Background: Calcium hydroxide and calcium-silicate materials used as direct pulp capping materials. The aims of this in vitro study is to compare among these materials in, the calcium ion release and pH change in soaking water after immersion of materials’ specimens in deionized water. Also Solubility and water sorption of materials’ specimens measured after soaking time. Calcium-silicate materials used were Biodentine, TheraCal and MTA Plus. Materials and methods: Four materials used in this study; Urbical lining (as control group), Biodentine, TheraCal and MTA Plus. Ten discs fabricated from each tested material, by using plastic moulds of 9 mm diameter and 1 mm thickness. Each specimen was immersed in 10 ml of deionized water and stored at 37ºC using incubator for 3 hr, 24hr, 14 days and 30 days as a sequence. The amount of calcium ion (Ca+2) released in soaking water was measured in each tube using atomic absorption spectrophotometer. Also pH analysis for soaking water measured by using pH meter. For solubility and water sorption measurement, the specimen (n=10) weighed with precision weighing scale before immersion in deionzed water to determine the initial Weight (W1) and immediately after weighing immersed in 10 mL of deionized water at 37 °C for 1 week using an incubator, then removed and weighing again (W2). The samples blotted dry using filter paper and dehydrated in an oven at 37 °C for 24 hr. and weighed again (W3). Then percentage of solubility and water sorption were determined. Data obtained were analyzed using one-way ANOVA and Tukey tests at 0.05 significant levels. Results: Statistical analysis showed highly significant differences (P<0. 05) among tested materials and in all tests (Ca+2 release, pH change, solubility and water sorption). Biodentine showed higher calcium ion released at four soaking time (3 hr, 24hr, 14 days and 30 days), with non significant difference with TheraCal and highly significant difference with MTA Plus and control group at 24 hr. immersion time; While MTA Plus showed non significant difference with control group at 24 hr. Less amount of calcium released was in control group. All tested materials induced alkalization of the soaking water that decreased with time. Means of solubility and water sorption showed that MTA Plus and biodentine had higher solubility in comparison with control group, while TheraCal showed less solubility than control group. The results of water sorption showed that less sorption percentage occurred in control group in comparison with other groups. Conclusion: calcium-silicate materials released more Ca+2 with time than calcium hydroxide. TheraCal showed less solubility and higher water sorption in comparison with control group. Biodentine and MTA Plus showed higher solubility and water sorption in comparison with TheraCal and control group.
ABSTRACT Background:Hydrogen absorption and related degradation in the mechanical properties of Ni-Ti based orthodontic wires has been demonstrated following exposure to fluoride prophylactic agents. This study was designed to investigate the effects of three fluoride containing agents on the load deflection characteristics of heat activated nickel titanium arch wires during unloading phase. Material and method: Eighty specimens of heat activated nickel titanium arch wires were obtained from Ortho Technology Company, half of which had a 0.016 inch round and 0.019x0.025 rectangular. Ten specimens from both wire size were immersed in one of the tested fluoride prophylactic agents (neutral sodium fluoride gel, stannous fluoride gel or phos-flu
... Show MoreResin-modified glass ionomer cement tends to shrink due to polymerization of the resin component. Additionally, they are more prone to syneresis and imbibition during the setting process. This
ABSTRACT Background: Bracket rebonding is a common problem in orthodontics which may result in many drawbacks. The aims of this study were to evaluate the effects of application of two enamel protective agents “Icon†and “ProSeal†on shear bond strength before and after rebonding of stainless steel orthodontic brackets using conventional orthodontic adhesive and to assess the site of bond failure. Materials and methods: Fifty sound extracted human upper first premolar teeth were selected and randomly divided into two equal groups; the first time bonding and the rebonding groups (n=30). Each group was subdivided into control, Icon and ProSeal subgroups. The enamel protective agents were applied after etching (precondi
