Social interaction deficit in children and adolescents with autism : an ethological approach

Orientadores: Paulo Dalgalarrondo, Eleonore Zulnara Freire SetzTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências MédicasResumo: O diagnóstico de crianças com transtornos do espectro autista (TEA) baseia-se na observação e em informações sobre padrões comportamentais e sintomas descritos pelos cuidadores. A etologia é uma área da biologia que pode contribuir significativamente para o desenvolvimento de métodos mais válidos e precisos de mensuração do comportamento de crianças com TEA. Esta pesquisa teve por objetivo desenvolver um etograma novo, detalhado, válido e útil com uma amostra expressiva de crianças e adolescentes com TEA e verificar se este instrumento é capaz de identificar e discriminar os TEA de outro transtorno do desenvolvimento que normalmente é diagnosticado na infância, a deficiência intelectual (DI). Todas as crianças e adolescentes com TEA e DI incluídos neste estudo eram pacientes dos Ambulatórios de Psiquiatria da Criança e do Adolescente do Hospital das Clínicas da Universidade Estadual de Campinas. A amostra foi composta por 69 crianças e adolescentes diagnosticados com TEA entre as idades de três e 18 anos e 77 crianças e adolescentes diagnosticados com DI entre as idades de quatro e 16 anos. O diagnóstico de TEA foi confirmado pela versão brasileira da Childhood Autism Rating Scale (CARS -BR). Todos os participantes com DI apresentaram um QI abaixo de 70, determinado por meio da Escala de Inteligência Wechsler para crianças ou adolescentes, 3ª edição, versão brasileira. Uma câmera escondida de alta definição na forma de uma caneta, com um gravador de vídeo digital, foi utilizada para gravar cada um dos participantes durante as consultas psiquiátricas. Para compor as categorias e subcategorias do etograma, foram selecionadas as dez primeiras gravações de participantes com TEA e DI, totalizando 20 gravações. O etograma foi composto por 10 grandes categorias, divididas em 88 subcategorias, incluindo posturas corporais, verbalizações, estereotipias motoras, posturas de cabeça, comportamento visual, gestos, o estado atual e a distância interpessoal. O teste de Mann-Whitney revelou diferenças significativas entre os participantes com TEA e DI em relação aos sinais clássicos dos TEA e comportamentos que não são típicos dos TEA e da DI, tais como movimentação corporal e exploração do meio. A interação social de crianças e adolescentes com DI foi significativamente melhor do que crianças e adolescentes com TEA, independentemente do seu grau de comprometimento intelectual ou adaptativo. Também foram observadas diferenças significativas entre as categorias de etograma quando os grupos foram divididos por idade, sexo e gravidade. A análise de regressão logística com as categorias e os fatores extraídos da etograma revelou preditores significativos para o diagnóstico dos TEA e dos seus níveis de severidade de acordo com o DSM-IV-TR e DSM-5. O método de observação do comportamento social de crianças e adolescentes baseado na etologia é extremamente eficaz para a identificação dos TEA e para discriminação destes transtornos em relação a DI. É um método barato e minimamente invasivo, que não depende do relato dos pais e do preenchimento de questionários. A etologia pode contribuir significativamente para a investigação dos sinais e sintomas dos TEA, com aplicação importante no contexto clínico do profissional de saúde mental e para fins de pesquisaAbstract: The diagnosis of Autism Spectrum Disorder (ASD) is still based on direct behavior observation or on information about patterns of behaviors and symptoms described by caregivers. Ethology is an area of biology that may contribute significantly to the development of more accurate and valid methods for measuring the behavior of children with ASD. The aims of this study were to develop a new, detailed, valid and useful ethogram with a large sample of children and adolescents with ASD, and to test whether this instrument accurately distinguishes ASD from another developmental disorder that is usually diagnosed in childhood, the Intellectual Developmental Disorder (IDD). All of the children and adolescents with ASD and IDD enrolled in this study were patients of the Child and Adolescent Psychiatry outpatient clinics of the Hospital of the University of Campinas (Unicamp). The participants comprised 69 children and adolescents diagnosed with ASD between the ages of 3 and 18 years; and 77 children and adolescents diagnosed with IDD between the ages of 4 and 16 years. The diagnosis of ASD was confirmed by the Brazilian version of Childhood Autism Rating Scale (CARS-BR). All participants with IDD had a full-scale IQ (FSIQ) below 70, determined using the Wechsler Intelligence Scale for Children or Adults, 3rd edition, Brazilian version. A High-Definition Hidden Camera Pen, with a digital video recorder, was used to record each participant during their regular psychiatric assessment. To compose the categories and subcategories of the ethogram, we selected the first ten recordings from ASD and IDD participants, for a total of 20 recordings. The ethogram comprised 10 major categories divided into 88 subcategories, including body postures, verbalizations, motor stereotypies, head postures, gaze behavior, gestures, current status and interpersonal distance. The Mann-Whitney test revealed significant differences between participants with ASD and IDD in relation to classic signs of ASD and behaviors that are not typical of ASD and IDD, such as body movement and exploitation of the environment. The social interaction of children and adolescents with IDD was significantly better than children and adolescents with ASD, regardless of their degree of intellectual or adaptive impairment. Significant differences between the categories of ethogram were also observed when the groups were divided by age, gender and level of severity. The logistic regression analysis with the categories and the factors extracted from the ethogram showed significant predictors for the diagnosis of ASD and their severity levels according to the DSM-IV-TR and DSM-5. The method of observation and measurement of social behavior of children and adolescents grounded in ethology is extremely effective for the identification of ASD and discrimination of these disorders compared to IDD. It is an inexpensive and minimally invasive method that does not depend on the report of parents and on completing questionnaires. The ethology may contribute significantly to the investigation of the signs and symptoms of ASD, having important application in the clinical context of the mental health professional and for research purposesDoutoradoSaude da Criança e do AdolescenteDoutor em Ciência

