Scoping review: Effect of surface treatments on bond strength of resin composite repair.

OBJECTIVE: to evaluate the existing evidence on surface treatment techniques employed in resin composite repair and their effect on the repair short- and long-term bond strength. DATA AND SOURCE: This scoping review was performed under the PRISMA-ScR guidelines for scoping reviews and registered on the Open Science Framework platform. STUDY SELECTION: A systematic search was conducted in PubMed, Embase, and Scopus and grey literature up to September 2022 without language or date restriction. In vitro studies comparing mechanical surface and/or chemical treatments on repair bond strength of resin composite were included. Studies evaluating experimental adhesive systems or resin composites were excluded. Selection of studies and data extraction were performed. Data from selected studies was qualitatively analyzed. RESULTS: A total of 76 studies were included in the qualitative analysis. Among the mechanical treatments, alumina blasting was the most frequently used, followed by silica coating and diamond bur. As for chemical treatments, dentin bonding systems were the most frequently evaluated, followed by universal adhesive systems and silane/ceramic primer. The combination of mechanical and chemical pre-treatments increased the repair bond strength of resin composite in both short- and long-term simulated aging scenarios. The evidence obtained from the included studies was classified as moderate quality, mainly due to the medium risk of bias observed across most of the studies. CONCLUSION: The techniques used to treat the surface of resin composites for repair are diverse. Incorporating a combination of mechanical and chemical pre-treatments resulted in superior repair bond strength of resin composite materials under both short- and long-term simulated aging conditions. CLINICAL SIGNIFICANCE: The analysis of evidence revealed significant variability among protocols for repairing resin composites. Utilizing both mechanical and chemical pre-treatment methods is important for enhancing the bond strength of resin composites during both short- and long-term simulated aging situations.

Color and surface roughness alterations of bulk-fill resin composites submitted to simulated toothbrushing with whitening dentifrices

Aim: To evaluate the surface roughness and color stability of bulk-fill resin composites after simulated toothbrushing with whitening dentifrices. The radioactive/relative dentin abrasion (RDA) and radioactive/relative enamel abrasion (REA) of dentifrices were also assessed. Methods: Specimens (n=10) of Tetric N Ceram Bulk Fill (TNCB), Filtek One Bulk Fill (FOB) resin composites, and Z100(Control) were prepared using a cylindrical Teflon matrix. Surface roughness (Ra, µm) was assessed by a roughness meter and the color evaluations (ΔEab , ΔE00 , WID ) were performed using a digital spectrophotometer based on the CIELAB system. Three measurements were performed per sample, before and after simulated toothbrushing with 3D Oral-B White Perfection (3DW) and Black is White (BW) dentifrices. The abrasivity (REA and RDA values) of the used dentifrices was also determined by the Hefferren abrasivity test. Results: The Ra values increased significantly in all resin composites after 3DW and BW toothbrushing. The acceptable threshold color varied among resin composites, and TNCB and Z100 presented the highest ΔEab and ΔE00 for BW dentifrice. The 3DW dentifrice was significantly more abrasive than BW dentifrice on enamel and dentin. Conclusions: simulated toothbrushing with tested whitening dentifrices increased the surface roughness at acceptable levels. The Tetric N Ceram Bulk-fill and Z100 composite showed the highest color alteration in BW. 3D White Perfection dentifrice was more abrasive on dentin and enamel than Black is White.

Are polywave light-emitting diodes more effective than monowave ones in the photoactivation of resin-based materials containing alternative photoinitiators? A systematic review.

OBJECTIVE: This systematic review aimed to analyze if using polywave light-emitting diodes (LED) to photoactivate resin-based materials (resin composites, adhesive systems, and resin cements) containing alternative photoinitiators provide better physicochemical properties than monowave ones. MATERIAL AND METHODS: Inclusion criteria were in vitro studies that evaluated the degree of conversion, microhardness and flexural strength in resin-based materials containing alternative photoinitiators and light-activated with mono and polywave LEDs. Exclusion criteria were studies that evaluated the physicochemical properties of composites through any material interposed between the LED and the resin composite and studies that exclusively compared different modes and/or light activation times. Selection of studies, data extraction, and risk-of-bias analysis was performed. Data from selected studies were qualitatively analyzed. A systematic search was performed in June 2021 using PubMed/Medline, Embase, Scopus, and ISI Web of Science databases and grey literature without language restriction. RESULTS: A total of 18 studies were included in the qualitative analysis. Nine studies used diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide (TPO) as an alternative photoinitiator for resin composite. Polywave LED improved the degree of conversion of resin composite compared to monowave in 9 of the included studies. Polywave LED improved the microhardness of resin composite compared to monowave in 7 of the included studies. Polywave LED improved the degree of conversion for 11 studies and microhardness of resin composite compared to monowave for 7 included studies. No differences in the flexural strength medium between poly and monowave LEDs were observed. The evidence was graded as low quality due to the high risk of bias for 11 studies. CONCLUSION: The existing studies, with their limitations, revealed that the polywave light-emitting diode maximizes activation, resulting in a higher degree of double-bond conversion and microhardness of resin composites containing alternative photoinitiators. However, the flexural strength of these materials is not influenced by the type of light activation device.

