ABSTRACT
Aim: This study evaluated the effect of a desensitizer agent (DES) during bleaching with 10% carbamide peroxide (CP) on enamel microshear bond strength (µSBS). Methods: Sixty bovine incisors were obtained and randomly distributed into groups (n=15): (C) Control: no desensitizing or bleaching, (DES) desensitizing gel application, (CP) bleaching with 10% CP and (CP/DES) bleaching with 10% CP combined with DES. Bleaching was performed for 6 h/day for 14 consecutive days. DES was applied for 8 h only on the 7th and 14th days of therapy. Specimens were stored in artificial saliva among the CP or DES applications and submitted to µSBS testing at three postrestoration times (n=5): 24 h, 7 days, and 14 days after bleaching using a universal testing machine. Failure modes were observed under a stereomicroscope. Data were analyzed by two-way ANOVA and Tukey's test (α=5%). Results: Immediately after bleaching (24 h), CP promoted lower µSBS than the C and DES groups (p<0.05) but with no differences from the CP/DES. µSBS increased in the DES, CP, and CP/DES groups (p<0.05) when bonding was performed for 7 or 14 days elapsed from bleaching. CP/DES exhibited the highest µSBS among the groups 14 days after bleaching (p<0.05). Cohesive failure in enamel was predominant in the CP groups, while adhesive failure was mostly observed for the other groups. Conclusion: The use of a desensitizer during at-home bleaching maintained the enamel immediate bond strength, and its application favored bonding when the restoration was delayed for 14 days
Subject(s)
Animals , Cattle , Tooth Bleaching , Dental Enamel , Shear StrengthABSTRACT
Realizar o polimento das restaurações diretas em resina composta é importante para estabelecer uma superfície lisa e promover a saúde ao periodonto. O objetivo deste estudo é avaliar a influência de diferentes sistemas de polimento sobre a topografia de superfície de cinco resinas compostas: Master Fill, Vênus, Brilliant, Charisma Opal e Fitek Supreme. Confeccionaram-se 100 corpos de prova com uma matriz metálica cilíndrica de 5mm x 2mm (ISO 4872) distribuídos em cinco grupos teste, de acordo com o tipo polimento (n=20): escova de carbeto de silício (ECS), pasta diamantada (PD), pontas de borracha abrasiva (PB) e discos abrasivos (DA). Os valores de rugosidade (Ra) e as imagens obtidas com a Microscopia de Força Atômica (MFA) foram obtidos antes e após os métodos de polimento. Os resultados foram tabulados e analisados estatisticamente pelo teste de Tukey, com 5% de significância. Conclui-se que os procedimentos de polimento utilizados para as resinas testadas mostraram-se eficazes em reduzir a rugosidade da superfície, com valores variando entre 0,03µm e 0,11µm
Performing the polishing of composite resin direct restorations is important to provide a smooth surface and promote periodontal health. The aim of this study was to evaluate the influence of different polishing systems on surface topography of live composite resins: Master Fill, Venus, Brilliant, Charisma Opal and Filtek Z350. One hundred composite resin specimens were fabricated with a cylindrical metal matrix 5 x 2 mm (ISO 4872) distributed in 5 test groups, according to the type polishing (n:20): SCB silicon carbide brush, DP Diamond paste, TRA tips rubber abrasive and AD abrasive disc. The values of roughness (Ra) and the images taken by Atomic Force Microscopy (AFM) were obtained before and after polishing methods. The results were statistically analyzed by Tukey test at 5% significance level. It was conclude that the polishing procedure used for the resins tested were effective for reducing the surface roughness, with values ranging between 0.03 and 0,011 µm
Subject(s)
Composite Resins , Dental Polishing , Esthetics, DentalABSTRACT
The purpose of this study was to evaluate the dimensional accuracy of different materials used in the confection of dies. Two stainless steel standard models were confected. One of the models, which was 2 mm larger than the other model, was used to provide a uniform relief for the two-step putty-wash impression technique. Thirty impressions were obtained using a polyvinyl siloxane impression material and randomly divided into three groups (n = 10) according to the type of casting material: type IV dental stone, commercially available epoxy resin (Tri-Epoxy), and industrial epoxy resin (Sikadur). After the setting/polymerization of the casting material, the dimensional stability was measured in terms of the height, diameter of the base and diameter of the top from the obtained dies and from the standard metal model using a profile projector. Results were analyzed by ANOVA and Dunnet test (α = 0.05). In the height values, no significant difference was observed between the groups, except for Sikadur casts, which showed lower mean values. The Tri-Epoxi group showed statistically lower mean base diameter values, compared with the other groups, and both epoxy resin groups showed statistically lower mean top diameter values, compared with that for the type IV dental stone group. We concluded that type IV gypsum and the commercially available epoxy resin showed similar behavior in most areas. The industrial epoxy resin did not show the same characteristics, although the diameter of the base obtained with it was similar to that obtained with type IV dental stone.
