bluuebunny/crossref_metadata_2025 huggingface dataset:
Smartphone Affordance: Achieving Better Business through Innovation: Cross Industry: Cross Border
Authors: Carayannis Elias G. , Clark Stephen C. , Valvi Dora E. , Stone Suki , Sharifrazi Farnaz
Published: December 2012

This paper is a pilot study using qualitative analysis to obtain concepts related to individual perceptions of Chief Executive Officers within various industries internationally. These concepts are related to emerging technologies such as mobile devices and their usefulness within a business and personal context. Technology has played a role in human affairs including business for millennia – starting with the lighting of the first fire, the carving of ideograms on the walls of caves and inventing the first round artifact that would eventually serve as a wheel. This research has empirically documented the ways and means that mobile technologies and “Smart-phones” impact an executive’s productivity and efficiency at work by conducting a series of opened ended interviews. Our findings further corroborate the presence, role and impact of what we call “happy accidents” in terms of strategic knowledge serendipity and arbitrage (SKARSE™) as factors shaping and even driving choices made by business leaders with strategic intent and implications.
An Investigation of the Behaviour of Magnetorheological Fluids in the Rotary Shock-Absorber
Authors: Kciuk Sławomir , Kciuk Monika , Turczyn Roman , Martynowicz Paweł
Published: December 2012

The main aim of the article was to present the investigation results of created megnetorheological fluids using carbonyl iron (CI) particles and analyse their behaviour in terms of the internal structure formation by a control of external magnetic field. Results of the experimental studies of a prototype magnetorheological rotary shock-absorber at various magnitudes of control current was presented in this paper.
Influence of Heat Treatment on the Damping Capacity of Fe-Ga Wires
Authors: Fang Mei Ling , Zhu Jie , Li Ji Heng , Gan Chao , Li Ming Ming , Gao Xue Xu
Published: December 2012

The influence of heat treatment on damping capacity of (Fe83Ga17)99.5B0.5 wires was investigated using a computer-controlled automatic inverted torsion pendulum. The measurements have been carried out as a function of strain amplitude in free-decay mode. The microstructures of (Fe83Ga17)99.5B0.5 wires were also investigated to clarify the effects of heat treatment on the damping capacity. The results show that the annealing temperature affects the damping capacity of (Fe83Ga17)99.5B0.5 wires by varying the grain size. With increasing annealing temperature, the damping capacity is enhanced and becomes more sensitive to strain amplitude. There is no obvious difference in the structure of (Fe83Ga17)99.5B0.5 wires with different cooling rate which indeed affects the damping properties. Large cooling rate will help to get higher damping capacity. The Fe-Ga alloys show certain damping capacity and are worth paying close attention to enhance this property so as to get access to the field of unwanted noise and vibration reduction applications.
Research on Microwave Absorbing Properties of Multi-Walled Carbon Nanotubes-Reinforced Cement-Based Composites
Authors: Wang Bao Min , Guo Zhi Qiang , Han Yu , Zhang Yuan , Ma Hai Nan
Published: December 2012

The microwave absorbing properties of multi-walled carbon nanotubes-reinforced cement-based composites (MWCNTs/CC) in the range of 2–18 GHz were investigated in this paper. MWCNTs with the addition of 0.08% by mass of cement were incorporated to cement mortar. It is shown that MWCNTs which act as microwave absorber reinforce the microwave absorbing properties of MWCNTs/CC. Two absorbing peaks of MWCNTs/CC appear in the range of 4–8 GHz, one lies in 4.9 GHz with the reflectivity of -29.1 dB and the other lies in 6.8 GHz with the reflectivity of - 19.2 dB, indicating that the absorbing properties of the composites are improved greatly.
Wood Powder Coated with Carboxymethylcellulose for Papermaking
Authors: Sun Xian Qi , Zhao Chuan Shan , Yu Jin Jin
Published: December 2012