Bond strength of bulk-fill resin composites: the effect of cavity preparation and aging

Aim: Evaluating the resin-dentin bond strength of Class II conventional and bulk-fill composite restorations, using different cavity sizes before and after aging. Methods: Seventy-five human molars were distributed into groups according to the buccolingual width of the cavities, conservative (n=25) and extended (n=50). They were divided according to the restorative material: conventional (Z100/control group) or bulk-fill resin composites (Filtek Bulk Fill/FBF; Tetric N Ceram Bulk Fill/TNCBF; Filtek Bulk Fill Flow/FBFF; Surefill SDR flow/SDR). The restored teeth were sectioned on sticks (n=50 per restorative materials + width cavities group), half were stored in Water/Ethanol 75% for 30 days and the other half were submitted to the immediate microtensile bond strength (µTBS) test. Data were analyzed applying the Three-Way Analysis of Variance (ANOVA), Bonferroni test, test t, and Weibull analyses (p<0.05). Results: SDR and FBF presented lower µTBSvalues for extended preparation when compared to the conservative preparation, before aging. After aging, only for the FBFF, a decrease in the µTBSvalues was observed. Comparing the µTBSvalues, before and after aging, the SDR demonstrated lower µTBSvalues after aging when the conservative cavity was used. A decrease in the µTBSvalues was observed for the Z100, the FBF and, the FBFF, after aging, when the extended cavity was used. Conclusion: The effect of cavity preparation and aging on the resin-dentin of Class II is material dependent. Most of the bulk-fill resin composites evaluated presented a similar performance to the conventional resin composites for all the conditions of this study

Effect of universal adhesives and self-etch ceramic primers on bond strength to glass ceramics: A systematic review and meta-analysis of in vitro studies.

STATEMENT OF PROBLEM: To simplify dental procedures, multicomponent products such as universal adhesives and self-etch ceramic primers have been recommended for glass-ceramic bonding; however, studies have shown a wide range of results. PURPOSE: The purpose of this systematic review and meta-analysis was to analyze the in vitro bond strength promoted by hydrofluoric acid+silane-containing universal adhesives and a self-etch ceramic primer to glass-ceramics and compare it with that of conventional treatments. MATERIAL AND METHODS: A systematic search was conducted in the PubMed/Medline, Scopus, LILACS, and ISI Web of Science databases up to April 2021. In vitro studies assessing the resin-mediated bond to glass-ceramics by using a self-etch ceramic primer and hydrofluoric acid+silane-containing universal adhesives and/or compared with traditional hydrofluoric acid+glass-ceramic primers were included. Selection of studies, data extraction, and risk-of-bias analysis were performed. Statistical analysis was performed by using a review management software program using a random effects model (α=.05). RESULTS: A total of 33 studies were included in the qualitative analysis and 26 studies in the quantitative analysis. Bond strength to lithium disilicate ceramic was higher when a hydrofluoric acid+glass-ceramic primer was used than when using a hydrofluoric acid+silane-containing universal adhesive (P<.05), except when 9% to 10% acid concentration was used in combination with static aging (P=.100). A self-etch ceramic primer promoted bond strength values to lithium disilicate that were similar to those of the hydrofluoric acid+glass-ceramic primer (P>.100). CONCLUSIONS: Hydrofluoric acid+silane-containing universal adhesive was not as effective as the hydrofluoric acid+glass-ceramic primer in promoting bond strength to glass-ceramic. Bond strength values generated by a self-etch ceramic primer to glass-ceramic were similar to those generated by the conventional treatment.

Thirty-six-month clinical evaluation of posterior high-viscosity bulk-fill resin composite restorations in a high caries incidence population: interim results of a randomized clinical trial.

OBJECTIVES: This study compared the clinical performance of two bulk-fill (BF) and one conventional resin composite in a population with a high caries incidence. MATERIALS AND METHODS: A total of 138 class I and II restorations were performed and randomly divided into three groups (n = 46) with equal allocation: Filtek BF (FBF; 3M ESPE), Tetric EvoCeram BF (TBF; Ivoclar Vivadent), and control Filtek Z250 (Z250; 3M ESPE). The evaluations were performed using the USPHS and FDI criteria at baseline and after 12 and 36 months by a previously calibrated evaluator. The Friedman and Wilcoxon tests for paired data were used for statistical analysis (α = 0.05). RESULTS: The DMFT index at baseline was 9.44, with 87% from the decayed component. After 36 months, 108 restorations (n = 36) were evaluated. Two failures were observed for TBF at marginal adaptation and recurrence of caries, resulting in a survival rate of 94.44% and an annual failure rate (AFR) of 1.26%. No equivalence was observed between the criteria for surface roughness, marginal adaptation, and discoloration. CONCLUSIONS: The 36-month clinical performance of high-viscosity BF resin composites was comparable to conventional incremental-filled resin composites. The FDI criteria better presented the restorations' clinical success. However, in the case of failure, both criteria provided the same result. CLINICAL RELEVANCE: High-viscosity bulk-fill resin composites showed excellent performance after 36 months in a high caries incidence population. It can be considered a simplified alternative restoration method that reduces operating time and minimizes possible operator errors.

Clinical Performance of Bulk-Fill Resin Composite Restorations Using the United States Public Health Service and Federation Dentaire Internationale Criteria: A 12-Month Randomized Clinical Trial.

