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Aim: The aim of this study was to compare the microtensile bond strength (μTBS) and the characteristics of the adhesive interface of Scotchbond Universal - SU – etch-and-rise mode (3M ESPE) and Adper Scotchbond Multi-Purpose - MP (3M ESPE) to dentin over time. Methods: Class I cavity preparations were performed in 60 human molars that were randomly divided according to the dentin bonding system (DBS) used (n=30): (1) Acid conditioning + SU and (2) Acid conditioning + MP. For bonding strength (BS) analysis, 30 teeth (n = 15) were sectioned into sticks and submitted to the microtensile test in a universal testing machine after 24 hours and 12 months. The adhesive interface of the others 30 teeth was analyzed in a confocal microscope after 24 hours and 12 months. The data of μTBS were analyzed by two-way repeated measures ANOVA and Tukey’s HSD (α = 0.05). Results: SU presented the lowest DBS compared to MP (p=0.000). Time did not influenced DBS for both adhesive systems (p=0.177). Confocal microscopy analysis showed no cracks between both adhesive systems tested. Conclusion: The results indicate that MP - μTBS showed a better performance compared to SU in total-etch mode.

This in vitro study evaluated cell viability and metabolism, nitric oxide release and production of two chemokines and one cytokine by cultured human dental pulp fibroblasts (HDPF) in contact with two glass ionomer cements (Ketac Molar-KM and Vitrebond-VB), Single Bond (SB) and calcium hydroxide (Dycal-DY). Cultures of HDPF were established by means of an explant technique. The specimens were prepared under sterile conditions and in disks measuring 5 mm x 2 mm obtained from a prefabricated mold and placed on a permeable membrane to avoid direct contact with the cells. Cytotoxicity was assessed by Trypan Blue exclusion method and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Nitric oxide release in cell supernatant was detected by the Griess Method whereas stromal derived factor-1 alpha (SDF-1α or CXCL12), chemokine (C-X-C motif) ligand 8 [Interleukin 8 (IL-8 or CXCL8)] and interleukin-6 (IL-6) were detected by ELISA. RT-qPCR was employed for gene expression analysis. Statistical analyses were performed by One-way ANOVA followed by Tukey’s post hoc test for materials independent of the time, and Two-way ANOVA followed by Bonferroni correction test for the comparisons between materials and experimental time (p

This study evaluated in vitro cell viability and metabolism, nitric oxide release and production of chemokines by cultured human dental pulp fibroblasts (DPF) under contact with HEMA and Single Bond. Cultures of DPF were established by means of an explant technique. Once plated, cells were kept under contact with increasing concentrations of HEMA (10, 100 and 1000 nM) or Single Bond (SB) [10-fold serially diluted in culture medium (10-4, 10-3 and 10-2 v/v)] and also with polymerized SB components. Cytotoxicity was assessed by Trypan Blue exclusion method and MTT [3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. Nitric oxide release on cell supernatant was detected by Griess Method whereas chemokines (CXCL12 and CXCL8) were detected by ELISA. RT-qPCR was employed for chemokines gene expression analysis. Cytotoxic tests showed significant differences for SB 10-2. None of the tested materials significantly altered NO levels. Protein levels of CXCL12 were significantly decreased only by HEMA. On the other hand, while CXCL12 mRNA remained unaltered, gene expression of CXCL8 had significant decrease with all materials, except for polymerized SB. In conclusion, Single Bond and HEMA at various concentrations, decreased expression and production of molecules involved in inflammatory processes and, therefore, the use of adhesive systems such as pulp capping materials must be viewed with caution due to its large cytotoxic effect when in close contact with the pulp.

The purpose of this in vitro study was to evaluate the influence of depth (3.0 vs 5.0 mm) of mesio-occlusodistal (MOD) cavity preparation and mechanical cycling on fracture resistance of maxillary premolars restored with resin-based composite (RBC). Seventy premolars were randomly divided into 7 groups (n = 10): NP, no cavity preparation (control); MOD3, 3.0-mm-deep MOD preparation, not restored; MOD3R, 3.0-mm-deep MOD preparation restored with RBC; MOD5, 5.0-mm-deep MOD preparation, not restored; MOD5R, 5.0-mm-deep MOD preparation restored with RBC; MOD3RC, 3.0-mm-deep MOD preparation restored with RBC and subjected to mechanical cycling; and MOD5RC, 5.0-mm-deep MOD preparation restored with RBC and subjected to mechanical cycling under the same conditions as MOD3RC. All specimens were tested using a universal testing machine, resulting in the following mean (SD) values: NP, 224.65 (35.66) kgf; MOD3, 58.92 (15.48) kgf; MOD3R, 95.58 (13.88) kgf; MOD5, 68.06 (10.12) kgf; MOD5R, 98.49 (13.16) kgf; MOD3RC, 83.68 (14.39) kgf; and MOD5RC, 54.25 (11.56) kgf. Analysis of variance and Tukey test showed no statistically significant difference among MOD3, MOD5, and MOD5RC; between MOD5 and MOD3RC; or among MOD3R, MOD5R, and MOD3RC (P0.05). MOD3RC had significantly greater fracture resistance than MOD5RC (P0.05). NP had the highest fracture resistance of all groups (P0.05). The results showed that the depth of the cavity preparation only influenced fracture resistance after mechanical cycling of the specimens.