Autism and epilepsy: models and mechanisms

Autism is associated with epilepsy in early childhood in almost 30% of children with either disorder, with evidence suggesting the same neurophysiopathology. The common mechanism in both diseases is not well defined and the heterogeneity of clinical symptoms in children with autism spectrum disorder (ASD) and epilepsy highlights the importance of a comprehensive assessment that includes investigation of underlying biological etiologies through neuroimaging, inflammatory, genetic and neurochemistry studies. Here, we review the main aspects of this association between autism and epilepsy.O autismo está associado a epilepsia em aproximadamente 30% dos casos com evidências sugerindo a mesma neurofisiopatologia. O mecanismo comum em ambas doenças ainda não está bem definido e a heterogeneidade dos sintomas clínicos nas crianças com transtorno do espectro autista e epilepsia reforça a importância de uma abordagem que inclui a investigação de etiologias biológicas através de estudos de neuroimagem, dos processos inflamatórios, de genética e neuroquímica. Aqui, iremos revisar os principais aspectos da associação entre autismo e epilepsia.929

Resistência à fratura e padrão de falha de dentes submetidos ao clareamento interno com peróxido de carbamida a 37%, com aplicação de diferentes procedimentos restauradores

OBJECTIVE: This study investigated the compressive fracture strength and failure pattern in premolars submitted to endodontic treatment and internal bleaching with 37% carbamide peroxide for 21 days, with application of different restorative procedures. MATERIAL AND METHODS: Six groups were employed (n = 10): 1) non-bleached teeth and pulp chamber sealed with IRM; 2) bleached teeth and pulp chamber sealed with IRM; 3) bleached teeth and pulp chamber filled with light cured composite resin; 4) bleached teeth, root canals prepared at 10mm, filling of the root canal and pulp chamber with IRM; 5) bleached teeth, root canals prepared at 10mm, luting of prefabricated metallic post with zinc phosphate and pulp chamber sealed with composite resin; 6) bleached teeth, root canals prepared at 10mm, luting of glass fiber post with resin cement and pulp chamber sealed with composite resin. After 24-hour storage in distilled water, the specimens were submitted to compressive fracture strength testing in a universal testing machine. RESULTS: The following values were found: Group 1 - 56.23kgf; Group 2 - 48.96kgf; Group 3 - 53.99kgf; Group 4 - 45.72kgf; Group 5 - 54.22kgf; Group 6 - 60.12kgf. The analysis of variance did not reveal statistically significant difference between groups (pOBJETIVO: O objetivo do estudo foi investigar a resistência à fratura sob compressão e padrão de falha de pré-molares tratados endodonticamente e clareados internamente por 21 dias com peróxido de carbamida a 37%, aplicando-se diferentes procedimentos restauradores. MATERIAL E MÉTODOS: O objetivo deste estudo foi investigar a resistência à fratura sob compressão e padrão de falha de pré-molares unirradiculares tratados endodonticamente e clareados internamente com peróxido de carbamida a 37%. Foram constituídos 6 grupos (n = 10): 1) dentes sem clareamento e câmara pulpar vedada com IRM; 2) dentes clareados e câmara pulpar vedada com IRM; 3) dentes clareados e câmara pulpar preenchida com resina composta fotopolimerizável; 4) dentes clareados, condutos