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Objective: The prevalence of non-carious cervical lesions (NCCLs) has increased in the recent years, especially in the elderly population. The successful prevention and treatment of those lesions requires an understanding of the biomechanics of aged teeth. Considering the importance of such aspect, the impact of the age-related dentin deposition on the stress distribution of NCCLs was evaluated by means of finite element analysis. Material and Methods: A 2-dimensional model of a sound maxillary first premolar was created using CAD software. Two tooth geometries (sound, aged) and two lesion shapes (wedge, saucer) were simulated to the model. The mesh was built with 35,000 triangle and square elements of 0.1 mm in length. All tissues were considered isotropic, homogeneous and linear. Occlusal surfaces were loaded with 300 N for simulating normal chewing forces. The stress distribution was analyzed by a color scale and by the maximum principal stress at the cavosurface line angle. Results: The aged models presented lower stress concentration in the overall system in comparison to sound models. The sharp angle of wedge shaped lesions promoted higher stress concentration at the center of cavosurface angle, favoring the lesions progression. Conclusion: Considering the limitations of the current methodology, it is possible to conclude that aged tooth is a more compact structure that can better respond to stress loadings. This protective intrinsic mechanism should be considered when adopting preventive and restorative measures for NCCLs for the elderly.KeywordsAging; Finite element analysis; Non-carious; Cervical lesions.

Made available in DSpace on 2022-05-01T06:31:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Objective: Evaluate the effect of four preparation designs, two ceramic materials, and two occlusion contact types on the stress distribution of ceramic veneer in upper central incisor. Material and methods: 3D-models were performed in the modeling software containing enamel, dentin, pulp, periodontal ligament and a base of polyurethane resin. The designs were modeled and exported to the computer aided engineering software to perform the static structural analysis. For the mesh, a total of 155429 tetrahedron elements and 271683 nodes were used, after a 10% convergence test. Two materials, lithium disilicate and feldspathic ceramics, were simulated. A static load of 100 N on 45º was applied on the incisal and middle thirds of the palatal tooth region, guided by the occlusal plane. The base was constrained in all directions. The Maximum Principal Stress was the failure criteria chosen for the analysis. Results: The Finite Element Analysis showed that the most conservative designs presented less stress concentration on the ceramic veneer. However, the highest tensile stress concentrations were observed on lithium disilicate veneer with extend design, on the middle third. The type of occlusal contact presented different stress patterns among the preparation designs; the incisal contact showed higher stress concentration compared to middle third contact regardless the ceramic material. Conclusion: To perform a ceramic veneer in upper central incisor, the feldspathic ceramic presented promising results and should be recommended when the extended design was done. Regarding contact types, the incisal contact is more prone to failure regardless the ceramic and preparation design. São Paulo State University (UNESP) Institute of Science and Technology Department of Restorative Dentistry University of Taubaté (UNITAU) Department Dentistry São Paulo State University (UNESP) Institute of Science and Technology Department of Restorative Dentistry

The current outbreak of coronavirus 2019 (COVID-19) challenges how professional standards have been defined so far. In Dentistry, biosafety measures already taken by professionals have been intensified, aiming to offer the patient urgent and emergency treatment with safety for both. In this context, Restorative Dentistry is responsible for the care of patients with caries injuries, with or without symptoms and, fractures of teeth and existing restorations. This article guides professionals, during the pandemic period, on the risks involved in adult and pediatric dental care for patients with restorative needs. It also discusses strategies to optimize clinical practice, reducing risks of contamination and virus transmission.Keywords Operative Dentistry; Dentistry; Biosafety; Pandemics; COVID-19.