Interface integrity can be maintained by setting the composite in a layering technique and using liners. Objective The aim of this in vitro study was to verify the effect of resin-modified glass-ionomer cement (RMGIC) lining and composite layering technique on the bond strength of the dentin/resin adhesive interface of lateral walls of occlusal restorations. Material and Methods Occlusal cavities were prepared in 52 extracted sound human molars, randomly assigned into 4 groups: Group 2H (control) – no lining + two horizontal layers; Group 4O: no lining + four oblique layers; Group V-2H: RMGIC lining (Vitrebond) + two horizontal layers; and Group V-4O: RMGIC lining (Vitrebond) + four oblique layers. Resin composite (Filtek Z250, 3M ESPE) was placed after application of an adhesive system (Adper™ Single Bond 2, 3M ESPE) dyed with a fluorescent reagent (Rhodamine B) to allow confocal microscopy analysis. The teeth were stored in deionized water at 37oC for 24 hours before being sectioned into 0.8 mm slices. One slice of each tooth was randomly selected for Confocal Laser Scanning Microscopy (CLSM) analysis. The other slices were sectioned into 0.8 mm x 0.8 mm sticks to microtensile bond strength test (MPa). Data were analyzed by two-way ANOVA and Fisher’s test. Results There was no statistical difference on bond strength among groups (p>0.05). CLSM analysis showed no significant statistical difference regarding the presence of gap at the interface dentin/resin among groups. Conclusions RMGIC lining and composite layering techniques showed no effect on the microtensile bond strength and gap formation at the adhesive interface of lateral walls of high C-factor occlusal restorations.

Made available in DSpace on 2018-11-26T17:20:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-02-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Fluorescent dyes like Rhodamine B (RB) have been used to identify the spatial distribution of adhesive restorative materials in the tooth/restoration interface. Potential effects of the addition of RB to dental adhesives were addressed in the past, but no further information is available on how to determine suitable concentrations of RB in these bonding agents for imaging in the confocal laser scanning microscope. This study provides systematical strategies for adding RB to viscous dental adhesive resins, focusing on the determination of the lowest range of dye concentrations necessary to achieve an acceptable image of the dentin/adhesive interface. It was demonstrated that optimized images of the resin distribution in dentin can be produced with 0.1-0.02 mg/mL of RB in the (tested) adhesives. Our approaches took into account aspects related to the dye concentration, photophysical parameters in different host media, specimen composition and morphology to develop a rational use of the fluorescent agent with the resin-based materials. Information gained from this work can help optimize labeling methods using dispersions of low-molecular-weight dyes in different monomer blend systems. Univ Sao Paulo, Bauru Sch Dent, Dept Operat Dent Endodont & Dent Mat, BR-17012901 Bauru, SP, Brazil Univ Estadual Paulista, Inst Chem, Dept Inorgan Chem, BR-14800060 Araraquara, SP, Brazil Univ Sao Paulo, Bauru Sch Dent, Dept Prosthodont, BR-17012901 Bauru, SP, Brazil Univ Sao Paulo, Sch Dent, Dept Operat Dent, BR-05508000 Sao Paulo, SP, Brazil Univ Estadual Paulista, Inst Chem, Dept Inorgan Chem, BR-14800060 Araraquara, SP, Brazil FAPESP: 2011/14971-2 FAPESP: 2012/13160-3 FAPESP: 2013/13161-2

Aim Adhesion can be influenced by adhesives spreading. Both slow and fast spreading can be deleterious as they can respectively lead adhesive to partially cover the demineralized substrate or to accumulate on line angles of cavity preparations. Since brands of dentin bonding systems present distinct compositions and thus different behaviors its important to know how fast they spread over dental substrates. The purpose is to determine the influence of surface inclinations on the spreading velocity of simplified adhesive systems. Materials and methods Spreading velocities of adhesive systems (Adper Single Bond, Adper Single Bond Plus, Adper Prompt, Prime and Bond 2.1, Prime and Bond NT, One-Up Bond F) were measured on glass slide surfaces inclined at 45° and 90°. The spreading of each drop was observed at a 30 seconds interval. Data was recorded and the values obtained at 30 seconds were analyzed by two-way ANOVA and Student-Newman-Keuls (SNK) tests (α = 0.05). Results The type of adhesive system and the angle of inclination influenced spreading velocity (p < 0.05). Adper Single Bond Plus and One-Up Bond F exhibited the lowest spreading velocities of all materials tested (p < 0.01). Adhesives spreading were similar on surfaces inclined 45° and 90°, except for Adper Single Bond Plus which spread faster and Prime and Bond NT that spread slower on 90° angled surfaces (p < 0.01). Conclusion The materials tested showed complex spreading patterns since the spreading velocities changed only when some specific material/inclination combinations where tested. How to cite this article Pazinatto FB, de Castro FLA, Saini R, Atta MT. Influence of Surface Inclination on the Spreading Velocity of Simplified Adhesive Systems. Int J Experiment Dent Sci 2013;2(2):92-97.