preparados com 10mm, e preenchimento do conduto e câmara pulpar com IRM; 5) dentes clareados, condutos preparados com 10mm, cimentação de pino metálico pré-fabricado com fosfato de zinco e câmara pulpar vedada com resina composta; 6) dentes clareados, condutos preparados com 10mm, cimentação de pino de fibra de vidro com cimento resinoso e câmara pulpar vedada com resina composta. Após 24 horas de armazenamento em água destilada, os espécimes foram submetidos ao teste de resistência à fratura sob compressão em máquina de ensaios universal. RESULTADOS: Os seguintes valores foram encontrados: grupo 1 - 56,23kgf; grupo 2 - 48,96kgf; grupo 3 - 53,99kgf; grupo 4 - 45,72kgf; grupo 5 - 54,22kgf; grupo 6 - 60,12kgf. A Análise de Variância não mostrou diferença estatisticamente significante entre os grupos (p < .05), sugerindo que o clareamento interno com peróxido de carbamida a 37% não enfraqueceu os tecidos dentais. O maior número de fraturas desfavoráveis foi encontrado nos grupos 2 (50%), 4 (40%), e 5 (30%). O grupo 6 exibiu o padrão de falhas mais favorável. CONCLUSÃO: Os resultados sugerem que o clareamento interno com peróxido de carbamida a 37% não causou enfraquecimento importante dos dentes. Entre os dentes clareados, aqueles com restaurações temporárias de IRM ou com pinos metálicos mostraram o padrão mais desfavorável de fratura, enquanto o padrão de fratura mais favorável ocorreu em dentes restaurados com resina composta e pinos de fibras de vidro

Effects of coronal substrates and water storage on the microhardness of a resin cement used for luting ceramic crowns

Composite resin and metallic posts are the materials most employed for reconstruction of teeth presenting partial or total destruction of crowns. Resin-based cements have been widely used for cementation of ceramic crowns. The success of cementation depends on the achievement of adequate cement curing. Objectives: To evaluate the microhardness of Variolink® II (Ivoclar Vivadent, Schaan, Liechtenstein), used for cementing ceramic crowns onto three different coronal substrate preparations (dentin, metal, and composite resin), after 7 days and 3 months of water storage. The evaluation was performed along the cement line in the cervical, medium and occlusal thirds on the buccal and lingual aspects, and on the occlusal surface. Material and Methods: Thirty molars were distributed in three groups (N=10) according to the type of coronal substrate: Group D- the prepared surfaces were kept in dentin; Groups M (metal) and R (resin)- the crowns were sectioned at the level of the cementoenamel junction and restored with metallic cast posts or resin build-up cores, respectively. The crowns were fabricated in ceramic IPS e.max® Press (Ivoclar Vivadent, Schaan, Liechtenstein) and luted with Variolink II. After 7 days of water storage, 5 specimens of each group were sectioned in buccolingual direction for microhardness measurements. The other specimens (N=5) were kept stored in deionized water at 37ºC for three months, followed by sectioning and microhardness measurements. Results: Data were first analyzed by three-way ANOVA that did not reveal significant differences between thirds and occlusal surface (p=0.231). Two-way ANOVA showed significant effect of substrates (

Effects of curing protocol and storage time on the micro-hardness of resin cements used to lute fiber-reinforced resin posts