Objective: To evaluate the visual perception of surface gloss of resin composite under different illuminants by different observers. Material and methods: twelve cylindrical specimens (6mm x 1mm) were fabricated using a nanofilled resin composite (Z350, A2E shade) in order to compare different observers and to determine the limit of perceptibility of surface gloss. Bovine tooth specimen with similar dimensions was obtained for the comparison of different illuminants. Polishing of resin specimens was performed resulting in 6 groups, presenting surface gloss values at 10, 25, 40, 55, 70, and 85 GU (gloss units), measured by glossmeter (NOVOCURVE). Fifteen individuals were selected: 5 lay-person, 5 undergraduate students, and 5 dental professionals. Participants observed the specimens in a light booth (Gti lightbox) under three different illuminants, and rated the possible combinations between resin specimens or with the bovine enamel specimen (85GU). Data obtained were analyzed by PROBIT non-linear regression analysis (?=0.05). Results: Differences were observed among types of illuminants (p=0.042) and ?GU (p=0.004), with no interaction between factors (p=0.139). The fluorescent light presented lower surface gloss perceptibility values in relation to incandescent light. There was no influence by type of observers (p =0.598). The surface gloss perception limit was 17.6 GU under the presented tested conditions. Conclusion: the illuminant type influenced perception of gloss, with lower percentage of perceptibility for fluorescent light, while such perceptibility was not influence by different observers. Keywords Illuminants; Observer variation; Composite resins; Surface gloss.

Objective: The aim of the study was to evaluate the effect of aging through different thermocycling protocols on the flexural strength of a feldspathic ceramic. Material and Methods: Fifty ceramic bars, Vitablock Mark II (VITA), with dimensions of 18X4X2mm were prepared. The bars were randomly distributed to the groups (n = 10), which were defined according to the number of thermal cycles (TCy): G0 - no TCy; G500 - 500 cycles of TCy; G6000 - 6000 TCy; G10000 - 10000 TCy; G15000 - 15000 TCy. After aging, the specimens were subjected to the three point bending test in a universal testing machine (EMIC DL 1000), under 0.5mm/min speed and loading of 50kgf, until catastrophic failure. A sample of each group was evaluated for topographic morphology under Scanning Electron Microscopy. Results: For mechanical testing, the following mean values and standard deviation (MPa) were obtained: G0 (99.78 ± 5.07); G500 (101.64 ± 5.59); G6000 (98.13 ± 4.95); G10000 (91.77 ± 9.68); G15000 (101.51 ± 4.22). An analysis of variance by regression equation (p = 0.387) was performed, demonstrating a weak and non-significant correlation between flexural strength and number of thermal cycles. Conclusion: It can be concluded that aging in water solely by different numbers of temperature cycles did not influence on the flexural strength of a feldspathic ceramic. Keywords Material resistance; Aging; Ceramics.

Objective: The aim of this study was to assess the amount of chemical elements (Ca, O, C, P, Fe, and Mg) and the cross-section hardness of sclerotic darkened dentin in human teeth. Material and Methods: The study was approved by the local IRB and ten extracted teeth (five sound and five presenting sclerotic darkened dentin) were used. Tooth was sectioned mesiodistally and each half was used for each test. Amount of chemical elements (%w) was determined by energy dispersive X-ray spectroscopy (EDS) in three different dentin areas (shallow, medium, or deep sound or sclerotic dentin). Knoop microhardness was determined at the same EDS areas. Data were analyzed by two-way ANOVA and multiple comparison tests, with significance level at 5%. Results: No difference on microhardness was detected between sound and sclerotic dentin (p = 0.743) and also among dentin depths (p = 0.837). Lower Ca (p = 0.024) and higher C (p = 0.015) amounts were found at superficial sclerotic dentin. Increased Mg content (p < 0.001) was detected in sound dentin. Conclusion: It was concluded darkened sclerotic dentin presents similar cross-section microhardness to sound dentin. The assessed chemical elements were similarly present in sound or sclerotic dentin, except for Mg, which was present higher concentration in sound dentin. Ca and P were lower in superficial sclerotic dentin. Keywords: Dentin; Hardness; Minerals; Tooth Remineralization.

The split-mouth design used in some clinical trials make a randomization scheme on site level where two treatments are randomly assigned to sites of one of the two halves of the mouth. The aim of this review was to summarize guidelines for conducting split-mouth clinical studies in Restorative Dentistry. This is a review performed through scientific articles published between 2004 and 2014 indexed in MEDLINE, PubMed and Scielo databases. The study evaluated USPHS and FDI criteria. The current review showed the main characteristics used in split-mouth studies presented the Restorative Dentistry literature, as ethical aspects, sample calculation, methods of selection and evaluation patients, in order to provide a guideline for clinical conduction. It showed a standard of methodologies to enable comparison among studies. Keywords: Clinical studies, split-mouth design, dentistry.

