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Some light-emitting diode polymerization lights have been promoted as multiple peak or polywave lights that use multiple light-emitting diodes to produce both violet and blue light. However, whether the addition of violet light is required to light-activate resin cements that use bis(4-methoxybenzoyl)diethylgermane (Ivocerin) as the photoinitiator is unclear.This in vitro study evaluated the effect of violet, blue, or a combination of violet and blue light through ceramic on the degree of conversion of 2 resin cements that use either camphorquinone or Ivocerin as the photoinitiator.A Bluephase Style polywave light-emitting diode polymerizing unit delivering 6.4 J/cmAll factors had a significant effect (P.001). Increasing the ceramic thickness decreased the degree of conversion only for RelyX Veneer cement (P.001). The effect of the thickness of ceramic was most noticeable when just violet light was delivered to RelyX Veneer. A significant reduction (P.001) was found in the degree of conversion of RelyX Veneer when just violet light was delivered. Variolink Esthetic LC had significantly higher degree of conversion values than RelyX Veneer, irrespective of the light type used (P.001).A multiple-peak light is not required to photopolymerize a resin cement that uses either camphorquinone or Ivocerin as its photoinitiator. Adding the violet light produced no significant increase in the degree of conversion of the Variolink Esthetic LC cement.

This study evaluated the effect of using two different pre-heating methods on the three resin-based composite (RBCs). Three paste viscosity bulk-fill RBCs (VisCalor Bulk [VC]; VOCO; x-tra fil Caps [XF], VOCO; Filtek One Bulk Fill [FO], 3 M) were pre-heated using either a VisCalor Dispenser (VOCO) to 65 °C, or the Caps Warmer (VOCO) to 37 °C, 54 °C, or 68 °C. The temperature inside the capsules and cavity was monitored before and after insertion into the matrix. Within 30 s of inserting the RBC, they were light-activated using a VALO (Ultradent) curing light for 20 s. The post-gel shrinkage (Shr - %), Flexural Strength (FS - MPa), Elastic Modulus (E - MPa), degree of conversion (DC - %), Knoop Hardness (KH - N/mm

Introducao A hemovigilância consiste em um conjunto de metodologias de vigilância referente ao ciclo do sangue, a qual objetiva obter e disponibilizar informacoes sobre as Reacoes Adversas ocorridas dentro do processo, visando prevenir sua ocorrencia ou repeticao, melhorando e aumentando a seguranca do doador e receptor. Sobretudo, em relacao as reacoes transfusionais que podem repercutir como complicacoes agudas graves no quadro paciente. Objetivo Avaliar as reacoes transfusionais (RT) notificadas ao Sistema de Notificacao em Vigilância Sanitaria - NOTIVISA em um hospital privado de Belem atendido pelo IHEBE e o papel do enfermeiro na seguranca do paciente. Metodo Estudo descritivo retrospectivo, com analise das RTs notificadas para o NOTIVISA no periodo de Janeiro de 2019 a dezembro de 2020 de um hospital privado de Belem. Os dados foram tabulados em planilhas e graficos do Microsoft Office Excel 2016. Resultados Neste periodo foram realizadas 11.143 transfusoes e notificadas 54 reacoes transfusionais (RT) (0,48%), destas 02 foram reacoes do tipo tardias e 42 do tipo imediatas. Estavam associadas as hemacias 35%, plasma 1% e plaquetas 64%. As RTs mais prevalentes foram Reacao Febril nao Hemolitica (40%) e alergica (33%). Os sinais e sintomas mais relatados foram febre, urticaria, calafrios, prurido e hipertensao. Em relacao ao sexo e idade nao foram observadas diferencas significativas. Discussao Durante a analise das RTs 54 foram confirmadas e 06 nao foram confirmadas, ficando 01 como improvavel, 2 como possivel, 1 como inconclusiva e 2 foram descartadas. O descarte da bolsa pos transfusao impossibilitou a realizacao da hemocultura, o que levou a dificuldade em concluir efetivamente as respectivas RTs. Alem do registro de alteracao dos sinais e sintomas incomuns, como formigamento, vertigem e rebaixamento do nivel de consciencia. Conclusao Conclui-se a necessidade constante de treinamentos junto a equipe de saude do hospital, com destaque a equipe de enfermagem, a qual, em sua maioria, realiza a notificacao e acompanha o paciente 24h, com enfase nas condutas frente as reacoes transfusionais. O que proporcionara maior qualidade na investigacao da RT e maior seguranca e qualidade aos pacientes submetidos a transfusao sanguinea.

