Objectives: To assess the performance of a novel resin-modified glass-ionomer cement (pRMGIC) bonded to various tooth tissues after two-time intervals. Methods: 192 sound human molars were randomly assigned to 3 groups (n = 64): sound enamel, demineralised enamel, sound dentine. Sixty-four teeth with natural carious lesions including caries-affected dentine (CAD) were selected. All substrates were prepared, conditioned and restored with pRMGIC (30% ethylene glycol methacrylate phosphate (EGMP, experimental), Fuji II LC (control), Fuji IX, and Filtek™ Supreme with Scotchbond ™ Universal Adhesive. Shear bond strength (SBS) was determined after 24 h and three months storage in SBF at 37C. The debonded surfaces were examined using stereomicroscopy and scanning electron microscopy (SEM). Multivariate Analysis of Variance (MANOVA), Bonferroni post hoc tests (alpha=0.05) and independent T-tests were used for multifactorial data analysis. Results: The hydrophilicity and functionality of EGMP enhanced the bond strength of the pRMGIC to different substrates after 24 h and 3 months as compared to F2LC (p<0.05). Adhesive failures were found to decrease with pRMGIC and integration into exposed enamel prisms and dentine tubules was observed with SEM. Ageing enhanced bond strength of pRMGIC to all substrates but was statistically significantly only in sound dentine. The SBS of pRMGIC was higher with sound vs. demineralised enamel at both time periods (p<0.001), while it was higher to CAD initially and to sound dentine post-storage (p = 0.004). Conclusions: pRMGIC exhibited enhanced bonding performance to various tooth tissues with an ability to seal exposed enamel prisms and dentine tubules. Clinical significance: pRMGIC is a promising material exhibiting long-lasting bonded-tooth interfaces, for its use in minimally invasive reparative techniques
Oilwell cementing operations are crucial for drilling and completion, preserving the well's productive life. However, weak and permeable formations pose a high risk of cement slurry loss, leading to failure. Lightweight cement, like foamed cement, is used to avoid these difficulties. This study is focused on creating a range of foamed slurry densities and examining the effect of gas concentration on their rheological properties. The foaming agent and foam stabilizer are tested, and the optimal concentration is determined to be 2% and 0.12%, respectively, by the weight of the cement.
Furthermore, the construction of samples of foam cement with different densities (0.8, 1.0, 1.2, 1.4, and 1.6) g/cc is performed to f
... Show MoreThe work concerned with studying the effect of (SiO2) addition as a
filler on the adhesive properties of (PVA). Samples were prepared as
sheets by using casting method. The mechanical properties showed
that increase in tensile strength from (34MPa) to (68MPa) when
(SiO2) added to (PVA). The adhesive strength showed that joint
properties depend upon specific adhesive characteristic of material
(PVA) and (SiO2\PVA)composites at different concentrations (1.5%,
2.5%, 3.5%, 4.5wt%), the cohesive strength of the adhesive material,
the joint design, and adherent type (Sponge Rubber(SR), Natural
leather (NL), Vulcanized Rubber(VR), and Cartoon). The results
proved the tensile strength increased with (SiO2) ratio, so
This study “discusses the benefit of “addition waste paper as a “new cellulose material “in mortar mixes. A partial addition of waste paper by cement weight was achieved to produce cement composite mortar. Pulp and paper is the third major industrial dumper of air, soil and water. In recent year, paper and paperboard constitute a greater portion of many countries’ urban solid discarded generation. Beside, it increases characteristic “strength due to existence “of hydrogen links “in the microstructure of “paper. Furthermore, it consume “better thermal protection. The addition percentages “of waste paper used “in this work were (5%, 10%, 15% and 20%) by “mass of cement to measure and evaluat
... Show MoreBackground: Vitamin D improves innate immunity by enhancing the expression of antimicrobial peptides. The antimicrobial action of cathelicidin is widespread and effective against cariogenic bacteria. This research aimed to investigate the effect of vitamin D deficiency on the level of salivary cathelicidin concerning dental caries experience.
Subjects and Methods: A case-control study was carried out, and the sample was composed of 80 females; the study group involved 40 females with a serum vitamin D concentration of less than 10 ng/ml. In addition to the control group involving 40 females wh
... Show MoreBackground: Dental caries is the most common oral problem, although dental caries is not life threating, it has aharmful effect on quality of life. Socioeconomic factors were found to be strong predictors of the prevalence of oral diseases in children, likes family income, occupational prestige, and education. The aim of this study is to assess the effect of socioeconomic factors on occurrence dental caries in their children. Materials and methods: The sample consists of 550 kindergartens children aged between (4-5) years were selected randomly, girls and boys. The kindergartens selection was randomly from different geographical areas in Al-Najaf governorate. Information was taken from children's parents using questionnaire with the help o
... Show MoreIn this study, titanium dioxide (TiO2) nanoparticles incorporated with cement were synthesis by a simple casting method as a function concentration of TiO2 (0.2, 0.4, 0.8, 1, and 2 wt%). The prepared samples were characterized using the technique of Field Emission Scanning Electron Microscope (FESEM) and UV-Visible spectrophotometer, which was used to measure the adsorption spectra. The observed photocatalytic efficiency of TiO2 nanoparticles (NP) incorporated with cement was investigated by decomposing the dye methyl blue (MB) solution under sunlight irradiation. According to the slope, the value of the k constant at the best sample is 0.8wt%, k=0.8265 min-1. FESEM image of the TiO2
... Show MoreAmong more than 200 different human papilloma viral genotypes, the association of low oncogenic risk-HPV genotypes have been recognized with a variety of oral, oropharyngeal, nasopharyngeal benign tumors as well as non-neoplastic polyposis and papillomas and adenoid hypertrophy. This prospective case- control study aims to determine the rate of DNA detection of HPV genotype 6/11 in nasopharyngeal adeno- tonsillar tissues from a group of patients subjected to adenoctomy for adenoid hypertrophy . A total number of nasopharyngeal adeno-tonsillar tissue specimens from pediatric patients with adenoid hypertrophy were enrolled; 40 nasopharyngeal adeno-tonsillar tissues from patients with adenoid hypertrophy, and 20 normal nasal tissue specimen
... Show MoreBackground: the aim of this study was to evaluate the effect of different surface acids treatments (37%phospjoric acid, 5%hydrofluoric acid, 1.23 acidulated phosphate fluoride) of feldspathic ceramic VITA 3D MASTER , and the effect of thermocycling on shear bond strength using a ceramic repair kit (ivoclar/vivadent). Material and Methods: sixty Nickel-Chromium metal base plates were prepared(9mm diameter,3mm depth) using lost wax technique, 2mm thick layer of ceramic(VITA 3D MASTER) fused to metal plates, all specimens were embedded in acrylic resin blocks except their examined surfaces and divided into 3 main groups 20 specimens each, Grp A: treatment with 37%phosphoric acid for 2 mins, Grp B: etching with 5% hydrofluoric acid for 2mins,
... Show MoreIn the present work, the critical micelle concentration (CMC) of the solution of Sodium dodecyl sulfate (SDS) as anionic surfactant, Cocamidopropyl Betaine (CAPB) as amphoteric surfactant, and their mixture have been determined using surface tension and conductivity measurements at a temperature range 293 -323 K. The adsorption and thermodynamic micellization parameters (?G?m, ?G?ads, ?max ,Amin,?cmc ) for individual surfactants was calculated. Rosen model which is focuses on the adsorbed mixed surfactant film at the air/solution interface was used to calculate the interaction parameter ( ?? ) at the interface and the activity coefficients g1 and g2. The results indicate that the CMC of the individual surfactants was affected by
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