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Objectives: The aim of this study was to evaluate the clinical performance of surface sealants associated with a bulk-fill composite in posterior restorations after 4 years., Methods: A total of 174 posterior restorations were performed on 57 participants using a self-etch adhesive system and a bulk-fill composite. The groups were then divided into the following categories: 1) without surface sealant (NoS), 2) with surface sealant Biscover (Bisco, SBi), and 3) with surface sealant Permaseal (Ultradent, SPe). Restorations were evaluated using FDI criteria at baseline and after 1 and 4 years. Statistical analysis was conducted using Kaplan-Meier survival analysis and the Chi-square test (α = 0.05)., Results: After 4 years, only one restoration was lost (1 in the NoS group). The fracture/retention rate (with 95% confidence interval) was 98% for NoS and 100% for both SBi and SPe (p = 0.76). The majority of secondary outcomes showed minor defects, with no significant differences among the groups (p > 0.05). However, significant differences were observed among the groups in terms of marginal staining and marginal adaptation (p = 0.03). In both items, twelve restorations (nine in NoS, one in SBi, and two in SPe) showed minor marginal discrepancies favoring the sealant groups (SBi and SPe)., Significance: Regardless of the use of surface sealants, the bulk-fill composite restorations showed excellent clinical performance after 4 years. However, the groups that received sealants showed better marginal adaptation and less marginal discoloration compared to those that did not receive sealants., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Purpose: The purpose of this study was to evaluate changes in calcium and phosphorus content in dental enamel when subjected to "in-office" whitening for an extended time by using a 35% hydrogen peroxide solution, with and without calcium., Materials and Methods: 10 human teeth, from which the roots had been removed, were embedded in epoxy resin, and their surfaces were smoothed. The specimens were divided into two groups; in group 1, a whitening solution without calcium was used, while in group 2, the solution included calcium. Each specimen was evaluated at 6 different points before the bleaching treatment, and these points were reassessed after each session. A total of five sessions were carried out. Concentrations of calcium and phosphorus were measured by using the technique of X-ray fluorescence., Results: After performing a statistical analysis, it was found that there was no statistically significant loss of calcium and phosphorus during the whitening treatment, and the groups showed no statistical differences., Conclusion: Excessive use of hydrogen peroxide, with or without calcium, causes no loss of calcium and phosphorus.

Introduction: Wipple disease (WD) is a rare chronic disease caused by the bacillus Tropheryma whipplei . Constitutive, rheumatologic, gastrointestinal, cardiac, cerebral, lymphatic, cutaneous, and ophthalmological signs are possible systemic symptoms. However, thrombotic manifestations are rarely described as "stroke-like syndrome" or arterial thrombosis. Diagnosis is based on clinical manifestations and pathological examination. Laboratory findings may include anemia, leukocytosis, and thrombocytosis., Objective: We report a case of venous thrombosis as initial manifestation of WD., Case Report: We describe the case of a 53-year-old male with iliofemoral vein thrombosis followed by intermittent diarrhea, loss of appetite, abdominal distension, and bloating. A mild malnutrition state with a weight loss of 13 kg, pallor (+/4 +), presence of lower-limb edema (+/4 +), and hypertympanic distended abdomen occurred. Laboratory tests on admission revealed anemia, positive inflammatory activity tests, and normal coagulation. Endoscopic examination showed villous edema with white dotted infiltrates in the second duodenal portion and intestinal lymphangiectasia in the terminal ileum. Pathological examination revealed numerous macrophages with positive periodic acid-Schiff inclusions. Venous Doppler ultrasound showed extensive deep thrombosis on the left lower limb and recanalization of the femoral vein in the right lower limb. The patient was treated with ceftriaxone and enoxaparin sodium, which led to an improvement of gastrointestinal and thrombosis symptoms., Comments: Hypercoagulability, endothelial damage, vasculitis, and blood stasis are present in T. whipplei infection, which are associated with the activation of inflammatory mechanisms as well as procoagulant and thromboembolic events. WD should be part of the differential diagnosis of diseases that cause venous thrombosis of unknown origin.

The present study evaluated the influence of the cement film thickness on the push-out bond strength of glass fiber posts in the cervical, medium, and apical thirds of root canal spaces. Thirty roots were randomly divided into three groups, according to the fiber post system's drills: (G1) #2; (G2) #3; (G3) #4. The posts were cemented using a self-adhesive cement, and a small amount of powdered Rhodamine B was used as a stain. Images of both sides of each slice were obtained before and after the push-out test. To determine the cement thickness, a macro routine was developed using the software KS 400. The data were analyzed statistically using Kruskal-Wallis and Dunn's test. G2 (14.62 ± 5.15 MPa) showed statistically higher bond strength values than G1 (10.04 ± 5.13 MPa) and G3 (7.68 ± 6.14 MPa). All groups presented higher bond strength values in the apical third. The bur diameter significantly influenced the results of the shear bond strength for the push-out test. The slight increase in the cement thickness allowed an increase in the values of shear bond strength when compared to very thin or very thick cement films.

