Effects of ethylenediaminetetraacetic acid and sodium hypochlorite on the bond strength of bonding agents to pulp chamber lateral walls

AbstractBackground/purposeThe purposes of this in vitro study were to determine the microtensile bond strengths of four different dentin adhesive materials placed in pulp chamber walls, and to test the effects of 5% sodium hypochlorite (NaOCl) and 17% ethylenediaminetetraacetic acid (EDTA) pretreatments on resin dentin bond strengths.Materials and methodsRecently extracted human third molars were selected. The teeth were divided into four groups. Specimens in each group were treated as follows: irrigated with distilled water; irrigated with EDTA for 5 minutes; irrigated with sodium hypochlorite for 5 minutes; and irrigated with EDTA for 5 minutes followed by NaOCl for 5 minutes. Treated specimens were dried, bonded with a total-etching adhesive, two self-etching adhesives, or a one-bottle self-etching adhesive system. After the bonding procedure and composite restoration, teeth were sectioned, and 15 dentin sticks were obtained. Microtensile testing was performed, and scanning electron micrographs were taken of each irrigated group.ResultsIn the control group, the one-bottle self-etching adhesive system showed statistically higher bond strength values. EDTA irrigation did not affect the bond strength except for the total-etching adhesive. NaOCl significantly reduced the bond strengths of all adhesives. The EDTA and NaOCl combination did not show a statistically significant reduction in bond strengths of the adhesives to pulpal dentin.ConclusionThere was a reduction in bond strengths of all adhesive systems used to test pulp chamber lateral walls after endodontic irrigation solutions were used

El ve Döner Alet Kullanımı Sonrasında Apikalden Taşan Debris Miktarının ve Kalsiyum Hidroksit Uzaklaştırılmasının Değerlendirilmesi

Amaç: Bu çalışmanın amacı el ve döner alet kullanımından sonra kök kanal duvarlarında kalan kalsiyum hidroksit miktarının ve kalsiyum hidroksit uzaklaştırılması süresince apikalden taşan debris miktarının değerlendirilmesidir.Gereç ve Yöntem: Yirmi-dört çekilmiş üst çene kesici diş K-tipi eğeler ile prepare edildi ve kalsiyum hidroksit ile dolduruldu. Dört diş pozitif ve negatif kontrol olarak ayrıldı. Kalan dişler iki gruba ayrıldı: ana apikal eğe grubu ve ProTaper Universal döner alet grubu. Uzaklaştırma işlemleri boyunca yıkama solüsyonu olarak sitrik asit kullanıldı. Apikalden taşan debris toplandı ve gruplar arasında karşılaştırıldı. Daha sonra dişler dikey eksenleri boyunca ikiye ayrıldı, stereomikroskop kullanılarak fotoğrafları çekildi ve bilgisayar programı kullanılarak resimlerin analizi yapıldı. Veriler tek yönlü varyans analizi ile istatistiksel olarak analiz edildi.Bulgular: Her iki grupta kalsiyum hidroksit uzaklaştırma süresince ölçülebilir miktarda apikalden taşan debris gözlemlendi. İstatiksel analiz apikal olarak debris çıkışı ve uzaklaştırılan kalsiyum hidroksit bakımından teknikler arasında anlamlı farkın olmadığını gösterdi.Sonuçlar: Kalsiyum hidroksit uzaklaştırma süresince tekniğe bağlı olmaksızın apikal olarak debris çıkışı meydana gelmektedir. Kullanılan tekniklerden hiçbirisi kök kanal duvarlarından kalsiyum hidroksiti tamamen uzaklaştıramadı

Bonding of different self-adhesive resins to high-strength composite resin block treated with surface conditioning