ABSTRACT
O crescente interesse dos pacientes por restaurações estéticas proporciona o surgimento de novos materiais e técnicas restauradoras. A associação de diferentes materiais dentários requer planejamento reabilitador minucioso, para se obter prognóstico favorável ao tratamento. Este trabalho relata um caso clínico de reabilitação bucal com próteses fixas, demonstra todas as etapas clínicas do tratamento e enfatiza o planejamento, os preparos cavitários, a confecção das próteses provisórias, os procedimentos de moldagem, a prova das infraestruturas, o ajuste estético das cerâmicas e a cimentação final. Conclui-se que a reabilitação devolveu ao paciente função mastigatória e estética...
The increasing interest of the patient for esthetic restorative procedures led to the introduction of novel materials and techniques. The association of different types of dental materials demands a comprehensive rehabilitation planning to achieve a favorable prognostic. The aim of this work was to report a case of extensive oral rehabilitation with fixed prosthesis showing the step-by-step treatment, emphasizing treatment planning, preparation, provisionalization, impression taking, clinical adjustments of copings and veneering material, and final luting. It can be concluded that the resulting rehabilitation provided the patient´s masticatory and esthetic function...
Subject(s)
Humans , Male , Adult , Dental Porcelain , Dental Prosthesis , Denture Design , Esthetics, Dental , Mouth RehabilitationABSTRACT
As lesões oclusais denominadas cáries ocultas têm sido muito observadas na prática clínica nos últimos anos, e são evidenciadas com auxílio de radiografia interproximal. Essas lesões acometem pequena parte da superfície do esmalte oclusal e progridem rapidamente pela dentina. Restabelecer a estética, a função e anatomia dos dentes posteriores tem sido, cada vez mais, grande desafio para o clínico, em função da maior exigência dos pacientes. A técnica restauradora com resinas compostas e auxílio da matriz oclusal possibilita a reconstrução da estrutura anatômica dental com previsibilidade e segurança. Este trabalho demonstra, com um relato de caso clínico, a técnica restauradora com resina composta e matriz oclusal em um primeiro molar inferior, acometido por lesão de cárie oculta...
Hidden caries have been commonly observed in dental practice in the last years, and their presence can be confirmed by bitewing radiographs. These lesions initiate in enamel subsurface and advance quickly to dentin. The reestablishment of esthetics, function and anatomy of posterior teeth is a significant challenge for the professional, due to the high demand by the patient. Restorative techniques using composite resins and an occlusal matrix make possible the reconstruction of the dental anatomy. The aim of this case report is to demonstrate a restorative technique using composite resin and an occlusal matrix in a first mandibular molar presenting hidden caries lesion...
Subject(s)
Humans , Female , Adolescent , Composite Resins , Dental Caries , Dentition, Permanent , Esthetics, DentalABSTRACT
O aumento na expectativa de vida da população e a preocupação com a qualidade de vida têm motivado os pacientes com edentulismo total a buscar os consultórios odontológicos para realizar tratamento reabilitador. Este trabalho relata um caso clínico de prótese total superior e inferior, com o objetivo de demonstrar os aspectos clínicos da confecção das próteses desde o exame clínico, procedimentos de moldagem, determinação da dimensão vertical de oclusão e estética dos dentes e da gengiva
Increasing life expectancy of population and awareness with life quality led edentulous patients to seek for rehabilitation treatment in dental practice. This article is a case report of complete dentures, showing clinical aspects such as initial clinical examination, impression-taking procedures, proper occlusal height dimension, and tooth and gingival esthetics
Subject(s)
Humans , Female , Middle Aged , Denture Design , Denture, Complete , Dentures , Mouth RehabilitationABSTRACT
During clinical practice, when performing prosthetic rehabilitation with single crowns, improper reproduction of the dental contour by the dental laboratory is a common occurrence. Therefore, the present study evaluated the fidelity of the reproduction of the buccal contour in an upper left canine performed by three Dental Prosthesis Technicians (DPT) using the indirect laminate veneer technique. First, the DPTs confected the veneers based on a model obtained from the upper arch of a dental dummy, containing a replica of an upper left canine with a prosthetic preparation for a laminate veneer. Then, the same DPTs received other identical models, now with the replica of the upper left canine with no preparation, to be used as an anatomical reference for confecting the laminate veneers. The laminate veneers were then bonded to the plaster models and had their buccal contour individually measured. Measurements were also made of the buccal contour of the reference canine. The data were analyzed by ANOVA and the t-test (p = 0.05). Results showed 100 percent of buccal overcontour when the laminate veneers were compared to the reference canine, regardless of which DPT confected the veneer and regardless of using or not the anatomical reference. The DPTs who participated in the present study were unable to acomplish a faithful anatomical reproduction of the buccal contour, creating an overcontour in all samples. This situation may be responsible for increasing the probability of periodontal and esthetic harm in clinical practice.