OBJECTIVE: This study was aimed to compare the 12-month clinical performance of two full-body bulk-fill resin composites Filtek bulk fill/3M ESPE (FBF) and Tetric EvoCeram bulk fill/Ivoclar Vivadent (TBF) and a conventional microhybrid resin composite Filtek Z250/3M ESPE (Z250) using the modified the United States Public Health Service (USPHS) and Federation Dentaire Internationale (FDI) criteria. Also, the agreement between the two evaluation criteria was evaluated at baseline and after 12 months of follow-up. MATERIALS AND METHODS: A total of 138 class I and II restorations were placed in posterior teeth (split-mouth design) of 46 volunteers following manufacturer's instructions and bonded with a self-etching bonding agent (Clear fill SE Bond/Kuraray). The restorations were evaluated at baseline and after 12 months of follow-up by three previously calibrated dentists (Cohen's K = 0.84). STATISTICAL ANALYSIS: Fisher's exact test and Pearson's Chi-squared test were used to evaluating the homogeneity of distribution of the clinical characteristics. Friedman's test was applied to evaluate differences among the resin composites. The results obtained for the USPHS and FDI criteria at the different observation times were compared using the Wilcoxon test. A level of significance of 0.05 was adopted for all tests. RESULTS: After 12 months (recall rate, 78.3%, n = 36 patients), the overall success rate was 99.07% for both criteria. Only one failed restoration (0.93%) was detected for each system during follow-up in the TBF group. CONCLUSION: The bulk-fill resin composites showed satisfactory clinical performance compared with conventional resin composite after 12 months. The percentage of the acceptable scores was significantly higher for the USPHS criteria, due to discrepancies in the score description for each criterion.

Bond strength of universal adhesive applied to dry and wet dentin: one-year in vitro evaluation

Aim: This study evaluated the influence of dentin wettability on the immediate and extended microtensile bond strength (mTBS) of a universal adhesive system used in the etch-and-rinse strategy. Methods: Twenty human third molars were selected and divided into four groups according to the adhesive system and dentin wettability. The mTBS values of each group were registered 24 h and one year after adhesive system application and resin composite block build-up (n=30). Data were analyzed by the t-test (p<0.05). Results: When both adhesive systems were compared, there was no statistically significant difference when they were applied following wet bonding (p>0.05). However, the dry bonding reduced µTBS values of the Adper Single Bond 2 adhesive (p<0.05). Regarding storage time, both groups presented similar µTBS values at 24 h and one year (p>0.05). Conclusions: Therefore, the Scotchbond Universal Adhesive can be applied to dry or wet dentin without compromising the etch-and-rinse bonding quality and the durability of the restorations

Influence of three treatment protocols for dental fluorosis in the enamel surface: an in vitro

Introduction: Dental fluorosis is an enamel alteration characterized with opaque stains caused by high exposures to fluoride during the dentition development. Aim : This in vitro study aimed to evaluate changes in the enamel surface of sound human teeth after three treatment protocols for dental fluorosis: microabrasion with 37% phosphoric acid and pumice, home bleaching with 10% carbamide peroxide, and a combination of these techniques. Methods : Thirty-eight specimens (5×5×2 mm) with enamel surface were obtained from 19 third molars. Thirty six specimens were randomized into three treatment groups (n= 12): MAB- enamel microabrasion; CP10- home bleaching; MAB+CP10- a combination of these techniques and two specimens not received treatment. Surface roughness and microhardness analyses were performed before and after treatment protocols. Two representative specimens from each group were evaluated by scanning electron microscopy (SEM). Analysis of variance and Tukey's tests were used for data analysis (p< 0.05). Results : All treatment protocols promoted an increased in enamel surface roughness (p< 0.02). MAB and MAB+CP10 showed a significant increase in the enamel microhardness (p< 0.04), while CP10 showed a microhardness lower than MAB and MAB+CP10 (p< 0.05). SEM images demonstrated a smoother surface from MAB and MAB+CP10 and, an irregular pattern of enamel erosion from CP10. Conclusions : The treatment protocols for dental fluorosis tested significantly changed the enamel roughness, microhardness and micromorphology.

Introdução: A fluorose dentária é uma alteração do esmalte caracterizada por manchas opacas causadas pela alta exposição aos íons fluoreto durante o desenvolvimento dentário. Objetivo : Este estudo in vitro objetivou avaliar mudanças na superfície do esmalte em dentes humanos hígidos após três protocolos de tratamento para a fluorose dentária: microabrasão com ácido fosfórico a 37% e pedra-pomes, clareamento caseiro com peróxido de carbamida a 10% e a associação destas técnicas. Métodos : Trinta e oito espécimes (5×5×2 mm) com superfície em esmalte foram obtidos a partir de 19 terceiros molares, sendo que dois não receberam tratamento e, trinta e seis foram randomizados em três grupos (n= 12): MAB- microabrasão do esmalte; CP10- clareamento caseiro; e MAB+CP10- associação destas técnicas. A rugosidade superficial e microdureza foram realizadas antes e após os protocolos de tratamento. Dois espécimes representativos de cada grupo foram avaliados por microscopia eletrônica de varredura (MEV). A análise de variância e teste de Tukey foram utilizados para análise dos resultados (p< 0,05). Resultados : Todos os protocolos de tratamento promoveram um aumento da rugosidade superficial do esmalte (p< 0,02). MAB e MAB+CP10 mostraram um aumento significativo da microdureza do esmalte (p< 0,04), enquanto que CP10 mostrou uma menor microdureza comparado ao MAB e ao MAB+CP10 (p< 0,05). As imagens de MEV demonstraram uma superfície mais lisa do MAB e MAB+CP10 e um padrão irregular do esmalte erodido para o CP10. Conclusão : Os protocolos testados para tratamento da fluorose dentária testados modificaram significativamente a rugosidade, microdureza e micromorfologia do esmalte.

