was not influenced by ferrule presence or aging process. Significantly higher fracture resistance (N) was observed for the Fe (1099.6 ± 214.8) than the NFe group (675.3 ± 113.8) (p0.001). The NFe group revealed a lower fracture resistance:root strain ratio than did the Fe group. The stress levels on root dentin and fiberglass were lower for the Fe group.The NFe group showed increased root dentin strain after the aging process. The Fe group revealed higher fracture resistance, lower stress concentration on root dentin and fewer catastrophic fractures.

SUMMARY Objectives This study tested the hypothesis that photoactivation timing and resin cement affect mechanical properties and bond strength of fiberglass posts to root dentin at different depths. Methods Fiberglass posts (Exacto, Angelus) were luted with RelyX Unicem (3M ESPE), Panavia F 2.0 (Kuraray), or RelyX ARC (3M ESPE) using three photoactivation timings: light curing immediately, after three minutes, or after five minutes. Push-out bonding strength, PBS (n=10) was measured on each root region (coronal, middle, apical). The elastic modulus (E) and Vickers hardness (VHN) of the cement layer along the root canal were determined using dynamic indentation (n=5). A strain-gauge test was used to measure post-gel shrinkage of each cement (n=10). Residual shrinkage stress was assessed with finite element analysis. Data were analyzed with two-way analysis of variance in a split-plot arrangement and a Tukey test (α=0.05). Multiple linear regression analysis was used to determine the influence of study factors. Results The five-minute delay photoactivation timing significantly increased the PBS for all resin cements evaluated. The PBS decreased significantly from coronal to apical root canal regions. The mean values for E and VHN increased significantly with the delayed photoactivation for RelyX Unicem and decreased from coronal to apical root regions for all resin cements with the immediate-curing timing. Conclusions The PBS of fiber posts to root dentin, E, and VHN values were affected by the root canal region, photoactivation timing, and resin cement type. Shrinkage stress values decreased gradually with delayed photoactivation for all the cements.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior The restoration of endodontically treated teeth have been a challenge for restorative dentistry because usually the amount of remaining coronal dentin of these teeth are not enough to retain the restorative material, requiring the use of intra-radicular posts to provide retention for the core and restorative crown. This study aimed to evaluate the effect of rehabilitation protocols of endodontically treated teeth for the comparison of in vivo and simultaneous in vitro tests, employing mechanical tests and computational by finite element method; also aims to validate the computational and experimental testing laboratory through comparative analysis with clinical parameters. This study was divided into four specific objectives; specific objective 1: to evaluate the influence of the surface treatments of fiberglass posts on bond strength to root dentin using push-out test; specific objective 2: to develop protocol and validate the generation of three-dimensional patient specific model of anterior central incisors with different ferrule design restored with glass fiber post and CAD- CAM all-ceramic restoration using cone-beam computed tomography and specific software combination for finite elements analysis; specific objective 3: to evaluate the strain before and after thermo-mechanical fatigue aging, the fracture resistance and fracture mode of endodontically treated incisors restored using a fiberglass post and CAD/CAM all ceramic crown with and without ferrule; specific objective 4: generate manuscript that summarize the main findings of specific objective 1, 2 and 3 designated to Brazilian clinical fulfilling the social function of knowledge generation. After analyzing the results it can be concluded that the post surface treatment with 24% hydrogen peroxide for 1 min yielded significantly higher bond strength on the fiberglass posts cementation. The definition of protocol of individualized models provided the sequence necessary for the application of the methodology on patient, the stress distribution on evaluated teeth showed that stresses on left incisor, which had no-uniform ferrule were higher compared with the right incisor, regardless of the loading method. The maintenance of uniform ferrule was more relevant than localized higher ferrule. The ferrule presence prevented the post detaching maintain the root dentin strain after thermal-mechanical aging. The no ferrule group showed increase root dentin strain after aging process. The ferrule group had higher fracture resistance, lower stress concentration on root dentin and 14 less catastrophic fractures. The use of glass fiber post associated to the all ceramic crown allowed the restoration of biomechanics aesthetics and functionality of endodontically treated tooth with periodontal intervention in order to achieve a favorable condition for the restorative procedures. A restauração de dentes tratados endodonticamente têm sido grande desafio para a odontologia restauradora. Geralmente, estes dentes apresentam estrutura coronária insuficiente para reter o material restaurador, sendo necessária a utilização de retentores intrarradiculares para viabilizar a reconstituição coronária. Este trabalho tem como objetivo geral analisar o efeito do protocolo restaurador de dente tratado endodonticamente por meio de avaliação comparativa in vivo e simultânea in vitro, empregando ensaios mecânicos e computacionais pelo método de elementos finitos. Visa ainda validar os ensaios computacionais e ensaios experimentais laboratoriais por meio de análise comparativa com parâmetros clínicos. Este estudo foi dividido em quatro objetivos específicos; objetivo específico 1: avaliar a influência do tratamento de superfície de pinos pré-fabricados na resistência de união de pino ao canal radicular, por meio de teste de micropush-out; objetivo específico 2: desenvolver e validar a geração de modelos tridimensionais específicos de paciente com incisivos centrais anteriores com diferente tamanho de férula, restaurados com pino de fibra de vidro e coroa em cerâmica pura CAD/CAM usando tomografia computadorizada Cone-beam (CT) e combinação de softwares específicos de elementos finitos; objetivo específico 3: avaliar a deformação antes e após ciclagem térmica e mecânica, resistência à fratura e padrão de falha de incisivos tratados endodonticamente restaurados com pino de fibra de vidro e coroa total em cerâmica pura CAD/CAM com e sem férula; objetivo específico 4: gerar síntese dos achados dos objetivos específicos 1, 2 e 3 compilados em um artigo de comunicação aos clínicos brasileiros cumprindo a função social da geração do conhecimento. Após análise dos resultados pode-se concluir que o tratamento de superfície com 24% de peróxido de hidrogênio por 1 minuto resultou em significativamente maior resistência de união na cimentação de pinos de fibra de vidro. A definição do protocolo de modelagem individualizada forneceu as etapas necessárias para a aplicação da metodologia em paciente. A distribuição de tensões mostrou que as tensões geradas no incisivo que não possui férula uniforme, foram maiores em comparação a incisivo com maior extensão de férula independentemente do método de carregamento. A manutenção de férula uniforme foi mais relevante do que maior extensão da férula em uma 11 região específica do preparo. A presença de férula evitou o descolamento do pino de fibra da dentina radicular após fadiga térmica e mecânica. O grupo sem férula apresentou maior deformação radicular após processo de envelhecimento. O grupo com férula apresentou maiores valores de resistência à fratura, baixa concentração de tensões na dentina radicular e menor índice de fraturas catastróficas. O uso de pino de fibra de vidro associado à coroa em cerâmica pura permitiu o restabelecimento da estética e funcionalidade biomecânica do dente tratado endodonticamente com intervenção periodontal voltada aos tecidos de revestimento que possibilitou um recontorno gengival adequado para realização dos procedimentos restauradores. Doutor em Odontologia