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior A fotoativação é um passo importante nos procedimentos restauradores diretos e indiretos. Os equipamentos utilizados para este fim, as fontes fotoativadoras, apresentam características como potência, espectro de emissão, irradiância e formato do equipamento diferentes entre si. Essas características podem influenciar nos procedimentos odontológicos, o que torna importante o estudo e entendimento destes equipamentos para o melhor uso na associação aos materiais restauradores. O objetivo geral desta tese foi avaliar e caracterizar o desempenho de diferentes fontes fotoativadoras na ativação de restaurações diretas e indiretas. Três objetivos integram este estudo: Objetivo específico 1: avaliar o efeito do tipo de fonte fotoativadora e do preparo de amostras na microdureza e grau de conversão em diferentes profundidades e regiões de restaurações em dentes posteriores com resina composta bulk-fill. Objetivo específico 2: Avaliar a influência de diferentes cerâmicas, espessuras e tratamentos de superfície na transmissão de luz em diferentes comprimentos de onda violeta e azul. Objetivo específico 3: Avaliar o efeito da emissão de apenas luz violeta, apenas luz azul ou da combinação de ambas por uma fonte fotoativadora de múltiplos espectros, no grau de conversão de cimentos resinosos que apresentam diferentes fotoiniciadores. A partir destes estudos pode-se concluir que o preparo de amostras incluídas em resina de poliestireno para testes de dureza e grau de conversão reduzem a percepção de diferenças entre as diferentes técnicas, já na utilização de método sem inclusão e sem polimento da amostra é possível detectar diferenças produzidas pela fotoativação em áreas profundas da restauração, como caixas proximais de restaurações Classe II. De acordo com o segundo estudo, há uma rápida redução logarítmica em transmissão de luz à medida que a espessura de cerâmica aumenta, transmitindo pouca luz através de 1,5 mm de ambas as cerâmicas testadas. Nos comprimentos de onda curtos a transmissão de luz é ainda menor. A cerâmica Celtra Duo, após glaze, apresenta maior brilho de superfície comparado a IPS e.max CAD, porém não há correlação entre o brilho de superfície e a transmissão de luz. E por fim, demonstrou-se que não é necessária fonte fotoativadora de múltiplos picos para polimerizar o cimento resinoso Variolink Esthetic LC e, o cimento resinoso RelyX Veneer não tem seu grau de conversão beneficiado pela emissão de luz violeta. Photoactivation is an important step for direct and indirect restorative procedures. The light-curing units used for this purpose present characteristics such as radiant power, emission spectrum, irradiance, and equipment design which are different among themselves, and have influenced the procedures. The general objective of this thesis was to evaluate and characterize the performance of different light-curing units in the activation of direct and indirect restorations. Three objectives integrate this study: Specific objective 1: To evaluate the effect of the sample preparation and light-curing units on the Knoop hardness and degree of conversion at different depths and regions of bulk-fill resin-based composite restorations. Specific objective 2: To evaluate the influence of thickness and surface condition on the transmission of violet and blue light through two ceramics. Specific objective 3: To evaluate the effect of delivering isolated violet, blue, or a combination of violet and blue light from a polywave® light-curing unit (LCU) through ceramic on the degree of conversion (DC) of two resin cements with different photoinitiators. Based on the results of these studies, the following conclusions can be drawn: preparation methods that embedded the samples in polystyrene resin and polished the specimens reduced the differences between the KH and DC values obtained by different preparation techniques. The use of the NotPol method was able to detect differences produced by light activation in deeper areas. According to the second study, there is a rapid logarithmic decline in light transmission as the ceramic thickness increases means that little useful light is transmitted through 1.5 mm of either ceramic. Even less of the shorter wavelengths of light are transmitted. Celtra Duo glazed ceramic had a higher surface gloss compared to IPS e.max CAD, however there is no correlation between surface gloss and light transmission. Finally, the third study demonstrated that a polywave® light is not required to cure Variolink Esthetic LC, and RelyX Veneer does not benefit from receiving violet light from the polywave® light. Tese (Doutorado) 2023-07-30

This study evaluated the effect of the design of the light-curing unit (LCU) and mouth opening on the properties of bulk-fill resin-based composites (RBCs).Eighty molars received a mesio-occlusal-distal preparation and were restored using two different bulk-fill RBCs, Opus Bulk Fill APS (FGM) and Filtek Bulk Fill One (3M Oral Care), using two different designs of LCU, straight (Valo Cordless [Ultradent]) and angled (Radii-Cal [SDI]). Two mouth openings of 25 and 45 mm at the incisors were used. Forty samples were sectioned mesiodistally. One half was immersed in tetrahydrofuran to examine the effect of the solvent on the RBCs (SE), and the other half to measure the degree of conversion (DC) in proximal and occlusal boxes using Fourier Transform Infrared spectroscopy. The other 40 samples were subjected to thermomechanical fatigue and immersed in silver nitrate to examine the gingival margin integrity (GMI) using SEM. The irradiance (mW/cm2) and emission spectrum (mW/cm2/nm) from the LCUs were measured using a MARC Resin Calibrator (BlueLight Analytics). DC data were analyzed by 3-way ANOVA and Tukey's test; SE and GMI were analyzed by an ANOVA on Ranks and Dunn test (α = 0.05).The DC values were similar in the occlusal and proximal boxes when using Valo Cordless , irrespective of RBC and the mouth opening used. Lower DC values were measured in proximal boxes when using Radii-Cal. The mouth opening had a greater effect on the irradiance delivered by Radii-Cal. Radii-Cal with 25-mm mouth opening had greater SE and GMI values, whereas the SE and GMI values obtained with Valo Cordless were unaffected by mouth opening.The choice of LCU did not influence the properties of tested bulk-fill RBCs when the 45-mm mouth opening was used. However, when using the 25-mm mouth opening, the choice of LCU did influence the properties of the RBCs.