The Impact of Radiotherapy in the in Vitro Remineralization of Demineralized Enamel

Objective: To evaluate the impact of radiotherapy on enamel around restorations of glass ionomer cement (GIC) and fluoride tooth paste (FTP). Material and Methods: Eighty enamel blocks were made and randomly distributed into two groups, according to the fluoride therapy, non-fluoride tooth paste (NFTP) and FTP (n=40) and in subgroups in conformity with radiation dose (0, 10, 30 and 60 Gy). Roughness and microhardness enamel analyses were conducted before radiotherapy. Enamel cavities were made and restored with two GIC (Ketac Molar Easy Mix or Vitremer). Enamel blocks were submitted to 10, 30 and 60 Gy. Then, artificial enamel caries lesions were created by a pH-cycling procedure and FTP or NFTP were used as treatment. The restored enamel blocks were submitted to final roughness and microhardness analyses. Roughness increase (ΔR) and hardness loss (ΔH) values of enamel were submitted to ANOVA and Tukey test (p=0.05). Results: The irradiated enamel group showed statistically higher ΔR (0.44 ±0.2) and ΔH (99.26±7.0) values compared to non-irradiated group (ΔR = 0.051±0.02; ΔH=66.16±12.7) when a resin-modified GIC and NFTP were used. Conclusion: Higher radiation dose increased dissolution of bovine enamel. The use of GIC associated with FTP decreased roughness and increased enamel hardness after radiotherapy.

Impact of radiotherapy on the bond strength of different adhesive systems to human dentin: one-year in vitro evaluation

Aim: The aim of this study is to evaluate the effect of radiotherapy on the bond strength of resin-based composite restorations to dentin, performed either 24 h or 1 year before or after radiation. Methods: Ninety-six posterior teeth were randomly distributed into the following groups: IB (n = 16), irradiated teeth were restored 1 year after x-ray application; NB (n = 16), not irradiated teeth were stored for 1 year and then restored. IA (n = 32), teeth were restored and irradiated at 24 h or 1 year after the restoration. NA (n = 32), teeth were restored, not irradiated, and tested as IA. Eight samples from each group were randomly assigned to either the three-step or two-step etch-and rinse adhesive system procedure. The irradiated specimens were subjected to 60 Gy of x-ray radiation fractionally. The restored teeth were vertically sectioned, and 1-mm2 resin­dentin sticks were obtained and submitted to the microtensile bond strength test. The bond strength data were analyzed by two-way analysis of variance (ANOVA) followed by Tukey's test (p < 0.05). Failure modes were examined by optical microscopy and scanning electron microscopy. Results: The IB group showed lower bond strength values compared to the NB group. The bond strength values between the adhesive systems were not statistically different. Conclusion: The application of radiation dose decreased the bond strength of the adhesive restorations to dentin when the bonding procedure was conducted 1 year after in vitro radiotherapy

The effect of a bleaching agent on the pigment removal and the bond strength of bulk-fill resin composites: an in vitro study / Efeito dos agentes clareadores na remoção de pigmentos e na resistência de união de resinas compostas bulk-fill: um estudo in vitro

Introduction: In order to simplify the technique, reduce the time required for direct adhesive restorations, bulk-fill resin composites have been developed be applied in bulk placement up to 4 mm increments. Objective: Evaluating the color change (ΔE) and the microtensile bond strength (μTBS) of bulk fill resin composites (BFRC) to dentin after the immersion in regular beverages and the application of bleaching systems. Method: Forty-five human molar teeth were randomly distributed in three groups according to the filling material (n=15): Filtek Bulk Fill, Tetric N Ceram Bulk Fill and Filtek Z100. The restored teeth were immersed in coffee, wine and distilled water (n=5) for 72 hours. The color parameters were measured using a spectrophotometer, having as basis the CIE L*a*b*, before and after tooth staining and application of bleaching processes. Subsequently, the teeth were sectioned to obtain the specimens for the microtensile testing. The ΔE values were analyzed applying the Kruskal-Wallis and the Wilcoxon tests, and the μTBS values were analyzed applying the ANOVA and the Bonferroni tests (p<0.05). Result: There were no significant differences in the ∆E values when comparing the BFRCs to the conventional resin composite (CRC) in most of the experimental groups. The ∆E values did not present significant differences before and after the application of bleaching processes for all the tested resin composites. The BFRCs presented higher μTBS values than the CRC after exposure to distilled water, wine and bleaching agent. Conclusion: The studied BFRCs presented similar color stability to the CRC. The BFRCs presented higher bond strength to the dentin than the CTC in most of the evaluated conditions. The bleaching agent was not effective in whitening the stained restored teeth.

Introdução: Em busca de simplificar a técnica, reduzir o tempo requerido para as restaurações adesivas, resinas compostas bulk-fill (RCBF) estão sendo desenvolvidas para serem aplicadas em incrementos com espessura de até 4 mm. Objetivo: Avaliar a alteração de cor (ΔE) e resistência de união (μTBS) de RCBF a dentina após imersão em bebidas e aplicação de um sistema clareador. Método: Foram utilizados 45 dentes molares humanos que foram distribuídos aleatoriamente em três grupos de acordo com o material restaurador (n=15): Filtek Bulk Fill, Tetric N Ceram Bulk Fill e Filtek Z100. Os dentes restaurados foram imersos em café, vinho e água destilada (n=5) durante 72 horas. Os parâmetros de cor foram mensurados utilizando um espectrofotômetro, tendo como base o CIE L*a*b*, antes e após o manchamento e aplicação dos agentes clareadores. Consequentemente, os dentes foram seccionados para a obtenção de espécimes para o teste de microtração. Os valores de ΔE foram analisados aplicando os testes de Kruskal-Wallis e Wilcoxon e os valores de μTBS foram analisados aplicando ANOVA e o teste de Bonferroni (p<0,05). Resultado: Não houve diferença significante nos valores de ∆E quando as RCBFs foram comparadas a resina composta convencional (RCC) na maioria dos grupos experimentais. Os valores de ∆E não apresentaram diferença estatística antes e após a aplicação do agente clareador para todas as resinas testadas. As RCBFs demonstraram maiores valores de μTBS comparado a RCC após exposição a água destilada, vinho e agente clareador. Conclusão: As RCBFs demonstraram uma similar estabilidade de cor quando comparado a RCC. As RCBFs apresentaram maior resistência de união a dentina que a RCC na maioria das condições avaliadas. O agente clareador não foi efetivo no clareamento dos dentes restaurados.