This study evaluated the impact of orange juice on the bond strength (BS) of dentin bonding systems (DBSs) to enamel surface after simulation with an in situ/ ex vivo erosive cycling. One hundred and ninety two bovine enamel fragments (4x4x2mm) were obtained and randomized regarding superficial microhardness and distributed to palatal devices for 8 volunteers, in three phases (one for each DBS), containing 8 blocks, which were, allocated in 4 pairs. Daily, these pairs were subjected extraorally to the following conditions: CONT- neither erosive nor abrasive challenge; ERO- erosive challenge only; ABR- abrasive challenge only and ERO + ABR- with erosive and abrasive challenges. Erosive cycles (immersion in orange juice, 3 times/day/5 min/5 days) or/and abrasive challenges (electric toothbrush, 3 times/day/1 min/5 days) were performed. After these cycles, all specimens were restored with the adhesive systems Adper Scotchbond Multi Purpose (MP), Adper Single Bond 2 (SB) or Clearfil SE Bond (SE), and the composite resin Filtek Z250. After 7 days, sticks (area ≅1 mm2) were obtained and subjected to the microtensile bond strength test (μTBS) at 0.5 mm/min. Data was statistically analyzed by ANOVA and Tukey tests (a=0.05). Failure modes were determined using a digital microscope (40´). DBS was the only statistical significant factor. SE was the unique DBS not affected in any challenge, whereas MP and SB performed according to the scenario. The adhesive and mixed failures were predominant in all groups. Overall performance suggested that BS to enamel after erosive /abrasive challenged by orange juice was not affected and it was material-dependent. Resumo Este estudo avaliou o impacto de suco de laranja na resistência de união (RU) de sistemas adesivos dentinários (SAD) à superfície do esmalte após a simulação com uma ciclagem erosiva in situ/ex vivo. Cento e noventa e dois fragmentos de esmalte bovino (4x4x2mm) foram obtidos e randomizados considerando a microdureza superficial, e distribuídos em dispositivos palatinos para 8 voluntários, em três fases (uma para cada SAD), contendo 8 blocos, os quais foram alocados em 4 pares. Diariamente, esses pares eram submetidos às seguintes condições extraoralmente: CONT- sem desafio erosivo ou abrasivo; ERO- desafio erosivo somente; ABR- desafio abrasivo somente; e ERO+ABR- com desafio erosivo e abrasivo. A ciclagem erosiva (imersão em suco de laranja, 3 vezes/dia/5 min/5 dias) e/ou ciclagem abrasiva (escova dentária elétrica, 3 vezes/dia/1 min/5 dias) foram feitas. Após estas ciclagens, todos os espécimes foram restaurados com os sistemas adesivos Adper Scotchbond Multi Purpose (MP), Adper Single Bond 2 (SB) ou Clearfil SE Bond (SE), e com a resina composta Filtek Z250. Após 7 dias, palitos (área ≈1 mm) eram obtidos e submetidos ao teste de resistência de união por microtração (μTBS) a 0,5 mm/min. Os dados foram estatisticamente analisados por ANOVA e teste de Tukey (a=0,05). Os modos de fratura foram determinados utilizando um microscópio digital (40×). SAD foi o único fator estatisticamente significante. SE foi o único SAD não afetado por qualquer desafio, enquanto o MP e o SB apresentaram um desempenho de acordo com o cenário. As fraturas do tipo mista e adesiva foram predominantes em todos os grupos. O desempenho geral sugeriu que RU ao esmalte após desafio erosivo/abrasivo por suco de laranja não foi afetada e foi material-dependente.

Objective This study investigated the effect of the fluorescent dye rhodamine B (RB) for interfacial micromorphology analysis of dental composite restorations on water sorption/solubility (WS/WSL) and microtensile bond strength to dentin (µTBS) of a 3-step total etch and a 2-step self-etch adhesive system. Material and Methods The adhesives Adper Scotchbond Multi-Purpose (MP) and Clearfil SE Bond (SE) were mixed with 0.1 mg/mL of RB. For the WS/WSL tests, cured resin disks (5.0 mm in diameter x 0.8 mm thick) were prepared and assigned into four groups (n=10): MP, MP-RB, SE, and SE-RB. For µTBS assessment, extracted human third molars (n=40) had the flat occlusal dentin prepared and assigned into the same experimental groups (n=10). After the bonding and restoration procedures, specimens were sectioned in rectangular beams, stored in water and tested after seven days or after 12 months. The failure mode of fractured specimens was qualitatively evaluated under optical microscope (x40). Data from WS/WSL and µTBS were assessed by one-way and three-way ANOVA, respectively, and Tukey’s test (α=5%). Results RB increased the WSL of MP and SE. On the other hand, WS of both MP and SE was not affected by the addition of RB. No significance in µTBS between MP and MP-RB for seven days or one year was observed, whereas for SE a decrease in the µTBS means occurred in both storage times. Conclusions RB should be incorporated into non-simplified DBSs with caution, as it can interfere with their physical-mechanical properties, leading to a possible misinterpretation of bonded interface.

Objectives: The aim of this study was to investigate the superficial texture of composite restorations after different bleaching protocols. Methods: Filtek Supreme (S), Filtek Z350 (F), and Grandio (G) were compared to Opallis (O) and Filtek Z250 (Z) (control microhybrid composites) and to bovine enamel using three different bleaching agents: 35% hydrogen peroxide Whiteness HP (WHP), 35% Whiteness HP MAXX (WMAXX) and 16% carbamide peroxide Whiteness Standard (WS). Six specimens from each composite were treated using each bleaching agent, according to the manufacturers’ instructions. Three random sites were measured for superficial roughness (Hommel Tester T 1000) weekly for each sample. Data were analyzed for each bleaching system using two-way ANOVA and Bonferroni tests at 5% significance level. Results: WHP treatment significantly altered the Filtek Supreme composite over time. When WMAXX was used, Grandio displayed the most significant alterations in surface roughness throughout the evaluation period, which was not observed for the other nanocomposites. Using WS, Filtek Z250 presented significant surface alterations over time, which was not seen in the nanofilled materials. Conclusions: Surface roughness alteration was material and time-dependent. The bleaching gels affected nanofilled and microhybrid composite resins. Enamel was the surface less affected by bleaching. (Eur J Dent 2011;5:173-179)

