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This study evaluated the effects of Erbium-doped yttrium aluminium garnet (Er:YAG) laser settings and dentin bonding agents on ultramorphological characteristics of resin-laser-irradiated dentin interfaces and dentin bond strength (BS) of these adhesive systems. Additionally, dentin depth affected by Er:YAG laser irradiations was measured. The experiments were performed on occlusal dentin surfaces of third molars that were flattened with 600-grit SiC sandpaper. Treated-dentin with laser settings (250 mJ/4 Hz and 160 mJ/10 Hz) were the experimental groups, while SiC abraded dentin was the control. These three dentin treatments and three adhesives (two self-etchings and one etch-&-rinse adhesive) formed nine groups for the ultramorphology of laser-ablated dentin-adhesives interfacial analysis, using a transmission electron microscope (TEM). For BS (n = 8), the same nine groups were tested with addition of the two evaluation times (24 h after sample preparation or 1 year). The depths of Er:YAG laser effects into the dentin were measured using a TEM (n = 10). Ablated-dentin depth and BS data were analyzed by one- and three-way ANOVA, respectively, and Tukey's test (α = 0.05). Hybrid layer formation was only observed for controls, while for laser-treated dentin, adhesives were bonded to dentin with resin tags formation. Laser settings reduced the BS for all adhesives at 24 h, while at 1 year, etch-&-rinse adhesive presented the highest BS, regardless treatment (control or laser settings). Dentin depth affected by laser settings was similar. The laser irradiation altered the bonding mechanism of the adhesives to dentin and reduced the BS for self-etching adhesives. Etch-&-rinse adhesive yielded the highest BS at 1 year. Laser settings similarly affected the dentin in depth. HIGHLIGHTS: Er:YAG laser irradiation settings produced similar effects on depth and bond strength to dentin. The etch-&-rinse adhesive yielded the highest dentin bond strength regardless of the type of dentin treatment at 1 year.

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This systematic review assessed the literature to evaluate the efficiency of polymerization of bulk-fill composite resins at 4 mm restoration depth. PubMed, Cochrane, Scopus and Web of Science databases were searched with no restrictions on year, publication status, or article's language. Selection criteria included studies that evaluated bulk-fill composite resin when inserted in a minimum thickness of 4 mm, followed by curing according to the manufacturers' instructions; presented sound statistical data; and comparison with a control group and/or a reference measurement of quality of polymerization. The evidence level was evaluated by qualitative scoring system and classified as high-, moderate- and low- evidence level. A total of 534 articles were retrieved in the initial search. After the review process, only 10 full-text articles met the inclusion criteria. Most articles included (80%) were classified as high evidence level. Among several techniques, microhardness was the most frequently method performed by the studies included in this systematic review. Irrespective to the "in vitro" method performed, bulk fill RBCs were partially likely to fulfill the important requirement regarding properly curing in 4 mm of cavity depth measured by depth of cure and / or degree of conversion. In general, low viscosities BFCs performed better regarding polymerization efficiency compared to the high viscosities BFCs.

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The effect of restoration depth on the curing time of a conventional and two bulk-fill composite resins by measuring microhardness and the respective radiosity of the bottom surface of the specimen was investigated. 1-, 3- and 5-mm thick washers were filled with Surefil SDR Flow-U (SDR), Tetric EvoCeram Bulk Fill-IVA (TEC) or Esthet-X HD-B1 (EHD), and cured with Bluephase® G2 for 40s. Additional 1-mm washers were filled with SDR, TEC or EHD, placed above the light sensor of MARC®, stacked with pre-cured 1-, 3- or 5-mm washer of respective material, and cured for 2.5~60s to mimic 2-, 4- and 6-mm thick composite curing. The sensor measured the radiosity (EB) at the bottom of specimen stacks. Vickers hardness (VH) was measured immediately at 5 locations with triplicate specimens. Nonlinear regression of VH vs EB by VH=α[1-exp(-EB/ß)] with all thickness shows that the values of α, maximum hardness, are 21.6±1.0 kg/mm2 for SDR, 38.3±0.6 kg/mm2 for TEC and 45.3±2.6 kg/mm2 for EHD, and the values of ß, rate parameter, are 0.40±0.06 J/cm2 for SDR, 0.77±0.04 J/cm2 for TEC and 0.58±0.09 J/cm2 for EHD. The radiosity of the bottom surface was calculated when the bottom surface of each material attained 80% of α of each material. The curing times for each material are in agreement with manufacturer recommendation for thickness. It is possible to estimate time needed to cure composite resin of known depth adequately by the radiosity and microhardness of the bottom surface.