Objective : This study evaluated the effect of 0.2% chlorhexidine gluconate solution used as an therapeutic primer on the long-term bond strength of etch-and-rinse adhesive to dentin. Material and Methods : Bovine incisors were worn to expose an area of dentin and were divided into 2 groups: Group C (Control) - acid etching with 37% phosphoric acid + Single Bond; Group CHX (0.2% CHX) - acid etching with 37% phosphoric acid + 0.2% CHX for 30 s + Single Bond. Blocks of composite were fabricated and stored for 24 h or 6 months, sectioned into beams and submitted to microtensile tests. Results were analyzed by two-way ANOVA and Tukey tests. Results : Mean (±SD) values (in MPa) were as follow: Group CHX/24h - 41.8(±2.62)A; Group C/24h - 40.8(±3.35)AB; Group CHX/6 months – 36.4(±3.52)B; Group CHX/6 months - 26.1(±1.54)C. Conclusion : CHX improve the imediatte bond strength of resin-dentin and significantly lowered the loss of bond strength after 6 months water storage as seen in the control bonds. Keywords Tensile bond strength; Dentin; Total-etch adhesives; Chlorhexidine gluconate.

Objective - This study evaluated the effect of 0.2% chlorhexidine gluconate solution (CHX), green tea and active epigallocatechin-gallate (EGCG) used as therapeutic primers on the long-term bond strength of etch-and-rinse adhesive to dentin. Material and Methods - Eighty bovine incisors were worn to expose an area of dentin, that were acid-etched (37% phosphoric acid) and rinsed. The teeth were divided into 4 groups (n = 20): Group C (Control) - Single Bond; Group CHX - 0.2% CHX for 30s + Single Bond; Group EGCG - active EGCG gel at 10 µM for 30 s + Single Bond; Group GT - aqueous green tea for 30s + Single Bond. Blocks of composite were fabricated and stored for 24 h or 6 months, sectioned into beams and submitted to microtensile tests. Results were analyzed by two-way ANOVA and Tukey’s test (5%). Results - Mean (±SD) values (in MPa) were as follow: CHX (24 h) – 41.76 (±2.62); C (24 h) - 40.81 (±3.35); GT (24 h): 37.38(2.98); CHX (6 months) - 36.04 (±3.52); EGCG (24h) - 35.91 (±4.82); EGCG (6 months) - 35.75 (±4.44); GT (6 months) - 31.95 (±3.40); C (6 months): 30.05 (±1.54). Conclusion - EGCG produced resin-dentin bonds that did not change after 6 months water storage but it decreased the immediate bond strength when compared to control and chlorhexidine groups.Keywords: Tensile bond strength; Dentin; Total-etch adhesives; Chlorhexidine gluconate; Green tea.

Objective: This study evaluated the effect of thickness on fluorescence of resin composites and tooth substrates (enamel and dentin). Material and methods: Ninety bovine incisors were used, resulting in 45 dentin and 45 enamel disks (6 mm diameter and 0.5, 1 , or 1.5 mm in thickness). Ninety discs of Charisma, Filtek Z350 and IPS Empress Direct (for enamel and dentin) resins at same dimensions were built . Fluorescence measurements were performed using a fluorescence spectrophotometer (RF-5301PC, Shimadzu Corp) with excitation at 365 nm. Data were submitted to 2-way ANOVA and Tukey’s post hoc tests (α = 0.05). Results : The 2 - way - ANOVA revealed statistically significant differences for all factors, as well as the interaction between them (p

Objective: The aim of this study was to evaluate the nine-year clinical performance of Class III composite restorations using two microhybrid anterior composite resins [Magic™-Vigodent/(F) and Z100™-3M ESPE/(Z)]. Material and Methods: The study was a randomized controlled trial, following the split mouth design. Seventy restorations were placed, thirty-five for each resin composite into 35 patients. The restorations were placed by one operator according to the manufacturers’ specifications. Two independent evaluators conducted the clinical evaluation using modified USPHS criteria. After nine-years, 56 restorations (28F-28Z) were evaluated. Data were analyzed using Chi-square, Exact Fisher and McNemar tests (p

