Longitudinal bond strength of a universal adhesive and chemical dentin characterization under different acid etching protocols

Abstract Objective This study aimed to analyze the longitudinal bond strength of a universal adhesive and chemically characterize the dentin substrate under different acid etching protocols. Methodology Dentin samples were etched with polyacrylic acid 25% (PAA) for 10 seconds (n=3) and phosphoric acid 32% (PA) for 15 seconds (n=3) and analyzed by Fourier transform infrared spectroscopy - attenuated total reflectance (FTIR-ATR) before and after treatment. For collagen degradation, samples (n=12) were divided into 3 groups: PAA, PA, and Deionized water (control), and analyzed by the quantity of solubilized type I collagen C-terminal cross-linked telopeptides and solubilized C-terminal peptide in relation to total protein concentration (ICTPtp and CTXtp) and by their ultimate tensile strength (UTS). For the adhesive interface analysis, dentin samples (n=72) were divided into 3 groups: PAA, PA, and Self-etch (SE), and subdivided into 2 groups: 24 h (baseline) and 1 year. The following tests were performed: microtensile bond strength (μTBS) (n=48), scanning electron microscopy (SEM) (n=12), and nanoleakage (n=12). Results The FTIR of PAA showed lower reduction of the peaks in the phosphate group when compared to PA. For ICTPtp, PA showed a significantly higher value. For CTXtp, PA and PAA groups failed to statically differ from each other. UTS was significantly lower for PA. For μTBS, storage time significantly affected bond strength. The results were unaffected by the etching protocol. For SEM, after 1 year, PA had little evidence of degradation in the upper third of the adhesive interface in comparison to the other groups. Nanoleakage showed no considerable silver impregnation after 1 year in the SE group. Conclusion The use of PAA prior to a universal adhesive (when compared to PA) represents a less aggressive type of etching to dentin. However, self-etching still seems to be the best option for universal adhesive systems that have functional monomers in their composition.

Mecanismos preventivos de la degradación de la capa híbrida / Preventive mechanisms of the degradation of the hybrid layer

Uno de los mayores retos de la odontología actual es lograr una adhesión duradera y estable entre los materiales de restauración y los tejidos dentales. Los protocolos adhesivos han ido cambiando a lo largo del tiempo para cumplir con dicho objetivo, tratando de mantener la integridad de la capa hibrida, por lo que se revisaron los factores que provocan la degradación de la capa hibrida y los mecanismos propuestos para prevenir esta degradación. Se realizó una investigación y recopilación de información bibliográfica especializadas en el tema, en buscadores científicos como PubMed, Scielo, Redalyc, Medigraphic y Scopus. Para los criterios de inclusión se consideraron años de publicación entre el año 2002 al 2022, enfocados en trabajos de investigación relacionados con la degradación de la interfaz de unión resina-dentina y mecanismos para prevenir esta degradación en la capa híbrida. El mecanismo mas estudiado a corto y largo plazo es la aplicación de clorhexidina, la cual se utiliza después del ácido fosfórico y antes del adhesivo, inhibe la actividad proteolítica de las metaloproteinasas de la matriz (MMPs) y retarda la degradación de las fibras colágenas, consiguiendo de esta manera una mayor vida de las restauraciones adhesivas.

One of the biggest challenges in dentistry is to achieve a long-lasting and stable bond between restorative materials and dental tissues. The adhesive protocols have been changing over time to meet this objective, trying to maintain the integrity of the hybrid layer, so the factors that cause the degradation of the hybrid layer and the mechanisms proposed to prevent this degradation were reviewed. An investigation and compilation of specialized bibliographic information on the subject was carried out, in scientific search engines such as PubMed, Scielo, Redalyc, Medigraphic, Scopus, among others, as well as books. For the inclusion criteria, years of publication between 2002 and 2022 were considered, focused on research works related to the degradation of the resin-dentin bonding interface and mechanisms to prevent this degradation in the hybrid layer. The placement of CHX is used after the application of phosphoric acid and before the adhesive, it inhibits the proteolytic activity of matrix metalloproteinases (MMPs) and the degradation of collagen fibers, thus achieving a longer life of resin dental restorations.

Bond strength of composite resin/universal adhesive to dentin submitted to radiotherapy / Fuerza de unión de resina compuesta/adhesivo universal a dentina sometida a radioterapia

Aim: To evaluate the bond strength of a universal adhesive system to dentin submitted to radiotherapy. Materials and Methods: Sixty extracted human teeth were divided into two groups (n = 30): without radiotherapy (control); with radiotherapy, according to the adhesive protocol (n=15): ER-etch-and-rinse (acid + Single Bond Uni-versal); SE-self-etch (Single Bond Universal). The analyzes were shear bond strength (SBS) (n=10), failure pattern (n=10) and scanning electron microscopy (n=5). Data was analyzed by a two-way ANOVA (α =0.05). Results: The radiotherapy decreased SBS of the restorative material to dentin (p<0.0001). The ER protocol provided lower bond strength values (p<0.001). The predominant type of fracture without radiotherapy was mixed (SE), cohesive to the material (ER). Both protocols presented adhesive failures with radiotherapy. Teeth had a hybrid layer and long resin tags (without radiotherapy) and few tags (with radiotherapy). Conclusions: The SE adhesive mode favors the shear bond strength of resin to dentin in teeth submitted to radiotherapy.

Objetivo: Evaluar la fuerza de adhesión de un sistema adhesivo universal a la dentina sometida a radioterapia. Materiales y Métodos: Sesenta dientes humanos extraídos se dividieron en dos grupos (n = 30): sin radioterapia (control); con radioterapia, según protocolo adhesivo (n=15): ER-grabado y enjuague (ácido + Single Bond Universal); autograbado SE (Single Bond Universal). Los análisis ejecutados fueron resistencia al cizallamiento (SBS) (n=10), patrón de falla (n=10) y microscopía electrónica de barrido (n=5). Los datos se sometieron al test de ANOVA de dos vías (α =0,05). Resultados: La radioterapia disminuyó la SBS del material restaurador a la dentina (p<0,0001). El protocolo ER proporcionó valores de fuerza de unión más bajos (p<0,001). El tipo de fractura predominante sin radioterapia fue mixta (SE), cohesiva al material (ER). Ambos protocolos presentaron fallas adhesivas con radioterapia. Los dientes tenían una capa híbrida y colas de resina largas (sin radioterapia) o pocas colas de resina (con radioterapia). Conclusión: El modo adhesivo SE favorece la resistencia al corte de la resina a la dentina en dientes sometidos a radioterapia.

