Background: Prophylaxis methods are used to mechanically remove plaque and stain from tooth surfaces; such methods give rise to loss of superficial structure and roughen the surface of composites as a result of their abrasive action. This study was done to assess the effect of three polishing systems on surface texture of new anterior composites after storage in artificial saliva. Materials and methods: A total of 40 Giomer and Tetric®N-Ceram composite discs of 12 mm internal diameter and 3mm height were prepared using a specially designed cylindrical mold and were stored in artificial saliva for one month and then samples were divided into four groups according to surface treatment: Group A (control group):10 specimens received no surface polish and were subdivided into A1 (Giomer) and A2 (Tetric®N-Ceram). Group B: 10 specimens received polishing with Air polishing devise (APD) and were subdivided into B1 (Giomer) and B2 (Tetric®N-Ceram). Group C: 10 specimens received polishing with pumice and brush and were subdivided into C1 (Giomer) and C2 (Tetric®N-Ceram). Group D: 10 specimens were polished with pumice and rubber cup and were subdivided into D1 (Giomer) and D2 (Tetric®N-Ceram). Testing was done by means of profilometer and statistically analyzed using analysis of variance test (ANOVA), LSD and student t-test. Also samples were photographed by special orthoplane camera using light polarizing microscope. Results: The results showed a highly statistical significant difference in surface roughness among Giomer subgroups P<0.05. Also there was a highly significant difference P<0.05 when comparing Tetric subgroups according to type of surface treatment. Furthermore there was non-significant difference P>0.05 between groups according to the type of restorative material used. Conclusion: The use of prophylactic surface treatment significantly increased Giomer and Tetric ceram surface roughness and the use of rotating brush has shown the roughest surface among all other types of prophylactic protocols also Giomer had shown more surface roughness than Tetric ceram although the difference was not significant.
Numerous drilling additives and materials are used continuously because they are necessary to support and give the required properties of the drilling fluid so that to ensure the stability of the borehole. This paper aspires to evaluate the rheological properties of bentonite (montmorillonite) Trefawey as an alternative to using commercial bentonite. Monitoring and evaluating of the rheological and filtration properties were prepared. This exertion aims to focus on the effect of hematite, and barite on the rheological properties of the three aforementioned bentonite types. An improvement in the rheological properties of bentonite (montmorillonite). Trefawey was observed after adding the previous heavy materials. Hematite has by some
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Carnosol, a phenolic diterpene, is one of the effective anticancer agents naturally occurring in rosemary, sage, parsley, and oregano. The chemoresistance problem increased with the routinely used chemotherapy. Therefore, the efforts to find a substitute with safe and low cost have become crucial worldwide. The current study attempts to inspect the anticancer molecular mechanisms of Carnosol on modulating up- and down- regulation of multiple genetic carcinogenesis pathways. The cytotoxicity of Carnosol on Hela cells was evaluated by MTS assay. Flow cytometry was used to assess apoptosis and cell cycle arrest. The apoptotic morphological changes were obvious by dual apoptosis assay. The differential gene expression after treatment wi
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Background: The fracture of instruments within root canal during endodontic treatment is a common incidence, fracture because of fatigue through flexure occurs due to metal fatigue, this study aimed to assess the effect of curvature angle and rotational speed on the cyclic fatigue of different type of Endodontic NiTi Rotary Instruments and compare among them. Materials and method: Three types of rotary instruments with tip size 0.25: ProTaPer F2 (Densply, Malifier) Revo-S SU( 0.06 taper, MicroMega) and RaCe system (0.06 taper, FKG, Dentaire), Forty file of each instrument were used within two canals with angle of curvature (40 &60 )at two speed (250&400)RPM, twelve group were formed for all instruments(total number=120),ten file fo
... Show MoreBackground: Denture lining materials are widely used in prosthodontic treatment and management of traumatized oral mucosa. A contaminated prosthesis can provide a source of cross-contamination between patients and dental personnel as well as a cause for denture stomatitis. Therefore, denture disinfection has been recommended as an essential procedure for maintenance of a healthy oral mucosa. This study investigated the effect of SOLO disinfectant solution on some properties of different denture lining materials. Materials and methods: Three different solutions were used in this study; SOLO disinfectant solution, sodium hypochlorite solution, and water on three types of acrylic denture lining materials; hot cure, cold cure, and soft acrylic
... Show MoreThe objective of this work was to determine and compare the physiological changes in some: blood components (packed cell volume and hemoglobin) and plasma biochemical parameters (glucose, total protein, albumin, cholesterol and triglycerides) under 3 day of different types of stress: water deprivation, starvation, overcrowding and handling stress. Twenty five male Wister rats weighted 100-120 gm, were divided randomly into five groups: control, water deprivation, starvation, overcrowding and handling stress. On the third day of stress the animals anesthetized for blood collection; the results of blood component revealed a significant increase in PCV and a significant decrease in Hb of water deprivation group and starva
... Show MoreBackground: Elastomeric chains are one of the most commonly used force delivery systems. They have the ability to exert a continuous force, convenience of use, compatibility to oral environment and cost effectiveness but one of the inherited disadvantages is force degradation. Materials and methods: This in vitro study was designed to evaluate the effect of alcohol presence in mouthwashes on force decay of different configurations of clear elastomeric chains from (Ortho Technology company) which are: closed , short and long under the effect of time at (Initial, 1, 2, 3 and 4 weeks) intervals with exposure to different chemical solutions. A total (540) modules of elastomeric chains of three different types (long, short and closed) trans
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The Effect of Chicken Eggshell Extract on Microhardness of Artificially Induced Dental Erosion in Permanent Teeth (In Vitro Study), Shatha A Abbas*, Alhan A Qasim
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Background: Sealers should demonstrate adhesive properties to dentin, decreasing the chance of endodontic treatment failure. Increased adhesive properties to dentin may lead to greater strength of the restored tooth, which may provide greater resistance to tooth fracture and clinical longevity of an endodontically treated tooth. The aim of this study was to evaluate the shear bond strength of Bioceramic iRoot SP sealer, AH plus sealer and Apexit plus sealer in absence or presence of smear layer using push out bond strength test. Materials and Methods: Sixty straight single roots of the mandibular premolars were selected for this study. All canals were instrumented using ProTaper rotary instruments to achieve tapered canal walls, instrumenta
... Show MoreObjective: To evaluate and compare the effect of mechanical surface treatment (groove, aluminum oxide particles)
with 45 degree bevel type of joint on tensile bond strength of acrylic specimens repaired by two curing methods
(microwave and water both).
Methodology: Eighty specimens (80) were prepared from pink heat cure acrylic resin. They were divided into two
main groups (40 specimen repaired by microwave energy and 40 specimens repaired by water bath method).Each
group can be divided into four subgroups of ten according to the surface treatment. The control group A was left
intact, group B received no surface treatment, group C and D received surface treatment by (groove, 50 m aluminum
oxide particles). Specimens