Purpose: This study aimed to evaluate the effects of chemical conditioning and self-adhesive resins (SARs)on the bonding of mechanically conditioned high-strength composite resin block (HSCRB). Methods: Eighteen sections of HSCRB (KZR-CAD HR 3 Gammatheta, Yamakin) were treated with alumina air abrasion and randomly divided into 3 groups according to the SARs for bonding: RelyX Unicem 2 (RXU), SA Luting Plus (SAL), and G-Cem ONE (GCO). The sections were further divided into 3 subgroups according to the chemical conditioning of the adherend surfaces: no conditioning (C), universal adhesive (UA), and a mixture of γ-MPTS and 10-MDP (MM). After the surface conditioning, the sections were cemented with the SARs. Each cemented section was cut into 40 beams. Half of the beams were thermocycled (4 °C/60 °C, 10,000 cycles). The micro-tensile bond strength (μTBS) values were measured using a universal testing machine.Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), contact angles, and surface roughness measurements were performed on the adherend surfaces of each subgroup.Results: RXU showed the highest μTBS values among the 3 SARs tested, while MM application exhibited the highest μTBS values among the 3 chemical conditioning methods tested. After thermocycling, the samples in the RXU/MM, RXU/UA, and GCO/MM groups showed no significant changes in the μTBS values,whereas the others showed a significant reduction. Conclusions: The bond strength of HSCRB was influenced by the chemical conditioning, SARs, and aging. γ-MPTS and 10-MDP application yielded higher μTBS values of mechanically treated HSCRB than the UA

Six-month color change and water sorption of 9 new-generation flowable composites in 6 staining solutions

Abstract Color match and water sorption are two factors that affect restorative materials. Discoloration is essential in the lifespan of restorations. The aim of this study was to evaluate color change and water sorption of nine flowable composites at multiple time points over 6 months. 60 samples of each composite were divided into two groups (Color Change and Water Sorption/Solubility). Each Color Change group was divided into six subgroups, which were immersed in distilled water (DW), coffee (CF), Coca-Cola (CC), red wine (RW), tea (TE) and orange juice (OJ). The color was measured at the baseline, 1, 2, 3 and 4 weeks, and 3 and 6 months and color change values (ΔE) were calculated. Each Water Sorption [WS]/Solubility [WL] group was tested according to ISO 4049:2009. The data were evaluated using two-way ANOVA, Fisher’s post-hoc test and Pearson’s correlation test. The composite with the lowest ΔE differed for each solution: Filtek™ Bulk Fill in DW (∆E = 0.73 (0.17–1.759)); Vertise Flow in CF (∆E = 14.75 (7.91–27.41)), in TE (∆E = 7.27 (2.81–24.81)) and OJ (∆E = 3.17 (0.87–9.92)); Tetric EvoFlow® in CC (∆E = 1.27 (0.45–4.02)); and Filtek™ Supreme XTE in RW (∆E = 8.88 (5.23–19.59)). RW caused the most discoloration (∆E = 23.62 (4.93–51.36)). Vertise Flow showed the highest water sorption (WS = 69.10 ± 7.19). The Pearson test showed statistically significant positive correlations between water sorption and solubility and between water sorption and ∆E; the positive solubility-∆E correlation was not statistically significant. The findings suggest that water sorption is one factor associated with the ability of composites to discolor; however, discoloration is a multifactorial problem

Effects of nesfatin-1 on atrial contractility and thoracic aorta reactivity in male rats