Introducao Em 1970 Friedman et al. descreveram pela primeira vez a pratica de reservar componentes sanguineos para pacientes que se submeteriam a procedimentos cirurgicos. No ano de 2000, o IHEBE foi inaugurado e logo apos, a OMS (2002) sugeriu que as instituicoes criassem protocolos de acordo com a realidade de cada servico. Posteriormente (2015), o IHEBE elaborou o Protocolo de Reserva Cirurgica de Componentes Sanguineos (CS), atraves de reunioes com a equipe de enfermagem e com os medicos de cada clinica do Bloco Cirurgico dos hospitais a fim de evitar o desperdicio de materiais medico-hospitalares, consumo de reagentes imunohematologicos e de tempo dos recursos humanos, alem de reduzir a possibilidade da equipe estar executando um procedimento e ser surpreendida com a necessidade de transfusao de um CS em que nao foi solicitado reserva. Objetivo Avaliar a adesao das equipes hospitalares ao Protocolo de Reserva Cirurgica de Sangue e CS. Metodologia Estudo retrospectivo, descritivo, realizado no IHEBE no periodo de 01/01/2017 a 31/12/2020 em 02 hospitais privados de Belem/PA. Foram selecionados todos os procedimentos cirurgicos que constam no Protocolo de Reserva Cirurgica CS. Todos os dados foram tabulados em planilhas do programa Microsoft Office Excel 2013. Com isso, foram realizadas analises comparativas do quantitativo solicitado pela equipe medica e o quantitativo preconizado no Protocolo para verificacao da sua efetividade e adesao. Resultados e discussao Em 2017, no hospital A, foram avaliados 737 reservas de CS para cirurgias eletivas, destes 578 (66%) apresentaram conformidade com a quantidade constante no Protocolo de Reserva Cirurgica de CS; No ano de 2018 foram avaliados 941 reservas, sendo 639 (69%) conformes; No ano de 2019 foram avaliados 1.177 reservas, sendo 881 (75%) conformes e no ano 2020 foram avaliados 877 reservas, sendo 663 (76%) conformes. Em 2017, no hospital B, foram avaliados 252 reservas de CS para cirurgias eletivas, no ano de 2017, destes 162 (63%) apresentaram conformidade com a quantidade constante no Protocolo de Reserva Cirurgica de CS; No ano de 2018 foram avaliados 259 reservas, sendo 169 (65%) conformes; No ano de 2019 foram avaliados 351 reservas, sendo 259 (74%) conformes e no ano 2020 foram avaliados 275 reservas, sendo 215 (78%) conformes. A construcao deste indicador demonstra que em ambos os hospitais houve um incremento na taxa de conformidade ao Protocolo demonstrando melhor adesao sobre esta boa pratica e maior organizacao por parte da Agencia Transfusional e conscientizacao mais efetiva da equipe medica acerca do uso racional dos CS. Conclusao A implantacao do Protocolo de Reserva Cirurgica de Sangue e CS contribuiu para minimizacao das solicitacoes em carater de emergencia durante o procedimento e no pos-operatorio para garantir a seguranca transfusional do paciente e das Instituicoes envolvidas. Melhores taxas de adesao ao Protocolo sao asseguradas atraves de revisoes periodicas do documento, alem de sua inclusao no programa de educacao continuada de modo a manter as equipes cirurgicas atualizadas.

To compare shrinkage stress, cuspal strain and fracture load of weakened premolars restored with different conventional and bulk-fill composite resins and restorative techniques.Fifty premolars received a 4.0 x 3.5mm mesio-occlusal-distal (MOD) class II preparation. The lingual and buccal cups were internally weakened. Specimens were restored according to the following 5 groups: Filtek Z350 XT/10 increments; Filtek Z350 XT/8 increments (both 3M Oral Care); Filtek Bulk Fill Flowable Restorative + Filtek Z350 XT (both 3M Oral Care); SDR + Spectra Basic (Dentsply Sirona); and Tetric N-Ceram Bulk Fill (Ivoclar Vivadent). Cuspal strains were measured using strain gauges (n = 10). After restoration, specimens were submitted to thermal/mechanical cycles and fractured. Post-gel shrinkage of the composites was determined. Additionally, residual shrinkage strains and stresses were analyzed using three-dimensional finite element analysis (3D-FEA). The data were statistically analyzed using one-way ANOVA and Tukey's HSD (α = 0.05).One-way ANOVA revealed statistically significant differences among composite resins (p0.001) for the post-gel shrinkage. Filtek Z350 XT had the highest post-gel shrinkage and no difference was found between Spectra Basic and Tetric N-Ceram Bulk Fill (p = 0.110). The Filtek Z350 XT/10 increments, Filtek Z350 XT/8 increments and Filtek Bulk Fill Flowable Restorative/Filtek Z350 XT had statistically significantly higher cuspal deformation values when compared to the SDR/Spectra Basic and Tetric N-Ceram Bulk Fill techniques. 3D-FEA confirmed higher stress levels in the incrementally filled conventional restorations. Fracture loads were not statistically significantly different.The bulk-fill restoration techniques resulted in less cuspal strain and stress than the incremental technique with conventional composite resin. Fracture resistance was not affected by the restorative techniques.