Statement of the Problem: Adhesive systems can spread differently onto a substrate and, consequently, influence bonding. Purpose: The purpose of this study was to evaluate the effect of differently oriented dentin surfaces and the regional variation of specimens on adhesive layer thickness and microtensile bond strength (MTBS). Materials and Methods: Twenty-four molars were sectioned mesiodistally to expose flat buccal and lingual halves. Standardized drop volumes of adhesive systems (Single Bond [SB] and Prime & Bond 2.1 [PB2.1]) were applied to dentin according to the manufacturer's instructions. Teeth halves were randomly divided into groups: 1A-SB/parallel to gravity; 1B-SB/perpendicular to gravity; 2A-PB2.1/parallel to gravity; and 2B-PB2.1/perpendicular to gravity. The bonded assemblies were stored in 37°C distilled water for 24 hours and then sectioned to obtain dentin sticks (0.8 mm2). The adhesive layer thickness was determined in a light microscope (×200), and after 48 hours the specimens were subjected to MTBS test. Data were analyzed by one-way and two-way analysis of variance and Student–Newman–Keuls tests. Results: Mean values (MPa ± SD) of MTBS were: 39.1 ± 12.9 (1A); 32.9 ± 12.4 (1B); 52.9 ± 15.2 (2A); and 52.3 ± 16.5 (2B). The adhesive systems' thicknesses (µm ± SD) were: 11.2 ± 2.9 (1A); 18.1 ± 7.3 (1B); 4.2 ± 1.8 (2A); and 3.9 ± 1.3 (2B). No correlation between bond strength and adhesive layer thickness for both SB and PB2.1 (r = –0.224, p = 0.112 and r = 0.099, p = 0.491, respectively) was observed. Conclusions: The differently oriented dentin surfaces and the regional variation of specimens on the adhesive layer thickness are material-dependent. These variables do not influence the adhesive systems' bond strength to dentin. CLINICAL SIGNIFICANCE Adhesive systems have different viscosities and spread differently onto a substrate, influencing the bond strength and also the adhesive layer thickness. Adhesive thickness does not influence dentin bond strength, but it may impair adequate solvent evaporation, polymer conversion, and may also determine water sorption and adhesive degradation over time. In the literature, many studies have shown that the adhesive layer is a permeable membrane and can fail over timebecause ofits continuous plasticizing and degradation when in contact with water. Therefore, avoiding thick adhesive layers may minimize these problems and provide long-term success for adhesive restorations.

O Cimento de ionômero de vidro foi inventado no início da década de 70 do século passado, a partir do desenvolvimento do cimento de silicato. Desde então, passou a exercer um papel significante na odontologia restauradora. Primeiramente, era utilizado apenas como material restaurador em cavidades pequenas, posteriormente, passou a ser utilizado como material de cimentação de peças protéticas, como núcleo de preenchimento, material para base e forramento de cavidades dentárias e selamentos de fóssulas e fissuras. Mais recentemente passou a ser o material de escolha na técnica restauradora atraumática (ART), e também tem sido utilizado na medicina e fonoaudiologia em tratamentos em regiões ósseas. Sua popularidade evidenciou-se devido as suas propriedades biologicamente favoráveis, pois apesar de ainda possuir uma solubilidade inicial crítica e um comportamento estético insatisfatório, o cimento ionomérico libera flúor para o meio bucal, possui uma adesão química à estrutura dental e demonstra ser biocompatível. Com isso, ele evidencia propriedades anticariogênicas importantes, podendo assim ser utilizado em diversas situações na odontologia.

The glass ionomer cement was developed in the past century 70s, after continuous researches about silicate cement. Over the years, glass ionomers have been playing an important role on restorative dentistry. Initially, the material was used for restoration of small cavities, however, its usage has been increased. The main indications at present are: as core buildup restorative, luting cement, liner and base and as a sealant. Recently, glass ionomer cement has been used for ART restorations and in some medicine fields because of the positive biointeraction with bone cells. Although glass ionomer cements exhibit an initial critical solubility and poor aesthetics, great biological properties like fluoride release to oral environment, chemical bonding to tooth tissues and biocompatibility leads this material elective for many purposes. Finally, their inherent antimicrobial properties contributes to the treatment of many situations in dentistry.

Aim This study tested the null hypothesis that there is no difference on microleakage of dentin-bordered composite restorations using single or double coats of adhesive from one-bottle adhesive systems. Methods and Materials The enamel surface was removed from freshly extracted bovine teeth, and standardized Class V cavities (3 x 3 x 1.5 mm) were made at the cervical areas of buccal surfaces. Teeth were restored and grouped according to type of adhesive systems [Prime Bond 2.1 (PB2.1), Prime & Bond NT (PBNT), and Single Bond (SB)] and to the number of coats (one or two) to be used. The restorations were polished and immersed in a 0.5% aqueous solution of basic fuchsin for four hours. Teeth were then sectioned and the most infiltrated section of each tooth was selected under magnification, scanned, and quantitatively analyzed using a computer program. Data were analyzed using two-way analysis of variance (ANOVA) and Student-Newman-Keuls (α=0.05). Results Groups without filler content (PB2.1 and SB) showed no difference in microleakage using single or double coats. However, PBNT (with nanofiller) showed statistically less microleakage when only one coat was applied. The influence of the number of coats of the adhesive systems on dentin margin microleakage was material dependent. Conclusion All adhesive systems demonstrated microleakage, however, it could be minimized using two coats of non-filled or one coat of a filled adhesive system. Citation Harada TS, Pazinatto FB, Wang L, Atta MT. Effect of the Number of Coats of Simplified Adhesive Systems on Microleakage of Dentin-Bordered Composite Restorations. J Contemp Dent Pract 2006 November;(7)5:034-041.