Objectives: To determine the micro-hardness profile of two dual cure resin cements (RelyX - U100 (R), 3M-ESPE and Panavia F 2.0 (R), Kuraray) used for cementing fiber-reinforced resin posts (Fibrekor (R) - Jeneric Pentron) under three different curing protocols and two water storage times. Material and methods: Sixty 16mm long bovine incisor roots were endodontically treated and prepared for cementation of the Fibrekor posts. The cements were mixed as instructed, dispensed in the canal, the posts were seated and the curing performed as follows: a) no light activation; b) light-activation immediately after seating the post, and; c) light-activation delayed 5 minutes after seating the post. The teeth were stored in water and retrieved for analysis after 7 days and 3 months. The roots were longitudinally sectioned and the microhardness was determined at the cervical, middle and apical regions along the cement line. The data was analyzed by the three-way ANOVA test (curing mode, storage time and thirds) for each cement. The Tukey test was used for the post-hoc analysis. Results: Light-activation resulted in a significant increase in the microhardness. This was more evident for the cervical region and for the Panavia cement. Storage in water for 3 months caused a reduction of the micro-hardness for both cements. The U100 cement showed less variation in the micro-hardness regardless of the curing protocol and storage time. Conclusions: The micro-hardness of the cements was affected by the curing and storage variables and were material-dependent.FAPESP [07/02612-2]CNPq [307510/2010-7]CAPES (Brazil

Influence of the composition and shades of ceramics on light transmission and degree of conversion of dual-cured resin cements

Objective: Since the transmittance of ceramics can influence the degree of conversion (DC) of resin cements, ceramics composition and shade should be considered in the selection of resin cement. This in vitro study aimed to evaluate the effect of the transmittance of different composition, opacities and shades of ceramics on the degree of conversion of two dual-cured resin cements. Methodology: Sixty discs were prepared from low translucency (LT) and medium opacity (MO) lithium disilicate ceramic, and zirconia ceramic (Z). Each group was subdivided into 5 subgroups (n=4) in shades A2, A3.5, B2, C2 and D3. The transmittance measurement was performed in a spectrophotometer. The Variolink II and Rely X U200 resin cements were photoactivated by LED (1400 mW/cm2) for 40 s through the ceramic discs and without the discs (control group). The DC was measured with infrared FTIR spectroscopy, immediately after light activation. Data were analyzed with Kruskall-Wallis and one-way ANOVA, following post-hoc comparisons by Tukey test and Pearson’s correlation test (P&lt;0.05). Results: LT ceramic exhibited higher transmittance values compared to MO and Z ceramics. LTA2 and LTB2 showed statistically higher transmittance values compared to MOA2, MOA3.5 and ZA3.5. For Variolink II, the ceramic interposition did not influence the DC, since there were no statistical differences between groups with ceramic interposition and the control group. For Rely X U200 cement, the interposition of some ceramics types/shades (LTA3.5, MOA2, MOA3.5 and ZA3.5) significantly decreased the DC values compared to control group. A positive correlation was found between the ceramic transmittance and DC values of both tested cements. Conclusions. The transmittance and DC values of the cements were influenced by composition and shades of the ceramics. The higher the transmittance of ceramics, the higher the DC values for both cements

Correlation between margin fit and microleakage in complete crowns cemented with three luting agents

Microleakage can be related to margin misfit. Also, traditional microleakage techniques are time-consuming. This study evaluated the existence of correlation between in vitro margin fit and a new microleakage technique for complete crowns cemented with 3 different luting agents. Thirty human premolars were prepared for full-coverage crowns with a convergence angle of 6 degrees, chamfer margin of 1.2 mm circumferentially, and occlusal reduction of 1.5 mm. Ni-Cr cast crowns were cemented with either zinc phosphate (ZP) (S.S. White), resin-modified glass-ionomer (RMGI) (Rely X Luting Cement) or a resin-based luting agent (RC) (Enforce). Margin fit (seating discrepancy and margin gap) was evaluated according to criteria in the literature under microscope with 0.001 mm accuracy. After thermal cycling, crowns were longitudinally sectioned and microleakage scores at tooth-cement interface were obtained and recorded at &times;100 magnification. Margin fit parameters were compared with the one-way ANOVA test and microleakage scores with Kruskal-Wallis and Dunn's tests (alpha=0.05). Correlation between margin fit and microleakage was analyzed with the Spearman's test (alpha=0.05). Seating discrepancy and marginal gap values ranged from 81.82 &micro;m to 137.22 &micro;m (p=0.117), and from 75.42 &micro;m to 78.49 &micro;m (p=0.940), respectively. Marginal microleakage scores were ZP=3.02, RMGI=0.35 and RC=0.12 (p;0.05). Conclusion: Margin fit parameters and microleakage showed no strong correlations; cast crowns cemented with RMGI and RC had lower microleakage scores than ZP cement

