Background: The ideal maxillofacial prosthesis should have fine and thin boundaries that bindwith the surrounding facial structures and possess high tear strength.This study aims to determinethe best percentages of nanofiller (TiO2) and intrinsic pigment (silicone functional intrinsic) thatcould be mixed in as additives to improve the tear strength of Cosmesil M511 andVST50F siliconeelastomers with the least effect on their hardness.Materials and Methods: In this in vitro experimental study, a total of 80 samples, 40 for eachelastomer, were fabricated. Each elastomer sample was split into two equal groups to test for tearstrength and Shore A hardness. Each group consisted of 20 samples, including 10 control sampleswithout additives and 10 experimental samples with additives (mixtures of 0.2 wt% nano‑TiO2 + 0.25wt% intrinsic pigment and 0.25 wt% nano‑TiO2 + 0.25 wt% intrinsic pigment for the CosmesilM511 and VST50F silicone elastomers, respectively).Two‑way ANOVA and Tukey test were usedfor comparison; P < 0.05 was considered statistically significant.Results: Significant differences in tear strength were found among all tested groups (P < 0.05).The tear strength of the experimental subgroups significantly increased compared with the controlsubgroups (P < 0.05). Significant differences in Shore A hardness were also observed among alltested groups (P < 0.05) except between the experimental subgroups of both materials, where anonsignificant difference was obtained (P > 0.05).Conclusion: Incorporation of select percentages of TiO2 nanofiller and intrinsic pigment intoCosmesil M511 andVST50F silicone elastomers yields improvements in tear strength with a slightincrease in hardness (PDF) Impact of a mixture of nanofiller and intrinsic pigment on tear strength and hardness of two types of maxillofacial silicone elastomers. Available from: https://www.researchgate.net/publication/343647971_Impact_of_a_mixture_of_nanofiller_and_intrinsic_pigment_on_tear_strength_and_hardness_of_two_types_of_maxillofacial_silicone_elastomers [accessed Apr 05 2023].
Abstract
In the present work the effect of bearing compliance on the performance of high speed misaligned journal bearing lined with a compliant PTFE liner lubricated with bubbly oil at high speeds has been studied. The effect of induced oil film temperature due to shearing effect has been implemented. Hydrodynamic effect of the complaint bearing and the influence of aerated oil have been examined by the classical thermohydrodynamic lubrication theory modified to include the effect of oil film turbulence and oil film temperature with suitable models for bubbly oil viscosity and density. The effect of liner elastic deformation has been implemented by using Winkler model. The effects of variable density and s
... Show MoreBackground: This study aimed to compare the surface microhardness (MH) and mineral content of white spot lesions(WSLs) after using bioactive glass (BAG)casein phosphopep-tides-amorphous calcium phosphate(CPP-ACP),and nanohydroxyapatite(Nano-HAP) under pHcycling. Material and method:18 sound maxillary first premolar were used for the study.10 were selected for the vickers microhardness test, For Energy-dispersive X-ray spectroscopy analysis (EDX), the remaining 8 premolar teeth were used, 40 sections of enamel blocks (Four from each tooth) were produced from the middle part of the buccal and palatal surfaces of teeth for MH test while 48 sections of enamel blocks (Six from each tooth) were produced for EDX analysis. Enamel slabs were
... Show MoreThe aim of this research is to identify the effect of Webinar technique on digital culture in the College of Education for pure sciences at Ibin Haitham, University of Baghdad. The research samples consisted of (68) male and female students from the Chemistry Department who are following classes during the (2019- 2020) academic year. The samples represent (42%) of the total number of (162) students split into control and experimental groups. For this purpose, the scientific contents for testing were determined. The experimental part is based on analysis of the results from experiments in (preliminary standard solutions, refractive index, Beer-Lambert law). To achieve the aim of the research in testing the measure of student's digital cultur
... Show MoreThis work deals with the production of light fuel cuts of (gasoline, kerosene and gas oil) by catalytic cracking treatment of secondary product mater (heavy vacuum gas oil) which was produced from the vacuum distillation unit in any petroleum refinery. The objective of this research was to study the effect of the catalyst -to- oil ratio parameter on catalytic cracking process of heavy vacuum gas oil feed at constant temperature (450 °C). The first step of this treatment was, catalytic cracking of this material by constructed batch reactor occupied with auxiliary control devices, at selective range of the catalyst –to- oil ratio parameter ( 2, 2.5, 3 and 3.5) respectively. The conversion of heavy vacuum gas
... Show MoreMyelosuppression is one of the serious adverse effects of cancer chemotherapy that lead to life threatening febrile neutropenia and considered a limiting factor for successful therapy. Cyclophosphamide a widely used anticancer drugs, induces severe bone marrow suppression by damaging hematopoietic stem cells. As cancer incidence expands globally, the demand for an effective myeloprotective therapy during cancer treatment is also increasing.Nigella sativa seed oil, a well-known plant extract that widely used for various health conditions. This study aims to evaluate the myeloprotective activity of Nigella sativa seed oil in cyclophosphamide-induced myelosuppression mice model. Myelosuppression induced by single intraperitoneal injection o
... Show MoreThe long – term behaviour of polyethylene products used out doors is affected by weathering. In the present work,
weathering test was carried out to find the effect of the environment conditions on the mechanical properties of
HDPE/LLDPE blends with different weight percents (0, 15, 30, and 45 %) relative to the LLDPE by increasing the
exposure times to (100, 150, 200, 250, 300) hr.
A series of tests (destructive), tensile, impact and hardness were carried out on the prepared samples, the results
obtained declare the changes on the material behaviour from ductile to brittle and the polymer shows a decline in the
mechanical properties with increasing the exposure times.
In the present work empirical equations were r
This study offers the elastic response of the variable thickness functionally graded (FG) by single walled carbon nanotubes reinforced composite (CNTRC) moderately thick cylindrical panels under rotating and transverse mechanical loadings. It’s considered that, three kinds of distributions of carbon nanotubes which are uniaxial aligned in the longitudinal direction and two functionally graded in the transverse direction of the cylindrical panels. Depending on first order shear deformation theory (FSDT), the governing equations can be derived. The partial differential equations are solved by utilizing the technique of finite element method (FEM) with a program has been built by using FORTRAN 95. The results are calculat
... Show MoreObjectives: To identify the effectiveness of instructional program concerning premarital screening of sexual transmitted disease on student's knowledge at Baghdad University and examine the relationship between students' knowledge and certain studied variables. And hypothesis for this study; There is a difference in university student’s knowledge toward premarital screening between pre and posttests of instructional program. Methodology: A quasi-experimental design (pretest-posttest approach) was conducted at six colleges and its college of education ibn rushd, college of political science, college of law, college of literatur