We analyzed the effect of the crosshead speed of an applied load on failure load and failure mode of restored human premolars. Fifty intact, noncarious human premolars were selected. Class II mesio-occlusodistal preparations were made with a water-cooled high-speed preparation machine, and the teeth were restored with composite resin. The specimens were divided into five groups (n = 10 each) and tested individually in a mechanical testing machine, in which a 6.0-mm-diameter steel cylinder was mounted to vary the crosshead speed: v0.5: 0.5 mm/min; v1: 1.0 mm/min; v2.5: 2.5 mm/min; v5: 5.0 mm/min; and v10: 10.0 mm/min. The cylinder contacted the facial and lingual ridges beyond the margins of the restorations. Peak load to fracture was measured for each specimen (N). The means were calculated and analyzed with one-way analysis of variance followed by Tukey's test (a = 0.05). The mean load at failure values were (N) as follows: v0.5, 769.4 ± 174.8; v1, 645.2 ± 115.7; v5, 614.3 ± 126.0; v2.5, 609.2 ± 208.1; and v10, 432.5 ± 136.9. The fracture modes were recorded on the basis of the degree of the tooth structural and restorative damage: (I) fracture of the restoration involving a small portion of the tooth; (II) fractures involving the coronal portion of the tooth with cohesive failure of the composite resin; (III) oblique tooth and restoration fracture with periodontal involvement; and (IV) vertical root and coronal fracture. Varying crosshead speeds of 0.5–5.0 mm/min did not influence the failure load of restored maxillary premolars; however, increasing the crosshead speed to 10 mm/min decreased the failure load values and the degree of tooth structural damage.