Wood powder is widely used in production of wood-plastic composite materials, paint, animal feed, etc. In this paper, shape features of wood powder were analyzed and its performance in papermaking was tested. Based on the theoretical basis of deposition technique and electrostatic attraction mechanism between cationic ion and anionic ion, wood powder was coated with carboxymethylcellulose. And, then, the charge reversal has occurred on the wood powder with aluminum sulfate and polyamide polyamine epichlorohydrin. Coated wood powder can be more easily adsorbed on the fiber due to anionic charge. The experimental results show that the papermaking performance of wood powder is improved by coating with carboxymethylcellulose. The wood powder can be used in papermaking by appending a certain percentage of bleached kraft pulp. The bulkiness of paper presents an increasing trend with the increasing of wood powder addition. However the tensile index of paper has a certain decreased. Its physical property is suited to usage.
Calculation Model for Wellbore Pressure and Temperature in Heavy Oil Wells Considering of Non-Equilibrium Phenomenon
Authors: Zhao Rui Dong , Xiong Chun Ming , Zhang Jian Jun , Tao Zhen , Shi Jun Feng , Wu Xiao Dong , Zhang Xi Shun
Published: December 2012

At present the concept of instantaneous equilibrium is often adopted for simulating the wellbore pressure and temperature distribution in heavy oil wells. In this paper, the mathematical model was built and the diffusion of gas in the oil phase was researched. It proves that the non-equilibrium phenomenon is not obvious in convenient oil wells and it could be overlooked, while in heavy oil wells the non-equilibrium phenomenon is too prominent to be overlooked. Basing on the mass conservation principle, the momentum conservation principle and the energy conservation principle, the calculated model for wellbore pressure and temperature in heavy oil wells considering of the non-equilibrium effect was established. One example shows that the model can accurately reflect the flowing laws in heavy oil wells, which has a relative value for engineering.
Research on Mining Technological Parameters of 7# Thin Coal Seam in Liuquan Mine
Authors: Zhang Dong Sheng , Wang Xu Feng , Zhang Yang , Wang Jin Liang
Published: December 2012

Aimed at the specific geological conditions of 7# thin coal seam in Liuquan Mine, this paper used the methods of numerical calculation and theoretical analysis to determine the reasonable technological parameters of high-grade conventional mining face. The numerical simulation software of UDEC (Universal Distinct Element Code) was used to contrast and analyse the characteristics of surrounding rock stress distribution and overlying rock horizontal displacement under the condition of different length of coalface, then it was indicated that the surrounding rock deformation was less when length of coalface was 110 m which was advantageous for roof control; according to the conditions of roof and floor, the roof support strength was being calculated systematically to determine the row space of props being 700×1200 mm; the main equipments of coalface was assorted, and reasonable work manner in coalface and gob processing measure was put forward, which provided guidance for efficient mining in thin coal seam.
Study of the Main Influence Factors on Compression Set of PTMG Based Polyurethane Elastomer
Authors: Yi Yu Hua , Ma Rong Yao
Published: December 2012

The present study described the effect of the different synthetic methods, hard segment types, chain extension coefficient and the starting NCO/OH molar ratio on the compression set and the other properties of castable polyurethanes based on polytetrahydrofuran glycol (PTMG).The result showed that the system of PTMG/TDI/MOCA prepared by a quasi-prepolymer method and with the starting molar ratio of TDI to PTMG of 6:1 exhibits lower compression set.
Adsorption Mechanism of Humic Acid on Attapulgite Based on Stumm-Schindle Surface Complexation Model
Authors: Sun Nan , Yu Shui Li
Published: December 2012

Attapulgite from Xuyi in Jiangsu was characterized by X-ray spectrometer and FT-IR spectrophotometer, the coordination reaction degree of attapulgite/water interface and adsorption mechanism of humic acid(HA) on attapulgite was analyzed by Stumm-Schindle(SS) surface complexation model. The results showed that the main component of attapulgite is magnesia-alumina acid salt, the surface charge on attapulgite adapted from hydrolysates of Si-O and Al-O broken bond. After adsorption, zeta potential decreased firstly and then increased with ionic strength increasing, reduced with a pH value increasing. The zero point charge (pHzpc) of attapulgite was about 4~5, zeta potential and adsorption capacity reached the maximum values when pH= 4 and the minimum values when pH=12. The adsorption capacity increased with ionic strength rising. SS surface complexation model could well explain attapulgite / water interfacal coordination reaction, ionic strength can promote the interfacial coordination reaction and reduce electrostatic repulsion effects on adsorption, which has a definite theoretical and practical significance for guiding adsorption experiment and application of attapulgite in water-treatment technology.
Effect of Nanotube Aspect Ratio on Chemical Vapour Sensing Properties of Polymer/MWCNT Composites
Authors: Sakale G. , Jakovlevs D. , Aulika I. , Knite Maris
Published: December 2012