To describe a method of measuring the molar cusp deformation using micro-computed tomography (micro-CT), the propagation of enamel cracks using transillumination, and the effects of hygroscopic expansion after incremental and bulk-filling resin composite restorations.Twenty human molars received standardized Class II mesio-occlusal-distal cavity preparations. They were restored with either a bulk-fill resin composite, X-tra fil (XTRA), or a conventional resin composite, Filtek Z100 (Z100). The resin composites were tested for post-gel shrinkage using a strain gauge method. Cusp deformation (CD) was evaluated using the images obtained using a micro-CT protocol and using a strain-gauge method. Enamel cracks were detected using transillumination.The post-gel shrinkage of Z100 was higher than XTRA (P 0.001). The amount of cusp deformation produced using Z100 was higher compared to XTRA, irrespective of the measurement method used (P 0.001). The thinner lingual cusp always had a higher CD than the buccal cusp, irrespective of the measurement method (P 0.001). A positive correlation (r = 0.78) was found between cusp deformation measured by micro-CT or by the strain-gauge method. After hygroscopic expansion of the resin composite, the cusp displacement recovered around 85% (P 0.001). After restoration, Z100 produced more cracks than XTRA (P = 0.012).Micro-CT was an effective method for evaluating the cusp deformation. Transillumination was effective for detecting enamel cracks. There were fewer negative effects of polymerization shrinkage in bulk-fill resin restorations using XTRA than for the conventional incremental filling technique using conventional composite resin Z100.Shrinkage and cusp deformation are directly related to the formation of enamel cracks. Cusp deformation and crack propagation may increase the risk of tooth fracture.

Background Tooth sensitivity commonly occurs during and immediately after dental bleaching. The authors conducted a trial to compare tooth sensitivity after in-office bleaching after the use of either a topical dipyrone or placebo gel. Methods A split-mouth, triple-blind, randomized, multicenter clinical trial was conducted among 120 healthy adults having teeth that were shade A2 or darker. The facial tooth surfaces of the right or left sides of the maxillary arch of each patient were randomly assigned to receive either topical dipyrone or placebo gel before 2 in-office bleaching sessions (35% hydrogen peroxide) separated by 2 weeks. Visual analog and numerical rating scales were used to record tooth sensitivity during and up to 48 hours after bleaching. Tooth color change from baseline to 1 month after bleaching was measured with shade guide and spectrophotometer measures. The primary outcome variable was absolute risk of tooth sensitivity. An intention-to-treat analysis was used to analyze data from all patients who were randomly assigned to receive the dipyrone and placebo gels. Results No statically significant difference was found in the absolute risk of tooth sensitivity between the dipyrone and placebo gels (83% and 90%, respectively, P = .09; relative risk, 0.92; 95% confidence interval, 0.8 to 1.0). A whitening effect was observed in both groups with no statistically significant difference ( P > .05) between them. No adverse effects were observed. Conclusion Topical use of dipyrone gel before tooth bleaching, at the levels used in this study, did not reduce the risk or intensity of bleaching-induced tooth sensitivity. Practical Implications Topical application of dipyrone gel does not reduce bleaching-induced tooth sensitivity.

This study evaluated the effect of gamma radiation and endodontic treatment on the microhardness and flexural strength of human and bovine root dentin. Forty single-rooted human teeth and forty bovine incisor teeth were collected, cleaned and stored in distilled water at 4 °C. The human and bovine teeth were divided into 4 groups (n=10) resulting from the combination of two study factors: first, regarding the endodontic treatment in 2 levels: with or without endodontic treatment; and second, radiotherapy in two levels: with or without radiotherapy by 60 Gy of Co-60 gamma radiation fractioned into 2 Gy daily doses five days per week. Each tooth was longitudinally sectioned in two parts; one-half was used for the three-point bending test and the other for the Knoop hardness test (KHN). Data were analyzed by 3-way ANOVA and Tukey HSD test (α=0.05). No significant difference was found for flexural strength values. The human dentin had significantly higher KHN than the bovine. The endodontic treatment and radiotherapy resulted in significantly lower KHN irrespective of tooth origin. The results indicated that the radiotherapy had deleterious effects on the microhardness of human and bovine dentin and this effect is increased by the interaction with endodontic therapy. The endodontic treatment adds additional negative effect on the mechanical properties of radiated tooth dentin; the restorative protocols should be designed taking into account this effect. Resumo Este estudo avaliou o efeito da irradiação gama e tratamento endodôntico na microdureza e resistência à flexão de dentina radicular humana e bovina. Quarenta dentes humanos unirradiculares e quarenta dentes incisivos bovinos foram coletados, limpos e armazenados em água destilada a 4 °C. Os dentes humanos e bovinos foram divididos em 4 grupos (n=10) gerados pela combinação de dois fatores de estudo: tratamento endodôntico em 2 níveis: com ou sem tratamento endodôntico; e radioterapia em dois níveis: com ou sem radioterapia utilizando 60 Gy de radiação gama de Co-60 fracionado em 2 Gy por dia, cinco dias por semana. Cada dente recebeu um corte longitudinal, resultando em duas metades por raiz, sendo uma metade utilizada para o ensaio de flexão de três pontos e a outra para o teste de dureza Knoop (KHN). Os dados foram analisados por ANOVA e teste de Tukey (α=0,05). Nenhuma diferença estatística foi encontrada para todos os fatores de resistência à flexão. A dentina humana teve KHN significativamente maior do que a dentina bovina. O tratamento endodôntico e radioterapia resultaram em significativa menor KHN, independentemente do tipo de dente. Os resultados indicaram que a radioterapia produziu efeitos deletérios sobre a microdureza da dentina humana e bovina e este efeito é exacerbado pela interação com a terapia endodôntica. O tratamento endodôntico causou efeito negativo adicional à radioterapia nas propriedades mecânicas da dentina. Este aspecto deve ser considerado no momento de se restaurar dentes tratados endodonticamente que receberam terapia endodôntica