www.scielo.br/jaos bjective: This study evaluated the performance of different adhesive systems in fiber post placement aiming to clarify the influence of different hydrophobic experimental blend adhesives, and of one commercially available adhesive on the frictional retention during a luting procedure. Material and Methods: One luting agent (70 Wt% BisGMA, 28.5% TEGDMA; 1.5% p-tolyldiethanolamine) to cement fiber posts into root canals was applied with 4 different adhesive combinations: Group 1: The etched roots were rinsed with water for 30 s to remove the phosphoric acid, then rinsed with 99.6% ethanol for 30 s, and blot- dried. A trial adhesive (base to catalyst on a 1:1 ratio) was used with an experimental luting agent (35% Bis-GMA, 14.37% TeGDMA, 0.5% eDMAB, 0.13% CQ); Group 2: A trial adhesive (base to catalyst on a 1:2 ratio ) was luted as in Group 1; Group 3: One-Step Plus (OSP, Bisco Inc.) following the ethanol bonding technique in combination with the luting agent as in Group 1; Group 4: OSP strictly following the manufacturer's instructions using the luting agent as in Group 1. The groups were challenged with push-out tests. Posted root slices were loaded until post segment extrusion in the apical-coronal direction. Failure modes were analyzed under scanning electron microscopy. Results: Push-out strength was not significantly influenced by the luting agent (p>0.05). No statistically significant differences among the tested groups were found as Group 1 (exp 1 - ethanol-wet bonding technique)=Group 2 (exp 2 - ethanol-wet bonding technique)=Group 3 (OSP - ethanol-wet bonding technique)=Group 4 (control, OSP - water-wet bonding technique) (p>0.05). The dominating failure modes in all the groups were cohesive/adhesive failures, which were predominantly observed on the post/luting agent interface. Conclusions: The results of this study support the hypothesis that the proposal to replace water with ethanol to bond fiber posts to the root canal using highly hydrophobic resin is plausible, but this seems to be more the proof of a concept than a clinically applicable procedure.

To evaluate the effect of bleaching techniques on dentin permeability. The hypothesis was that the bleaching agent associated or not to etching and/or energy source would be able to increase dentin permeability (conductance).Fifty 1 mm-thick disks of mid-coronal dentin were obtained from human third molars, which were mounted in a filtration chamber, allowing exposure of a standardized area of 0.282 mm2. All specimens were treated with 35% liquid phosphoric acid for 15 seconds to maximize dentin permeability. Then they were randomly allocated to five different conditions: C: placebo gel (negative control); HP: Whiteness HP Maxx (WM)-35% hydrogen peroxide; PA-HP: WM preceded by phosphoric acid etching for 15 seconds. HP-E: WM associated to a light source and PA-HP-E: WM preceded by phosphoric acid etching for 15 seconds and associated to a light source. The bleaching agent was applied for 10 minutes with intermediate agitation at 5 minutes. In the groups associated with a light source, it was activated for 30 seconds every 5 minutes. Afterwards, the permeability (Lp) was measured using the Flodec device. The data were collected and analyzed with one-way ANOVA and Tukey's test (P0.05).Mean and standard deviation of Lp were: C = 1.92 (1.04); HP = 1.14 (0.29); PA-HP = 14.40 (8.62); HP-E = 4.18 (5.14); PA-HP-E = 27.32 (13.24). Data revealed that phosphoric acid etching could increase the dentin permeability, while the bleaching agent or light curing alone did not.

Objective To evaluate the prevalence, types, location, and characteristics of enamel defects in anterior permanent teeth of patients with complete unilateral and bilateral cleft lip and palate, as well as the relation with the cleft. Setting Hospital for Rehabilitation of Craniofacial Anomalies, Bauru, São Paulo, Brazil. Participants Eighty patients of both genders, 12 years and older, with unilateral or bilateral cleft lip and palate. Methods A single examiner carried out clinical examination under artificial light with a dental probe and mirror after drying teeth according to the modified DDE index. Results Seventy-four of 80 patients presented with at least one tooth affected by enamel defects: 165 of 325 evaluated teeth (50.8%) presented enamel defects, with hypoplasia being the most prevalent (50.7%), followed by diffuse opacity (23.1%) and demarcated opacity (18.4%). The most affected tooth was 21 (36.5%), followed by 11 (34%), located at the middle (40%) and incisal (33%) thirds. Most defects occur at the buccal surface (47.7%), followed by the distal (22.7%), the mesial (19%), and the palatal (10.6%) surfaces. A significant relationship was found between the cleft side and enamel defects. Conclusion Upper anterior teeth of patients with complete cleft lip and palate present a high prevalence of enamel defects; the highest percentage on the cleft side suggests that the cleft does influence the occurrence of enamel defects in permanent teeth.

The influence of curing tip distance and storage time in the kinetics of water diffusion (water sorption-W SP, solubility-W SB, and net water uptake) and color stability of a composite were evaluated. Composite samples were polymerized at different distances (5, 10, and 15 mm) and compared to a control group (0 mm). After desiccation, the specimens were stored in distilled water to evaluate the water diffusion over a 120-day period. Net water uptake was calculated (sum of WSP and WSB). The color stability after immersion in a grape juice was compared to distilled water. Data were submitted to three-way ANOVA/Tukey's test (α = 5%). The higher distances caused higher net water uptake (p < 0.05). The immersion in the juice caused significantly higher color change as a function of curing tip distance and the time (p < 0.05). The distance of photoactivation and storage time provide the color alteration and increased net water uptake of the resin composite tested.

The influence of curing tip distance and storage time on the hardness of a composite was evaluated. Composite samples (Filtek Z250) were polymerized at different distances (5, 10, and 15 mm), compared with a control group (0 mm), and stored in distilled water at 37 ° C for 24 hours. The Knoop-hardness of top and bottom surfaces was assessed (25 g/30 s). Specimens were stored in distilled water for 6 and 12 months and were retested. Hardness was found to be negatively influenced by both curing tip distance and storage time. Despite similar values at 24 hours, differences in hardness values compared with the control group appeared over time. In comparing both surfaces, hardness proved to be greater at the top surface for all groups. Composites with similar initial hardness values can degrade very differently after water storage. The higher the photoactivation distance and storage time, the worse the mechanical property.