Evaluation of the efficacy and safety of endoscopic injection of polidocanol combined with low-dose tissue glue occlusion in the treatment of F3 type esophageal varices in liver cirrhosis / 中国医师杂志

Objective:To explore the efficacy and safety of endoscopic injection of polidocanol combined with low-dose tissue glue occlusion in the treatment of F3 esophageal varices in liver cirrhosis.Methods:Retrospective analysis was made on 42 patients with cirrhosis type F3 esophageal varices admitted to the Affiliated Hospital of Zunyi Medical University from January 2020 to June 2021. According to different treatment methods, they were divided into the observation group and the control group, with 21 cases in each group. The observation group received endoscopic injection of polidocanol combined with low-dose tissue glue occlusion, while the control group received endoscopic injection of polidocanol. The differences in the effectiveness (remission rate of varices) and safety (incidence of intraoperative bleeding and postoperative rebleeding, incidence of ectopic embolism, incidence of esophageal ulcer, incidence of esophageal perforation, incidence of esophageal stricture) of the two groups of patients were compared.Results:The total effective rate of relieving esophageal varices in the observation group was significantly better than that in the control group [95.2%(20/21) vs 61.9%(13/21), χ 2=6.929, P=0.008]. There were no cases of ectopic embolism in both groups; The intraoperative bleeding rate in the observation group was 4.8% (1/21), significantly lower than the 38.1% (8/21) in the control group (χ 2=6.929, P=0.008); There was no statistically significant difference in postoperative rebleeding rates between the two groups [33.3%(7/21) vs 23.8%(5/21), χ 2=0.467, P=0.495]; The incidence of esophageal ulcers in the observation group was higher than that in the control group [23.8%(5/21) vs 0, χ 2=5.676, P=0.017], mainly caused by glue discharge ulcers; There were no cases of esophageal perforation and esophageal stricture in both groups. Conclusions:Endoscopic injection of polidocanol combined with low-dose tissue glue occlusion for the treatment of F3 esophageal varices in liver cirrhosis is safe, can greatly reduce the occurrence of intraoperative bleeding, and has a better one-time variceal eradication effect.

Evaluation of short- and long-term bond strength of zirconia after different surface treatments / Avaliação da resistência de adesão de curto e longo prazo de zircônia após diferentes tratamentos de superfície

Objective: The aim of the study was to evaluate the short and long-term effects of different surface treatments on the bond strengths of zirconia. Material and Methods: 225 blocks of sintered zirconia samples (4 x 4 x 3 mm) were divided into five groups and subjected to different surface treatments: control group (without surface treatment), alumina group (sandblasting [25-µm-aluminum-oxide]), alumina+Ambar Universal-APS (AU) group, CoJet group (silica-coated [30-µm silica-modified aluminum particles]), and CoJet+AU group. Subsequently, zirconia samples were cemented against resin samples (total dimensions: 8x8x6mm) and assigned to three storage conditions: dry, humid (artificial saliva at 37°C for 30-days) or thermocycling [100.000-cycles] (n=15 per group). The microtensile bond strength (µTBS) was determined using a universal testing machine. The failure modes were observed and analyzed using a stereomicroscope. Normality tests, descriptive statistics, and two-way ANOVA, followed by post-hoc comparisons, were performed to evaluate the effect of surface treatments and storage conditions on µTBS (α=0.05). Results: µTBS was influenced by surface treatment in the short and long-term (P<0.0001). The highest values were found in CoJet+AU in dry (33.51 ±2.48 MPa), humid (32.87 ±2.68 MPa) and thermocycling (21.37 ±1.68 MPa) storage conditions compared with others. Interestingly, no significant differences in µTBS were found among alum +AU and CoJet alone under any of the three storage conditions. Adhesive failure increased in all groups after thermocycling, but CoJet+AU had the lowest values of adhesive failure compared with others. Conclusion: The combination of CoJet and Ambar universal as a surface treatment for zirconia specimens provides significantly higher short and long-term bond strengths of adhesive cementation (AU)

Objetivo: O objetivo do estudo foi avaliar os efeitos de curto e longo prazo de diferentes tratamentos de superfície na resistência de adesão da zircônia. Material e Métodos: 225 blocos de amostras de zircônia sinterizada (4 x 4 x 3 mm) foram divididos em cinco grupos e submetidos a diferentes tratamentos de superfície: grupo controle (sem tratamento de superfície), grupo de alumina (jateamento de 25 µm de óxido de alumínio), grupo alumina+Ambar Universal-APS (AU), grupo CoJet (partículas de alumínio modificadas por sílica de 30 µm), e grupo CoJet+AU. Posteriormente, as amostras de zircônia foram cimentadas em amostras de resina (dimensões totais: 8x8x6mm) e designadas para três condições de armazenamento: seco, úmido (saliva artificial a 37°C por 30 dias) ou ciclagem térmica (100.000 ciclos) (n=15 por grupo). A resistência de adesão de microtensão (µTBS) foi determinada usando uma máquina de teste universal. Os modos de falha foram observados e analisados usando um estereomicroscópio. Testes de normalidade, estatísticas descritivas e ANOVA de duas vias, seguidas de comparações pos-hoc, foram realizados para avaliar o efeito dos tratamentos de superfície e das condições de armazenamento na µTBS (α=0.05). Resultados: A µTBS foi influenciada pelo tratamento de superfície a curto e longo prazo (P<0.0001). Os valores mais altos foram encontrados em CoJet+AU nas condições de armazenamento a seco (33.51 ±2.48 MPa), úmido (32.87 ±2.68 MPa) e ciclagem térmica (21.37 ±1.68 MPa) em comparação com os outros. Curiosamente, não foram encontradas diferenças significativas na µTBS entre alum +AU e CoJet sozinho em nenhuma das três condições de armazenamento. A falha adesiva aumentou em todos os grupos após a ciclagem térmica, mas CoJet+AU teve os valores mais baixos de falha adesiva em comparação com os outros. Conclusão: A combinação de CoJet e Ambar Universal como tratamento de superfície para espécimes de zircônia proporciona resistências de adesão significativamente mais altas a curto e longo prazo para cimentação adesiva. (AU)