Bond Strength and Cytotoxicity of a Universal Adhesive According to the Hybridization Strategies to Dentin

Abstract This study evaluated application protocol (etch-and-rinse/ER and self-etching/SE) and dentin wettability (wet and dry) on microtensile bond strength (μTBS) and transdentinal cytotoxicity of ScotchbondTM Universal (SU) adhesive system. The μTBS values and fracture mode were registered 24 h after adhesive system application and resin composite block build-up (n=5). For analysis of transdentinal cytotoxicity, odontoblast-like MDPC-23 cells were seeded on pulpal surface of dentin discs (0.4 mm thick) adapted to artificial pulp chambers (n=8). The adhesive system was applied to occlusal surface, followed by 24-h incubation time. Cell viability (Alamar Blue) and morphology (SEM) were assessed. Adper Single Bond 2 and Clearfil SE Bond were used as positive controls of the ER and SE application protocols, respectively. No treatment was performed on negative control (NC) group. Data were analyzed by ANOVA and Tukey's tests (α=5%). Higher μTBS values were found for ER mode in comparison with SE protocol (p<0.05). Dentin wettability had no effect on bond strength of SU in both the ER and SE techniques (p>0.05). Most fractures involved hybrid layer and/or adhesive layer. Neither variable prevented the intense toxic effects of adhesive systems on MDPC-23 cultured cells, since intense reduction in cell viability (±88%) and severe alterations in cell morphology were observed for all groups compared to NC, with no differences among them (p>0.05). Therefore, it was concluded that application of SU following the ER protocol had better adhesive performance. However, this adhesive system featured intense transdentinal cytotoxicity to pulp cells, regardless of application protocol and dentin wettability.

Resumo Este estudo avaliou o protocolo de aplicação (convencional/ER e autocondicionante/SE) e o grau de umidade da dentina (úmida e seca) sobre a resistência de união à microtração (μTBS) e a citotoxicidade transdentinária do sistema adesivo ScotchbondTM Universal (SU). Os valores de μTBS e o modo de fratura foram registrados 24 h após aplicação do sistema adesivo e restauração com resina composta pela técnica incremental. Para avaliação da citotoxicidade transdentinária, células odontoblastóides MDPC-23 foram semeadas na face pulpar de discos de dentina (0,4 mm de espessura) adaptados a câmaras pulpares artificiais (n = 8). O sistema adesivo foi aplicado na superfície oclusal, seguido de incubação por 24 h. A viabilidade e morfologia celular foram avaliadas pelo teste de Alamar Blue e MEV, respectivamente. Adper Single Bond 2 e Clearfil SE Bond foram utilizados como controle positivo do protocolo de aplicação ER e SE, respectivamente. Nenhum tratamento foi realizado no grupo controle negativo (NC). Os dados foram analisados pelos testes de ANOVA e Tukey (α = 5%). Maiores valores de μTBS foram encontrados para o modo ER em comparação com o protocolo SE (p < 0,05). O grau de umidade da dentina não apresentou efeito na resistência de união do SU em ambos os protocolos ER e SE (p > 0.05). A maioria das fraturas envolveu a camada híbrida e / ou camada adesiva. Ambas as variáveis não preveniram o intenso efeito citotóxico dos sistemas adesivos sobre as células MDPC-23 em cultura, uma vez que redução intensa na viabilidade celular (± 88%) e alterações severas na morfologia celular foram observadas para todos os grupos quando comparados ao NC, sem diferenças entre eles (p > 0.05). Desta forma, foi concluído que a aplicação do SU seguindo o protocolo ER apresentou melhor performance adesiva. No entanto, esse sistema adesivo promoveu intensa citotoxicidade transdentinária sobre células pulpares, independente do protocolo de aplicação e grau de umidade dentinária.

Water sorption and solubility of glass ionomer cements indicated for atraumatic restorative treatment considering the time and the pH of the storage solution / Sorção de água e solubilidade de cimentos de ionômero de vidro indicados para tratamento restaurador atraumático em função do tempo e do pH da solução de armazenagem

ABSTRACT Objective: Evaluate the water sorption and the solubility of glass ionomer cements considering the time and the pH of the storage solution. Methods: The materials used in this survey study were the following ones: Ketac Molar Easymix, Maxxion R, Vitro Molar, Vitremer and Vitro Fil LC. Fifteen specimens of each material were fabricated and subdivided into the storage solutions (deionized water, acid artificial saliva and neutral artificial saliva), having the mass measured in 24 hours, 7, 14 and 21 days. Water sorption and solubility values (µg/mm3) were obtained and submitted to the analysis of variance (ANOVA) and the Tukey test (p <0.05). Results: The water sorption values were statistically different for all the studied materials and solutions in each storage period, except for the Maxxion R. Considering the solubility, all the glass ionomer cements presented values that were not statistically different when evaluating the storage solutions, except for the Vitro Fill LC. Conclusion: The water sorption and the solubility of the studied glass ionomer cements were not influenced by the various storage solutions.