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Abstract This systematic review assessed the literature to evaluate the efficiency of polymerization of bulk-fill composite resins at 4 mm restoration depth. PubMed, Cochrane, Scopus and Web of Science databases were searched with no restrictions on year, publication status, or article's language. Selection criteria included studies that evaluated bulk-fill composite resin when inserted in a minimum thickness of 4 mm, followed by curing according to the manufacturers' instructions; presented sound statistical data; and comparison with a control group and/or a reference measurement of quality of polymerization. The evidence level was evaluated by qualitative scoring system and classified as high-, moderate- and low- evidence level. A total of 534 articles were retrieved in the initial search. After the review process, only 10 full-text articles met the inclusion criteria. Most articles included (80%) were classified as high evidence level. Among several techniques, microhardness was the most frequently method performed by the studies included in this systematic review. Irrespective to the "in vitro" method performed, bulk fill RBCs were partially likely to fulfill the important requirement regarding properly curing in 4 mm of cavity depth measured by depth of cure and / or degree of conversion. In general, low viscosities BFCs performed better regarding polymerization efficiency compared to the high viscosities BFCs.

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OBJECTIVES: This study aimed to evaluate the ultramorphological characteristics of tooth-resin interfaces and the bond strength (BS) of multimode adhesive systems to enamel and dentin. METHODS: Multimode adhesives (Scotchbond Universal (SBU) and All-Bond Universal) were tested in both self-etch and etch-and-rinse modes and compared to control groups (Optibond FL and Clearfil SE Bond (CSB)). Adhesives were applied to human molars and composite blocks were incrementally built up. Teeth were sectioned to obtain specimens for microtensile BS and TEM analysis. Specimens were tested after storage for either 24 h or 1 year. SEM analyses were performed to classify the failure pattern of beam specimens after BS testing. RESULTS: Etching increased the enamel BS of multimode adhesives; however, BS decreased after storage for 1 year. No significant differences in dentin BS were noted between multimode and control in either evaluation period. Storage for 1 year only reduced the dentin BS for SBU in self-etch mode. TEM analysis identified hybridization and interaction zones in dentin and enamel for all adhesives. Silver impregnation was detected on dentin-resin interfaces after storage of specimens for 1 year only with the SBU and CSB. CONCLUSIONS: Storage for 1 year reduced enamel BS when adhesives are applied on etched surface; however, BS of multimode adhesives did not differ from those of the control group. In dentin, no significant difference was noted between the multimode and control group adhesives, regardless of etching mode. CLINICAL RELEVANCE: In general, multimode adhesives showed similar behavior when compared to traditional adhesive techniques. Multimode adhesives are one-step self-etching adhesives that can also be used after enamel/dentin phosphoric acid etching, but each product may work better in specific conditions.

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Abstract The effect of restoration depth on the curing time of a conventional and two bulk-fill composite resins by measuring microhardness and the respective radiosity of the bottom surface of the specimen was investigated. 1-, 3- and 5-mm thick washers were filled with Surefil SDR Flow-U (SDR), Tetric EvoCeram Bulk Fill-IVA (TEC) or Esthet-X HD-B1 (EHD), and cured with Bluephase® G2 for 40s. Additional 1-mm washers were filled with SDR, TEC or EHD, placed above the light sensor of MARC®, stacked with pre-cured 1-, 3- or 5-mm washer of respective material, and cured for 2.5~60s to mimic 2-, 4- and 6-mm thick composite curing. The sensor measured the radiosity (EB) at the bottom of specimen stacks. Vickers hardness (VH) was measured immediately at 5 locations with triplicate specimens. Nonlinear regression of VH vs EB by VH=α[1-exp(-EB/β)] with all thickness shows that the values of α, maximum hardness, are 21.6±1.0 kg/mm2 for SDR, 38.3±0.6 kg/mm2 for TEC and 45.3±2.6 kg/mm2 for EHD, and the values of β, rate parameter, are 0.40±0.06 J/cm2 for SDR, 0.77±0.04 J/cm2 for TEC and 0.58±0.09 J/cm2 for EHD. The radiosity of the bottom surface was calculated when the bottom surface of each material attained 80% of α of each material. The curing times for each material are in agreement with manufacturer recommendation for thickness. It is possible to estimate time needed to cure composite resin of known depth adequately by the radiosity and microhardness of the bottom surface.