Background: This study aimed to examine the effects of nesfatin-1 on thoracic aorta vasoreactivity and to investigate the inotropic and chronotropic effects of nesfatin-1 on the spontaneous contractions of the isolated rat atria. Methods: Isolated right atria and thoracic aorta were used in organ baths. The reactivity of the thoracic aorta was evaluated by potassium chloride (KCl), phenylephrine (Phe), acetylcholine (ACh), and sodium nitroprusside (SNP). The effects of nesfatin-1 on the spontaneous contractions of the rat atria were also examined. Results: Nesfatin-1 (0.1–100 ng/ml) produced a concentration-dependent relaxation response in rat thoracic aorta. The relaxant responses to nesfatin-1 were inhibited by the removal of endothelium, NO synthase blocker N-nitro-L-arginine methyl ester (L-NAME, 10−4 M), and soluble guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, 10–5 M). Nesfatin-1 (10 ng/ml, 30 min) increased the relaxation responses to either ACh or SNP, and the contractile response to both Phe and KCl did not significantly change in the arteries that were incubated with nesfatin-1 compared with the controls. The thoracic aorta contractions induced by the stepwise addition of Ca2+ to a high KCl solution with no Ca2+ were not significantly changed by nesfatin-1. Under calcium-free conditions, the contractions of the thoracic aorta rings incubated with nesfatin-1 in response to Phe were not significantly lower than those of the rings from the control rats. Nesfatin-1 showed positive inotropic and chronotropic effects on rat atria. Conclusion: Nesfatin-1 significantly changed the vascular responsiveness in rat thoracic aorta and produced positive inotropic and chronotropic effects on rat atria

Assessing staining resistance of a CAD/CAM interpenetrating network composite material

Abstract Background Color change of dental materials over time because of staining agents has important effects on the long-term prognosis of dental esthetic treatments. In the present study, staining resistance of an interpenetrating network composite material with different translucency levels (translucent and high translucent) and various surface procedures for finishing were investigated. Methods Same shade CAD/CAM interpenetrating network composite specimens having two different translucency levels were prepared using by a water cooling cutting saw. Specimens were grouped and different finishing procedures were performed. Then, specimens were kept in distilled water, red wine and coffee for different periods. Color was evaluated before and after exposure to staining liquids using a clinical spectrophotometer. Results In the 7 days Glaze group (ΔE00 > 2.2), color difference was only perceivable in the specimens kept in red wine. In the 28 days red wine high translucent groups, only the high translucent Clinical group showed a clinically acceptable (ΔE00  2.2). In the 28 day measurements, all the translucent groups showed a clinically perceivable color change (ΔE00 > 2.2). Of the translucent groups kept in coffee for 28 days, it was observed that only the translucent Clinical group demonstrated a clinically non-perceivable color change (ΔE00 < 2.2). Conclusions All the translucent groups kept in red wine showed a clinically perceivable color change after 28 days. Only the high translucent Clinical Kit group showed a clinically acceptable color change. Among high translucent and translucent specimens kept in coffee only the translucent Clinical group showed a clinically acceptable color change after 28 days

Color recovery effect of different bleaching systems on a discolored composite resin

Background and Purpose: Discoloration of resin‑based composites is a commonly encountered problem, and bleaching agents may be used for the therapy of the existing discoloration. The purpose of this study was to investigate in vitro color recovery effect of different bleaching systems on the heavily discolored compositeresin. Materials and Methods: Fifty disk‑shaped dental composite specimens were prepared using A2 shade nanohybrid universal composite resin (3M ESPE Filtek Z550, St. Paul, MN, USA). Composite samples were immersed in coffee and turnip juice for 1 week in each. One laser activated bleaching (LB) (Biolase Laserwhite*20) and three conventional bleaching systems (Ultradent Opalescence Boost 40% (OB), Ultradent Opalescence PF 15% home bleaching (HB), Crest 3D White [Whitening Mouthwash]) were tested in this study. Distilled water was used as control group. The color of the samples were measured using a  spectrophotometer (VITA Easy shade Compact, VITA Zahnfabrik, Bad Säckingen, Germany). Color changes (ΔE00) were calculated using the CIEDE2000 formula. Statistical analyses were conducted using paired samples test, one‑way analysis of variance, and Tukey’s multiple comparison tests (α = 0.05).Results: The staining beverages caused perceptible discoloration (ΔE00 &gt; 2.25). The color recovery effect of all bleaching systems was statistically determined to be more effective than the control group (P &lt; 0.05). Although OB group was found as the most effective bleaching system, there was no statistically significant difference among HB, OB, and LB groups (P &gt; 0.05).Conclusion: Within the limitation of this in vitro study, the highest recovery effect was determined in office bleaching system among all bleaching systems. However, home and laser bleaching systems were determined as effective as office bleaching system.Keywords: Composite resin, discoloration, home bleaching, laser activated  bleaching, office bleaching, whitening mouthwash

