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The correct values are: For E121F SB 3 sb : 2.29 Å, 239.086 N/M, and 462.16 cm SP -1 sp ; For E121Cl SB 3 sb : 2.80 Å, 162.08 N/M, and 278.56 cm SP -1 sp ; For E121Br SB 3 sb : 2.96 Å, 137.55 N/M, and 170.93 cm SP -1 sp . In addition, the correct value for E121Cl SB 3 sb 's force constant for DC + Gaunt hamiltonian is 159.5 N/M (it was misprinted). Due to a mistake, data used for fitting the X2C spin-free results presented for E121F SB 3 sb , E121Cl SB 3 sb , and E121Br SB 3 sb in Table 1 were not correct. [Extracted from the article]

Copyright of Ciencia, Cuidado e Saude is the property of Universidade Estadual de Maringa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives: The aim of this clinical study was to evaluate the performance of restorations for non-carious cervical lesions performed with a two-step etch-and-rinse or with a two-step self-etch adhesive.Materials and Methods: The teeth to be restored (15 patients, N = 90 restorations) were randomly assigned into 3 groups (n = 30), according to the adhesive system: group 1 (G1): Peak LC Bond; group 2 (G2): Clearfil Protect Bond; and group 3 (G3): prior selective acid etching of the enamel margins before bonding with Clearfil Protect Bond. The NCCLs were restored with Amelogen Plus composite resin. Two calibrated examiners evaluated the restorations using modified US Public Health Service criteria. The data of retention, marginal integrity, and marginal discoloration were analyzed using the Kruskal-Wallis and Wilcoxon tests.Results: There were no significant differences in clinical performance among the groups for the variables: retention, marginal integrity, and marginal discoloration after 1 year and 2 years. The alpha rates after 2 years were: 93.3% for G1 and 96.7% for G2 and G3 for retention; 93.3%, 100%, and 90% for G1, G2, and G3 for marginal discoloration; 86.7%, 96.7%, and 90% for G1, G2, and G3 for marginal integrity, respectively.Conclusions: The adhesives presented similar clinical performance at the end of 2 years. Also, the prior etching with phosphoric acid did not significantly improve the clinical performance of self-etch adhesive. [ABSTRACT FROM AUTHOR]

Copyright of Universidade Estadual Paulista. Revista de Odontologia is the property of Universidade Estadual Paulista. Revista de Odontologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lutas Sociais is the property of Nucleo de Estudos de Ideolgias e Lutas Sociais (NEILS) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective. This study aimed to investigate the surface roughness of composite resins subjected to thermal cycles procedure. Materials and methods. Two microfill, four microhybrid and four nanofill composites were used. The surface roughness (Ra) was initially measured in a profilometer using a cut-off 0f 0.25 mm, after 3000 and 10,000 thermal cycles. Data were subjected to ANOVA and Fischer's test ( α = 0.05). Results. Overall, 3000 thermal cycles increased the surface roughness values for all materials and there was a trend in all groups to decrease the roughness after 10,000 thermal cycles. Conclusions. The composition of material, including the type of organic matrix, could be more relevant to roughness maintenance over time than the general behavior of composites based on particles fillers. The maintenance of smooth surface in resin-based composite restorations is totally dependent of organic composition of the material. [ABSTRACT FROM AUTHOR]