Statement of the Problem: Fixed prosthesis and partial dental prosthesis frameworks are usually made from welded Ni-Cr-based alloys. These structures can corrode in saliva and have to be investigated to establish their safety., Purpose: The purpose of this study was to evaluate the corrosion behavior of joints joined by tungsten inert gas (TIG) welding and conventional brazing in specimens made of commercial Ni-Cr alloy in Fusayama artificial saliva at 37°C (pH 2.5 and 5.5)., Material and Methods: Eighteen Ni-Cr base metal specimens were cast and welded by brazing or tungsten inert gas methods. The specimens were divided into 3 groups (base metal, 2 welded specimens), and the composition and microstructure were qualitatively evaluated. The results of potential corrosion and corrosion current density were analyzed with a 1-way analysis of variance and the Tukey test for pairwise comparisons (α=.05)., Results: Base metal and tungsten inert gas welded material showed equivalent results in electrochemical corrosion tests, while the air-torched specimens exhibited low corrosion resistance. The performance was worst at pH 2.5., Conclusions: These results suggest that tungsten inert gas is a suitable welding process for use in dentistry, because the final microstructure does not reduce the corrosion resistance in artificial saliva at 37°C, even in a corrosion-testing medium that facilitates galvanic corrosion processes. Moreover, the corrosion current density of brazed Ni-Cr alloy joints was significantly higher (P<.001) than the base metal and tungsten inert gas welded joints., (Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Introduction: The shear bond strength of orthodontic brackets bonded to micro-hybrid and micro-particulate resins under different surface treatment methods was assessed., Methods: Two hundred and eighty test samples were divided into 28 groups (n = 10), where 140 specimens were filled with Durafill micro-particulate resin and 140 with Charisma composite. In 140 samples, a coupling agent (silane) was applied. The surface treatment methods were: Phosphoric and hydrofluoric acid etching, sodium bicarbonate and aluminum oxide blasting, stone and burs. A Universal Instron Machine was used to apply an occlusal shear force directly to the resin composite bracket surface at a speed of 0.5 mm/min. The means were compared using analysis of variance and multivariate regression to assess the interaction between composites and surface treatment methods., Results: Means and standard deviations for the groups were: Sodium bicarbonate jet 11.27 ± 2.78; burs 9.26 ± 3.01; stone 7.95 ± 3.67; aluminum oxide blasting 7.04 ± 3.21; phosphoric acid 5.82 ± 1.90; hydrofluoric acid 4.54 ± 2.87, and without treatment 2.75 ± 1.49. An increase of 1.94 MPa in shear bond strength was seen in Charisma groups. Silane agent application reduced the Charisma shear bond strength by 0.68 Mpa, but increased Durafill means for bicarbonate blasting (0.83), burs (0.98) and stone drilling (0.46)., Conclusions: The sodium bicarbonate blasting, burs and stone drilling methods produced adequate shear bond strength and may be suitable for clinical use. The Charisma micro hybrid resin composite showed higher shear bond means than Durafill micro particle composite.

At this time, restoration of noncarious cervical lesions (NCCLs) is a common occurrence in clinics nowadays. Some reasons for this are the growth of the elderly population, a smaller rate of tooth loss, and possibly the increase of some etiologic factors. These factors include inadequate brushing techniques in gingival recession cases, corrosive food and drink consumption, and occlusal stress concentrating factors (occlusal interferences, premature contacts, habits of bruxism, and clenching). Unfortunately, Class V restorations also represent one of the less durable types of restorations and have a high index of loss of retention, marginal excess, and secondary caries. Some causes for these problems include difficulties in isolation, insertion, contouring, and finishing and polishing procedures. This work aims to help dentists in choosing the best treatment strategy, which necessarily involves steps of problem identification, diagnosis, etiological factor removal or treatment, and, if necessary, restoration. Finally, appropriate restorative techniques are suggested for each situation.

Dentinal surfaces prepared with air abrasion have considerably different characteristics from those prepared with conventional instruments. Different hybrid layer morphology and thickness occur, which can result in differences in the quality of restorations placed on dentinal surfaces prepared with a diamond bur compared to surfaces prepared using air abrasion. The objective of this study was to compare the hybrid layer thickness and morphology formed utilizing Scotchbond Multi-Purpose Plus (SBMP) on dentin prepared with a diamond bur in a high-speed handpiece and on dentin prepared using air abrasion. Flat dentin surfaces obtained from five human teeth were prepared using each method, then treated with the dentin adhesive system according to manufacturer's instructions. After a layer of composite was applied, specimens were sectioned, flattened, polished, and prepared for scanning electron microscopy. Ten different measurements of hybrid layer thickness were obtained along the bonded surface in each specimen. SBMP produced a 3.43 ± 0.75 µm hybrid layer in dentin prepared with diamond bur. This hybrid layer was regular and found consistently. In the air abrasion group, SBMP produced a 4.94 ± 1.28 µm hybrid layer, which was regular and found consistently. Statistical ANOVA (P = 0.05) indicated that there was a statistically significant difference between the groups. These data indicate that the air abrasion, within the parameters used in this study, provides a thick hybrid layer formation.