In this survey, retrospective and prospective clinical studies dealing with cast-post-and core and fiber posts were reviewed regarding the rate of survival of restorations and the most prevalent failures. Electronic searches of the literature were performed in MEDLINE by crossing the key words: "Fiber post and clinical study", "Fiber post and clinical evaluation", "Cast post-and-core and clinical study", and "Root post and retrospective survival study". The cut-off dates were December 1990 through the end of December 2010. Review of literature showed that several interrelated biological, mechanical, and aesthetic factors are involved in the survival rate of restorative procedures in endodontically treated teeth, and post selection should fulfill and optimize these factors. Data based on long-term clinical studies are essential for the general practitioner when making clinical decisions. An adequate selection of teeth and post system must be made, and a minimal amount of existing tooth substance should be removed. A ferrule must be present for safe indication of the fiber posts. Fiber glass posts have demonstrated good survival in clinical studies, with similar performance to cast-post-and cores. Metallic posts have good clinical survival, but the associated failures are mostly irreversible, unlike what happens with the glass fiber posts. O objetivo foi realizar revisão de estudos clínicos retrospectivos e prospectivos de pinos e núcleos metálicos e pinos de fibra em relação à taxa de sobrevivência e tipo de falhas prevalentes. A revisão de literatura foi realizada utilizando a base de dados MEDLINE com os seguintes termos para pesquisa: “Pino de fibra e estudo clínico”, “Pino de fibra e avaliação clínica”, “Pinos e núcleos metálicos e estudo clínico”, “Pinos intra-radiculares e estudo clínicos retrospectivos”. O período avaliado foi de Dezembro de 1990 até o final de Dezembro de 2010. Vários fatores biológicos, mecânicos e estéticos estão envolvidos na taxa de sobrevivência do procedimento restaurador de dentes tratados endodonticamente. A seleção do pino deve satisfazer e otimizar esses fatores. Dados com base em estudos clínicos de longo prazo são essenciais para o clínico geral na tomada de decisões. Adequada indicação na seleção do sistema de pino devem ser feitas. Adicionalmente, desgaste mínimo da estrutura dentária existente deve ser priorizado. A presença de férula deve estar presente para garantir e melhorar a previsibilidade de pinos de fibra. Pinos de fibra de vidro têm demonstrado boa sobrevivência em estudos clínicos, com desempenho semelhante aos pinos metálicos e núcleos moldados e fundidos. Retentores metálicos apresentam boa sobrevivência clínica, no entanto as falhas envolvidas são em sua maioria irreversíveis, ao contrário do que acontece com os pinos de fibra de vidro.

Meneses MS. Influence of resin cement and post configura- tion on bond strength to root dentine. International Endodontic Journal. Aim To evaluate the effect of luting agent and fibreglass post design on bond strength to root dentine at different depths within the canal. Methodology Ninety single-rooted teeth were root filled and prepared to receive either a parallel-sided and serrated fibreglass post (Reforpost no. 2) or a tapered and smooth fibreglass post (Exato Conico). The posts were cemented with the following resin cements: dual- cured resin cement (Rely X ARC), two self-adhesive resin cements (Rely X Unicem and MaxCem) and a self- cured resin cement (Cement-Post). The roots were cross-sectioned to obtain two 1-mm-thick discs for each cervical, middle and apical third of the prepared root portion. The posts were submitted to a micropush-out test at a speed of 0.5 mm min )1 , and the bond strength values (MPa) were submitted to anova in a split-plot arrangement and Tukey's test (P < 0.05). Results The RelyX Unicem demonstrated signifi- cantly higher bond strength values (P < 0.001) along the root dentine. The RelyX ARC and Cement-Post had similar bond strength values in the cervical third; however, the bond strength decreased significantly (P < 0.001) in an apical direction for the RelyX ARC. Significantly lower bond strength values (P < 0.001), irrespective of canal region, were found for MaxCem cement. The bond strength was similar for both post configurations irrespective of the resin cement and canal region. Conclusions The retention of glass fibre posts remained unaffected by surface roughness but was influenced by resin cement type. The self-adhesive cement RelyX Unicem yielded a significantly greater (P < 0.001) bond strength value when cementing the fibreglass posts.

This study evaluated the influence of the surface treatments of fiberglass posts on bond strength to root dentin using push-out test. Forty bovine incisor roots were endodontically treated. The surface of the fiberglass posts (Exacto #2, Angelus) were treated using 4 different protocols (n=10): Control - 70% ethanol for 1 min; 37% phosphoric acid for 1 min; 10% hydrofluoric acid for 1 min; and 24% hydrogen peroxide for 1 min. After a silane coupling agent was applied for 1 min and all posts were cemented using self-adhesive resin cement (RelyX Unicem, 3M-ESPE). The roots were sectioned and two 1-mm-thick slices were obtained from each third: cervical, middle and apical. The specimens were subjected to the push-out test with a crosshead speed of 0.5 mm/min. Data were analyzed by repeated measures ANOVA followed by Tukey's HSD tests (=0.05). The surface treatment (p