Effects of erbium‑and chromium‑doped yttrium scandium gallium garnet and diode lasers on the surfaces of restorative dental materials: A scanning electron microscope study

Aim: The aim of this study is to evaluate the potential effects of laser irradiation, which is commonly performed in periodontal surgery, on the surfaces of restorative materials.Materials and Methods: Five different restorative dental materials were used in this study, as follows: (1) Resin composite, (2) polyacid‑modified resin composite (compomer), (3) conventional glass ionomer cement (GIC), (4) resin‑modified glass ionomer cement (RMGIC), and (5) amalgam. Four cylindrical samples (8 mm diameter, 2 mm height) were prepared for each restorative material. In addition, four freshly extracted, sound human incisors teeth were selected. Two different laser systems commonly used in periodontal surgery were examined in this study: A 810 nm diode laser at a setting of 1 W with continuous‑phase laser irradiation for 10 s, and an erbium‑and chromium‑doped yttrium scandium gallium garnet (Er, Cr: YSGG) laser at settings of 2.5 W, 3.25 W, and 4 W with 25 Hz laser irradiation for 10 s. Scanning electron microscopy (SEM) analysis was performed to evaluate the morphology and surface deformation of the restorative materials and tooth surfaces.Results: According to the SEM images, the Er, Cr: YSGG laser causes irradiation markings that appear as demineralized surfaces on tooth samples. The Er, Cr: YSGG laser also caused deep defects on composite, compomer, and RMGIC surfaces because of its high power, and the ablation was deeper for these samples. High‑magnification SEM images of GIC samples showed the melting and combustion effects of the Er, Cr: YSGG laser, which increased as the laser power was increased. In amalgam samples, neither laser left significant harmful effects at the lowest power setting. The diode laser did cause irradiation markings, but they were insignificant compared with those left by the Er, Cr: YSGG laser on the surfaces of the different materials and teeth.Conclusion: Within the limitations of this study, it can be concluded that Er, Cr: YSGG laser irradiation could cause distortions of the surfaces of restorative materials. Diode lasers can be preferred for periodontal surgery.Key words: Erbium chromium‑doped yttrium scandium gallium garnet, diode laser, restorative dental materials, scanning electron microscop

Assessment the Bond Strength of Ceramic Brackets to CAD/CAM Nanoceramic Composite and Interpenetrating Network Composite after Different Surface Treatments

Adult orthodontics may confront problems related to the bonding performance of orthodontic brackets to new generation restorative materials used for crown or laminate restorations. The aim of the present study was to investigate the shear bond strength of ceramic brackets to two new generation CAD/CAM interpenetrating network composite and nanoceramic composite after different surface treatments. Er,Cr:YSGG Laser, hydrofluoric acid (9%), sandblasting (50 μm Al2O3), and silane were applied to the surfaces of 120 CAD/CAM specimens with 2 mm thickness and then ceramic brackets were bonded to the treated surfaces of the specimens. Bond strength was evaluated using the shear bond strength test. According to the results, CAD/CAM block types and surface treatment methods have significant effects on shear bond strength. The lowest bond strength values were found in the specimens treated with silane (3.35 ± 2.09 MPa) and highest values were found in the specimens treated with sandblast (8.92 ± 2.77 MPa). Sandblasting and hydrofluoric acid surface treatment led to the most durable bonds for the two types of CAD/CAM blocks in the present study. In conclusion, different surface treatments affect the shear bond strength of ceramic brackets to CAD/CAM interpenetrating network composite and nanoceramic composite. Among the evaluated treatments, sandblasting and hydrofluoric acid application resulted in sufficient bonding strength to ceramic brackets for both of the CAD/CAM materials