RESUMO Objetivo: Avaliar a sorção de água e a solubilidade de cimentos de ionômero de vidro em função do tempo e do pH da solução de armazenagem. Métodos: Os materiais utilizados foram: Ketac Molar Easymix, Maxxion R, Vitro Molar, Vitremer e Vitro Fil LC. Foram confeccionados 15 espécimes de cada material que foram subdivididos nas soluções de armazenamento (água deionizada, saliva artificial ácida e saliva artificial neutra) e tiveram suas massas mensuradas em 24 horas, 7, 14 e 21 dias. Os valores da sorção de água e solubilidade (µg/mm3) foram obtidos e submetidos à análise de variância (ANOVA) e ao teste de Tukey (p<0,05). Resultados: Os valores de sorção de água diferiram estatisticamente para cada período de armazenamento para todos os materiais e soluções estudadas, exceto para o Maxxion R. Em relação à solubilidade, todos os cimentos de ionômero de vidro apresentaram valores que não diferiram estatisticamente comparando as soluções de armazenamento, exceto o Vitro Fill LC. Conclusão: A sorção de água e a solubilidade dos cimentos de ionômero de vidro estudados não sofreram influência dos diferentes meios de armazenagem.

Bond Strength and Cytotoxicity of a Universal Adhesive According to the Hybridization Strategies to Dentin.

This study evaluated application protocol (etch-and-rinse/ER and self-etching/SE) and dentin wettability (wet and dry) on microtensile bond strength (µTBS) and transdentinal cytotoxicity of ScotchbondTM Universal (SU) adhesive system. The µTBS values and fracture mode were registered 24 h after adhesive system application and resin composite block build-up (n=5). For analysis of transdentinal cytotoxicity, odontoblast-like MDPC-23 cells were seeded on pulpal surface of dentin discs (0.4 mm thick) adapted to artificial pulp chambers (n=8). The adhesive system was applied to occlusal surface, followed by 24-h incubation time. Cell viability (Alamar Blue) and morphology (SEM) were assessed. Adper Single Bond 2 and Clearfil SE Bond were used as positive controls of the ER and SE application protocols, respectively. No treatment was performed on negative control (NC) group. Data were analyzed by ANOVA and Tukey's tests (α=5%). Higher µTBS values were found for ER mode in comparison with SE protocol (p<0.05). Dentin wettability had no effect on bond strength of SU in both the ER and SE techniques (p>0.05). Most fractures involved hybrid layer and/or adhesive layer. Neither variable prevented the intense toxic effects of adhesive systems on MDPC-23 cultured cells, since intense reduction in cell viability (±88%) and severe alterations in cell morphology were observed for all groups compared to NC, with no differences among them (p>0.05). Therefore, it was concluded that application of SU following the ER protocol had better adhesive performance. However, this adhesive system featured intense transdentinal cytotoxicity to pulp cells, regardless of application protocol and dentin wettability.

Avaliação da rugosidade superficial e análise morfológica de cimentos de ionômero de vidro: influência do armazenamento em saliva artificial / Evaluation of surface roughness and morphological analysis of glass ionomer cements: influence of storage in artificial saliva

Introdução: O desenvolvimento dos cimentos de ionômero de vidro (CIVs) proporcionou vantagens aos procedimentos restauradores diretos devido a suas propriedades, como adesão química à estrutura dentária e liberação de flúor. No entanto, o ambiente bucal pode promover condições capazes de alterar a superfície deste material. Objetivo: Avaliar a rugosidade superficial e a morfologia de superfície de quatro cimentos de ionômero de vidro (Ketac Molar Easy Mix, Vitremer, Vitro Molar e Maxxion), quando imersos em diferentes soluções de saliva artificial. Material e método: Dez amostras de cada material foram confeccionadas e a rugosidade superficial foi avaliada antes e após imersão em saliva artificial ácida e neutra, durante 28 dias, por meio de um rugosímetro (Surftest SJ - 40), e a análise morfológica deu-se através de microscopia eletrônica de varredura. Os valores médios de rugosidade foram submetidos aos testes de Kruskal-Wallis e de Wilcoxon, além do teste de Mann Whitney, com nível de significância de 5%. Resultado: Os valores de rugosidade foram maiores estatisticamente após a imersão em saliva ácida e neutra para todos os materiais, exceto o Vitromolar, que não apresentou diferença estatística entre as médias de rugosidade antes e após imersão em saliva neutra. O Maxxion R apresentou estatisticamente maiores valores de rugosidade quando comparado aos outros materiais após imersão em saliva neutra e ácida. Conclusão: A rugosidade superficial dos cimentos de ionômero de vidro aumentou após imersão em saliva neutra e ácida para a maioria dos cimentos estudados. A solução de armazenagem ácida promoveu aumento da rugosidade superficial para o Maxxion R e o Vitro Molar.

Introducion: The development of glass ionomer cements brought advantages to direct restorative procedures due to properties such as chemical adhesion to dental structure and fluoride release. Nevertheless, oral environment may provide conditions which can alter material surface. Objective: To evaluate surface roughness and surface morphology of four glass ionomer cements (Ketac Molar Easy Mix, Vitremer, Vitro Molar e Maxxion) when immersing on different artificial saliva. Material and method: Ten specimens of each material were fabricated and surface roughness was measured before and after immersion on neutral and acid artificial saliva for 28 days using a rugosimeter (Surftest SJ–40) and microscopy analysis by scanning electron microscopy. Roughness data were analyzed statistically by Kruskal-Wallis test, Wilcoxon test and Mann Whitney test, at 5% significance level. Result: Roughness values were statistically higher after immersion on neutral and acid artificial saliva for all materials, except for Vitromolar that did not presented no statistical difference between roughness values before and after immersion on neutral saliva. The Maxxion R presented statistically higher roughness values compared to all materials after immersion on neutral and acid artificial saliva. Conclusion: The superficial roughness of glass ionomer cement increased after immersion on neutral and acid artificial saliva for most of the materials. Acid storage solution promoted a greater increase in surface roughness after immersion of the specimens for Maxxion and Vitro Molar.