Objectives Curing lights cannot be sterilized and should be covered with an infection control barrier. This study evaluated the effect of barriers when applied correctly and incorrectly on the radiant power (mW), irradiance (mW/cm2), emission spectrum (mW/nm), and beam profile from a multi-peak light-curing unit (LCU). Methods Five plastic barriers (VALO Grand, Ultradent; TIDIShield, TIDI Products; Disposa-Shield, Dentsply Sirona; Cure Sleeve, Kerr; Stretch and Seal, Betty Crocker) and one latex-based barrier (Curelastic, Steri-Shield) were tested. The radiant power (mW) and emission spectrum (mW/nm) from one multi-peak LCU (VALO Grand, Ultradent) was measured using an integrating sphere. LCU tip internal diameter (mm) was measured, then the tip area and irradiance (mW/cm2) were calculated. The beam profiles were measured using a laser beam profiler. Results When applied correctly, the plastic barriers reduced the radiant power output by 5–8%, and the latex-based barrier by 16%. When the plastic seam or barrier opaque face was positioned over the LCU tip, the power output was reduced by 8–11%. When the plastic barriers were wrinkled, the power output was significantly reduced by 14–26%. The wrinkled latex-based barrier reduced by 28%, and further reduced the violet light. The beam profiles illustrated the importance of correctly barrier use without wrinkles over the tip. Conclusions Plastic barriers applied correctly reduced the light output (mW) by 5–8%. The barriers applied incorrectly significantly reduced the light output by 14–26%. The latex-based barrier wrinkled also reduced the amount of violet light. Clinical relevance Infection control curing light barriers should be used to prevent cross-infection between patients. However, they must be applied correctly to reduce their negative effects on the light output.

The combination of the restoration location, the hand preference of the operator using the light-curing unit (LCU), and the design of the LCU all can have an impact on the amount of the light delivered to the restoration. To evaluate the effect of left-handed or right-handed users, the position of the operator (dentist or assistant), and the LCU design on the irradiance, radiant exposure and emission spectrum delivered to the same posterior tooth. Two light emitting diode (LED) LCUs were tested: an angulated monowave LCU Radii-Cal (SDI, Victoria, Australia) and a straight aligned multi-peak LCU Valo Cordless (Ultradent, South Jordan, UT, USA). The irradiance values (mW/cm2), radiant exposure (J/cm2) and emission spectrum were measured using a sensor in maxillary left second molar tooth. The irradiance and radiant exposure were analyzed using three-way ANOVA followed by Tukey test (a=0.05). The emission spectra (nm) were analyzed descriptively. The interaction between LCU design, operator position, and hand preference significantly influenced the irradiance and radiant exposure (P

Objectives This study aimed to develop a method to induce carious lesions in the pulpal floor dentin of a class II cavity preparation, and to determine the effects of this carious lesion on the biomechanical behavior of the dental composite restoration. Methods The pulpal floor dentin of class I cavities in sound third molars were demineralised with acetic acid for 35 days followed by a 7-day exposure to pooled human saliva biofilm and demineralization was verified by micro-CT. Subsequently, the proximal walls were removed forming a class II cavity and the caries lesion was left intact or was completely removed prior to restoration with a bulk-fill dental composite (n = 10). Cuspal deflection was assessed by strain-gauge and micro-CT imaging. The presence of enamel cracks was assessed by transillumination before and after restoration, and again after 1,200,000 cycles of mechanical fatigue in a chewing simulator. Finally, resistance to fracture by axial compressive loading and failure mode was determined. Data were analyzed by 2-way repeated measures ANOVA, Fisher’s exact test, and t-test (α = 0.05). Results The presence of carious lesions had no significant effect upon cuspal deflection, formation of enamel cracks, and fracture strength of the dental composite restorations. The restorative procedure increased the number of enamel cracks, which was not affected by mechanical cycling. Significance Maintaining carious lesions does not affect the biomechanical behavior of class II restorations performed with bulk-fill dental composite.

