scholarly journals A novel customized ceramic bracket for esthetic orthodontics: in vitro study

2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Liu Yang ◽  
Guangfu Yin ◽  
Xiaoming Liao ◽  
Xing Yin ◽  
Niansong Ye
Keyword(s):  
Shape Matching ◽  
Raw Materials ◽  
In Vitro Study ◽  
Frictional Resistance ◽  
Orthodontic Bracket ◽  
Wide Range ◽  
Ceramic Brackets ◽  
Orthodontic Patients ◽  
Ceramic Bracket

Abstract Background This study aims to develop a novel process to establish a standardized manufacturing technique of customized esthetic ceramic bracket system (CCB) which could be endowed with individual color and shape to satisfy patients’ individual demands. Material characteristics and mechanical parameters of CCB were evaluated. Subjects and methods CCB virtual models were designed individually according to patient’s teeth morphology and clinical demands. 3D printing technology, lost-wax technology, and selected glass-ceramic ingots were employed to fabricate CCB. Scanning electron microscopy (SEM) analyses were performed to characterize the surface morphology of CCB and commercially available brackets (Clarity Advanced; Crystalline VII; Inspire ICE; Damon Q). Static and kinetic frictional resistance (FR), shear bond strength (SBS) and adhesive remnant index (ARI) scores were recorded. One-way analyses of variance (ANOVA) and post-hoc Tukey’s HSD multiple tests were used for statistical analyses. Results Multi-color and multi-transparency raw materials facilitated CCB with a wide range of color options and controllable optical properties to satisfy different esthetic demands of individual orthodontic patients. CCB presented same level of FR as commercially available ceramic brackets did. No significant differences (P ≥ 0.05) of SBS were observed among CCB-ES (treated silane), Clarity Advanced and Crystalline VII groups, and CCB-E (no silane) attained the highest ARI mean score 3. In the preliminary clinical trial, CCB presented excellent color-matching and shape-matching appearances similar to natural teeth, which made it highly invisible from social intercourse distance. Conclusions CCB were demonstrated to be an applicable labial orthodontic bracket system with optimized esthetics and biomechanics. We envision that it would be an ideal alternative for patients who pursue esthetic orthodontic treatment but were not likely to take lingual appliances or clear aligners.

The Influence of Bracket Material, Ligation Force and Wear on Frictional Resistance of Orthodontic Brackets

1993 ◽  
Vol 20 (2) ◽  
pp. 109-115 ◽  
Author(s):  
O. Keith ◽  
S. P. Jones ◽  
E. H. Davies
Keyword(s):  
Stainless Steel ◽  
Abrasive Wear ◽  
Single Crystal ◽  
Wear Debris ◽  
Aluminium Oxide ◽  
Frictional Resistance ◽  
Material Force ◽  
Orthodontic Bracket ◽  
Ceramic Brackets ◽  
Ceramic Bracket

Planar static frictional phenomena were investigated for two types of ceramic and one type of stainless steel orthodontic bracket against rectangular stainless steel archwire. The brackets studied were ‘Starfire’ (single crystal aluminium oxide), ‘Allure III’ (polycrystalline aluminium oxide), and ‘Dentaurum’ (stainless steel). The investigative parameters were: bracket material, force of ligation and whether the brackets were new or ‘worn’. Without exception, both types of ceramic bracket produced greater frictional resistance than the stainless steel brackets throughout testing. At a ligation force of 500 g, the Starfire bracket gave the greatest frictional resistance. At ligation forces of 200 and 50 g, the greatest frictional resistance was seen with Allure III. After a period of simulated wear, frictional resistance of Starfire tended to increase at the greatest ligation load while that of both ceramics decreased slightly at the two lower ligation loads. The ceramic brackets caused abrasive wear of the archwire surfaces and the consequent wear debris may have contributed to the changes in frictional resistance seen with Starfire and Allure III. Dentaurm brackets produced minimal frictional resistance in any test and negligible change with wear.

scholarly journals Comparative Evaluation of Frictional forces between different Archwire-bracket Combinations

2014 ◽  
Vol 4 (1) ◽  
pp. 22-28 ◽  
Author(s):  
Vinit Singh ◽  
Swati Acharya ◽  
Satyabrata Patnaik ◽  
Smruti Bhusan Nanda
Keyword(s):  
Stainless Steel ◽  
Tooth Movement ◽  
Testing Machine ◽  
Frictional Resistance ◽  
Nickel Titanium ◽  
Orthodontic Bracket ◽  
Fixed Appliance ◽  
Beta Titanium ◽  
Frictional Forces