SUMMARY Objectives Finite element analysis (FEA) was used to study polymerization shrinkage stress in molars restored with composites and to correlate those stresses with experimentally measured tooth deformation. Methods Three composites (Filtek LS, Aelite LS Posterior, Filtek Supreme) and three filling techniques (bulk, 2.0-mm increments, and 1.0-mm increments) for restoring a molar were simulated in a two-dimensional FEA. Polymerization shrinkage was modeled using post-gel shrinkage, which was measured using the strain gauge technique (n=10). Cuspal tooth deformation, measured at the buccal and lingual surfaces with strain gauges in a laboratory study, was used to validate the analysis. Residual shrinkage stresses were expressed in modified von Mises equivalent stresses. Linear Pearson correlations were determined between the laboratory and FEA results. Results Post-gel shrinkage values (in volume %) were: Filtek LS (0.11 ± 0.03) < Aelite LS Posterior (0.51 ± 0.02) < Filtek Supreme (0.62 ± 0.09). The 1.0-mm increment filling caused substantially higher stresses and strains in the cervical enamel region. Significant correlations were found between: elastic modulus and FEA strain, elastic modulus and FEA stress, post-gel shrinkage and FEA strain, post-gel shrinkage and FEA stress, FEA strain and cuspal deformation by strain gauge, and FEA stress and cuspal deformation by strain gauge (p Conclusions Increasing the number of increments and high post-gel shrinkage and/or elastic modulus values caused higher stresses in the remaining tooth structure and tooth/restoration interface. Cuspal deformation measured with the strain gauge method validated the finite element analyses.

The primary function of the human dentition is preparation and processing of food through a biomechanical process of biting and chewing. This process is based on the transfer of masticatory forces, mediated through the teeth (Versluis & Tantbirojn, 2011). The intraoral environment is a complex biomechanical system. Because of this complexity and limited access, most biomechanical research of the oral environment such as restorative, prosthetic, root canal, orthodontic and implant procedures has been performed in vitro (Assuncao et al., 2009). In the in vitro biomechanical analysis of tooth structures and restorative materials, destructive mechanical tests for determination of fracture resistance and mechanical properties are important means of analyzing tooth behavior. These tests, however, are limited with regard to obtaining information about the internal behavior of the structures studied. Furthermore, biomechanics are not only of interest at the limits of fracture or failure, but biomechanics are also important during normal function, for understanding property-structure relationships, and for tissue response to stress and strain. For a more precise interrogation of oral biomechanical systems, analysis by means of computational techniques is desirable.

Morphology, etching patterns, surface modification, and characterization of 2 different fiber posts: Gfp, Glass fiber post; and Cfp, carbon fiber were investigated by SEM analysis, after different surface treatments. Thirty fiber posts, being 15 Gfp and 15 Cfp were divided into a 5 surface treatments (n = 3): C-alcohol 70% (control); HF 4%-immersion in 4% hydrofluoric acid for 1min; H(3) PO(4) 37%-immersion in 37% phosphoric acid for 30s; H(2) O(2) 10%-immersion in 10% hydrogen peroxide for 20 min; H(2) O(2) 24%-immersion in 24% hydrogen peroxide for 10 min. Morphology, etching patterns, surface modification and surface characterization were acessed by SEM analysis. SEM evaluation revealed that the post surface morphology was modified following all treatment when compared with a control group, for both type of reinforced posts. HF seems to penetrate around the fibers of Gfp and promoted surface alterations. The Cfp surface seems to be inert to treatment with HF 4%. Dissolution of epoxy resin and exposure of the superficial fiber was observed in both post groups, regardless the type of reinforcing fiber, H(2) O(2) in both concentrations. Relative smooth surface area was produced by H(3) PO(4) 37% treatment, but with similar features to untreated group. Surface treatment of fiber post is a determinant factor on micromechanical entanglement to resin composite core. Post treatment with hydrogen peroxide resulted strength of carbon and glass/epoxy resin fiber posts to resin composite core.

La técnica de resinas inyectadas es un tratamiento innovador y poco invasivo ideal para pacientes con erupción pasiva alterada (EPA), cuando la ortodoncia no es una opción. Este tratamiento implica un desgaste mínimo o se puede realizar sin desgaste de tejido dental. Los alargamientos de corona también están indicados en estos casos, para obtener mejores resultados. Este reporte de caso presenta una rehabilitación estética y funcional, utilizando la técnica de resinas inyectadas en el sector antero-superior, en una paciente femenina de 17 años de edad que se presenta a las clínicas odontológicas de la Universidad Autónoma de Guadalajara referida por el departamento de ortodoncia. La paciente presentaba EPA lo cual se corroboró con un estudio periapical completo digital y realizando un sondeo periodontal. La opción de tratamiento ideal en pacientes jóvenes con EPA busca alternativas rehabilitadoras mínimamente invasivas para solucionar problemas estéticos y funcionales, cuando los pacientes no presentan desoclusiones posteriores en movimientos laterales y protrusivos. Esta opción de tratamiento es rápida de realizar y con resultados predecibles para el paciente. La técnica de gingivectomía que complementa la técnica de resinas inyectadas es realizada con electrobisturí y debe ser utilizada en casos específicos, teniendo conocimientos de los principios de la técnica, las habilidades para llevarla a cabo y el manejo adecuado de los tejidos donde se va a aplicar.