This study's aim was to evaluate the degradation rate of hydrogen peroxide (H2O2) and to quantify its penetration in tooth structure, considering the residence time of bleaching products on the dental enamel. For this study, bovine teeth were randomly divided according to the bleaching product received: Opalescence Xtra Boost 38%, White Gold Office 35%, Whiteness HP Blue 35%, Whiteness HP Maxx 35%, and Lase Peroxide Sensy 35%. To analyze the degradation of H2O2, the titration of bleaching agents with potassium permanganate was used, while the penetration of H2O2 was measured via spectrophotometric analysis of the acetate buffer solution, collected from the artificial pulp chamber. The analyses were performed immediately as well as 15 minutes, 30 minutes, and 45 minutes after product application. The data of degradation rate of H2O2 were submitted to analysis of variance (ANOVA) and Tukey tests, while ANOVA and Fisher tests were used for the quantification of H2O2, at the 5% level. The results showed that all products significantly reduced the concentration of H2O2 activates at the end of 45 minutes. It was also verified that the penetration of H2O2 was enhanced by increasing the residence time of the product on the tooth surface. It was concluded that the bleaching gels retained substantial concentrations of H2O2 after 45 minutes of application, and penetration of H2O2 in the dental structure is time-dependent. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Agricultural Sciences / Revista Brasileira de Ciências Agrárias is the property of Universidade Federal Rural de Pernambuco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this study was to assess the influence of light-curing time on the nanohardness (H) and reduced elastic modulus (Er) of components (underlying dentin, hybrid layer, adhesive, and composite) of methacrylate- and silorane-based restorations after 24 hours and six months of storage. Class II slot preparations were carried out in human molars (n=3) and restored with methacrylate (Clearfil SE Bond [Kuraray] + Filtek Z250 [3M ESPE]) or silorane (LS restorative system [3M ESPE]) restorative systems and light-cured using light-emitting diode at 1390 mW/cm² for the recommended manufacturers' time or double time. Restorations were sectioned, and bonded dentin-resin interfaces were embedded in epoxy resin and polished for evaluation with a Berkovich fluid cell tip (TI 700 Ubi-1 nanoindenter, Hysitron). Data were statistically analyzed by analysis of variance and Tukey's test (alpha=0.05). Overall, the H and Er values were higher for methacrylate-based restorations than for silorane materials (p=0.05), an increase in curing time did not improve the H and Er of the bonded interface components of either material (p>0.05), and aging significantly decreased the mechanical properties of interface components of both resin-based restorative systems (p=0.05). In general, nanomechanical properties decreased after six months of storage, the methacrylate restorative system exhibited higher H and Er than silorane, and light-curing time did not influence the properties tested. [ABSTRACT FROM AUTHOR]

Copyright of Revista Dental Press de Estética is the property of Dental Press International and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Dental Press de Estética is the property of Dental Press International and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study evaluated the effect of heat treatment on CrNi stainless steel orthodontic archwires. Half of forty archwires of each thickness – 0.014” (0.35 mm), 0.016” (0.40 mm), 0.018” (0.45 mm) and 0.020” (0.50 mm) (totalling 160 archwires) – were subjected to heat treatment while the remainder were not. All of the archwires had their individual thickness measured in the anterior and posterior regions using AutoCad 2000 software before and after compressive and tensile strength testing. The data was statistically analysed utilising multivariance ANOVA at a 5% significance level. All archwires without heat treatment that were subjected to tensile strength testing presented with anterior opening, which was more accentuated in the 0.020” archwires. In the posterior region, the opening produced by the tensile force was more accentuated in the archwires without heat treatment. There was greater stability in the thermally treated archwires, especially those subjected to tensile strength testing, which indicates that the heat treatment of orthodontic archwires establishes a favourable and indispensable condition to preserve the intercanine width. [ABSTRACT FROM AUTHOR]

Background: Data on stress distribution in tooth-restoration interface with different ceramic restorative materials are limited. The aim of this chapter was to assess the stress distribution in the interface of ceramic restorations with laminate veneer or full-coverage crown with two different materials (lithium dissilicate and densely sintered aluminum oxide) under different loading areas through finite element analysis. Materials and Methods. Six two-dimensional finite element models were fabricated with different restorations on natural tooth: laminate veneer (IPS Empress, IPS Empress Esthetic and Procera AllCeram) or full-coverage crown (IPS e.max Press and Procera AllCeram). Two different loading areas (L) (50N) were also determined: palatal surface at 45° in relation to the long axis of tooth (L1) and perpendicular to the incisal edge (L2). A model with higid natural tooth was used as control, von Mises equivalent stress (σmax) and nlaxiinum principal stress (σmax) were obtained on Ansys software. Results. The presence of ceramic restoration increased σmax and σmax in the adhesive interface, mainly for the aluminum oxide (Procera AllCeram system) restorations. The full-coverage crowns generated higher stress in the adhesive interface under L1 while the same result was observed for the laminate veneers under L2. Conclusions: Lithium dissilicate and densely sintered aluminum oxide restorations exhibit different behavior due to different mechanical properties and loading conditions. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the influence of loading on a maxillary central incisor with the periodontal ligament (PDL) represented by 2D elastic beam elements using a 2D finite element analysis. Two models (M) were built varying the PDL representation: Mh (homogeneous PDL) and Mht (heterogeneous PDL with beam3 elements). Stress and displacements were determined for three loading conditions (L): Ll, lingual face loading at 45° with the tooth long axis; Li, perpendicular to the incisal edge; and Lip, on the incisal edge, parallel to the tooth long axis. Evaluation was performed on ANSYS software. Lip provided lower stress variation on the tooth and support structures when compared to Ll and Li. PDL's influence on stress values was lower for Lip. Oblique loading showed stress and displacement not observed in parallel loading condition through PDL's heterogeneous representation and it is probably incompatible with the in vivo condition. [ABSTRACT FROM AUTHOR]