Can composite packaging and selective enamel etching affect the clinical behavior of bulk-fill composite resin in posterior restorations? 24-month results of a randomized clinical trial

Abstract Objectives This is a double-blind, split-mouth, randomized clinical study that aims to evaluate the influence of bulk-fill composite packaging presented in syringes (BSy) and capsules (BCa), and the effect of selective enamel etching (SEE) on the clinical performance of class I and II bulk-fill resin composite restorations after 24 months. Methodology A total of 295 class I or class II restorations were performed on 70 patients. One universal adhesive was applied in all restorations. SEE was used in 148 restorations and self-etching mode (SET) in 147 restorations. After the adhesive application, cavities were restored with Filtek Bulk-fill Posterior Restorative in syringes (BSy), Filtek One Bulk-fill in capsules (BCa), or Filtek Supreme Ultra in syringes with the incremental technique (In). All restorations were evaluated using the FDI criteria after one week and after six, 12, and 24 months. Kaplan-Meier survival analysis and Pearson's Chi-square test were used (α=0.05) for statistical analysis. Results After 24 months, 62 patients were evaluated and four restorations were lost due to fracture (one for SEEBSy, two for SEEIn, and one for SETIn). No significant differences in the fracture and retention rate were found between groups (p>0.05). SEE showed significantly fewer marginal adaptation defects than SET (p<0.05). BCa and BSy groups showed fewer marginal discrepancies compared to In (p<0.05). Restorations performed with BCa showed less color mismatch than BSy or In (p<0.05). Conclusion Although all restorations exhibited satisfactory clinical performance after 24 months of clinical service, the clinical behavior of class I and II restorations' improved when performed with a bulk-fill composite in capsules, mainly when associated with a universal adhesive applied with SEE.

Is the adhesive or mechanical behavior of glass ceramics influenced by the adhesive layer application after etching and silanization? A literature review

Aim: This review investigated the effect of applying an adhesive after surface treatment of glass-ceramics on the bonding, mechanical or clinical behavior. Methods: Studies comparing the adhesive, mechanical or clinical behavior of glass-ceramics, with or without adhesive application after surface treatment, were included. Searches were performed in PubMed, Scopus, and Web of Sciences databases (January 2022), resulting in 15 included studies. Results: Regarding the evaluated outcomes, 13 studies assessed bond strength, 2 studies assessed biaxial flexural strength and 1 study assessed fatigue failure load, while no study evaluating clinical outcomes was included. It was possible to observe that the adhesive application after ceramic surface treatment was unfavorable or did not influence the evaluated outcomes. Conclusion: Most of the evidence available in the literature shows that the adhesive application after surface treatment does not improve the adhesive and mechanical behavior of glass-ceramics

Influence of the combined effect of desensitizing dentifrices and universal adhesives on dentin bond strength under erosive conditions

Abstract Objective This study aimed to evaluate whether the use of desensitizing dentifrices containing obliterating agents can affect bond strength of eroded/abraded dentin. Methodology A total of 100 dentin samples were obtained from human molars. The teeth were cut into 3 mm-thickness discs and allocated in five groups (n=20), according to the toothpaste used: WoF - abrasion with fluoride-free toothpaste (Cocoricó); Arg - toothpaste containing arginine (Colgate Sensitive Pro-Relief); Nov - calcium sodium phosphosilicate toothpaste (Sensodyne Repair and Protect); SnF - fluoride-containing toothpaste (AmF/SnCl2/SnF2 - Elmex Erosion); and Control (no erosive/abrasive process). The erosive/abrasive cycle consisted of immersion in citric acid (1%, pH 2.6, 5 min, 4×/day) and abrasion (2×/day, 120-20 sec abrasion, 100 sec immersion) with each toothpaste. During intervals, samples were immersed in artificial saliva. This cycle was performed for five days. Two resin cylinders (2 mm in diameter) were constructed on each sample for the shear bond strength test using a universal adhesive system. The self-etch and etch-and-rinse (Scotchbond Universal) strategies were employed, each in half of the total sample (n=10). Bond strength (MPa) was measured in a shear test and failure modes were assessed with a stereomicroscope. Statistical analysis was performed using the two-way analysis of variance (ANOVA) and Tukey tests (p<0.05). Results A statistically significant difference was found between the adhesive strategies tested (p<0.001), with the self-etching form showing higher values than the etch-and-rinse. Moreover, no significant differences were observed between the tested toothpastes (p=0.750) and interactions (p=0.438). Conclusion The use of toothpaste containing obliterating agents does not affect bond strength to dentin subjected to erosive/abrasive conditions when a universal adhesive is used. However, the self-etch strategy might be preferred for eroded/abraded dentin.

Efecto del pretratamiento con clorhexidina en la resistencia de unión a dentina desmineralizada

Objetivo: Analizar la resistencia de unión a dentina sana y desmineralizada, en forma inmediata y a los 6 meses, utilizando un pretratamiento de clorhexidina (CHX) 2%. Método: 40 terceros molares sanos con desarrollo radicular incompleto se desgastaron exponiendo dentina. Las piezas fueron sometidas a ciclado de pH. Se dividieron aleatoriamente en 2 grupos: con y sin CHX. En dentina se crearon 4 botones de resina utilizando adhesivo universal mediante autoacondicionamiento. Las muestras se almacenaron en agua destilada a 37ºC hasta su análisis. El microcizallamiento se ejecutó a las 24 horas y a los 6 meses de envejecimiento. Resultados: El grupo de dentina sana, sin CHX inmediato presentó mayor resistencia adhesiva (23,37±1,84). El grupo de dentina desmineralizada, sin CHX, envejecido presentó la menor resistencia adhesiva (8,87±1,51). Conclusiones: La CHX al 2% previo a la aplicación del adhesivo no mejora los valores de resistencia de unión a dentina sana ni desmineralizada a corto o largo plazo.