Fracture resistance of weakened roots restored with composite resin and glass fiber post

This study evaluated the fracture resistance of weakened roots restored with glass fiber posts, composite resin cores and complete metal crowns. Thirty maxillary canines were randomly divided into 3 groups of 10 teeth each: teeth without weakened roots (control); teeth with partially weakened roots (PWR) and teeth with and largely weakened roots (LWR). The control group was restored with glass fiber posts and a composite resin core. Teeth in the PWR and LWR groups were flared internally to standardized dimensions in order to simulate root weakness. Thereafter, the roots were partially filled with composite resin and restored in the same way as in the control group. The specimens were exposed to 250,000 cycles in a controlled chewing simulator. All intact specimens were subjected to a static load (N) in a universal testing machine at 45 degrees to the long axis of the tooth until failure. Data were analyzed by one-way ANOVA and Dunnett's test for multiple comparisons (p=0.05). There were statistically significant difference differences (p<0.01) among the groups (control group = 566.73 N; PWR = 409.64 N; and LWR = 410.91 N), with significantly higher fracture strength for the control group. There was no statistically significant difference (p>0.05) between the weakened groups. The results of this study showed that thicker root dentin walls significantly increase the fracture resistance of endodontically treated teeth.Este estudo avaliou a resistência à fratura de raízes fragilizadas restauradas com pinos de fibra de vidro, núcleos de resina composta e coroas totais metálicas. Trinta caninos superiores foram aleatoriamente divididos em 3 grupos. Dentes sem enfraquecimento (grupo controle); grupo de raízes parcialmente enfraquecidas e amplamente enfraquecidas. O grupo controle foi restaurado com pinos de fibra de vidro e núcleo em resina composta. Os dentes dos grupos de raízes parcialmente e amplamente enfraquecidas foram internamente preparadas de maneira padronizada simulando enfraquecimento. Após isto, as raízes foram parcialmente preenchidas com resina composta e restauradas como no grupo controle. Os espécimes foram expostos a 250.000 ciclos em uma máquina de ciclagem mecânica. Todos os dentes intactos foram submetidos à carga estática (N) em uma máquina de ensaio universal a 45 graus ao longo eixo do dente até a sua falha. Os resultados foram analisados através do teste ANOVA a 1 critério e teste de Dunnett para comparações múltiplas (p=0,05). A análise estatística revelou diferenças significantes (p<0,01) entre os três grupos (grupo controle = 566,73 N; RPE = 409,64 N; e ERA = 410,91 N). Quando as três médias de resistência a fratura são ranqueadas as duas menores não se diferem. Os resultados deste estudo mostraram que uma maior espessura de paredes dentinárias aumenta significantemente a resistência à fratura de dentes tratados endodonticamente

Speech in different oral prosthetic rehabilitation modalities for elderly individuals