doi:10.1111/j.1741-2358.2009.00300.x Colonisation of soft lining materials by micro-organisms Objective: This study evaluated the in vitro adherence of pathogenic micro-organisms, Candida albicans, Staphylococcus aureus and Pseudomonas aeruginosa, to soft lining materials and their inhibitory effect on these micro-organisms. Materials and Methods: To measure adherence, specimens of Molloplast B and Ufi Gel P were inoculated [107 colony-forming units per millimetre (cfu/ml)] with TSB media containing the micro-organisms. To determine the number of micro-organisms in the 10−2–10−5 dilutions, 25 μl of the suspension were transferred to plates of selective media. Colony counts of each specimen were quantified (cfu/ml). The surface roughness was measured with a perfilometer to assess the relationship between the adherence of micro-organisms and surface roughness of each material. For the inhibition test, specimens of materials were placed in agar plates inoculated individually with the micro-organisms. After 48 h, the inhibition zones around the specimens were measured. Results: None of the materials exhibited inhibition zones. The number of cfu/ml of S. aureus and P. aeruginosa were significantly greater than C. albicans for both materials. The Ufi Gel P exhibited greater adherence of C. albicans than Molloplast B. No correlation was observed between the adherence of micro-organisms and surface roughness. Conclusion: The surface roughness of the materials is not the only factor governing micro-organism adherence. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to compare splinting techniques for impression copings of osseointegrated implants with different angulations. Materials and Methods: Replicas (N = 24) of a metal matrix (control) containing two implants at 90° and 65° in relation to the horizontal surface were obtained by using four impression techniques: Technique 1 (T1), direct technique with square copings without union in open trays; Technique 2 (T2), square copings splinted with dental floss and autopolymerizing acrylic resin; Technique 3 (T3),square copings splinted with dental floss and autopolymerizing acrylic resin, sectioned and splinted again with autopolymerizing acrylic resin; Technique 4 (T4), square copings splinted with prefabricated acrylic resin bar. The impression material was polyether. The replicas were individually scanned to capture the images, which were assessed in a graphic computation program. The program allowed the angulation between the bases of the replicas and the reading screws to be measured. The images of the replicas were compared with the matrix image (control), and the differences in angulations from the control image were calculated. The analysis of variance and the Tukey test for comparisons ( p < 0.05) were used for statistical analysis. Results: All groups showed significant differences in the implant angulations in comparison with the control group ( p < 0.05). Group T1 showed the highest difference (1.019°) followed by groups T2 (0.747°), T3 (0.516°), and T4 (0.325°), which showed the lowest angular alteration compared to the control group. There were significant differences between inclined and straight implants in all the groups, except in group T4. Conclusions: Based on the results, the splinting of pick-up impression copings is indicated for osseointegrated implant impressions. The square copings splinted with a prefabricated acrylic resin bar presented the best results among the pick-up impression techniques evaluated in this study. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to verify the influence of surface sealants and dentin adhesive systems on the microleakage of composite restorations. Methods: Class V cavities were made on the buccal faces of 100 permanent third molars and restored with Z250. After 24 hours, they were submitted to polishing and finishing processes. The teeth were divided into groups according to the sealant agent: group 1-SingleBond; group 2-Opti Bond Solo Plus; group 3-Fortify; group 4-Fortify Plus; and group 5-control without sealant. The analysis of immediate micro leakage was perform edin 10 restorations from each group, soon after the sealing. The other 10 specimens from each group were submitted to tooth-brushing and thermal cycles. The teeth were isolated and immersed in 2% methylene blue solution, washed in tap water, and sectioned in the buccolingual direction. The percentage of marginal leakage was calculated using an image analysis program, and results were submitted to analysis of variance and Tukey's test. Results: All the sealed groups demonstrated lower microleakage values compared to the control group. Group 3, sealed with Fortify, presented the lowest mean micro leakage values. Conclusion: The application of surface sealants effectively decreased the microleakage incomposite resin restorations. [ABSTRACT FROM AUTHOR]