The main topic of this paper is the study of polyisoprene-multi wall carbon nanotubes (PiMWCNT) composites electrical conductivity and volatile organic compound sensing properties with respect to type of multi wall carbon nanotubes used. Electrical percolation parameters like percolation threshold and critical exponent of produced composites are determined and analyzed. PiMWCNT composites exhibit a promising sensitivity to the presence of volatile organic compounds. Therefore the composites sensing mechanism of volatile organic compounds are analyzed in more detail by applying an original measuring technique which enables simultaneous measurement of an electrical resistance, mass and length change measurement of the sample in the presence and subsequent absence of a vapour. Measurement results enabled the evaluation of both vapour diffusion behavior in the composite and electrical resistance change mechanism.
Influence of ZrO2 Nanoparticles Including SDS and CTAB Surfactants Assembly on the Interfacial Properties of Liquid-Liquid, Liquid-Air and Liquid-Solid Surface Layers
Authors: Esmaeilzadeh Pouriya , Fakhroueian Zahra , Bahramian Alireza , Arya Sharareh
Published: December 2012

This work investigates the effects of nanometric (5-8 nm) ZrO2 nanoparticles on adsorption of two surfactants, SDS (sodium dodecyl sulfate) and C12TAB (dodecyl trimethyl ammonium bromide) into oil/water, air/water and solid/water interfaces. Increasing the concentration of nanoparticles reduces the interfacial tension and surface tension of SDS at low surfactant concentration (< cmc) but it has a minor effect on interfacial and surface tension of C12TAB. Repulsive columbic interactions between SDS molecules and nanoparticles can cause the higher adsorption of surfactant at the oil/water interface. Adsorption of both surfactants on carbonate rock increases by adding nanoparticles to the system. This possibly happened because of the formation of surfactant-nanoparticle negatively charged aggregates that tend to adsorb on positively charged surface layer of carbonate rock. ZrO2 nanoparticles are surface active at the oil/water interface too, as the results of interfacial tension indicate they can decrease the n-heptane/water IFT about 14 units.
Characterization of Welded Components Flaws Using an Ultrasonic Expert System Based on Static Patterns
Authors: Zolfaghari Abolfazl , Shahriari Davood , Masoumi Fatemeh
Published: December 2012

Ultrasonic testing of welds is a nondestructive evaluation method in which high-frequency sound waves are introduced into materials for the detection of imperfections or flaws in the material. These sound waves travel through the material and are reflected at interfaces such as surface boundaries, grain boundaries, cracks, and pores. The reflected acoustic energy is converted to electrical signals that are recorded and analyzed to determine the presence and location of flaws or discontinuities. The objective of this study is to present an expert system according to static patterns in pulse-echo inspection. It determines numbers, locations and types of weld defects based on DIN EN 1713. This paper gives a brief outline of how the expert system algorithm operates to identify a number of defect scenarios. Since the proposed algorithm is verified by experiments, it allows the user to automatically address and interpret any defects.
Research of Calcium Oxide Based Ceramic Cores in Titanium Casting
Authors: Xu Xiao Qing , Gao Peng , Zhou Tie Tao
Published: December 2012

Ceramic cores are playing a more and more important role in the modern precision casting industry system; it could influence the internal structure and performance of the castings. Especially in the precision casting field, the internal structure directly influenced the ultimate properties. This paper investigated the calcium oxide ceramic cores used in titanium precision casting fields through changing the ratio of aggregate sizes and sintering process. The main properties as bend strength, sintering shrinkage, casting reaction layer and microstructure are performed using SEM, XRD and other measurement method. Results of this research showed that the calcium oxide ceramic cores could be used in titanium precision casting, provide a stable casting property and nearly without reaction pollution to the titanium castings.
Steam Pressure of Foaming Machine of Fuzzy PID Control and Simulation
Authors: Xiong Yue Hua , Zhang Chun Liang , Fu Bai Xiang
Published: December 2012