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Novas tecnologias aliadas a novos materiais vêm de encontro à filosofia de facilitar a clínica diária, diminuindo o número de passos, consequentemente diminuindo a chance de erro se utilizando menos tempo clínico para obter bons resultados. Paciente do gênero masculino,38 anos, apresentava uma restauração classe II OD deficiente no elemento 36. Foi realizado oexame clínico, radiográfico e seleção de cor. Sobre isolamento absoluto, a restauração antiga e a lesão de cárie foram removidas. Para a realização da nova restauração foi utilizado um sistema de matriz seccional e uma resina composta de baixa tensão de contração de polimerização e baixa viscosidade com a técnica bulk-fill, seguida por uma resina convencional como é preconizado.Pode-se observar que a técnica bulk-fill é bastante simples quando comparada à técnica incremental tradicional e aliada ao uso do sistema de matrizes seccionais otimizam ainda mais o dia-a-dia na clínica.

New technologies associated with new materials have been introduced to facilitate the dailyclinical procedures, reducing the number of steps, thus reducing the chance of mistakes andchair time for clinical procedures. Male patient, 38 years old, had a deficient OD class II restorationin the lower left first molar. Clinical examination, x-ray and color selection were performed.Using rubber dam isolation, the old restoration and caries were removed. For the new restorationa sectional matrix system and a low-stress flowable bulk-fill composite were used, followedby a conventional nanohybrid composite as recommended. It can be seen that the bulk-fill techniqueis quite simple compared to the traditional incremental technique and combined withthe system of sectional matrix system further optimize the restorative procedures.

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OBJECTIVE: The aim of this study was to evaluate the influence of cavity preparation and restorative materials containing fluorides in the prevention of secondary caries lesion development in situ. METHODS: A total of 120 blocks obtained from human teeth were divided into two groups and standardized cavities were prepared using diamond burs (DB) or Er,Cr:YSGG-laser [20 Hz, 4.0W, 55% water, 65% air (LA)]. They were divided into three subgroups according to the restorative material (n=20): glass-ionomer cement (GI), resin modified glass-ionomer (RM) or composite resin (CR). Blocks were fixed in palatal intra-oral appliances worn in situ by 20 human volunteers, who dropped 20% sucrose solution eight times daily. After 21 days, blocks were removed and restorations were cross-sectioned to evaluate microhardness [Knoop hardness number (KHN)] underneath enamel surface from 30 to 200 µm. Factors "cavity preparation," "restorative materials," and "depth" were evaluated by three way ANOVA, followed by Tukey test (p<0.05). RESULTS: The results showed lower microhardness in cavities prepared with DB than in cavities prepared with LA. At 30 µm, there were no statistical significant differences with regard to "cavity preparation" or "restorative materials" factors. In depth evaluation, the enamel microhardness progressively increased as a function of depth for the GI groups. In the groups prepared with LA at 60 µm/90 µm, there were no significant differences between GI and RM materials, whose microhardnesses were significantly higher than that of CR. CONCLUSIONS: Cavity preparation using Er,Cr:YSGG laser increases caries resistance of enamel walls, and reduce caries lesion depth development regardless of fluoride presence in the restorative material. CR showed higher caries lesion development than GI, and RM showed intermediate results.