Purpose: To verify the effect of surface penetrating sealant on the toughness of posterior resin-based composites before and after mechanical toothbrushing. Materials and Methods: 10 specimens of four different composites (Alert, Definite, Z100 and Prodigy Condensable) were made using a metal matrix (height 2 mm and diameter 4 mm). After 24 hours, the specimens were polished using Sof-Lex discs in sequence: coarse, medium, fine and superfine, each for 40 seconds and, immediately, one of the surfaces was covered with Protect-It surface sealant. All the specimens were examined with a profilometer to measure the initial surface roughness before mechanical toothbrushing at a constant speed of 250 strokes/minute with a total of 30,000 cycles, using a toothbrush and dentifrice containing calcium carbonate as abrasive, under a load of 200g. After toothbrushing the surface roughness was measured once again. The data were analyzed with ANOVA and the Tukey test at a 95% confidence level. Results: Mechanical toothbrushing increased the surface roughness of all the composites studied (Alert: 0.7303 ± 0.0942 µm; Definite: 0.4961 ± 0.1255 µm; Z100: 0.3428 ± 0.0841 µm), with the exception of Prodigy Condensable (0.2782 ± 0.0678 µm) (P> 0.05). The surface penetrating sealant effectively decreased the surface roughness for Alert (0.5435 ± 0.2182 µm) and Definite (0.2956 ± 0.0368 µm) (P< 0.05), but had no effect upon Z100 (0.3331 ± 0.0565 µm) and Prodigy Condensable (0.2760 ± 0.0920 µm) as these have smaller filler sizes than the other composites tested (P> 0.05). [ABSTRACT FROM AUTHOR]

Objective: to compare the indicators of access to and use of health services by community elderly people according to different levels of social vulnerability. Methods: cross-sectional study carried out with 805 elderly people. A questionnaire from the National Household Sample Survey was used to measure indicators of access to and use of health services; and Social Vulnerability Index to assess social vulnerability. Results: elderly people living in areas of high/very high vulnerability had a higher proportion of negative outcomes in terms of bond with the service (p <0.001), access to medication (p <0.001) and access to the dentist (p < 0.001). Most elderly people living in more vulnerable areas used the health center (54.2%); most residents in low vulnerability areas sought private care (47.2%) (p <0.001). Conclusion: elderly people living in areas of greater social vulnerability had worse results related to indicators of access to health services, although they use the public service more often. [ABSTRACT FROM AUTHOR]

The loss of energy by heat is a common problem in almost all areas of industry, and heat pipes are essential to increase efficiency and reduce energy waste. However, in many cases, they have complex theoretical equations with high percentages of error, limiting their development and causing dependence on empirical methods that generate a waste of time and material, resulting in significant expenses and reducing the viability of their use. Thus, Artificial Neural Networks (ANNs) can be an excellent option to facilitate the construction and development of heat pipes without knowledge of the complex theory behind the problem. This investigation uses experimental data from previous studies to evaluate the ability of three different ANNs to predict the thermal performance of heat pipes with different capillary structures, each of them in various configurations of the slope, filling ratio, and heat load. The goal is to investigate results in as many different scenarios as possible to clearly understand the networks' capacity for modeling heat pipes and their operating parameters. We chose two classic ANNs (the most used, Multilayer Perceptron (MLP) network, and the Radial Basis Function (RBF) network) and the Extreme Learning Machine (ELM), which has not yet been applied to heat pipes studies. The ELM is an Unorganized Machine with a fast training process and a simple codification. The ANN results were very close to the experimental ones, showing that ANNs can successfully simulate the thermal performance of heat pipes. Based on the RMSE (error metric being reduced during the training step), the ELM presented the best results (RMSE = 0.384), followed by MLP (RMSE = 0.409), proving their capacity to generalize the problem. These results show the importance of applying different ANNs to evaluate the system deeply. Using ANNs in developing heat pipes is an excellent option for accelerating and improving the project phase, reducing material loss, time, and other resources. [ABSTRACT FROM AUTHOR]