Resistência de união de compósitos do tipo Bulk Fill: análise in vitro / Microtensile bond streght of Bulk Fill resin composites: in vitro analysis

Introdução: A classe dos compósitos Bulk-Fill tem obtido popularidade com a promessa de ser fotopolimerizado efetivamente em camadas de até quatro milímetros, fato que contrasta com os dois milímetros requisitados para os compósitos convencionais para manutenção da adesividade da restauração. Objetivo: O objetivo deste estudo foi analisar a resistência de união à dentina de restaurações confeccionadas com compósitos do tipo Bulk-Fill. Material e método: Foram utilizados 15 terceiros molares humanos, cuja superfície oclusal foi cortada e a dentina foi exposta. Esses elementos dentários foram divididos em três grupos conforme o material restaurador utilizado. O sistema adesivo usado foi o mesmo para todos os grupos. Posteriormente, os dentes restaurados foram cortados para originar palitos de aproximadamente 1 mm de largura, 1 mm de profundidade e 8 mm de altura, que foram fixados às garras do dispositivo de microtração. Foram utilizados dez palitos de cada dente, totalizando 50 palitos por grupo. Os dados de resistência de união à microtração foram expressos em megapascal (MPa). As fraturas foram analisadas em microscópio óptico. Os dados foram analisados através dos testes ANOVA e Tukey (p<0,05). Resultado: Os três compósitos estudados diferiram estatisticamente entre si (p<0,000). Os compósitos Bulk-Fill apresentaram resistências de união semelhantes e superiores ao convencional (p<0,000). A fratura mais encontrada foi a mista, em todos os grupos. Conclusão: Os compósitos Bulk-Fill apresentaram maiores valores de resistência de união com a técnica restauradora utilizada.

Introduction: The class of the Bulk Fill composites has gotten popularity with the promise of been cured effectively of layers up to 4 mm, a fact with contrasts with the 2 mm required for the convencional composites for maintance of the restoration’s adhesion. Objective: The aim of this study was evaluate the microtensile bond strength to dentine of restorations made with Bulk Fill composites. Material and method: 15 thirds molars teeth were utilized, whose occlusal layer was cut, exposing the teeth dentine. The teeth were divided in three groups according to the type of restoration materials. All groups were treated with the adhesive system Adper Single Bond 2. Subsequently they were cut in sticks with approximately 1 mm wide, 1 mm depth and 8 mm high, that were fixated at a universal microtensile maching. 10 sticks of each tooth were used in the experiment totaling 50 sticks per group. The data of bond strength microtensile were expressed in MPa. The failures mode was evaluated at an optical microscope. The Data were statistically analyzed through ANOVA and Tukey test (p<0.05). Result: The three composites studied differed statistically among themselves (p<0.000). The Bulk Fill composites had microtensile bond strength similar and higher than the convencional (p<0.000). The pattern failure mode found in all groups studied was the mixed. Conclusion: The Bulk Fill composites showed the highest values of microtensile bond strength with the restorative technique used.

Avaliação do Nível de Conhecimento de Docentes, Discentes e Leigos Sobre Utilização de Dentes Extraídos e Banco de Dentes Humanos / Evaluation of Awareness Level of Professors, Students and Lay People About Human Teeth Bank Functions and Purposes

Objetivo: Avaliar o nível de conhecimento de docentes e de discentes do Curso de Odontologia e de leigos sobre utilização de dentes extraídos e Banco de Dentes Humanos. Material e Métodos: Foi realizado um estudo observacional e prospectivo. A amostragem foi de 50 indivíduos para discentes e leigos e de 32 docentes. Os critérios de inclusão do estudo foram alunos de graduação de odontologia do 1° ao 10º período, docentes do curso de Odontologia da Universidade Federal da Paraíba e pessoas da população em geral, que estavam nas dependências da Universidade. Os critérios de exclusão foram indivíduos vinculados de alguma forma ao Banco de Dentes Humanos da Universidade Federal da Paraíba. Os dados foram coletados através de questionários e submetidos à análise estatística descritiva. Resultados: Entre os leigos, 88% foram a favor da doação de órgãos, porém 80% não representavam "doadores de órgãos". No que se refere ao conhecimento sobre o Banco de Dentes, 86% não sabiam da existência dele, porém 84% doariam seu dente extraído. Para 84% dos acadêmicos entrevistados, já havia sido solicitados dentes para uso laboratorial ou para pesquisa. Os dentes, por eles usados, foram obtidos através de diferentes meios, entre eles o BDH. Em relação aos docentes, 53,1% já solicitaram aos alunos dentes naturais para uso laboratorial ou para pesquisa na graduação. Conclusão: A desinformação dos leigos sobre a existência de Bancos de Dentes foi alta. Dentes extraídos foram solicitados na graduação para realizar atividades acadêmicas. Todos os discentes e os docentes consideraram importante a existência do Banco de Dentes para dar suporte ao ensino e à pesquisa. (AU)