To compare flowable and regular paste bulk-fill resin composites with old and new generation conventional composites that use incremental filling techniques for direct restoration of endodontically-treated teeth.Four resin composites produced by the same company (3M-ESPE) were used: two conventional resin composites (old formulation, Z100, and new nanofilled formulation, Filtek Supreme XT); and two bulk-fill resin composites (flowable composite, Filtek Bulk-fill Flowable associated with Filtek Supreme, and regular paste, Filtek Bulk-fill Posterior). Elastic modulus (E), Vickers hardness (VH), post-gel shrinkage (Shr), diametral tensile strength (DTS) and compressive strength (CS) were determined (n= 10) and statistically analyzed using ANOVA and Tukey's test (α=0.05). Shrinkage stresses were analyzed using non-linear finite element analysis.Filtek Bulk-fill flowable and Filtek Supreme XT had higher CS than Z100 and Filtek Bulk-fill Posterior. Z100 and Filtek Supreme XT had higher DTS than Filtek Bulk-fill Posterior. Filtek Bulk-fill flowable had the lowest values and Z100 the highest E and Shr. Z100 resulted in higher stresses in the enamel and in root dentin close to the pulp chamber than the other filling techniques. Filtek Bulk-fill Flowable resulted in lower stress than other resin composites.Using bulk-fill composites, especially flowable resin composite, created lower stresses in restored endodontically-treated teeth. Clinicians, when deciding for direct restoration of endodontically-treated teeth, may choose the bulk-fill composite to decrease undesirable effects of direct restoration while simplifying filling procedure.

SUMMARY Objectives: To analyze the effect of pulp-capping materials and resin composite light activation on strain and temperature development in the pulp and on the interfacial integrity at the pulpal floor/pulp-capping materials in large molar class II cavities. Methods: Forty extracted molars received large mesio-occlusal-distal (MOD) cavity bur preparation with 1.0 mm of dentin remaining at the pulp floor. Four pulp-capping materials (self-etching adhesive system, Clearfil SE Bond [CLE], Kuraray), two light-curing calcium hydroxide cements (BioCal [BIO], Biodinâmica, and Ultra-Blend Plus [ULT], Ultradent), and a resin-modified glass ionomer cement– (Vitrebond [VIT], 3M ESPE) were applied on the pulpal floor. The cavities were incrementally restored with resin composite (Filtek Z350 XT, 3M ESPE). Thermocouple (n=10) and strain gauge (n=10) were placed inside the pulp chamber in contact with the top of the pulpal floor to detect temperature changes and dentin strain during light curing of the pulp-capping materials and during resin composite restoration. Exotherm was calculated by subtracting postcure from polymerization temperature (n=10). Interface integrity at the pulpal floor was investigated using micro-CT (SkyScan 1272, Bruker). The degree of cure of capping materials was calculated using the Fourier transform infrared and attenuated total reflectance cell. Data were analyzed using one-way analysis of variance followed by the Tukey test (α=0.05). Results: Pulpal dentin strains (μs) during light curing of CLE were higher than for other pulp-capping materials (p Conclusions: Light curing of pulp-capping materials caused deformation of pulpal dentin and increased pulpal temperature in large MOD cavities. Shrinkage of the resin composite restoration caused debonding of BIO from the pulpal floor.

Tooth sensitivity commonly occurs during and immediately after dental bleaching. The authors conducted a trial to compare tooth sensitivity after in-office bleaching after the use of either a topical dipyrone or placebo gel.A split-mouth, triple-blind, randomized, multicenter clinical trial was conducted among 120 healthy adults having teeth that were shade A2 or darker. The facial tooth surfaces of the right or left sides of the maxillary arch of each patient were randomly assigned to receive either topical dipyrone or placebo gel before 2 in-office bleaching sessions (35% hydrogen peroxide) separated by 2 weeks. Visual analog and numerical rating scales were used to record tooth sensitivity during and up to 48 hours after bleaching. Tooth color change from baseline to 1 month after bleaching was measured with shade guide and spectrophotometer measures. The primary outcome variable was absolute risk of tooth sensitivity. An intention-to-treat analysis was used to analyze data from all patients who were randomly assigned to receive the dipyrone and placebo gels.No statically significant difference was found in the absolute risk of tooth sensitivity between the dipyrone and placebo gels (83% and 90%, respectively, P = .09; relative risk, 0.92; 95% confidence interval, 0.8 to 1.0). A whitening effect was observed in both groups with no statistically significant difference (P.05) between them. No adverse effects were observed.Topical use of dipyrone gel before tooth bleaching, at the levels used in this study, did not reduce the risk or intensity of bleaching-induced tooth sensitivity.Topical application of dipyrone gel does not reduce bleaching-induced tooth sensitivity.