... Show MoreObjectives To tailor composites of polyethylene–hydroxyapatite to function as a new intracanal post for the restoration of endodontically treated teeth (ETT). Methods Silanated hydroxyapatite (HA) and zirconium dioxide (ZrO2) filled low-density polyethylene (LDPE) composites were fabricated by a melt extrusion process and characterised using infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). The flexural strength and modulus were determined in dry state and post ageing in simulated body fluid and fractured surfaces analysed by SEM. The water uptake and radiographic appearance of the experimental composites were also measured and compared with a commercially known endodontic fibre
... Show MoreVisceral leishmaniosis is one of the most fatal old-world neglected disease with estimated 90 thousand worldwide cases emerge each year. In Iraq, the cutaneous and visceral form are endemic but available chemotherapies are either toxic with diverse side effects, expensive available drugs or parasite …
Background: Restoration of root canal treated teeth with a permanent restoration affect in the success of endodontically treated teeth. This in vitro study was performed to evaluate and compare the fracture strength of endodontically treated teeth restored by using custom made zirconium posts and cores, prefabricated carbon fiber, glass fiber and zirconium ceramic posts. Materials and method: Forty intact human mandibular second premolars were collected for this study and were divided into five groups. Each group contains 8 specimens: Group1: Teeth restored with Carbon Fiber Posts; Group2: Teeth restored with Glass Fiber Posts; Group3: Teeth restored with Zirconium Ceramic prefabricated Posts; Group4: Teeth restored with Zirconium Posts
... Show MoreIntroduction: This study was designed to examine the effects of addition of the combination of polymerized polymethyl methacrylate (PMMA) and zirconia (ZrO2) particles to heat cure PMMA resin on impact strength, surface hardness, and roughness. Methods: The 70% (w/w) of polymerized PMMA powder (particle size: 0.70mm) was mixed with 30% (w/w) of zirconia powder (ZrO2) (1mm) to produce PMMA-ZrO2 filler. Ninety acrylic specimens created were divided into three groups containing 0% wt (Control group), 2% wt, and 4% wt, PMMA-ZrO2 filler. Ten specimens were used for impact strength, surface hardness and roughness test, blindly. Data were analyzed via oneway ANOVA and the Tukey post hoc test using R 3.6.3. Results: There was statistically signific
... Show MoreBackground: Recently epigenetic alterations have received increased attention because of theirimportant role in the process of tumerigenesis. It has been found that more than half of genetic changes were epigenetic. Epigenetic alterations are catalyzed by DNMTs enzymes. Increased knowledge about this molecular event may achieve progress in the war against cancer. The aim of this study was to evaluate and compare the expression of DNMT3B among oral, laryngeal and skin SCC. Materials and Methods: This study was performed on (120) formalin-fixed, paraffin-embedded blocks, histopathologically diagnosed as oral, laryngeal and skin SCC). Immunohistochemical staining of DNMT3B antibody was performed on each case of this study. Results: The immunoh
... Show MoreBackground: The Apgar score is calculated based on the five features: heart rate, reflexes, color, muscle tone, and respiratory effort. Each element is scored from 0 to 2, with a total probable score of 10 at 1 minute and 5 minute. Aim: To study the influence of gestational diabetes mellitus (GDM) and diabetes mellitus on APGAR score in neonate. Materials and methods: The samples were studied from Department of Obstetrics and Gynaecology in Al-Imamain Al-Kadhimiyain (AS) Medical city, Baghdad Teaching Hospital and Al-Karkh Maternity Hospital in the period between 1 December 2016 and 1 may 2017, after obtaining the approval from Iraqi Ministry of Health. A total of 102 neonates were included in this study which includes 34 neonates of mother
... Show MoreThe problem of constant and change values is one of the important problems that the philosophy thought had faced as the religious and social studies had taken it as it considers as one of the most dangerous which touch the basic . the research deals with the effect of change value of new Iraqi situation to be as an attempt , as participation or an excitement that can be occupied a space through the area of questions on the fix and change of moral values shed light on the economical ,social and political events that the Iraqi society passes through them .it is part of interests that becomes importance to everyone through the light of moral change Which is arbitrary to the life of the individual .It is not possible to rebuild the society o
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