Objetivo: Analisar a resistência de união à dentina hígida e desmineralizada, imediatamente e após 6 meses, utilizando um pré-tratamento com (CHX) a 2%. Método: 40 terceiros molares hígidos com desenvolvimento radicular incompleto foram desgastados expondo a dentina. As peças foram submetidas a ciclagem de pH. Eles foram divididos aleatoriamente em 2 grupos: com e sem CHX. Em dentina, foram criados 4 botões de resina utilizando adesivo universal em modo autocondicionante. As amostras foram armazenadas em água destilada a 37ºC até a análise. O microcisalhamento foi realizado às 24 horas e aos 6 meses de envelhecimento. Resultados: O grupo de dentina saudável, sem CHX imediata apresentou maior resistência adesiva (23,37±1,84). O grupo de dentina desmineralizada, sem CHX , envelhecida apresentou a menor resistência adesiva (8,87±1,51). Conclusões : A CHX antes da aplicação do adesivo não melhoraria os valores de resistência de união em dentina saudável ou desmineralizada a curto ou longo prazo.

Objective: To analyze the bond strength to healthy and demineralized dentin, immediately and after 6 months, using a 2% chlorhexidine (CHX) pretreatment. Method : 40 healthy third molars with incomplete root development were abraded exposing dentin. The pieces were subjected to pH cycling. They were randomly divided into 2 groups: with and without CHX. In dentin, 4 resin buttons were created using universal adhesive in self-etching mode. The samples were stored in distilled water at 37ºC until analysis. Micro shearing was carried out at 24 hours and at 6 months of aging. Results: Healthy dentin group, without immediate CHX presented higher bond strength (23.37±1.84). (Demineralized dentin group, without CHX, aged) presented the lowest bond strength (8.87±1.51). Conclusions : CHX prior to adhesive application doesn't improve bond strength values to healthy or demineralized dentin in short nor long term.

Influence of bioceramic intracanal medication on the bond strength of bioceramic root canal sealer

Abstract To investigate the influence of the remaining volume of a new intracanal medication based on bioceramic compounds on the bond strength (BS) and formation of an adhesive interface between calcium silicate-based and epoxy resin-based root canal sealers. For this purpose, the specimens were distributed according to the intracanal medication (n = 26): Bio-C Temp (BCT) and Ultracal XS (UXS). The roots were scanned in microCT, and after 7 days, the medication was removed. Then a new scan was performed to evaluate the volume of medication remaining. Subsequently, 40 specimens were redistributed into 2 subgroups (n = 10) and filled according to the sealer used: AH Plus (AHP) and Bio-C Sealer (BCS), to assess the bond strength by using the push-out test, and the adhesive interface by confocal laser fluorescence microscopy (CLSM) and scanning electron microscopy (SEM). The t test showed a smaller remainder of BCT (1.77 ± 0.86) compared with UXS (10.47 ± 5.78), irrespective of the root third evaluated. The BS showed that teeth with BCT + BCS had higher bond strength values (3.70 ± 1.22) when compared to the other groups: BCT + AHP (2.15 ± 1.07), UXS + BCS (3.18 ± 1.09) and UXS + AHP (2.11 ± 1.02) (p<0.001). The cervical third had higher BS when compared with the middle and apical thirds (p < 0.001), and higher number of adhesive failures. The adhesive interface in SEM and CLSM images showed better adaptation for the association between BCT + BCS. Intracanal medication and silicate-based endodontic sealer appeared to interact chemically by forming a biomineralizing layer, allowing for an increase in the bond strength and forming an adhesive interface between the materials, with no or less gap formation.

Resistencia de cerámicas de disilicato de litio adheridas con dos adhesivos diferentes

Introducción: la cerámica de disilicato de litio es una excelente opción en rehabilitación, confeccionado con la técnica de inyección o maquinadas. El objetivo de este estudio fue evaluar la influencia de dos sistemas adhesivos sobre los valores de resistencia de unión en cerámicas de disilicato de litio inyectado y maquinado. Métodos: se utilizó discos de disilicato de litio, IPS e. Max CAD (Ivoclar Vivadent, Liechtenstein, Swiss), de 10mm de diámetro y 1mm de espesor embebidos en tubos de PVC. Se distribuyó en 4 grupos de trabajo, 2 en cerámica de litio inyectadas y 2 en maquinada, se aplicaron los adhesivos Palfique Bond y Tetric N-bond Universal según la distribución de grupos, luego se fotopolimerizó durante 10 segundos con lámpara luz led, se colocaron los tubos Tygon® para el relleno con resina fluida; una vez retirado los tubos Tygon®, se llevaron las muestras a una máquina de ensayo universal donde se realizó la prueba de micro cizallamiento. Resultados: los valores de resistencia de unión más significativos fueron encontrados en las cerámicas de disilicato de litio adherida con el adhesivo Palfique Bond y Tetric Bond teniendo una diferencia significativa (p= 0.001), los valores de resistencia de unión del adhesivo Palfique Bond y Tetric Bond en cerámica inyectada no tuvieron diferencia significativa. Conclusión: las cerámicas de disilicato de litio maquinadas presentan mejores valores de resistencia de unión al micro cizallamiento.

Introduction: lithium disilicate ceramics are an excellent choice in rehabilitation, made with the technique of injection or machining. The aim of this study was to evaluate the influence of two adhesive systems on the values of binding resistance in injected and machined lithium disilicate ceramics. Methods: lithium disilicate disks, IPS e. were used Max CAD (Ivoclar Vivadent, Liechtenstein, Swiss), 10mm in diameter and 1mm in thickness embedded in PVC tubes. Was distributed in 4 working groups, 2 in injected lithium ceramics and 2 in machined, Palfique Bond and Tetric N-bond Universal adhesives were applied according to the group distribution, then photopolymerized for 10 seconds with led light bulb, Tygon® tubes were placed for filling with fluid resin; once the Tygon® tubes were removed. The samples were taken to a universal testing machine where the micro-spraying test was performed. Results: the most significant binding resistance values were found in lithium disisilicate ceramics adhered with the Palfique Bond and Tetric Bond adhesive having a significant difference (p= 0,001), the bond strength values of the Palfique Bond and Tetric Bond adhesive in injected ceramic did not differ significantly. Conclusion: machined lithium disilicate ceramics have better values of binding resistance to micro-spraying.