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Objective: This study evaluated the ultimate tensile strength (UTS) and microhardness (µKH) of conventional (CO) and hybrid resin-modified glass ionomer (RM). Material and methods: Nine specimens to UTS and twelve for µKHN of glass ionomer materials were obtained using special molds. The materials were manipulated and CO groups were allowed to self-cure for five minutes and RM were subjected to light-activation as indicated by manufactures through a glass slide. All specimens were dark-stored in 100% relative humidity for 24 h. For UTS test, specimens were tested in tension in a universal testing machine (crosshead speed of 1 mm/ min) until failure. For µKHN test a Knoop diamond indenter was used to make five indentations in the upper/light irradiated surface of the specimens. UTS and µKHN data were submitted to one-way ANOVA, followed by Tukey’s test (α = 5%). Results: The results for UTS were: Ionomaster: 7.0 (± 1.6) A; Maxxion R: 8.8 (± 3.7) A Vidrion R: 8.8 (± 3.9) A; ChemFil Rock: 10.7 (± 4.6) AB; Vitremer: 13.1 (± 3.3)BC; Vitrofil R: 14.9 (± 7.8)CD; Ionoseal: 14.5 (± 8.2)CD; Resiglass: 16.3 (± 2.3)D. The results for µKH: Ionomaster: 24.3 (± 6.6)B; Maxxion R: 17.7 (± 4.7) A, Vidrion R: 31.0 (± 9.4) B; ChemFil Rock: 31.1 (± 8.5)B; Vitremer: 20.3 (± 3.3) A; Vitrofil R: 16.5 (± 5.1) A; Ionoseal: 13.1 (± 8.5) A; Resiglass: 21.6 (± 5.2) A. Conclusion: It was observed that the hybrid resin-modified ionomers generally have higher cohesive strength than conventional ones, but lower microhardness

Objetivo: Este estudo avaliou a resistência coesiva (UTS) e microdureza (μKH) de materiais ionoméricos, convencional (CO) e híbrido de ionômero de vidro modificado por resina (RM). Material e Métodos: Nove amostras para UTS e doze para μKHN de materiais ionoméricos foram preparadas utilizando matrizes especiais. Os materiais foram manipulados e grupos CO sofreram a autocura durante cinco minutos e os RM foram submetidos à ativação por luz como indicado pelos fabricantes através de uma lamínula de vidro. Todos os espécimes foram armazenados no escuro, em 100 % de umidade relativa por 24 horas. Para o teste de UTS, os espécimes foram testados em tensão numa máquina de ensaios universal (velocidade de 1 mm/min ) até a falha. Para o teste μKH um diamante penetrador tipo Knoop foi usado para fazer 5 endentações na parte superior; irradiada pela luz na superfície dos espécimes. Os dados de UTS e de μKHN foram submetidos a one-way ANOVA, seguido pelo teste de Tukey (α = 5%). Resultados: Os resultados para UTS foram: Ionomaster: 7,0 (± 1,6) A; Maxxion R: 8,8 (± 3,7) A Vidrion R: 8,8 (± 3,9) A; Chemfil Rock: 10,7 (± 4,6) AB; Vitremer: 13,1 (± 3,3)BC; Vitrofil R: 14,9 (± 7,8) CD; Ionoseal: 14,5 (± 8,2) CD; Resiglass: 16,3 (± 2,3)D. Os resultados para μKH: Ionomaster: 24,3 (± 6,6) B; Maxxion R: 17,7 (± 4,7) A, Vidrion R: 31,0 (± 9,4) B; Chemfil Rock: 31,1 (± 8,5) B; Vitremer: 20,3 (± 3,3) A; Vitrofil R: 16,5 (± 5,1) A; Ionoseal: 13,1 (± 8,5) A; Resiglass: 21,6 (± 5,2) A. Conclusão: Observou-se que os híbridos de ionômero de vidro modificados por resina geralmente têm força coesiva mais alta do que os convencionais, mas menor dureza.

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This study aimed to evaluate the effect of the previous application of a casein phosphopeptide-amorphous calcium phosphate paste (MI Paste, MI) and adhesive systems on the bond durability of a fissure sealant. Ninety-eight enamel blocks were obtained from proximal surfaces of erupted third molars. Specimens were divided into 14 groups (n = 7) according to the previous application of MI (with and without) and the adhesive systems used (no adhesive system; hydrophobic resin of a three-step etch-and-rinse adhesive system; etch-and-rinse single-bottle adhesive system; all-in-one adhesive system; two-step self-etching adhesive system; additional phosphoric acid conditioning and all-in-one adhesive system; additional phosphoric acid conditioning and two-step self-etching adhesive system). A fissure sealant (Fluroshield) was applied and photoactivated for 20 s. Beams (~0.7 mm(2)) were prepared for the microtensile bond strength test, which was executed after 24 h or 6 months of water storage. Fractured specimens were analyzed by scanning electronic microscopy. Data were analyzed by two-way ANOVA with repeated measures/Tukey's test (P < 0.05). Groups that received MI application and adhesive systems presented higher means than those groups where MI was not applied. Higher frequency of cohesive failures was observed for groups with MI. Applying a CPP-ACP containing paste on enamel before adhesive systems was an effective method to increase bond durability of the sealant tested.

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