This paper focus on designing a fuzzy PID controller design about the vapor pressure of the EPE foaming machine parameters, and raise a self-tuning method of PID parameters, and use the fuzzy control toolbox of MATLAB to simulate its control system, which are compared with the simulation of conventional PID controller, the results show the design of fuzzy PID controller have high control precision, small overshoot, good dynamic performance characteristics.
CD70 Deficiency Impairs Effector CD8 T Cell Generation and Viral Clearance but Is Dispensable for the Recall Response to Lymphocytic Choriomeningitis Virus
Authors: Munitic Ivana , Kuka Mirela , Allam Atef , Scoville Jonathan P. , Ashwell Jonathan D.
Published: December 2012

CD27 interactions with its ligand, CD70, are thought to be necessary for optimal primary and memory adaptive immune responses to a variety of pathogens. Thus far, all studies addressing the function of the CD27–CD70 axis have been performed in mice lacking CD27, in those overexpressing CD70, or in those in which these molecules were blocked or mimicked by Abs or recombinant soluble CD70. Because these methods have in some cases led to divergent results, we generated CD70-deficient mice to directly assess its role in vivo. We find that lack of CD70-mediated stimulation during primary responses to lymphocytic choriomeningitis virus lowered the magnitude of CD8 Ag-specific T cell response, resulting in impaired viral clearance, without affecting CD4 T cell responses. Unexpectedly, CD70–CD27 costimulation was not needed for memory CD8 T cell generation or the ability to mount a recall response to lymphocytic choriomeningitis virus. Adoptive transfers of wild-type memory T cells into CD70−/− or wild-type hosts also showed no need for CD70-mediated stimulation during the course of the recall response. Moreover, CD70 expression by CD8 T cells could not rescue endogenous CD70−/− cells from defective expansion, arguing against a role for CD70-mediated T:T help in this model. Therefore, CD70 appears to be an important factor in the initiation of a robust and effective primary response but dispensable for CD8 T cell memory responses.
A Double-blind Cross-over Study evaluating the Efficacy of a Light-activated Toothbrush
Authors: Uswak Gerry , Lee Jinhwa , Li Jennife
Published: December 2012

Aim

The aim of this study was to determine the efficacy of a new, light-activated toothbrush, (Soladey-J3X) incorporated with a TiO2 semiconductor and a solar panel (test) with a similar toothbrush but without the active semiconductor and solar panel (control).

Materials and methods

Forty-nine adults aged 19 to 34 years completed a double-blind, cross-over study with each participant using the test and control brush for a period of 3 weeks each. The mean differences between baseline plaque and gingivitis scores and, after the subjects used, the test and control brushes were analyzed by the paired t-test.

Results

The test and control brush demonstrated a reduction in overall plaque scores, but the difference between the two brushes was not statistically significant. The Soladey-J3X, however, showed a statistically significant difference in the overall mean reduction in gingivitis and on the buccal and interproximal surfaces compared to the control.

Conclusion

Both the test and the control toothbrushes induced a reduction in plaque scores after 3 weeks of use but the differences between the two type of brushes were not statistically significant. However, the test brush was more efficacious than the control in reducing overall gingival index scores and on the buccal and interproximal surfaces. Additional in vivo and longer term clinical trials are, however, warranted to fully investigate the mechanism and efficacy of TiO2 semiconductor toothbrushes on plaque biofilm and gingival inflammation.

How to cite this article

Uswak G, Hoover J, Lee J, Li J, Karunanayake C. A Double-blind Cross-over Study evaluating the Efficacy of a Light-activated Toothbrush. Int J Experiment Dent Sci 2012;1(2):57-60.
Association between Breastfeeding and Deleterious Oral Habits with Development of Malocclusions in Pediatric Dental Patients
Authors: Barreto Larissa Barreto , Souza Ricardo Alves , Freitas Livia Maria , Pithon Matheus Melo
Published: December 2012

Purpose

This article evaluates the inter-relationship between the feeding time, presence of deleterious oral habits and the development of malocclusion.

Materials and methods

For this purpose, a document focused on the quantitative aspects and was prepared using forms filled out according to the information available in the medical records of 93 children of both genders, aged between 4 and 12 years old, who were treated at the Dental Clinic of UESB (University of the Southwest State of Bahia), Jequié Campus, in the period from 2006 to 2009. The Chi-square statistical test was applied.