The aim of this in vitro study was to analyze the effect of glass-ionomer cement as a liner on the dentin/resin adhesive interface of lateral walls of occlusal restorations after thermocycling.Occlusal cavities were prepared in 60 human molars, divided into six groups: no liner (1 and 4); glass-ionomer cement (GIC, Ketac Molar Easymix, 3M ESPE) (2 and 5); and resin-modified glass-ionomer cement (RMGIC, Vitrebond, 3M ESPE) (3 and 6). Resin composite (Filtek Z250, 3M ESPE) was placed after application of an adhesive system (Adper Single Bond 2, 3M ESPE) that was mixed with a fluorescent reagent (Rhodamine B) to allow confocal microscopy analysis. Specimens of groups 4, 5 and 6 were thermocycled (5°C-55°C) with a dwell time of 30 seconds for 5000 cycles. After this period, teeth were sectioned in approximately 0.8-mm slices. One slice of each tooth was randomly selected for confocal microscopy analysis. The other slices were sectioned into 0.8 mm × 0.8 mm beams, which were submitted to microtensile testing (MPa). Data were analyzed using two-way ANOVA and Tukey test (p0.05).There was no detectedstatistical difference on bond strength among groups (α0.05). Confocal microscopy analysis showed a higher mean gap size in group 4 (12.5 μm) and a higher percentage of marginal gaps in the thermocycled groups. The RMGIC liner groups showed the lowest percentage of marginal gaps.Lining with RMGIC resulted in less gap formation at the dentin/resin adhesive interface after artificial aging. RMGIC or GIC liners did not alter the microtensile bond strength of adhesive system/resin composite to dentin on the lateral walls of Class I restorations.

Objectives The aim of this study was to evaluate the Knoop microhardness (KHN) and chemical composition of high-viscous glass-ionomer cement (HVGIC) after 10 years of clinical service. Methods Six HVGIC samples were cut from 10-year ART restorations. The sections were embedded in acrylic moulds with their longitudinal profile exposed. KHN was determined by performing three sequences of five indentations at 10, 30, 50, 70 and 90 μm of HVGIC outer surface. For the control group ( n = 6), HVGIC specimens were stored in distilled water for 24 months. Hardness measurements were taken at days 7, 30, 60, 120, 180, 360, and 720. For chemical analysis using SEM-EDX, 10-year and control specimens were dehydrated and coated with carbon. Data were analysed using T -test and ANOVA/Tukey's test ( p Results A significant KHN increase was observed in the control group up to the 180-day period. From this point the values stabilized and no more significant differences were found between the 10-year and the control KHN values. No statistical differences were observed amongst the KHN from inner distances compared to the outer surface of the 10-year HVGIC specimens. In one 10-year specimen, SEM-images identified the transformation of HVGIC in an altered layer with no glass filler particles detectable, and raised Ca, K and P contents. Conclusions KHN values of ten-year HVGIC specimens were similar to the control group values at 180-day storage period. Except for one 10-year specimen in that an altered layer could be seen, chemical composition was similar amongst the depths evaluated.

As resin-modified glass-ionomer cement (RMGIC) is an adhesive material, its association to dentin bonding agents (DBAs) was previously proposed. This study investigated the adjunctive behavior of an RMGIC with etch-and-rinse bonding systems under in situ/ex vivo cariogenic challenge.Bovine enamel blocks (3 3 3 3 2 mm) were randomly assigned to group VP, Vitremer + its own primer (3M ESPE); group VSB, Vitremer + Single Bond (3M ESPE); and group VPB, Vitremer + Prime and Bond 2.1 (Dentsply). Two blocks of each group were randomly placed in an acrylic palatal appliance, so each appliance included six blocks. Volunteers (n = 10) wore these appliances according to given instructions to promote a sucrose challenge eight times/day for 15 days. After this period, the blocks were removed from the devices and cleaned, and demineralization was assessed through longitudinal microhardness analysis (Knoop indenter, 25 g/5 s). Data were submitted to three-way ANOVA and Tukey test (P.05).No treatment was able to completely avoid demineralization. All materials showed a statistically significant difference in mineral loss when the microhardness on the outer enamel was compared with deeper regions (P.05).Association of the tested RMGICs with etch-and-rinse DBAs did not seem to be more beneficial against caries than the conventional treatment with RMGIC.

OBJECTIVES: Production of acids such as lactic acid contributes to establish a cariogenic environment that leads to dental substrate demineralization. Fluoride plays an important role in this case and, as fluoride-releasing materials, glass-ionomer cements are expected to contribute to minimize deleterious reactions. This study evaluated interactions of glass-ionomer cements used in atraumatic restorative treatment (ART-GICs) with an aqueous lactic acid solution, testing the null hypotheses that no changes occur in the pH of the solution or on the surface roughness and mass of the ART-GICs when exposed to lactic acid solution over a 6-week period. MATERIAL AND METHODS: Ketac Molar, Fuji IX, Vitro Molar and Magic Glass were tested, and compared to Filtek Z250 and Ketac Fil Plus as control groups. Six specimens of each material were made according to manufacturers' instructions. The pH of the solution and roughness and mass changes of each specimen were determined over 6 weeks. Each specimen was individually stored in 2 mL of 0.02 M lactic acid solution for 1 week, renewing the solution every week. pH of solution and mass of the specimens were monitored weekly, and surface roughness of the specimens was assessed before and at the end of the 6-week acid challenge. pH and mass data were analyzed statistically by repeated measures using one-way ANOVA and Tukey's post-hoc tests for each material. Paired t-tests were used for roughness analysis. Tukey's post-hoc tests were applied to verify differences of final roughness among the materials. Significance level was set at 5%. RESULTS: The null hypotheses were partially rejected. All materials were able to increase the pH of the lactic acid solution and presented rougher surfaces after immersion, while mass change was minimal and generally not statistically significant. CONCLUSIONS: These findings can be helpful to predict the performance of these materials under clinical conditions. A protective action against the carious process with significant surface damage due to erosion may be expected.