Subject(s)
Humans , Crowns , Cuspid , Dental Prosthesis Design , Dental Veneers , Dental Impression Technique/standards , Dental Prosthesis Design/standards , Denture Design/standardsABSTRACT
The aim of this study was to evaluate the effect of different curing methods on the stress generated by the polymerization shrinkage of a restorative composite in two moments: immediately after light exposure and after 5 min. Photoactivation was performed using two different light sources: (1) xenon plasma arc (PAC) light (1,500 mW/cm2 - 3s) and (2) a quartz-tungsten-halogen (QTH) light with three light-curing regimens: continuous exposure (40 s at 800 mW/cm2 - CL); soft-start (10 s at 150 mW/cm2 and 30 s at 800 mW/cm2 - SS) and intermittent light [cycles of 4 s (2 s with light on at 600 mW/cm2 and 2 s of light off), for 80s - IL]. The composite resin was applied between two 5-mm diameter metallic rods, mounted in a servohydraulic machine. The maximum stress was recorded immediately after light exposure (FF) and after 5 min (5F). The results were submitted to ANOVA and Tukey's test (5 percent). For each method, the results obtained in FF and 5F were, respectively: CL (3.58 and 4.46 MPa); SS (2.99 and 4.36 MPa); IL (3.11 and 4.32 MPa) and PAC (0.72 and 3.27 MPa). The stress generated by the polymerization shrinkage during light exposure can be associated with the photoactivation method used. A significant increase in the stress level was observed during the post-curing period up to 5 min, for all evaluated methods.
Subject(s)
Composite Resins/radiation effects , Dental Stress Analysis , Light-Curing of Dental Adhesives/methods , Resin Cements/radiation effects , Curing Lights, Dental , Halogens , Materials Testing , Phase Transition , Time Factors , XenonABSTRACT
o objetivo do estudo foi avaliar a dureza Knoop e a profundidade de polimerização de compósitos contendo ORMOCER e compará-los àqueles tradicionais a base de Bis-GMA ou derivados. Foram selecionados dois compósitos contendo ORMOCER (Admira e Definite), um híbrido (Z250) e um microparticulado (A110). Corpos-de-prova cilíndricos (3mm de diâmetro X 5mm de altura) foram confeccionados em uma matriz bipartida e polimerizados de acordo com as instruções do fabricante em aparelho XL2500 (3M/ESPE). As amostras foram armazenadas por 24h a 37ºC. As medidas de microdureza Knoop foram obtidas com aparelho Micro Hardness Tester HMV (Shimadzu-Japão) utilizando carga de 50g durante 15s. Foram confeccionados 5 corpos-de-prova, nos quais 3 penetrações foram efetuadas nas regiões de superfície, 1mm , 2mm, 3mm e 4mm abaixo da mesma. Os resultados foram submetidos à análise de variância e Teste de Tukey (5 porcento). Pôde-se observar que, para todas as profundidades o compósito Z250 apresentou dureza superior em relação aos demais. A dureza dos compósitos Definite, Admira e A110 não defiriu estatisticamente até a profundidade de 2mm, após a qual A110 mostrou redução nos valores de dureza . De uma maneira geral, todos os materiais mostraram diminuição da dureza com o aumento da profundidade. Comparando com valores de dureza superficial, reduções significativas ocorreram nas profundidades de 2mm para Z250 e A110 e 3mm para Definite e Admira. Conclui-se que os compósitos a base de ORMOCER apresentaram valores de dureza intermediários e profundidade de polimerização satisfatória quando comparados aos valores obtidos pelos compósitos convencionais.
Subject(s)
Composite Resins , Dental Restoration, PermanentABSTRACT
O objetivo deste estudo foi avaliar a rugosidade superficial antes e após ensaio de escovação de dois compósitos a base de Ormocer e compará-los a compósitos a base de sistemas monoméricos tradicionais. O estudo comparou as marcas Admira e Definite com os compósitos baseados em sistemas de monoméricos tradicionais (Bis-GMA, Bis-EMA, UEDMA e TEGDMA): Z250 e A110. Oito amostras de cada material com 4 mm em diâmetro por 2 mm em altura foram confeccionadas em uma matriz metálica rosqueável. Depois de 24 horas, as amostras foram submetidas a polimento e análise da rugosidade superficial inicial (Ra, µm) através de um profilômetro antes do ensaio de escovação mecânica (30.000 ciclos). Após o ensaio de escovação as amostras foram levadas mais uma vez ao profilômetro para mensuração da rugosidade superficial final. Os resultados foram submetidos a ANOVA e ao teste de Tukey (5 por cento). O compósito Admira apresentou a maior rugosidade superficial antes do ensaio de escovação mecânica (0,132 µm), média estatisticamente superior ao compósito A110 (0,082 µm). Os compósitos Definite (0,110 µm) e Z250 (0,105 µm) não apresentaram diferenças estatísticas entre si nem aos demais compósitos avaliados. Nenhuma diferença estatística foi observada após o ensaio de escovação entre os compósitos Definite (0,178 µm), Z250 (0,187 µm), Admira (0,181 µm), e A110 (0,193 µm). Todos os compósitos apresentaram aumento estatisticamente significante da rugosidade superficial após o ensaio de escovação mecânica.