Results

We observed a higher frequency of children who were naturally breast-fed for a period longer than 6 months (47%). There was a significant relationship between the shorter duration of breastfeeding leading to deleterious oral habits, and consequently to the development of malocclusion (p < 0.001). The existence of one or more deleterious oral habits also favored the development of malocclusion, even in the group that was breast-fed for longer than 6 months (p < 0.001). The habit that appeared most frequently was onychophagy (nail biting; 26%) followed by lingual interposition (17%) and pacifier sucking (14%). The highest prevalence of crowding was found among children with malocclusion (33%).

Conclusion

Mothers should be encouraged to extend the time of breastfeeding and motivate children not to develop deleterious oral habits, as these are crucial factors in diminishing the development of malocclusion.

How to cite this article

Barreto LB, Souza RA, Freitas LM, Pithon MM. Association between Breastfeeding and Deleterious Oral Habits with Development of Malocclusions in Pediatric Dental Patients. Int J Experiment Dent Sci 2012;1(2):61-66.
Does bonding to Dentin reduce Gap formation in Composite Restorations?
Authors: Popoff Daniela Araújo Veloso , Menezes Murilo de Sousa , Gomes Andressa dos Santos , Faria-e-Silva André Luis , Soares Paulo Vinícius , Santos-Filho Paulo César , Martins Luís Roberto Marcondes
Published: December 2012

This study evaluated the effect of adhesive application only to enamel on the gap formation of composite resin restorations performed with different adhesive systems and submitted to mechanical cycling. Standardized cylinder-shaped cavities were prepared on the buccal surface of 60 bovine incisors. Two etchand-rinse [Adper Scotchbond Multi-purpose (3M ESPE, St. Paul, MN, USA) and Adper Single Bond 2 (3M ESPE)] and one selfetching [Clearfil SE Bond (Kuraray, Osaka, Japan)] adhesive systems were evaluated. The adhesives were applied only to enamel or to both dentin and enamel. After adhesive light activation, the cavities were restored with composite resin. The restorations were finished and polished; the marginal adaptation was analyzed using scanning electronic microscopy (SEM, 500× magnification) in low-vacuum mode. After the first evaluation, the samples were submitted to mechanical cycling (300,000 cycles of 80 kN and 1.5 Hz) and a new evaluation was performed. There was observed any gap for all experimental conditions before and after mechanical cycling. Bonding to dentin does not alter the marginal adaptation of composite restorations.

How to cite this article

Popoff DAV, Menezes MS, Gomes AS, Faria-e-Silva AL, Soares PV, Santos-Filho PC, Martins LRM. Does bonding to Dentin reduce Gap formation in Composite Restorations? Int J Experiment Dent Sci 2012;1(2):67-70.
Quality of Preclinical and Clinical Root Canal Fillings performed by Undergraduate Students on Single-rooted Teeth
Authors: Faria-e-Silva André Luis , Brito-Júnior Manoel , Camilo Carla Cristina , Veloso Daniela Araújo Veloso
Published: December 2012

This study evaluated the radiographic technical quality of preclinical and clinical root canal fillings (RCF) performed by undergraduate students on single-rooted teeth. Two independent calibrated endodontic specialists evaluated 94 preclinical radiographs (group 1) and 96 clinical radiographs (group 2). The apical length of each RCF was categorized as acceptable (0-2.0 mm short of the radiographic apex), underfilled (2.0 mm or more short of the radiographic apex) and overfilled (extruded beyond the radiographic apex). Inadequate or adequate homogeneity were also evaluated based on the presence of voids and the uniform density of the RCF. Cohen's kappa and Chi-square tests (p < 0.05) were used for statistical analysis. The interexaminer agreement level was almost perfect (>0.80). Approximately 80% of RCF had acceptable length in both groups, with no significant differences among them (p > 0.05). The rate of adequate homogeneity was higher in Group 2 when compared with group 1 (p < 0.05). Overall, the quality of RCF was satisfactory with better homogeneous seal at the clinical level.