The tensile bond strengths of five retention techniques for bonded cast restorations were tested. The retentive methods were the electrolytic etch, Rochette's perforations, retention beads, the recessed surface, and soldered orthodontic mesh. The electrolytic etch and recessed surface methods gave the highest values of bond strength, followed by retention beads. Rochette's perforations and the soldered orthodontic mesh failed to surpass the bond strength of the control group (no additional retention) after 1 hour and provided the lowest bond strength after 24 hours.

Background: Flowability and viscosity vary for different adhesive systems owing to differences in their composition. These characteristics can be modified by environmental temperature. Purpose: The purpose of this study was to determine the influence of temperature on the spreading (flow capacity) of simplified-step adhesive systems. Materials and Methods: Spreading velocities of adhesive systems (Adper Single Bond and Single Bond Plus [3M ESPE, St. Paul, MN, USA]; Prime & Bond 2.1 and Prime & Bond NT [Dentsply Industria e Comercio Ltda, Petropolis, RJ, Brazil]; Adper Prompt [3M ESPE]; and One Up Bond F [Tokuyama Corp, Tokyo, Japan]) were analyzed at intervals of 10, 15, 20, and 30 seconds at both 25°C and 37°C by placing 10 μL drops on a glass slide surface with an inclination of 45°. The spreading of each adhesive system was measured in millimeters per second. Results: Data were analyzed by two-way analysis of variance and Student-Newman-Keuls tests. Regression analysis was used to determine a correlation between spreading velocity and time. Statistical significance was considered at a confidence level of 95%. Temperature influenced the spreading velocity, increasing it for Single Bond and Prime & Bond 2.1 and decreasing it for Adper Prompt (p .05). Regression analysis of each adhesive system demonstrated an inverse correlation between mean spreading velocity and time (R2 = .999) on both temperatures. Conclusions: Temperature increases yielded an increase of spreading for Single Bond and Prime & Bond 2.1. The influence of temperature on the spreading velocity was material dependent. CLINICAL SIGNIFICANCE Environmental temperature can influence the rate of spreading of the adhesive system in clinically relevant times and may influence adhesive thickness on cavity walls.

A dhesive systems associated to resin-modified glass ionomer cements are employed for the achievement of a higher bond strength to dentin. Despite this benefit, other properties should not be damaged. This study aimed at evaluating the short-time fluoride release of a resin-modified glass ionomer cement coated with two one-bottle adhesive systems in a pH cycling system. Four combinations were investigated: G1: Vitremer (V); G2: Vitremer + Primer (VP); G3: Vitremer + Single Bond (VSB) and G4: Vitremer + Prime & Bond 2.1 (VPB). SB is a fluoride-free and PB is a fluoride-containing system. After preparation of the Vitremer specimens, two coats of the selected adhesive system were carefully applied and light-cured. Specimens were immersed in demineralizing solution for 6 hours followed by immersion in remineralizing solution for 18 hours, totalizing the 15-day cycle. All groups released fluoride in a similar pattern, with a greater release in the beginning and decreasing with time. VP showed the greatest fluoride release, followed by V, with no statistical difference. VSB and VPB released less fluoride compared to V and VP, with statistical difference. Regardless the one-bottle adhesive system, application of coating decreased the fluoride release from the resin-modified glass ionomer cements. This suggests that this combination would reduce the beneficial effect of the restorative material to the walls around the restoration. Sistemas adesivos são associados aos cimentos de ionômero de vidro modificados por resina para a obtenção de maior resistência adesiva à dentina. Apesar deste benefício, outras propriedades não devem ser prejudicadas. Este estudo se propôs a avaliar a liberação de flúor a curto prazo de um cimento de ionômero de vidro modificado por resina coberto com dois diferentes sistemas adesivos em um modelo de ciclagem de pH. Quatro associações foram testadas: G1: Vitremer (V); G2: Vitremer + Primer (VP); G3: Vitremer + Single Bond (VSB) and G4: Vitremer + Prime & Bond 2.1 (VPB). SB é um sistema sem flúor e PB contém flúor. Após a confecção das amostras de Vitremer, duas camadas de cada sistema selecionado foram aplicadas e fotopolimerizadas. Em seguida, as amostras foram imersas em solução desmineralizante por 6 horas, seguida da imersão em solução remineralizante por 18 horas, totalizando 15 dias de ciclagem. Todos os grupos liberaram flúor sob o mesmo padrão, apresentando maior liberação inicial e decrescendo ao longo do tempo. VP apresentou a maior liberação de flúor, seguida de V, sem diferença estatística. VSB and VPB liberaram menor quantidade de flúor em relação a V e VP, com diferenças estatisticamente significantes. Independentemente do sistema adesivo de frasco único, houve redução da liberação de flúor pelo cimento de ionômero de vidro modificado por resina. Isto sugere que esta associação poderia reduzir o efeito benéfico do material restaurador em torno da restauração.