This study measured the radiant power (mW), irradiance (mW/cm2) and emission spectra (mW/cm2/nm) of 22 new, or almost new, light curing units (LCUs): - Alt Lux II, BioLux Standard, Bluephase G2, Curing Light XL 3000, Demetron LC, DX Turbo LED 1200, EC450, EC500, Emitter C, Emitter D, KON-LUX, LED 3M ESPE, Led Lux II, Optilight Color, Optilight Max, Optilux 501, Poly Wireless, Radii cal, Radii plus, TL-01, VALO Cordless. These LCUs were either monowave or multiple peak light emitting diode (LED) units or quartz-tungsten-halogen LCUs used in anterior and posterior teeth. The radiant power emitted by the LCUs was measured by a laboratory grade laser power meter. The tip area (cm²) of the LCUs was measured and used to calculate the irradiance from the measured radiant power source. The MARC-Patient Simulator (MARC-PS) with a laboratory grade spectrometer (USB4000, Ocean Optics) was used to measure the irradiance and emission spectrum from each LCU three times at the sensor located on the facial of the maxillary central incisors and then separately at the occlusal of a maxillary second molar. The minimum acceptable irradiance level was set as 500 mW/cm2. Irradiance data was analyzed using two-way ANOVA and the radiant power data was analyzed by one-way ANOVA followed by Tukey test (a=0.05). In general, the irradiance was reduced at the molar tooth for most LCUs. Only the Valo, Bluephase G2 and Radii Plus delivered an irradiance similar to the anterior and posterior sensors greater than 500 mW/cm2. KON-LUX, Altlux II, Biolux Standard, TL-01, Optilux 501, DX Turbo LED 1200 LCUs delivered lower irradiance values than the recommended one used in molar region, KON-LUX and Altlux II LCUs used at the maxillary incisors. Bluephase G2 and Optilight Max delivered the highest radiant power and KON-LUX, Altlux II and Biolux Standard delivered the lowest power. The emission spectrum from the various monowave LED LCUs varied greatly. The multi-peak LCUs delivered similar emission spectra to both sensors. Resumo Este estudo mediu a potência (mW), irradiância (mW/cm2) e espectro da luz (mW/cm2/nm) emitida por 22 fontes de luz (Alt Lux II, BioLux Standard, Bluephase G2, Curing Light XL 3000, Demetron LC, DX Turbo LED 1200, EC450, EC500, Emitter C, Emitter D, KON-LUX, LED 3M ESPE, Led Lux II, Optilight Color, Optilight Max, Optilux 501, Poly Wireless, Radii cal, Radii plus, TL-01, VALO Cordless) disponíveis comercialmente. A potência emitida pelas fontes de luz foi medida usando um medidor laboratorial de potencia com grade a laser. A área (cm²) da ponta ativa efetiva das fontes de luz foi medida com paquímetro digital e utilizada para calcular a irradiância emitida. O simulador de paciente-MARC (MARC - PS) com espectrómetro (USB4000, Ocean Optics) foi usado para medir a irradiância e o espectro de luz emitida por cada fonte de luz na região anterior e posterior. Esta medição foi repetida por três vezes em dois sensores localizados na região anterior e posterior da arcada dentária. Os dados de irradiância foram analisados utilizando análise de variância em dois fatores, e os dados de potência foram analisados com análise de variância em fator único seguido pelo teste de Tukey (a=0,05). As fontes de luz Valo, Bluephase G2, Radii Plus emitiram irradiância semelhante tanto na região anterior como posterior com valores superiores ao mínimo de 500 mW/cm2. Seis fontes de luz emitiram irradiância menor que o recomendado (500 mW/cm2) quando usadas na região posterior: Kon-lux, Altlux II, Biolux Standard TL-01, Optilux 501, DX Turbo LED 1200 e duas quando usadas na região anterior: Kon-lux e Altlux II LCUs. As fontes Bluephase G2, Optilight Max emitiram os maiores valores de potência e as fontes de luz Altlux II e Biolux Standard emitiram os menores valores de potência. O espectro de luz das fontes LED de espectro único variou de forma evidente entre as fontes. As fontes LED multi pico de espectro emitiram espectros de luz similar para ambos os sensores. A fotoativação na região posterior tende a reduzir substancialmente a irradiância da maioria das fontes de luzes testadas.