Introduction: During sliding mechanics, frictional resistance is an important counterforce to orthodontic tooth movement; whichmust be controlled to allow application of light continuous forces.Objective: To investigate static and kinetic frictional resistance between three orthodontic brackets: ceramic, self-ligating, andstainless steel, and three 0.019×0.025” archwires: stainless steel, nickel-titanium, titanium-molybdenum.Materials & Method: The in vitro study compared the effects of stainless steel, nickel-titanium, and beta-titanium archwires onfrictional forces of three orthodontic bracket systems: ceramic, self-ligating, and stainless steel brackets. All brackets had 0.022”slots, and the wires were 0.019×0.025”. Friction was evaluated in a simulated half-arch fixed appliance on a testing machine. Thestatic and kinetic friction data were analyzed with 1-way analysis of variance (ANOVA) and post-hoc Duncan multiple rangetest.Result: Self-ligating (Damon) brackets generated significantly lower static and kinetic frictional forces than stainless steel (Gemini)and ceramic brackets (Clarity). Among the archwire materials, Beta-titanium showed the maximum amount of frictional forceand stainless steel archwires had the lowest frictional force.Conclusion: The static and kinetic frictional force for stainless steel bracket was lowest in every combination of wire.

Comparison of friction of metallic and ceramic brackets during sliding mechanics after prophylaxis with sodium bicarbonate jet: An in vitro study

2021 ◽  
Author(s):  
Aline Rosa Galavotti Viana ◽  
Diego Patrik Alves Carneiro ◽  
Pricila Alves Carneiro ◽  
Américo Bortolazzo Correr ◽  
Silvia Amélia Scudeler Vedovello ◽  
...  
Keyword(s):  
Sodium Bicarbonate ◽  
In Vitro Study ◽  
Vitro Study ◽  
Ceramic Brackets ◽  
Sliding Mechanics

scholarly journals Cellular effects of glycine and trehalose air-polishing powders on human gingival fibroblasts in vitro

2021 ◽  
Author(s):  
Jens Weusmann ◽  
James Deschner ◽  
Jean-Claude Imber ◽  
Anna Damanaki ◽  
Natalia D. P. Leguizamón ◽  
...  
Keyword(s):  
Wound Healing ◽  
Cell Function ◽  
Nuclear Translocation ◽  
In Vitro Study ◽  
Human Gingival Fibroblasts ◽  
Mrna Levels ◽  
Gingival Fibroblasts ◽  
Air Polishing ◽  
Wide Range

Abstract Objectives Air-polishing has been used in the treatment of periodontitis and gingivitis for years. The introduction of low-abrasive powders has enabled the use of air-polishing devices for subgingival therapy. Within the last decade, a wide range of different low-abrasive powders for subgingival use has been established. In this study, the effects of a glycine powder and a trehalose powder on human gingival fibroblasts (HGF) were investigated. Methods HGF were derived from three systemically and periodontally healthy donors. After 24 h and 48 h of incubation time, mRNA levels, and after 48 h, protein levels of TNFα, IL-8, CCL2, and VEGF were determined. In addition, NF-κB p65 nuclear translocation and in vitro wound healing were assessed. Statistical analysis was performed by ANOVA and post hoc Dunnett’s and Tukey’s tests (p < 0.05). Results Glycine powder significantly increased the expression of proinflammatory genes and showed exploitation of the NF-κB pathway, albeit trehalose powder hardly interfered with cell function and did not trigger the NF-κB pathway. In contrast to trehalose, glycine showed a significant inhibitory effect on the in vitro wound healing rate. Conclusion Subgingivally applicable powders for air-polishing devices can regulate cell viability and proliferation as well as cytokine expression. Our in vitro study suggests that the above powders may influence HGF via direct cell effects. Trehalose appears to be relatively inert compared to glycine powder.