Bond strength of two universal adhesive systems to human dentin using different strategies / Resistência de união de sistemas adesivos universais à dentina humana usando diferentes estratégias

ABSTRACT The objective of this study was to evaluate the microtensile bond strength (μTBS) to dentin of two universal adhesive systems: Single Bond Universal (SBU) and Ambar Universal , used in different adhesion strategies. Materials and Method: Thirty-six human teeth were prepared (n=6) and treated following different adhesive strategies: G1: SBU-etch-and-rinse, applied on dry dentin; G2: SBUetch- and-rinse, applied on moist dentin; G3: SBU-self-etching; G4: AU-etch-and-rinse, applied on dry dentin; G5: AU-etch-and-rinse, applied on moist dentin; G6: AU-self-etching. The specimens were submitted to μTBS test, failure analysis, and scanning electron microscopy (SEM). Data were analyzed with ANOVA and Tukey's tests (p<0.05). Results: Microtensile bond strength was significantly lower in G1 than G2 and G3. AU adhesive performed worse than the SBU system, except in G5. Cohesive and mixed failures predominated in G1 and G2, while adhesive failures predominated in G3 and G5. Conclusions: Universal adhesives are an interesting innovation, but there are still doubts about their performance, mainly regarding the different protocols provided by the manufacturers. The conventional adhesive strategy on moist dentin demonstrated higher μTBS for both adhesives. The use of the selfetching strategy with the SBU showed promising results.

RESUMO O objetivo deste estudo foi avaliar a resistência de união à microtração (μTBS) de dois sistemas adesivos universais: Single Bond Universal (SBU) e Ambar Universal , utilizados em diferentes estratégias de adesão. Materiais e método: 36 dentes humanos foram preparados (n=6) e tratados seguindo diferentes estratégias adesivas: G1: SBU-condicionamento e enxágue, aplicado sobre dentina seca; G2: SBU-condicionamento e enxágue, aplicado sobre dentina úmida; G3: SBU-autocondicionante; G4: AU-condicionamento e enxágue, aplicado em dentina seca; G5: AU-condicionamento e enxágue, aplicado sobre dentina úmida; G6: AU-autocondicionante. Os espécimes foram submetidos ao teste de μTBS, análise de falhas e microscopia eletrônica de varredura (SEM). Os dados foram analisados com os testes ANOVA e Tukey (p<0,05). Resultados: A resistência de união à microtração de G1 foi significativamente menor que G2 e G3. O adesivo AU teve um desempenho pior que o sistema SBU, com exceção do G5. Falhas coesivas e mistas predominaram em G1 e G2 enquanto G3 e G5 apresentaram predominância de falhas adesivas. Conclusões: Os adesivos universais representam uma inovação interessante, mas ainda há dúvidas sobre seu desempenho, principalmente em relação aos diferentes protocolos fornecidos pelos fabricantes. A estratégia adesiva convencional em dentina úmida demonstrou maior μTBS para ambos os adesivos. O uso da estratégia autocondicionante com a SBU apresentou resultados promissores.

Short-term effect of adhesive system on clinical performance of bulk fill composite: randomized clinical trial

Aim: Although bulk fill composites have been widely used as restorative material, there is no consensus regarding the best clinical protocol in terms of composite technique and adhesive system. Therefore, this clinical trial evaluated the clinical performance of bulk fill composites for class I restorations under different protocols. Methods: A randomized clinical trial including 155 class I restorations was conducted using different adhesive systems: conventional technique (phosphoric acid + conventional three-step adhesive system) (Group 1, 2 and 3); or self-etching adhesive system (Groups 4, 5 and 6). Control groups 1 and 4 were restored with conventional composite; groups 2 and 5 with low viscosity bulk fill and conventional composite as occlusal coverage; groups 3 and 6 with high viscosity bulk fill. The FDI criteria was used for clinical evaluation at baseline and after 6 months. Results: All groups showed good clinical performance. At baseline, the adhesive system did not affect postoperative hypersensitivity. After 6 months, group 5 showed a significant reduction in color and translucency; group 6 a reduction in terms of anatomical form and for postoperative sensitivity and an improvement in patient satisfaction (p<0.05). Considering the same restorative technique, the use of the self-etching adhesive system showed a significant decrease in color and translucency (p<0.05). Conclusion: All groups showed favorable clinical performance, and promising results were found for the conventional adhesive system and high viscosity bulk fill protocol

Uso efectivo de los adhesivos de octava generación / Effective use of eighth generation adhesives

Introducción: se realizó una revisión bibliográfica con el objetivo de conocer, analizar y comparar los diferentes tipos de adhesivos de octava generación que se encuentran en el mercado y la diferencia que existe entre cada uno. Los adhesivos universales han demostrado mejoras en su resistencia, sobre todo en las técnicas de aplicación y en las propiedades de estos materiales, al mejorar la fuerza adhesiva para que el odontólogo pueda brindar tratamientos restaurativos exitosos. Objetivo: conocer, analizar y comparar los diferentes tipos de adhe- sivos de la octava generación empleados en odontología. Material y métodos: se realizó una búsqueda en las bases de datos electrónicas PubMed, BVS, Redalyc y ScienceDirect. Se utilizaron 32 artículos que cumplieron con los criterios predeterminados y la especificidad reque- rida para la pregunta de investigación. Conclusiones: se demostró que la tecnología cada día avanza, sobre todo en el área de los adhesivos, ya que éstos son de mucha utilidad en el día a día del odontólogo; es importante conocer cada uno de éstos, puesto que es un poco complejo seleccionar el correcto, mas no el uso. En la actualidad, existen diversas opciones por las que el odontólogo puede optar, es por ello que el pro- fesional debe estar capacitado sobre cada una de las diferentes marcas existentes y, de acuerdo al tratamiento, debe elegir cuál es mejor utilizar en una rehabilitación. Es importante para el odontólogo conocer estos materiales, ya que esto lo beneficiará al momento de llevar un plan de tratamiento restaurador (AU)

Introduction: a bibliographic review was carried out to learn about, analyze, and compare the different types of eighth-generation adhesives on the market and the difference between each one. Universal adhesives have demonstrated improvements in their resistance, especially in the application techniques and properties of these materials, improving the adhesive strength so that the dentist can provide successful restorative treatments. Objective: to know, analyze and compare the different types of eighth-generation adhesives used in dentistry. Material and methods: a search was made of the following electronic databases: PubMed, BVS, Redalyc, ScienceDirect. Finally, 32 articles that met the predetermined criteria and the specificity required for the research question were used. Conclusions: it was demonstrated that technology is advancing every day, especially in the area of adhesives since these are very useful in the daily life of the dentist. It is important to know each one of these since it is a little complex at the moment of selecting the correct one, but not the use. Currently, there are several options that the dentist can choose, which is why the professional must be trained on each of the various existing brands and according to the treatment which is the best to use at the time of rehabilitation. The dentist needs to know these materials since they will benefit him/her when carrying out a restorative treatment plan (AU)