Avaliou-se o efeito da fonte fotoativadora e da microcirculação pulpar simulada, na geração de calor na câmara pulpar sob restaurações de resinas compostas inseridas em incremento único. As fontes fotoativadoras (Bluephase G2, Ivoclar e VALO Cordless, Ultradent) foram caracterizadas quanto à irradiância e ao espectro de emissão utilizando MARC Resin Calibrator (MARCRC, BlueLight) em diferentes condições experimentais. A potência radiante foi caracterizada utilizando medidor de potência de laboratório a laser. O grau de conversão foi avaliado, utilizando FTIR, para avaliar a polimerização no topo e na base das amostras de resina composta. Para mensuração da temperatura pulpar, 40 molares humanos receberam preparo oclusal plano resultando em aproximadamente 2 mm de dentina remanescente. As restaurações foram realizadas com sistema adesivo auto-condicionante (Clear Fil SE Bond, Kuraray) e resina composta bulk fill, fluida (SDR, Dentsply) ou de viscosidade regular (AURA, SDI). A temperatura da câmara pulpar foi medida utilizando termopar tipo-J na presença ou ausência de microcirculação pulpar. O pico máximo de aumento de temperatura durante a fotoativação do sistema adesivo e da resina composta foram obtidos. Os dados foram analisados utilizando o teste t-Student, Análise de Variância em 2 e 3 fatores, todos os testes empregando α=0,05. A irradiância e a potência radiante emitidas pelas fontes fotoativadoras foram maiores sem interposição de dentina/ resina e menores através de 3 mm de resina composta sobrepondo 2 mm de dentina. Em geral, Bluephase G2 obteve maior irradiância e potência radiante que o VALO Cordless. As resinas compostas, as fontes fotoativadoras e a região avaliada influenciaram o grau de conversão, porém em todas as combinações o grau de conversão no topo e na base atingiram valores que confirmam a polimerização dos materiais testados. A simulação da microcirculação pulpar reduziu significativamente o aumento de temperatura na câmara pulpar. O aumento de temperatura mais elevado ocorreu na fotoativação durante o sistema adesivo. O VALO Cordless resultou em menor variação de temperatura durante a ativação do sistema adesivo somente sem simulação de microcirculação pulpar. A resina SDR permite maior transmissão de luz e alcançou maior grau de conversão do que a AURA. O aumento de 15 temperatura é menor para a fotoativação das resinas bulk fill do que do sistema adesivo. O ponto crítico no aumento de temperatura está na fotoativação do sistema adesivo, sendo que a presença de microcirculação pulpar afeta os resultados. We evaluated the effect of light curing units (LCUs) and presence of pulpal microcirculation, on pulp chamber temperature changes used by light activation of adhesive system and bulk fill composites used to restore molar teeth. The LCUs (Bluephase G2, Ivoclar and VALO Cordless, Ultradent) were characterized regarding their irradiance and emission spectrum using MARC resin calibrator under different experimental conditions. The radiant power was characterized using laser powermeter. The degree of conversion (DC) achieved on the top and bottom of the bulk fill composite resin was assessed using FTIR. The occlusal face of forty human molars were flattened until left 2.0mm of remaining dentin. Restorations were built up using self-etching adhesive system (ClearFil SE Bond, Kuraray) and bulk fill composite resin, a flowable (SDR, Dentsply) or regular viscosity (AURA, SDI). The pulp chamber temperature was measured using J-type thermocouple with or without pulpal microcirculation simulation. The maximum temperature rise during the light activation of the adhesive system and composite resin were recorded. Data were analyzed using t-Student test, two-way and three-way ANOVA, all analyses considered α= 0.05. The irradiance and radiant power emitted by LCUs was without any material interposed to top sensor and lowest when through the 3.0 mm of composite resin over 2.0mm of dentin. In general, Bluephase G2 had higher irradiance and radiant power than VALO Cordless. Composite resin, LCU, and the region affected the DC. Pulpal microcirculation simulation significantly the temperature rise. The highest temperature was found for light activation of by adhesive system. VALO Cordless resulted on lower temperature change during activation of adhesive system only in absence of pulpal microcirculation simulation. Therefore, pulpal microcirculation simulation can dissipated the heat, resulting in lower temperature changes. SDR allows more light transmission and achieved higher DC than AURA. The temperature rise was lower for light activation of bulk fill composite resins than when adhesive systems was used. The clinical relevance is the use pulpal microcirculation simulation is important in heat generation by light curing units and bulk fill resins, while the critical point in the increase in temperature is related to the light activation of adhesive system. Dissertação (Mestrado)

O objetivo foi propor método para mensuração da deflexão de cúspide utilizando microtomografia computadorizada (micro-CT) e de trincas em esmalte utilizando transiluminação de restaurações de resina composta. Vinte molares humanos receberam preparos padronizados classe II e restaurações com resina composta de incremento único (Xtrafil - XTRA) ou resina convencional (Filtek Z100 - Z100). Contração pós-gel das resinas compostas foi mensurada utilizando método de Extensometria. Deformação de cúspide foi mensurada por meio de novo protocolo empregando micro-CT e validado pelo método de extensometria. Trincas em esmalte foram detectadas pelo método de transiluminação. Contração pós-gél de Z100 foi superior a XTRA. Deformação de cúspide para Z100 foi superior à XTRA, independentemente dos métodos. A cúspide lingual apresentou maior deformação do que a vestibular. Os métodos de deformação de cúspide por micro-CT e Extensometria apresentaram alta correlação (r 0,78). A expansão higroscópica recuperou significativamente a deformação de cúspide, porém resultou em ampliação de trincas. Z100 resultou em maior ocorrência de trincas com maior extensão que XTRA. As trincas foram predominantemente horizontais, localizadas na região correspondente à base da cavidade, envolvendo principalmente o centro e a região distal. O método que emprega micro-CT provou ser viável e eficaz para avaliar deflexão de cúspide, assim como a transiluminação para detecção de trincas.Palavras-chave: Resinas Compostas. Polimerização. Microtomografia.

Analisar o efeito da fotoativação de materiais de proteção pulpar e da resina composta na deformação, temperatura pulpar e na integridade da interface de teto da câmara pulpar/materiais de proteção em molares com cavidades MOD com 1,0mm dentina na parede pulpar. Quatro materiais de proteção: adesivo auto-condicionante CLE, Clearfil SE Bond (Kuraray) 2 hidróxidos de cálcio fotoativados: BIO, Biocal (Biodinâmica); ULT, Ultrablend plus (Ultradent) e cimento de ionômero de vidro modificado por resina composta VIT, Vitrebond (3M-ESPE). As cavidades foram restauradas com resina composta (Filtek Z350 XT, 3M-Espe) (n10). Termopares e extensômetros foram utilizados para detectar mudanças de temperatura, deformação durante a fotoativação. A deformação dentinária (µS) durante a fotoativação de CLE foi maior que os outros materiais de proteção pulpar (P