Objective: To evaluate the awareness level of dental professors and students, and of lay people, about Human Teeth Bank (HTB) existence and operation, functions and purposes. Materials and Methods: A descriptive and prospective study was conducted, with a sample size of 50 students, 50 lay people, and 32 professors. The inclusion criteria for the study were: undergraduate dental students from the 1st to the 10th semester, dental professors at Federal University of Paraiba, and people from the general population who were at the university. The exclusion criteria were individuals linked somehow to the Human Teeth Bank of the Federal University of Paraiba. The data were collected using questionnaires and analyzed by descriptive statistics. Results: Most lay people reported to be in favor of organ donation (88%), but most of them (80%) were not "organ donors". Eighty-six percent did not know about the existence of the Teeth Bank, but 84% of them would donate his or her extracted teeth. Among the students, 84% had already been requested to provide natural teeth for laboratory use or for research purposes. The teeth were obtained through different means, including the HTB. As for professors, the majority (53.1%) had already requested natural teeth from their students for laboratory use or for graduate research purposes. Conclusions: The lack of knowledge about the existence of the Teeth Bank was found to be high among the lay people. At the undergraduate level, extracted teeth are frequently requested for the conduction of experimental studies and other academic activities. All students and professors considered the Teeth Bank important to support academic and research activities. (AU)

Influência da dieta líquida infantil na rugosidade do esmalte de dentes bovinos / Diet children's influence in net roughness of cattle teeth enamel

Objetivo: Avaliar a rugosidade do esmalte de dentes bovinos submetidos ao desafio erosivo por bebidas infantis, no intervalo de tempo de 07, 14 e 21 dias e a influência de dentifrício fluoretado após esses desafios erosivos. Métodos: Foram obtidos 40 espécimes de bloco de esmalte, os quais foram divididos aleatoriamente em 8 grupos de acordo com os tratamentos (n=5): G1 ­ suco de maçã Ades®; G1F ­ suco de maçã Ades® + dentifrício; G2 ­ mel de abelha Yoki®; G2F ­ mel de abelha Yoki® + dentifrício; G3 ­ leite fermentado Chamyto®; G3F ­ leite fermentado Chamyto® + dentifrício; G4 ­ controle; G4F ­ controle + dentifrício. Após a análise da rugosidade superficial inicial, os blocos de esmalte foram submetidos ao desafio erosivo. Para os grupos com tratamento com flúor, os espécimes foram imersos em dentifrício fluoretado diluído. Foram realizadas análises da rugosidade superficial após os períodos de 7, 14 e 21 dias. Os dados foram submetidos à análise estatística, empregando-se os testes de Friedman e Wilcoxon com 5% de probabilidade. Resultados: O grupo G2F e G2 apresentaram valores de rugosidade de superfície estatisticamente superiores (p=0,01) após 7 e 21 dias, respectivamente, em relação ao valores iniciais. Os valores de rugosidade de superfície para o grupo G3 (p=0,006) e G3F (p=0,01) foram superiores estatisticamente após 7 dias em relação ao período inicial. Conclusão: Os valores de rugosidade do esmalte aumentaram após o desafio erosivo com mel de abelha e o leite fermentado. O uso do dentifrício fluoretado não promoveu menor incremento de rugosidade.(AU)

Aim: To evaluate surface roughness of tooth enamel when submitted to erosive challenge from beverages after 07, 14 and 21 days as well as the influence of fluoride toothpaste on enamel surface roughness after the erosive challenges. Methods: Forty enamel blocks were made and divided into 8 groups according to treatment (n=5): G1 ­ apple juice Ades ®; G1F ­ apple juice Ades ® + fluoride toothpaste; G2 ­ honey; G2F ­ honey + fluoride toothpaste; G3 ­ fermented milk Chamyto ®; G3F ­ fermented milk Chamyto ® + fluoride toothpaste ; G4 ­ control; G4F ­ control + fluoride toothpaste. After initial analysis of surface roughness, specimens were submitted to erosive challenges. In the groups submitted to fluoride treatment, specimens were immersed in diluted fluoride toothpaste. Analysis of surface roughness was conducted after 7, 14 and 21 days. The values of average enamel roughness (Ra) in the experimental groups were submitted to Friedman and Wilcoxon test considering the significance level of 5%. Results: The G2 and G2F group presented statistically higher roughness values (p=0,01) compared to baseline, after 21 and 7 days, respectively. For G3 (p=0,006) and G3F group (p=0,01), roughness values were statistically higher after 7 days compared baseline. Conclusion: Enamel roughness values increased after erosive challenge with honey and fermented milk. Application of fluoride toothpaste did not promote lower roughness values.(AU)

Influência da aplicação tópica de géis de flúor na rugosidade superficial de cimentos de ionômero / Influence of topical applications of fluoride of gels of the surface roughness of glass ionomer cements

Avaliar a morfologia de superfície de quatro CIVs (cimentos de ionômero de vidro) quando submetidos à ação tópica do flúor fosfato acidulado a 1,23% e gel de fluoreto de sódio neutro a 2%. Foram confeccionados 10 espécimes de cada CIVs (Ketac Molar Easymix, Maxxion R, Vitro Molar e Vitremer). Um ensaio de rugosidade foi efetuado antes e após aplicação tópica de gel de flúor. Os dados obtidos foram analisados através do teste de Tukey e do teste T. Os valores de rugosidade apresentados pelos materiais, segui a ordem descrescente: Maxxion>Ketac Molar Easy Mix> Vitro Molar. A aplicação tópica de flúor acidulado apresentou alterações de superfície nos materiais avaliados.

To evaluate the surface morphology of four glass ionomer cements when submitted to 1.23% acidulated phosphate fluoride topical application and 2% sodium fluoride. Ten specimens of each material (Ketac Molar Easymix, Maxxion R, Vitro Molar and Vitremer) were made. Surface roughness testing was made before and after topical application of fluoride. Data were analyzed statistically by Tukey’s test and T´s test. Maxxion presented the biggest variation on morphological standard after treatment with acidulated gel, continuing, in decreasing order, by Ketac Molar Easy Mix and Vitromolar. The topical acidulated fluoride presented surface alterations in all evaluated materials.