Clinical follow-up at 18 months of two bulk fill occlusal composite resins: a double-blind randomized clinical study / Seguimiento clínico a 18 meses de dos resinas compuestas oclusales bulk fill: estudio clínico aleatorio doble ciego

Objetive: To compare the clinical behavior of two types of Bulk Fill composite resins and a nanohybrid resin at 18 months in occlusal restorations. Material and Methods: Three occlusal restorations were performed in each one of the 55 participants. They were randomly distributed into three groups, TN: Tetric-N-Ceram Bulk-Fill, FK: Filtek Bulk-Fill, and Z350: Filtek Z350XT. Adhesive techniques and restorative procedures were performed according to the manufacturer's instructions for each restorative material used. In TN and FK an increment of 4mm was applied, and in Z350 increments of ≤2mm depth were applied. Two calibrated operators evaluated the restorations at baseline and at 18 months using the FDI World Dental Federations system (1: excellent, 2: good, 3: satisfactory, 4: unsatisfactory, 5: poor) for clinical marginal staining (MS) properties, fracture-retention (FR), superficial texture (ST), marginal integrity (MI), postoperative sensitivity (PS) and caries (C). Kruskal-Wallis and Wilcoxon were used to compare the 3 groups at 18 months (5% significance). Results: 38 patients with a total of 114 restorations were assessed, being evaluated with excellent clinical behavior; MI, 78.9% in Z350, 89.51% in TN and 81.6% in FK; ST 73.5% in Z350, 86.8% in TN, and 84.2% in FK; MS 84.2% in Z350, 84.2% in TN, and 91.2% in FK; PS 100% in Z350 and 97.3% in TN and FK; in C and FR, 100% in the 3 groups. There were no significant differences between the three groups (p>0.05). Conclusion: The three resins studied presented a good clinical performance at 18 months without showing significant differences in the clinical properties evaluated.

Objetivo: Comparar el comportamiento clínico a 18 meses en restauraciones oclusales entre dos tipos de resinas compuestas Bulk Fill y una resina nanohíbrida. Material y Métodos: En 55 participantes se realizaron 3 restauraciones oclusales en cada paciente, distribuidas aleatoriamente en 3 grupos, TN: Tetric-N-Ceram Bulk-Fill, FK: Filtek Bulk-Fill y Z350: Filtek Z350XT. Las técnicas adhesivas y procedimientos restauradores fueron realizados según las instrucciones de los fabricantes de cada material restaurador utilizado. En TN y FK se aplicó un incremento de 4mm y en Z350 se aplicó incrementos ≤ 2 mm de profundidad. Dos operadores calibrados evaluaron las restauraciones al baseline y a los 18 meses mediante el sistema FDI World Dental Federations (1: excelente, 2: aceptable, 3: suficiente, 4: insatisfactorio, 5: inaceptable) en las propiedades clínicas de tinción marginal (TM), fractura-retención (FR), textura superficial (TS), integridad marginal (IM), sensibilidad postoperatoria (SP) y caries (C). Se utilizó Kruskal-Wallis y Wilcoxon para la comparación de los 3 grupos a 18 meses (significancia de 5%). Resultados: Se controlaron 38 pacientes con un total de 114 restauraciones, siendo evaluados con comportamiento clínico excelente; IM, 78.9% en Z350, 89.51% en TN y 81.6% en FK; TS 73.5%, en Z350, 86.8% en TN y 84.2% en FK; TM, 84.2% en Z350, 84.2% en TN y 91.2% en FK; SP 100% en Z350 y 97,3% en TN y FK; en C y FR 100% en los 3 grupos. No hubo diferencias significativas entre los 3 grupos (p>0,05). Conclusión: Las 3 resinas estudiadas presentaron un buen desempeño clínico a 18 meses sin mostrar diferencias significativas en las propiedades clínicas evaluadas.

Efectividad del Tysuacril en la estomatitis aftosa / Effectiveness of Tysuacril in aphthous stomatitis

RESUMEN Introducción: el Tisuacryl es un biomaterial empleado en la cirugía general y bucal, así como en el tratamiento de la estomatitis aftosa, considerada un proceso multifactorial y actualmente la enfermedad ulcerosa más común de la cavidad oral. Objetivo: determinar la efectividad del Tisuacryl con respecto a la terapia convencional en el tratamiento de la estomatitis aftosa en Consolación del Sur, Pinar del Río, en el período comprendido entre septiembre 2018 y marzo 2020. Métodos: se realizó un estudio observacional analítico de casos y controles a 90 pacientes con estomatitis aftosa en Consolación del Sur, Pinar del Río, en el período comprendido entre septiembre 2018 y marzo 2020. La información se obtuvo de las historias clínicas individuales de Periodoncia al obtener el consentimiento oral y escrito de los pacientes o sus tutores. Los resultados se obtuvieron por análisis estadístico que incluyó el porciento y la prueba no paramétrica de Cochran Q. Resultados: predominó el sexo femenino y el grupo etario de 10 a 19 años para el 46,7 % en grupo estudio y el 42,2 % en grupo control; la disminución del dolor y la cicatrización iniciaron en el mayor número de pacientes a las 72 horas de tratamiento con Tisuacryl para el 91,1 % y el 55,6 % respectivamente; a los cinco días de aplicación del medicamento la totalidad de ellos estaban asintomáticos y casi todas las aftas bucales cicatrizadas. Conclusiones: las lesiones aftosas en la cavidad bucal evolucionaron satisfactoriamente con la aplicación del Tisuacryl al ser esta una alternativa efectiva de tratamiento en comparación con la terapia convencional.