The main goal of the current study was to evaluate the surface roughness of tooth-colored restorative materials after different finishing/polishing protocols, including a liquid polisher (BisCover, BISCO, Schaumburg, IL, USA). The restorative materials tested included two nanofilled resin composites (Filtek Supreme, 3M Dental Products, St Paul, MN, USA and Grandio, Voco, Cuxhaven, Germany), one resin-modified glass ionomer cement (Vitremer, 3M Dental Products) and one conventional glass ionomer cement (Meron Molar ART, Voco). The finishing/polishing methods were divided into five groups: G1 (compression with Mylar matrix), G2 (finishing with diamond burs), G3 (Sof-Lex, 3M Dental Products), G4 (BisCover, BISCO, after diamond burs) and G5 (BisCover after Sof-Lex). Five cylindrical specimens of each material were prepared for each group according to the manufacturer's instructions. The finishing/polishing methods were performed by a single operator in one direction to avoid variations at low speed (15,000 RPM). The surface roughness was evaluated using a 3-D scanning instrument with two parameters considered (Ra and Rz). The data was analyzed using one-way ANOVA followed by a multiple comparison Tukey's test. The results showed that BisCover (BISCO) was capable of reducing surface roughness and provided polished surfaces for all materials, enhancing smoothness over already polished surfaces (Sof-Lex, 3M Dental Products) and achieving polishing after finishing with diamond burs.

Dentinal surfaces prepared with Er:YAG laser have significantly different characteristics from those prepared with conventional instruments. Different hybrid layer morphologies and thicknesses occur, which may result in differences in the quality of restorations placed on dentinal surfaces prepared with a diamond bur when compared with using an Er:YAG Laser. This study compared the hybrid layer thickness and morphology formed utilizing Scotchbond Multipurpose Plus (SBMP) on dentin prepared with a diamond bur in a high speed handpiece and dentin prepared with an Er:YAG laser. Flat dentin surfaces obtained from five human teeth were treated with the two methods and then with the dentin adhesive system according to the manufacturer's instructions. After a layer of composite was applied, the specimens were sectioned, flattened, polished and prepared for SEM observation. Ten different measurements of hybrid layer thickness were obtained along the bonded surface in each specimen. Results showed that SBMP produced a 3.43 +/- 0.75 microm hybrid layer in dentin prepared with a diamond bur. This hybrid layer was regular and constantly found. In the laser group, the dentin adhesive system produced a 1.54 +/- 0.35 microm hybrid layer that was very irregular and not found constantly. Statistical analysis of variance (p < 0.05) showed that there was a statistically significant difference between the groups. These data indicate that the Er:YAG laser, with parameters used in the experiment, is not a preparation method that allows for a thick hybrid layer formation, which is in opposition to using a diamond bur in a high speed turbine.

The purpose of this study was to compare the effect of a self-etching primer and a non-rinse conditioner with the effect of a conventional adhesive system on the penetration depth in dentin of human teeth, using scanning electronic microscopy (SEM). Fifteen human third molar teeth were sectioned into 2 pieces. All pieces were flattened with grade 600 to 1200 silicon carbide paper and divided into 6 groups: group 1 - Prime & Bond NT (NT), negative control; group 2 - 37% phosphoric acid + Prime & Bond NT (PANT), positive control; group 3 - Non-rinse Conditioner (NRC) + Prime & Bond NT (NRCNT); group 4 - NRC + Prime & Bond 2.1 (NRCPB); group 5 - NRC + Scotchbond MP (NRCSB); group 6 - Prompt L-Pop (PLP). All teeth were covered with Dyract AP. The tooth fragments were decalcified, and its resin replicas were evaluated by SEM by three previously standardized examiners. The penetration was scored from 0 (no penetration) to 3 (maximum penetration). The Kruskal-Wallis and Mann-Whitney U tests (p<0.05) showed three statistically homogeneous groups: (NT, NRCPB, NRCSB and PLP), (NRCNT) and [PANT]. The authors concluded that the self-etching primer and the non-rinse conditioner provide a lower penetration depth in human tooth dentin than the conventional adhesive system.

This study evaluated the "in vitro" shear bond strength of two materials to bovine enamel when used as porcelain laminate veneer bonding systems. The authors used the dual-cured resin cement Variolink II (Vivadent) and the light-cured flowable composite Natural-Flow (DFL). Porcelain cylinders were bonded to bovine enamel following manufacturers' directions. After 24 hours of storage in distilled water and thermocycling, the specimens were tested on a universal testing machine to determine the shear bond strengths. Mean strengths found in Groups 1 (resin cement) and 2 (flowable composite) were not statistically different (p < or = 0.05). The authors concluded that the shear bond strength of Natural-Flow is not different from Variolink II and that flowable composites can be a suitable alternative when used as porcelain laminate veneer bonding systems.