Materials and Methods: Ninety aluminum oxide ceramic (Turkom-Ceramic Sdn. Bhd., Kuala Lumpur, Malaysia) specimens were produced and divided into nine groups to receive the following surface treatments: control group, no treatment (Group C), sandblasting (Group B), silica coating (Group S), erbium: yttrium-aluminum-garnet (Er:YAG) laser irradiation at 150 mJ 10 Hz (Group L1), Er:YAG laser irradiation at 300 mJ 10 Hz (Group L2), sandblasting + L1 (Group BL1), sandblasting + L2 (Group BL2), silica coating + L1 (Group SL1), and silica coating + L2 (Group SL2). After surface treatments, surface roughness (SR) values were measured and surface topography was evaluated. Resin cement was applied on the specimen surface, and shear bond strength (SBS) tests were performed. Data were statistically analyzed using one-way ANOVA and Tukey's multiple comparisons at a significance level of P < 0.05.
Results: Group S, SL1, and SL2 showed significantly increased SR values compared to the control group (P < 0.05); therefore, no significant differences were found among the SR values of Groups B, BL1, BL2, L1, and L2 and the control group (P > 0.05). Group S showed the highest SBS values, whereas the control group showed the lowest SBS values.
Conclusion: Silica coating is the most effective method for resin bonding of high strength ceramic, but Er:YAG laser application decreased the effectiveness.
Purpose of study: The study aimed to mask and evaluate the unpleasant bitter taste of azithro-mycin (AZ) in the dry suspension dosage form by physisorption technique.
Materials and methods: AZ was selected as an adsorbent and titanium dioxide nanoparticles as adsorbate. The AZ nanohybrids (AZN) were prepared by treating fixed amount of adsorbent with a varied amount of adsorbate, prepared separately by dispersing it in an aqueous medium. The mixture was sonicated, stirred followed by filtration and drying. The AZN produced were characterized by various techniques including scanning electron microscopy (SEM), energy dispersive X-rays (EDX), powder X-ray diffraction (PXRD), HPLC and Fourier-transformed infrared (FTIR). The optimized nanohybrid was blended with other excipients to get stable and taste masked dry suspension dosage form.
Results: The results confirmed the adsorption of titanium dioxide nanoparticles on the surface of AZ. The fabricated optimized formulation was subjected for taste masking by panel testing and accelerated stability studies. The results showed a remarkable improvement in bitter taste masking, inhibiting throat bite without affecting the dissolution rate. The product showed an excellent stability both in dry and reconstituted suspension. The optimized formulation of AZN and was found stable when subjected to physical and chemical stability studies, this is because of short and single step process which interns limits the exposure of the product to various environmental factors that could potentially affect the stability of the product. The dissolution rate of the optimized formulation of AZN was compared with its marketed counterpart, showing the same dissolution rate compared to its marketed formulation.
Conclusion: The current study concludes that, by fabricating AZ-titanium nanohybrids using physisorption can effectively mask the bitter taste of the drug. The palatability and stability of azithromycin formulation was potentially enhanced without affecting its dissolution rate.
MATERIALS AND METHODS: An experimental adhesive system based on bis-GMA, HEMA and hydrophobic monomer was doped with RF0.125 (RF - Riboflavin) or RF/VE-TPGS (0.25/0.50) and submitted to μTBS evaluation. Resin dentine slabs were prepared and examined using SEM and TEM. Adhesion force was analysed on ends of AFM cantilevers deflection. Quenched peptide assays were performed using fluorescence scanner and wavelengths set to 320nm and 405nm. Cytotoxicity was assessed using human peripheral blood mononuclear cell line. Molecular docking studies were carried out using Schrödinger small-molecule drug discovery suite 2018-2. Data from viable cell results was analyzed using one-way ANOVA. Bond strength values were analysed by two-way ANOVA. Nonparametric results were analyzed using a Kruskal-Wallis test at a 0.05 significance level.
RESULTS: RF/VE-TPGS0.25 groups showed highest bond strength results after 24-h storage in artificial saliva (p<0.05). RF/VE-TPGS0.50 groups showed increased bond strength after 12-months of ageing. RF/VE-TPGS modified adhesives showed appreciable presence of a hybrid layer. Packing fraction indicated solid angle profiles describing well sized density and topology relations for the RF/VE-TPGS adhesives, in particular with the RF/VE-TPGS0.50 specimens. Qualitative analysis of the phenotype of macrophages was prominently CD163+ in the RF/VE-TPGS0.50. Both the compounds showed favourable negative binding energies as expressed in terms of 'XP GScore'.
CONCLUSION: New formulations based on the incorporation of RF/VE-TPGS in universal adhesives may be of significant potential in facilitating penetration, distribution and uptake of riboflavin within the dentine surface.
OBJECTIVES: This paper focused on how the refractive index based nanobio-sensoring gold platform can produce more efficient, adaptable and more practical detection techniques to observe molecular interactions at high degree of sensitivity. It discusses surface chemistry approach, optimisation of the refractive index of gold platform and manipulation of gold geometry augmenting signal quality.
METHODS: In a normal-incidence reflectivity, r0 can be calculated using the Fresnel equation. Particularly at λ = 470 nm the ratio of r / r0 showed significant amplitude reduction mainly stemmed from the imaginary part of the Au refractive index. Hence, the fraction of reduction, Δr = 1 - r / r0. Experimentally, in a common reference frame reflectivity of a bare gold surface, R0 is compared with the reflectivity of gold surface in the presence of biolayer, R. The reduction rate (%) of reflectivity, ΔR = 1 - R / R0 is denoted as the AR signal. The method therefore enables quantitative measurement of the surface-bound protein by converting ΔR to the thickness, d, and subsequently the protein mass. We discussed four strategies to improve the AR signal by changing the effective refractive index of the biosensing platform. They are; a) Thickness optimisation of Au thin layer, b) Au / Ag bimetallic layer, c) composing alloy or Au composite, and d) Au thinlayer with nano or micro holes.
RESULTS: As the result we successfully 'move' the refractive index, ε of the AR platform (gold only) to ε = -0.948 + 3.455i, a higher sensitivity platform. This was done by composing Au-Ag2O composite with ratio = 1:1. The results were compared to the potential sensitivity improvement of the AR substrate using other that could be done by further tailoring the ε advanced method.
CONCLUSION: We suggested four strategies in order to realize this purpose. It is apparent that sensitivity has been improved through Au/Ag bimetallic layer or Au-Ag2O composite thin layer, This study is an important step towards fabrication of sensitive surface for detection of biomolecular interactions.
METHODS: Forty direct impressions of a mandibular reference model fitted with six dental implants and multibase abutments were made using VPES and PE, and implant casts were poured (N = 20). The VPES and PE groups were split into four subgroups of five each, based on splinting type: (a) no splinting; (b) bite registration polyether; (c) bite registration addition silicone; and (d) autopolymerizing acrylic resin. The accuracy of implant-abutment replica positions was calculated on the experimental casts, in terms of interimplant distances in the x, y, and z-axes, using a coordinate measuring machine; values were compared with those measured on the reference model. Data were analyzed using non-parametrical Kruskal-Wallis and Mann-Whitney tests at α = .05.
RESULTS: The differences between the two impression materials, VPES and PE, regardless of splinting type, were not statistically significant (P>.05). Non-splinting and splinting groups were also not significantly different for both PE and VPES (P>.05).
CONCLUSIONS: The accuracy of VPES impression material seemed comparable with PE for multi-implant abutment-level impressions. Splinting had no effect on the accuracy of implant impressions.