ABSTRACT Introduction: Tisuacryl is a biomaterial used in general and oral surgery, as well as in the treatment of aphthous stomatitis, considered a multifactorial process and currently the most common ulcerative disease of the oral cavity. Objective: to determine the effectiveness of Tisuacryl with respect to conventional therapy in the treatment of aphthous stomatitis in Consolación del Sur, Pinar del Río, in the period from September 2018 to March 2020. Methods: an analytical observational case-control study was conducted on 90 patients with aphthous stomatitis in Consolación del Sur, Pinar del Río, in the period from September 2018 to March 2020. Information was obtained from individual Periodontics medical records by obtaining oral and written consent from patients or their guardians. Results were obtained by statistical analysis including percent and Cochran Q nonparametric test. Results: female sex and age group from 10 to 19 years old predominated for 46,7 % in the study group and 42,2 % in the control group; the decrease of pain and healing started in most patients 72 hours after treatment with Tisuacryl for 91,1 % and 55,6 % respectively; being five days after application of the drug all of them asymptomatic and almost all the oral aphthae healed. Conclusions: aphthous lesions in the oral cavity evolved satisfactorily with the application of Tisuacryl being an effective treatment alternative in comparison with conventional therapy.

Sistemas Adesivos Universais: um Panorama do Estado da Arte / Universal Adhesive Systems: a State-of-the-art Overview

Adhesive systems play a fundamental role in the adhesion of restorative materials to dental substrates. To make this adhesion more effective and long-lasting, these materials are in constant evolution, seeking to simplify the clinical steps and reduce the technique's sensitivity. The most recent generation of adhesives developed is the universal adhesives, which promise versatility and reduction of clinical steps. The aim of this study was to perform a literature review on universal adhesives and their characteristics. The literature review was performed by means of an electronic search in the Pubmed database. The literature shows that these adhesives chemically bond to tooth substrates and produce more stable and less hydrophilic dentin interfaces. However, some limitations exist when the use in selfetching mode is performed on enamel, and selective conditioning of this substrate is recommended. The use of these adhesives as a silane or primer in the cementation of glass-ceramics and metal alloys has also shown limitations. Nevertheless, in the cementation of zirconia-based ceramics and indirect composite resin-based restorations, the procedure can be simplified by the use of universal adhesives. Adhesive strength on dentin substrates under different conditioning modes varied between studies. As with any new material, long-term clinical evaluations are needed to demonstrate the efficacy of these universal adhesive agents, as reported in this literature review.

Os sistemas adesivos têm papel fundamental na adesão de materiais restauradores aos substratos dentários. Para que esta adesão seja cada vez mais eficaz e duradoura, estes materiais encontram-se em constante evolução buscando a simplificação de passos clínicos e diminuição da sensibilidade da técnica. A mais recente geração de adesivos desenvolvida é a dos adesivos universais, os quais prometem versatilidade e redução de passos clínicos. O objetivo deste trabalho foi realizar uma revisão de literatura sobre os adesivos universais e suas características. O levantamento bibliográfico foi realizado por meio de uma busca eletrônica na base de dados Pubmed. A literatura mostra que estes adesivos ligam-se quimicamente aos substratos dentários e produzem interfaces dentinárias mais estáveis e menos hidrofílicas. No entanto, algumas limitações existem quando o uso no modo autocondicionante é realizado em esmalte, sendo recomendado o condicionamento seletivo deste substrato. O uso destes adesivos como silano ou primer na cimentação de cerâmicas vítreas e ligas metálicas também demonstrou limitações. No entanto, na cimentação de cerâmicas a base de zircônia e nas restaurações indiretas a base de resina composta, o procedimento pode ser simplificado pelo uso dos adesivos universais. A resistência adesiva em susbstrato dentinário sob diferentes modos de condicionamento variou entre os estudos. Como qualquer novo material, avaliações clínicas de longo prazo são necessárias para demonstrar a eficácia destes agentes adesivos universais, conforme relatado nesta revisão de literatura.

Effect of alternative self-etch applications on dentin bond strength of "No Wait Concept" universal adhesives / Efecto de distintas alternativas de aplicación de los adhesivos universales con concepto de "no espera" en la resistencia adhesiva a la dentina

Abstract This study evaluated the effects of alternative self-etch application modes on resin-dentin microtensile bond strength (µTBS) of three commercially available "no wait" concept universal adhesives. In this study extracted impacted non-carious human third molars were used. The flat surfaces were prepared in mid-coronal dentin and prepared with a 600-grit SiC paper. The three universal adhesives that were used are as follows: Clearfil Universal Bond Quick (CUQ, Kuraray Noritake, Japan), G-Premio Bond (GPB, GC Corp, Japan), and a self-curing universal adhesive "Tokuyama Universal Bond" (TUB; Tokuyama Dental, Japan). The following three different application procedures were used for the dentin surfaces: the adhesives were applied and immediately subjected to air-dry; the adhesives were applied followed by a 10-second wait; or the adhesives were rubbed for 10 seconds. Then composite resin was applied to the dentin surface and light cured. After storage in 37°C distilled water for 24 h, all the bonded teeth were cut into 1mm² sections using a low-speed diamond saw (Micracut 125 Low Speed Precision Cutter, Metkon, Bursa, Turkey) under running water (n=15). The sections were subjected to a tensile force at a crosshead speed of 1mm/min in a testing apparatus (Microtensile Tester, Bisco, IL, USA) and µTBS values were measured. Data were analyzed using the Kruskal-Wallis test and Mann-Whitney U test. Failure modes were analyzed under a stereomicroscope. Prolonged application time significantly affected the µTBS (p<0.005). A significant increase of µTBS on active application was observed for CUQ and GPB. The TUB with an active application had a significantly lower µTBS value compared with the other adhesives. Prolonged application time caused significant improvement of bond strength in all adhesives. The active application is effective at increasing the dentin bond strength except for TUB.