Malignant melanoma accounts for around 5% of all malignant skin tumors. It is considered one of the most aggressive neoplasms due to its high metastasizing capacity. The most common sites of metastasis are peri-tumor lymph nodes, lung, brain and liver. The digestive tract is not a common site of metastasis. When involved, the small intestine is the organ most commonly affected. The stomach is a rare site of metastasis, found in only 7% percent of the cases. We report a case of a 72-year-old patient with a history of malignant melanoma who presented with acute epigastric pain. Enterotomography, upper endoscopy and additional biopsies confirmed the diagnosis of gastric metastases. [ABSTRACT FROM AUTHOR]

• Curcumin at 1000 mg/L influenced bond strength of glass-fiber posts to root dentin. • MB PS in different concentrations, activated or not, did not influence bond strength. • There was no difference among the root thirds for bond strength for each group. • Adhesive failure was prevalent for curcumin PS activated at both concentrations. Although photodynamic therapy associated with photosensitizers can promote microbial reduction, studies evaluating the consequences of two photodynamic therapy sessions associated with different photosensitizers on the bond strength of glass-fiber posts to endodontically treated intraradicular dentin are scarce. This in vitro study aimed to investigate the influence of two photodynamic therapy sessions using methylene blue or curcumin photosensitizers on the bond strength of glass-fiber posts to intraradicular dentin in different root thirds. Seventy-two teeth were divided into 9 experimental groups according to photosensitizer type, concentration and light-activation: Control - deionized water; Methylene blue 50 mg/L; Methylene blue 50 mg/L + laser; Methylene blue 100 mg/L; Methylene blue 100 mg/L + laser; Curcumin 500 mg/L; Curcumin 500 mg/L + LED; Curcumin 1000 mg/L; and Curcumin 1000 mg/L + LED. Push-out bond strength of the fiber posts to endodontically treated dentin was evaluated using a universal test machine (n = 8). Bond strength data underwent Kruskal-Wallis test, followed by Dunn test for comparison between treatments, and Friedman test for comparison between thirds (α = 0.05). Illustrative scanning electron microscopy images were obtained to qualify the failure mode. Curcumin at higher concentration, activated or not by blue LED, decreased the bond strength values in the apical region when compared with the control group (P < 0.05). There was no difference between two photodynamic therapy sessions using methylene blue photosensitizer (activated or not) and the control group regardless of concentrations and root canal depth evaluated (P > 0.05). Regarding intraradicular depth, the different thirds showed no statistical difference on bond strength values (P > 0.05). All experimental groups presented predominance of mixed-type failure, excepting the methylene blue group at higher concentration activated by red laser, and the curcumin photosensitizer at both concentrations activated by blue LED. Methylene blue at a 50 mg/L concentration can be applied in two PDT sessions, after biomechanical preparation and before glass-fiber post luting, as it presents no influence on root dentin bond strength in in vitro conditions. [ABSTRACT FROM AUTHOR]

• The bleaching carried out with violet LED did not impair the resin-dentin bond strength neither the mechanical properties of the hybrid layer. • The traditional whitening treatment was more harmful to dentin collagen than the use of violet LED. • The violet LED was able to provide a whitening effect on dental substrates. The purpose of this study was to investigate the effect of a novel dental bleaching technique with Violet LED on enamel color change, bond strength and hybrid layer nanomechanical properties in resin-dentin restoration, and dentin biostability. A total of 125 bovine incisors were distributed into a control group, violet LED group (LED), and 35 % peroxide hydrogen bleaching gel (BLG) groups (n = 15). Three 45-minute sessions were performed for both bleaching procedures every week. Enamel color change (ΔE, ΔL, and Δb) was determined after every bleaching session. After color analysis, dentin was exposed for the resin-dentin bond strength analysis using microtensile test and evaluation of the nanomechanical properties at the hybrid layer (nanohardness). While half of the specimens were tested immediately, the remaining were evaluated after 10,000 thermal cycles (TC). Thirty additional teeth were used to investigate dentin ultimate tensile strength (UTS) after the bleaching treatments. UTS was evaluated before and after an enzymatic challenge. Two-way repeated measures ANOVA and Tukey's post-test were used for the statistical analysis (α = 0.05). Enamel bleaching effect was observed in the LED and BLG groups with significant alterations in the ΔE, ΔL, and Δb in the BLG group. No difference was observed in the resin-dentin bond strength among the groups (p > 0.05), however, TC negatively affected the bond strength values for all the groups. Nanomechanical properties ​​remained unchanged when comparing immediate and after TC results (p > 0.05). Bleaching with BLG reduced significantly the dentin UTS, while all groups showed major decrease in UTS after the enzymatic challenge. Although violet LED was able to promote a bleaching effect, less color changes was observed when compared to BLG. None of the bleaching techniques effected the resin-bond strength or the nanomechanics of the hybrid layer. Violet LED did negatively effect dentin biostability as observed for BLG and it may promote less changes to the organic content of dentin. [ABSTRACT FROM AUTHOR]

