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Introduction: The decalcification protocol of dentin surface with sodium hypochlorite removes the exposed collagen fibrils and could improve the longevity of the bonding interface. This study evaluated the influence of collagen removal with 10% sodium hypochlorite (10% NaOCl) on the longitudinal shear bond strength (SBS) of adhesives to dentin., Materials and Methods: Seventy-two extracted human molars were sectioned and the buccal and lingual surfaces were flattened and acid etched with 37% phosphoric acid for 15 seconds. The specimens were divided into six groups (n = 12 teeth - 24 sections), according to adhesive and collagen removal protocol: group 1: UNO Dentastic; group 2: Prime and Bond NT; group 3: Single Bond; group 4: 10% NaOCl + UNO Dentastic; group 5: 10% NaOCl + Prime and Bond NT; group 6: 10% NaOCl + Single Bond. Composite Z100 buildup was prepared, and the SBS test was assessed after 24 hours and 1 year. Data were submitted to three-way analysis of variance (ANOVA) and Tukey tests (p < 0.05)., Results: The mean values (MPa) were for 24 hours: G1: 22.45 B ; G2: 7.90 DE ; G3: 12.56 CD ; G4: 19.85 BC ; G5: 33.73 A ; G6: 20.77 B ; and for 1 year: G1: 2.43 E ; G2: 2.26 E ; G3: 4.3 DE ; G4: 18.79 BC ; G5: 26.49 AB ; G6: 22.73 B ., Conclusion: Dentin deproteinization treatment with 10% NaOCI influenced the SBS compared with conventional treatment. The negative influence on SBS detected for conventional groups at 1-year interval was not detected for deproteinized groups., Clinical Relevance: The longevity of hybrid layer is critical due to the hydrolysis process at the adhesive interface over time. The use of 10% NaOCl deproteinization protocol might improve the longevity of bonding in adhesive restorations.

Aim: The aim of this study was to compare the microtensile bond strength of three adhesive systems, using different methods of dentin preparation., Materials and Methods: A hundred and eight bovine teeth were used. The dentin from buccal face was exposed and prepared with three different methods, divided in 3 groups: Group 1 (DT)- diamond tip on a high-speed handpiece; Group 2 (CVD)-CVD tip on a ultrasonic handpiece; Group 3 (LA)-Er: YAG laser. The teeth were divided into 3 subgroups, according adhesive systems used: Subgroup 1-Adper Single Bond Plus/3M ESPE (SB) total-etch adhesive; Subgroup 2-Adper Scotchbond SE/3M ESPE (AS) selfetching adhesive; Subgroup 3-Clearfil SE Bond/Kuraray (CS) selfetching adhesive. Blocks of composite (Filtek Z250-3M ESPE) 4 mm high were built up and specimens were stored in deionized water for 24 hours at 37°C. Serial mesiodistal and buccolingual cuts were made and stick-like specimens were obtained, with transversal section of 1.0 mm(2). The samples were submitted to microtensile test at 1 mm/min and load of 10 kg in a universal testing machine. Data (MPa) were subjected to ANOVA and Tukey's tests (p < 0.05)., Results and Conclusion: Surface treatment with Diamond or CVD tips associated with Clearfil SE Bond adhesive produced significantly lower bond strength values compared to other groups. Surface treatment with Er: YAG laser associated with Single Bond Plus or Clearfil SE Bond adhesives and surface treatment with CVD tip associated with Adper Scotchbond SE adhesive produced significantly lower bond strength values compared to surface treatment with diamond or CVD tips associated with Single Bond Plus or Adper Scotchbond SE adhesives., Clinical Significance: Interactions between laser and the CVD tip technologies and the different adhesive systems can produce a satisfactory bonding strength result, so that these associations may be beneficial and enhance the clinical outcomes.

Aim: This study evaluated the prevalence of the chewing side preference (CSP) in the deciduous, mixed and permanent dentitions., Materials and Methods: Three-hundred subjects were divided in three groups (n = 100): Group 1 - children with deciduous dentition; group 2-children with mixed dentition; group 3 - subjects with permanent dentition. The CSP was determined using a direct method (visual observation) developed by McDonnell et al. (2004). Descriptive statistic was used to observe the prevalence of CSP. The Pearson's Chi-square was used to investigate signicant associations between gender, presence of CSP and preferred side (right/left)., Results and Conclusion: Eighty-seven percent of group 1 had a CSP. Eighty-two percent of group 2 had a CSP. Seventy-six percent of group 3 had a CSP. There was no statistically significant association between presence of CSP and gender in all groups. There was no statistically significant association between preferred side (right/left) and gender in all groups., Clinical Significance: There is a higher prevalence of subjects in deciduous, mixed and permanent dentition that presented chewing side preference. The early diagnosis of the presence of chewing side preference can prevent the unilateral chewing pattern with prophylactic therapy applied to the first teeth (deciduous).

Objectives: This study aimed to measure pH changes during 14 days intracoronal bleaching with hydrogen peroxide/sodium perborate and carbamide peroxide/sodium perborate., Materials and Methods: Twenty patients presenting endodontically treated central maxillary incisors with color alterations were divided in two groups (n = 10): Group CP + SP: 37% carbamide peroxide + sodium perborate paste; Group HP + SP: 30% hydrogen peroxide + sodium perborate paste. The pH values were measured using a digital microprocessor at different times: Baseline, 2, 7 and 14 days. Data were analyzed with two-way ANOVA followed by Tukey's test (α = 0.05)., Results: ANOVA showed p < 0.00 which indicated significant difference between the groups. The mean values (± sd) and the results of the Tukey´s test were: HP + SP/14 days-7.98 (±0.58)a; HP + SP/7 days-8.59 (±0.18)b; HP + SP/2 days- 8.83 (±0.32)bc; HP + SP/Baseline-8.83 (±0.01)bc; CP + SP/ Baseline-8.89 (±0.01)bc; CP + SP/14 days-9.11 (±0.58)cd; CP + SP/7 days-9.54 (±0.16)de; CP + SP/2 days-9.66 (±0.08) de. The group HP + SP resulted in significantly lower pH values compared with group CP + SP., Conclusion: It can be concluded that both associations showed alkaline pH values; however, there was significant reduction in the pH values of the 30% hydrogen peroxide associated with sodium perborate after 14 days., Clinical Significance: The association of hydrogen peroxide and carbamide peroxide with sodium perborate paste presented alkaline characteristics during the 14-day evaluated period. Thus, regarding pH changes, both associations can be considered safe as intracoronal bleaching agents.