Thermocycling simulates, in vitro, thermal changes that occur in the oral cavity. The aim of this study was to evaluate the influence of the number of cycles on microleakage. Class V cavities (1.5 mm deep, 3 mm in height and 3 mm in width) were prepared in bovine teeth, restored with a Single Bond/Z250 restorative system (3M/ESPE) and then divided into five groups of ten teeth each: group 1 was not thermocycled (control group), and groups 2, 3, 4 and 5 were thermocycled 500, 1,000, 2,500 and 5,000 times, respectively (5º-55º ± 2ºC, 15 s dwell time). The teeth were immersed in 0.5% basic fuchsin aqueous solution for 24 h, sectioned and the sections with the highest degree of microleakage were selected, scanned and the extent of dye penetration was measured by the ImageTool program. The results submitted to one-way ANOVA showed no significant differences between the groups (p >; 0.05). The averages of microleakage values in millimeters were: group 1 (3.92); group 2 (3.13); group 3 (4.48); group 4 (4.33) and group 5 (3.42). Thus, it was concluded that there is no relation between the increase of the number of cycles and the increase in microleakage. A ciclagem térmica tem por objetivo simular, in vitro, as mudanças térmicas intra-orais que ocorrem clinicamente. Sendo o seu efeito bastante discutido, o presente trabalho tem como objetivo avaliar a relação da ciclagem térmica e o número de ciclos na infiltração marginal. Foram confeccionadas cavidades classe V com dimensões de 3 mm de altura, 3 mm de largura e 1,5 mm de profundidade, em dentes bovinos. Os dentes foram restaurados com o sistema Single Bond/Z250 (3M/ESPE) e, então, divididos em 5 grupos de 10 dentes cada: grupo 1 (controle) sem ciclagem; grupos 2, 3, 4 e 5 com 500, 1.000, 2.500 e 5.000 ciclos, respectivamente (5º-55º ± 2ºC, 15 segundos por banho). A seguir, os dentes foram seccionados e analisados em microscópio com 100 X de aumento para a escolha da fatia mais infiltrada, que foi escaneada e quantificada pelo programa ImageTool. Os dados submetidos ao teste ANOVA a um critério não apresentaram diferença significante (p >; 0,05), resultando em valores médios de infiltração em milímetros: grupo 1 (3,92), grupo 2 (3,13), grupo 3 (4,48), grupo 4 (4,33) e grupo 5 (3,42). A análise dos dados permitiu concluir que não há relação entre o aumento do número de ciclos e o aumento da infiltração marginal.

Six patients enrolled at the Hospital of Rehabilitation of Craniofacial Anomalies, University of São Paulo, aging 16 to 20 years, were selected. All patients presented with white spots in both sides of the superior arch, which totalized 41 spots. The left side of the arch was submitted to remineralization by means of the conventional technique with Reminer, a commercially available product. In the right side, a modified technique was employed, with the utilization of fluoridated dentifrices every night, during 8 weeks. It was observed that successful remineralization occurred in 62% of the spots when the conventional technique was employed, whereas, when fluoridated dentifrices were utilized, there was partial remineralization in 10% of the spots. The utilization of Reminer was more effective than the utilization of fluoridated dentifrices.

Foram selecionados seis pacientes do Hospital de Reabilitação de Anomalias Craniofaciais da Universidade de São Paulo, com idade entre 16 e 20 anos, apresentando um total de 41 manchas brancas nos dois lados da arcada superior. No lado esquerdo da arcada, foi feita remineralização utilizando-se a técnica com o produto comercial Reminer. No lado direito, foi utilizada uma técnica modificada, com o uso de dentifrícios fluoretados pelo paciente durante a noite, diariamente, em um período de oito semanas. Observou-se remineralização em 62% das manchas com o uso da técnica com Reminer e remineralização parcial em 10% das lesões com a utilização de dentifrícios fluoretados. A utilização do produto comercial Reminer apresentou-se mais eficaz que o uso de dentifrícios fluoretados. Six patients enrolled at the Hospital of Rehabilitation of Craniofacial Anomalies, University of São Paulo, aging 16 to 20 years, were selected. All patients presented with white spots in both sides of the superior arch, which totalized 41 spots. The left side of the arch was submitted to remineralization by means of the conventional technique with Reminer, a commercially available product. In the right side, a modified technique was employed, with the utilization of fluoridated dentifrices every night, during 8 weeks. It was observed that successful remineralization occurred in 62% of the spots when the conventional technique was employed, whereas, when fluoridated dentifrices were utilized, there was partial remineralization in 10% of the spots. The utilization of Reminer was more effective than the utilization of fluoridated dentifrices.

The concepts introduced by the Minimally Invasive Dentistry (MID) allowed the rising of new conservative treatment and assessment system for caries lesions’ classification. In this context, the approaches of the incipient caries lesions surpass the use of only traditional restorative techniques. The aim of this study was to review the new caries classifications criteria (ICDAS and CAST), the importance of the early diagnosis of caries lesions and the clinical procedures for treatment in MID.

A evolução dos preparos de classe II com a introdução de novos materiais e a conscientização da importância da preservação de estrutura dental sadia são abordadas nos preparos do tipo Almqvist, Roggenkamp e túnel, em que se observa a necessidade de menor desgaste da estrutura dentária, com aumento da resistência à fratura, melhor estética e melhor retençãoDevelopments in preparation of class II cavities with the introduction of new materials and awareness of the importance of preservation of a sound dental structure are broached in preparations of the type Almqvist, Roggenkamp and tunnel, where the need for less wear of the dental structure was observed with an increase in fracture strength, better aesthetics, and better retention

A evolução dos preparos de classe II com a introdução de novos materiais e a conscientização da importância da preservação de estrutura dental sadia são abordadas nos preparos do tipo Almqvist, Roggenkamp e túnel, em que se observa a necessidade de menor desgaste da estrutura dentária, com aumento da resistência à fratura, melhor estética e melhor retenção Developments in preparation of class II cavities with the introduction of new materials and awareness of the importance of preservation of a sound dental structure are broached in preparations of the type Almqvist, Roggenkamp and tunnel, where the need for less wear of the dental structure was observed with an increase in fracture strength, better aesthetics, and better retention