Resumen Este estudio evaluó los efectos de los modos alternativos de aplicación de adhesivos de autograbado en la resistencia de la unión microtensil entre resina y dentina (µTBS) de tres adhesivos universales de concepto "no espera" disponibles en el mercado. En este estudio se utilizaron terceros molares humanos impactados que fueron extraídos. Las superficies planas se prepararon en la dentina coronal media y se prepararon con un papel SiC de 600 granos. Los tres adhesivos universales que se utilizaron son los siguientes: Clearfil Universal Quick Bond (CUQ, Kuraray Noritake, Japón), G-Premio Bond (GPB, GC Corp, Japón), y un adhesivo universal autopolimerizable "Tokuyama Universal Bond" (TUB; Tokuyama Dental, Japón). Se utilizaron los tres procedimientos de aplicación siguientes para las superficies dentinarias: se aplicaron los adhesivos y se sometieron inmediatamente a un secado al aire; se aplicaron los adhesivos y se esperó 10 segundos; o se frotaron los adhesivos durante 10 segundos. Luego se aplicó resina compuesta a la superficie dentinaria y se fotopolimerizó. Después de su almacenamiento en agua destilada a 37°C durante 24 h, todos los dientes unidos se cortaron en secciones de 1mm² utilizando una sierra de diamante de baja velocidad (Micracut 125 Low Speed Precision Cutter, Metkon, Bursa, Turquía) bajo agua corriente (n=15). Las secciones fueron sometidas a una fuerza de tracción a una velocidad de cruceta de 1mm/min en una máquina de prueba universal (Microtensile Tester, Bisco, IL, USA) y se midieron los valores de µTBS. Los datos fueron analizados utilizando la prueba de Kruskal-Wallis y la prueba U de Mann-Whitney. Los modos de falla fueron analizados bajo un estereomicroscopio. El prolongado tiempo de aplicación afectó significativamente a los µTBS (p<0,005). Se observó un aumento significativo de µTBS en la aplicación activa para el CUQ y el GPB. El TUB con una aplicación activa tuvo un valor de µTBS significativamente más bajo comparado con los otros adhesivos. El tiempo de aplicación prolongado causó una mejora significativa de la fuerza de adhesión en todos los adhesivos. La aplicación activa es efectiva para aumentar la fuerza de adhesión de la dentina, excepto para el TUB.

Ellagic acid on the quality of the adhesive interface of class I composite resin restorations after aging

To evaluate the effect of ellagic acid on the inhibition of matrix metalloproteinase by analyzing the quality of the adhesive interface with bond strength measures in periods of 24 hours and six months of storage. Method: 40 healthy human third molars were prepared with class I cavities (5x4x3mm). The teeth were divided into four experimental groups: Group 1- without application of ellagic acid and storage time of 24 hours; Group 2- with ellagic acid/24 hours; G3- without ellagic acid/six months; Group 4- with ellagic acid/six months. Then, the cavities were restored with Single Bond Universal adhesive and Z350 composite resin, with and without the previous application of ellagic acid. Subsequently, hourglass-shaped specimens were obtained and subjected to the bond strength (BS) test (n = 10) in a universal testing machine. The bond test was performed after 24 hours and six months of storage. For the standard evaluation (n = 3) the samples were infiltrated with silver nitrate and placed in a developing solution for analysis in a Scanning Electron Microscope (SEM). The data obtained were analyzed with the Kruskal-Wallis non-parametric test, showing a statistically significant difference. Results: The highest bond strength values were found for the 24-hour groups followed by the groups with six months of storage. For nano-infiltration, groups G1 and G2 showed lower infiltration than groups G3 and G4. Conclusion: The previous application of ellagic acid did not affect the BS of the adhesive interface of the adhesive system analyzed, regardless of storage time.

Endocrown as a restorative strategy in endodontically treated teeth: an integrative literature review / Endocrown como estratégia restauradora em dentes tratados endodonticamente: uma revisão integrativa da literatura

ABSTRACT With the consolidation of Adhesive Dentistry and the emergence of new aesthetic restorative materials, Endocrown has been studied as a rehabilitative option for endodontically treated teeth. This is an Integrative Literature Review, based on the PICO strategy, with articles selected from the databases of PubMed and BVS, with a period of time from 2011-2021. The database search strategy included the following keywords: ("Endocrown" OR "Endocrowns" OR "Endocrown Restoration" OR "no-post buildup" OR "adhesive endodontic crowns"). Inclusion criteria for this review were laboratory studies and observational clinical studies. Exclusion criteria were clinical case studies, literature review, systematic review and meta-analysis. Furthermore, articles that addressed only intraradicular retainers or other restorative strategies were also excluded. The selection of articles was based on abstracts. 5 articles were selected for analysis, obtaining data on the endocrown in relation to the stress on the tooth structure, aging, marginal adaptation, fracture resistance, endocrown versus conventional crown and integrity of the tooth structure. The findings in the literature are not yet established regarding the integrity of the dental structure, as the supporting evidence is limited. Only 1 in vitro article showed that dental failures in endocrowns are more favorable to repair and another 2 in silico studies show lower stress distribution on enamel, dentin and cement in the same restoration. Moreover, the restorative material seems to influence the possibility of fracture for both conventional crowns and endocrown restorations.

RESUMO Com a consolidação da Odontologia Adesiva e o surgimento de novos materiais restauradores estéticos, a Endocrown vem sendo estudada como uma opção reabilitadora para dentes tratados endodonticamente. Trata-se de uma Revisão Integrativa da Literatura, baseada na estratégia PICO, com artigos selecionados nas bases de dados da PubMed e BVS, com lapso temporal de 2011-2021. A estratégia de busca nas bases de dados foi utilizando as palavras chaves: ("Endocrown" OR "Endocrowns" OR "Endocrown Restoration" OR "no-post buildup" OR "adhesive endodontic crowns"). Os critérios de inclusão nesta revisão foram estudos laboratoriais e estudos clínicos observacionais. Os critérios de exclusão foram estudos de caso clínico, revisão de literatura, revisão sistemática e metanálise. Ademais, também foram excluídos artigos que abordavam apenas retentores intrarradiculares ou outras estratégias restauradoras. A seleção dos artigos foi realizada com base nos resumos. 5 artigos foram selecionados para análise, obtendo-se dados sobre a endocrown em relação à tensão sobre a estrutura dental, envelhecimento, adaptação marginal, resistência à fratura, endocrown versus coroa convencional, integridade da estrutura dental. Os achados da literatura ainda não estão estabelecidos em relação a integridade da estrutura dental, devido às evidências de apoio serem limitadas. Apenas 1 artigo in Vitro apresentou que as falhas dentais em endocrowns são mais favoráveis ao reparo e outros 2 estudos in Silico mostram menor distribuição de tensão sobre esmalte, dentina e cemento na mesma restauração. Além disso, o material restaurador parece influenciar a possibilidade de fratura tanto para as coroas convencionais quanto para as restaurações do tipo endocrowns.