This article aimed to report the experience of nursing students in the planning and implementation of an intervention to sensitize primary health care professionals about the practice of user embracement. For the development of the intervention, the problematization methodology supported by the Maguerez' Arch was applied. From the observation of reality, the theme user embracement was listed and the other stages performed. In the application to reality, four meetings with the team were held in order to sensitize them to look at the work process. Furthermore, the academics developed a critical reflection, being transformative for the formation. It is concluded that the reported experience demonstrated the importance of the adoption of strategies, such as the Arc, that favor the promotion of improvements in the work process in services, especially aspects that interfere in the quality of care and satisfaction of users, such as user embracement. [ABSTRACT FROM AUTHOR]

• Color analysis and dental sensitivity of VL with carbamide peroxide 10 % were evaluated. • The emission of light at a wavelength of 405-410 nm, coincides with the absorption peak of the chromophore molecules. • The combination of home treatment with irradiation with VL enhances the final result, but increases sensitivity. To evaluate the bleaching efficacy and post-operative sensitivity of 10 % carbamide peroxide (PC) with or without violet LED (VL). Thirty patients were selected and were instructed to perform home bleaching treatment using PC 10 %, for 8 h daily, for 21 days. All patients underwent in-office irradiation of only one hemiarch with VL for 30 min, twice per week for three weeks, totaling six clinical sessions of irradiation. The treatment used for each hemiarch was determined randomly. The analyses were performed at the initial time and 7, 14, and 21 days after the start of treatment and 7 and 14 days after the end of the bleaching treatment. For color analysis, digital spectrophotometry was done using the Visual Analog Scale and cold detection was performed using the thermo-sensory analysis II (TSA II) equipment. The ANOVA-two way with repeated measures and the Tukey test (α = 0.05) were used for the color and cold sensitivity analysis. On analyzing the color change, it was observed that the hemiarch that was irradiated with VL presented the highest values compared with the side that did not receive irradiation. Regarding tooth sensitivity, there was no report of any patient experiencing discomfort during the bleaching protocol. Analysis of the dental thermal sensation threshold showed that the use of VL made the teeth more sensitive. It can be concluded that the VL provided a positive effect on color alteration when used in conjunction with 10 % PC. However, the use of this new protocol made the teeth more sensitive. [ABSTRACT FROM AUTHOR]

• MB in different concentrations, with or without laser action, did not cause significant differences in MH and Eit values. • MB at 100 mg/L with laser activation in the middle region of intraradicular dentin promoted lower bond strength values. • There was no difference among the intraradicular thirds for MH, Eit, and bond strength values. There are few studies on the influence of methylene blue as a photosensitiser on the mechanical properties and adhesion of glass-fiber posts to intraradicular dentin. Thus, this in vitro study aimed to evaluate the influence of photodynamic therapy with a methylene blue photosensitizer on the Martens hardness, elastic modulus, and bond strength of glass-fiber posts in different thirds of intraradicular dentin. Eighty bovine teeth were divided into the following five groups: a control using deionized water, and four other groups according to the methylene blue concentration (50 mg/L or 100 mg/L) and substrate treatment (with or without red laser action). Ultramicrohardness test was used to evaluate the mechanical properties in different regions of the root dentin (n = 8). Push-out analysis was evaluated using a universal testing machine (n = 8). Data were subjected to the Kruskal–Wallis test, followed by Dunn's test for comparing groups, and the Friedman test for comparing thirds (α = 0.05). Representative scanning electron microscopy images were obtained. In general, methylene blue in distinct concentrations, with or without laser action, did not cause differences in the mechanical properties or bond strength in different regions of root dentin (P > 0.05). Methylene blue at a higher concentration, activated with laser, produced lower bond strength values in the middle third of the root canal (P < 0.05). Methylene blue at 50 mg/L had no influence on the mechanical properties of the bovine tooth and the bond strength of the glass-fiber posts to intraradicular dentin. [ABSTRACT FROM AUTHOR]