TEMA: a produção da fala nas modalidades de reabilitação oral protética. OBJETIVO: verificar se o tipo de reabilitação oral interfere na produção da fala. MÉTODO: 36 idosos (média = 68 anos), divididos em 3 grupos, foram avaliados: 13 com dentes naturais (A), 13 com prótese total mucosossuportada superior e inferior (B) e 10 com prótese total mucosossuportada superior e implantossuportada inferior (C). A estabilidade das próteses foi avaliada por um dentista e amostras de fala foram analisadas por 5 fonoaudiólogos. Para determinar a freqüência de alteração dos sons da fala utilizou-se o cálculo da Porcentagem de Consoantes Corretas (PCC). RESULTADOS: observou-se poucos casos com alteração de fala, com maior freqüência no grupo C (23,08%), sendo a articulação travada presente em todos os grupos, a redução dos movimentos labiais em dois grupos (A e B) e a articulação exagerada e a falta de controle salivar em um dos grupos (C e B). Quanto à PCC, menor valor foi observado para os fones linguodentais nos grupos B e C (maior ocorrência de alteração), seguido dos fones alveolares, predominando casos sem alteração no grupo A, contrariamente aos demais grupos, sendo a projeção lingual e o ceceio as alterações mais encontradas. Não houve diferença entre os grupos e a maioria do grupo B estava com a prótese inferior insatisfatória, não havendo associação entre alteração de fala e prótese insatisfatória. CONCLUSÃO: apesar da amostra pequena, indivíduos reabilitados com prótese total apresentam alteração nos fones linguodentais e alveolares e o tipo de prótese, bem como a estabilidade desta parece não interferir na produção da fala.BACKGROUND: speech production in different modalities of oral prosthetic rehabilitation. AIM: to study the speech production of subjects submitted to different oral rehabilitation modalities. METHOD: 36 elderly individuals (average = 68 years) of both gender were evaluated. Participants were divided in three groups: 13 subjects with natural teeth (A); 13 edentate using maxillary and mandibular conventional dentures (B); and 10 edentate using maxillary conventional dentures and mandibular implant-supported prosthesis (C). Prosthesis stability was evaluated by a dentist and speech samples were analyzed by five speech-language pathologists. In order to determine the frequency of speech sound alterations, the Percentage of Correct Consonants (PCC) was used. RESULTS: few individuals presented speech alterations. Group C presented a higher occurrence of speech alterations (23.08%). Locked articulation was present in all groups; the reduction in lip movement was observed for groups A and B; exaggerated articulation and absence of saliva control was observed for group C. A smaller Percentage of Correct Consonants value was observed for the linguodental phonemes, in groups B and C, followed by the alveolar phonemes. Group A presented the majority of individuals with no speech alterations. On the other hand, for groups B and C, lisp and tongue projection was frequently observed. No statistical difference was found between the groups. Most of the individuals in group B presented unsatisfactory prosthesis stability, but no association was identified between speech alterations and prosthesis stability. CONCLUSION: despite the small sample, the results of the study suggest that individuals using dentures present alterations in linguodental and alveolar phonemes. The type of prosthesis and its stability do not seem to interfere in speech production

Evaluation of fracture resistance of endodontically treated teeth restored with prefabricated posts and composites with varying quantities of remaining coronal tooth structure

O objetivo desta pesquisa foi avaliar a influência do remanescente dentário coronal de dentes tratados endodonticamente, restaurados com pinos pré-fabricados e duas resinas como núcleos de preenchimento, uma de presa dual (Enforce Core) e outra fotopolimerizável (Z-250). Foram utilizados 40 caninos superiores humanos extraídos, divididos em quatro grupos de 10 espécimes: Grupo l - com remanescente dentário coronal de 3mm e restaurados com Enforce Core; Grupo ll - com remanescente dentário coronal de 3mm e restaurado com Z-250; Grupo III - sem remanescente dentário coronal e restaurado com Enforce Core; Grupo IV - sem remanescente dentário coronal e restaurado com Z-250. Após restaurados, os dentes foram levados a uma Máquina de Ensaio Universal e submetidos a uma força de compressão à 45º até que ocorresse fratura da restauração. A análise dos resultados (ANOVA, p>;0,05) mostrou não haver diferença estatisticamente significativa entre os dentes com e sem remanescente dentário coronal. Com relação ao material utilizado para o preenchimento coronário, constatou-se diferença significativa, sendo que os valores mais elevados de resistência à fratura foram encontrados no grupo restaurado com a resina fotopolimerizável.OBJECTIVES: The aim of this study was to evaluate the influence of remaining coronal tooth structure on endodontically treated teeth restored with prefabricated posts and two different composites for core build-up: dual-cured resin (Enforce Core) and light-cured resin (Z-250). METHODS: Fourty freshly extracted canines were endodontically treated and divided into four groups: Group I - teeth with 3mm remaining coronal structure, restored with Enforce Core; Group II - teeth with 3mm remaining coronal structure, restored with Z-250; Group III - teeth with no remaining coronal structure, restored with Enforce; Group IV - teeth with no remaining coronal structure, restored with Z-250. After restoration, the teeth were embedded in acrylic resin and the fracture resistance was measured on a universal testing machine at 45 degrees to the long axis of the tooth until failure. RESULTS: Data were analyzed by two-way analysis of variance, which showed significant differences between groups (p=0.00). The Tukey test did not show significant differences between specimens with and without remaining coronal structure. Conversely, significant difference was observed between groups with different core build-up. The highest values of fracture resistance were found in the group restored with light-cured resin. SIGNIFICANCE: The remaining coronal tooth structure did not influence the resistance of endodontically treated teeth; however, the change of core build-up was able to modify this resistence