Thermal debonding of ceramic brackets: An in vitro study

1997 ◽  
Vol 111 (2) ◽  
pp. 163-172 ◽  
Author(s):  
Marguerite Crooks ◽  
James Hood ◽  
Michael Harkness
Keyword(s):  
In Vitro Study ◽  
Vitro Study ◽  
Ceramic Brackets

scholarly journals Enamel loss following ceramic bracket debonding: A quantitative analysis in vitro

2014 ◽  
Vol 85 (4) ◽  
pp. 651-656 ◽  
Author(s):  
Sam N. Suliman ◽  
Terry M. Trojan ◽  
Daranee Tantbirojn ◽  
Antheunis Versluis
Keyword(s):  
Standard Deviation ◽  
Three Dimensions ◽  
Optical Scanner ◽  
Polycrystalline Ceramic ◽  
Tooth Surfaces ◽  
Ceramic Brackets ◽  
Successful Removal ◽  
Ceramic Bracket ◽  
Surface Changes

ABSTRACT Objective:  To measure enamel surface changes after ceramic bracket debonding and after cleanup. Materials and Methods:  Forty extracted teeth were scanned in three dimensions using an optical scanner (baseline). Two ceramic bracket systems were placed (19 metal-reinforced polycrystalline ceramic brackets; 21 monocrystalline ceramic brackets). Seven days later, brackets were debonded and teeth scanned (post-debond). Adhesive remnants and bracket fragments were recorded. Tooth surfaces were cleaned using a finishing carbide bur and scanned again (post-cleanup). Post-debond and post-cleanup scans were aligned with the baseline, and surface changes were quantified. Results were statistically compared using t-tests and Mann-Whitney tests (α  =  .05). Results:  The depth of enamel loss (mean ± standard deviation) post-debond was 21 ± 8 µm and 33 µm and post-cleanup was 28 ± 14 µm and 18 ± 8 µm (P  =  .0191); the post-debond remnant thickness was 188 ± 113 µm and 120 ± 37 µm (P  =  .2381) and post-cleanup was 16 ± 5 µm and 15 µm for polycrystalline and monocrystalline ceramic brackets, respectively. The monocrystalline ceramic brackets predominantly left all adhesive on the tooth; the polycrystalline ceramic brackets were more likely to leave bracket fragments attached. Conclusion:  Both systems allowed successful removal of the brackets with minimal enamel loss. However, the polycrystalline ceramic brackets left more fragments on the tooth, which complicated cleanup efforts.

Diallyl Disulfide Attenuates Methotrexate-Induced Hepatic Oxidative Injury, Inflammation and Apoptosis and Enhances its Anti-tumor Activity

2021 ◽  
Vol 14 ◽  
Author(s):  
Marwa M. Khalaf ◽  
Emad H.M. Hassanein ◽  
Abdel-Gawad S. Shalkami ◽  
Ramadan A.M. Hemeida ◽  
Wafaa R. Mohamed
Keyword(s):  
Cytotoxic Activity ◽  
Caspase 3 ◽  
In Vitro Study ◽  
Diallyl Disulfide ◽  
Sod Activity ◽  
Cytotoxic Effects ◽  
Wide Range ◽  
Anti Tumor Activity ◽  
Mcf 7

Background: Methotrexate (MTX) is used potently for a wide range of diseases. However, hepatic intoxication by MTX hinders its clinical use. Objectives: The present study was conducted to investigate the diallyl disulfide (DADS) ability to ameliorate MTX-induced hepatotoxicity. Methods: Thirty-two rats were randomly divided into four groups: normal control, DADS (50 mg/kg/day, orally), MTX (single i.p. injection of 20 mg/kg) and DADS+MTX. Liver function biomarkers, histopathological examinations, oxidative stress, inflammation, and apoptosis biomarkers were investigated. Besides, an in vitro cytotoxic activity study was conducted to explore the modulatory effects of DADS on MTX cytotoxic activity using Caco-2, MCF-7, and HepG2 cells. Results: DADS significantly reduced the increased serum activities of ALT, AST, ALP, and LDH. These results were confirmed by the alleviation of liver histopathological changes. It restored the decreased GSH content and SOD activity, while significantly decreased MTX-induced elevations in both MDA and NO2- contents. The hepatoprotective effects were mechanistically mediated through the up-regulation of hepatic Nrf-2 and the down-regulation of Keap-1, P38MAPK, and NF-κB expression levels. In addition, an increase in Bcl-2 level with a decrease in the expression of both Bax and caspase-3 was observed. The in vitro study showed that DADS increased MTX anti-tumor efficacy. Conclusions: DADS potently alleviated MTX-induced hepatotoxicity through the modulation of Keap-1/Nrf-2, P38MAPK/NF-κB and apoptosis signaling pathways and effectively enhanced the MTX cytotoxic effects, which could be promising for further clinical trials.

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