Amelogêse imperfeita (AI) é um grupo de desordens hereditárias que afetam primariamente a estrutura do esmalte dentário. Pacientes com AI apresentam estética pobre, sensibilidade dentária excessiva e função mastigtória comprometida. Nestes casos, os tratamentos dentários em idades precoces são frequentemente necessários. Esta revisão descreve as implicações não relacionadas com o esmalte dentário, as estratégias de atuação em idades específicas e ainda os resultados de tratamentos restauradores com determinados materiais e baseados em evidência científica.

Made available in DSpace on 2016-01-28T16:55:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2013. Added 1 bitstream(s) on 2016-01-28T17:02:28Z : No. of bitstreams: 1 ISSN2178-6011-2013-16-01-33-40.pdf: 1634523 bytes, checksum: 8b435701b81a5c49b1a2b042b42e9045 (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Objetivo: Avaliar o comportamento clínico de restaurações de superfícies múltiplas, realizadas com dois cimentos de ionômero de vidro (CIVs) em dentes permanentes, utilizandose o Tratamento Restaurador Atraumático (ART). Material e Métodos: 60 restaurações foram realizadas em escolares (idade entre 9 - 16 anos) por dois dentistas utilizando-se os procedimentos convencionais do AR. As restaurações foram distribuídas aleatoriamente em dois grupos. Trinta cavidades foram restauradas com CIV de alta viscosidade (Ketac Molar - 3M ESPE) e 30, com CIV modificado por resina (Fuji VIII-GC Corp.). Dois avaliadores calibrados e independentes realizaram a avaliação segundo os critérios do ART. Os resultados foram submetidos à análise estatística utilizando-se modelos de regressão logística múltipla, avaliando-se o sucesso em função das variáveis associadas (CIV, operador e tipo de cavidade). Intervalos de confiança de 95% para o sucesso foram baseados na distribuição binomial. Diferenças estatisticamente significantes ocorreram se p < 0,05. Resultados: Em 3 anos de acompanhamento 57 restaurações foram avaliadas. No grupo do Ketac Molar, 3 restaurações não foram avaliadas, 21 obtiveram sucesso e 6 falharam. No grupo do Fuji VIII, 28 restaurações obtiveram sucesso e 2 falharam. A combinação de variáveis foi somente significante em relação à sobrevida das restaurações (p = 0,036). Não houve diferenças entre os grupos considerando-se cada variável independentemente. A combinação apresentando melhor desempenho foi: Fuji VIII, operador B e Classe I envolvendo duas ou mais superfícies dentárias. Conclusão: O desempenho clínico de restaurações de ART de superfícies múltiplas foi considerado satisfatório para ambos os materiais testados, apresentando altos índices de sucesso após três anos. Objective: To evaluate the performance of multiple-surface restorations made with two different glass-ionomer cements (GICs) using the Atraumatic Restorative Treatment (ART) in permanent teeth. Material and methods: A total of 60 restorations were placed in schoolchildren (9-16 years of age) by two dentists using standard ART procedures. The restorations were randomly divided into two groups. Thirty cavities were filled with high-viscosity GIC (Ketac Molar-3M ESPE) and 30 cavities were filled with resin-modified GIC (Fuji VIII-GC Corp.). Two calibrated independent examiners carried out the evaluation according to ART criteria. Data were statistically analyzed using multiple logistic regression models to evaluate the variables associated with the success (GIC, operator, Class type). The 95% confidence intervals (CI) for success were based on the binomial distribution. A difference was statistically significant if p

Most people, when asked about this issue, instantly associate it with fabrication of mouthguards or oral trauma. One cannot deny sports practice might increase the risk of oral trauma, especially the contact sports, and dentists play a key role for prevention and resolution of those problems. However, Sports Dentistry presents field of activity much broader and important. Researches show many athletes have poor oral health, with involvement of dental caries, periodontal problems, and dental erosion. Those conditions lead to reduced quality of life and induce systemic inflammatory response, which possibly affects athletes’ performance during sports practice.