How to cite this article

Brito-Júnior M, Camilo CC, Popoff DAV, Saini R, Faria-e-Silva AL. Quality of Preclinical and Clinical Root Canal Fillings performed by Undergraduate Students on Singlerooted Teeth. Int J Experiment Dent Sci 2012;1(2):71-74.
Mercury Accumulation in Fish: The Potential Effect of Dental Amalgam Wastewater
Authors: Pinheiro Tiago Novaes , Consolaro Alberto , Sakuma Alice , Buzzo Marcia Liane , Carvalho Marcia Sena de , Duran Maria Cristina
Published: December 2012

Objectives

Dental amalgam discharge in the wastewater stream is a potential source of mercury (Hg) that may contaminate the soil, water and wildlife, once released without safety measures. This study aimed the total Hg accumulation in fish Carassius auratus comparing different water environments: Water from the Tietê river basin close to the metropolitan area of Bauru, Brazil; tap water contaminated with 0.5 gm/l load of dental amalgam and tap water was used as control.

Study design

Fish were kept in glass aquaria, each water environment consisted of 25 specimens. The inner organs and muscles were sampled at 1 hour and 28 days for total Hg accumulation analysis. Also, water samples were analyzed at 1 hour, 7, 14, 21 and 28 days through cold vapor atomic absorption spectrometry.

Results

Only the fish kept at water from the Tietê river and contaminated tap water had Hg detected on its sampled tissues. The highest median levels were found in inner organs: 12.36 mg/kg–Tietê river and 262.64 mg/kg–contaminated tap water. The lowest median concentrations were found in muscles: 0.13 mg/kg–Tietê river and 0.54 mg/kg–contaminated tap water.

Conclusion

These findings alert to the potential environmental risks of dental amalgam waste discharge.

How to cite this article

Pinheiro TN, Consolaro A, Sakuma A, Buzzo ML, de Carvalho MS, Duran MC. Mercury Accumulation in Fish: The Potential Effect of Dental Amalgam Wastewater. Int J Experiment Dent Sci 2012;1(2):75-80.
Bond Strength of Resin Composites used as Core Materials around Different Types of Fiber Posts
Authors: Koçak Mustafa Murat , Cengiz Seda
Published: December 2012

The purpose of this study was to evaluate the shear bond strength of two resin composites around different types of fiber posts. Twenty post specimens were prepared for three types of fiber posts. Posts were embedded in acrylic resin blocks with half of the post diameter exposed. The exposed portions of the posts were successively ground with silicon carbide paper until flattened flush with the acrylic resin, to create a standard smooth surface. All the posts were treated with a single silane coupling agent layer. After silane application, the posts were gently air dried. Three types of fiber posts were randomly divided into two groups, according to the resin composite used. The light-cured composite resins were placed in a polytetrafluoroethylene mold positioned over the post specimens and they were polymerized. Shear bond strength values (MPa) of posts and composite resin cores were measured using an universal test machine. Twoway analysis of variance (ANOVA) and Tukey's test were used for statistical analysis. The result of two-way ANOVA showed that the difference between the post groups was not significant (p = 0.59). But significant differences were observed between the core materials (p = 0.018). The shear bond strength values were not affected by the type of the fiber post. The type of the composite core material affected the bond strength values between the fiber post and composite core.

How to cite this article

Koçak MM, Cengiz S, Koçak S. Bond Strength of Resin Composites used as Core Materials around Different Types of Fiber Posts. Int J Experiment Dent Sci 2012; 1(2):81-83.
In vitro Comparison between Two Different Implant Titanium Surfaces in Osseointegration Process
Authors: Ballini Andrea , Desiate Apollonia , Cantore Stefania
Published: December 2012

The osseointegration rate of titanium dental implants is related to their composition and surface roughness. Rough-surfaced implants favor both bone anchoring and biomechanical stability.

The future of dental implantology should aim to develop surfaces with controlled and standardized topography or chemistry.

This approach will be the only way to understand the interactions between proteins, cells and tissues and implant surfaces. The local release of bone stimulating or resorptive drugs in the peri-implant region may also respond to difficult clinical situations with poor bone quality and quantity, such as implant design and surface. These therapeutic strategies should ultimately enhance the osseointegration process of dental implants for their immediate loading and long-term success. Aim of this work was to compare implant titanium surfaces prepared with two different topographies for evaluating osteoblasts adhesion and growth.

How to cite this article

Ballini A, Desiate A, Cantore S. In vitro Comparison between Two Different Implant Titanium Surfaces in Osseointegration Process. Int J Experiment Dent Sci 2012; 1(2):84-88.
Study of Stress Distribution in Maxillary Anterior Region during True Intrusion of Maxillary Incisors using Finite Element Methodology
Authors: Vadvadgi Vinay , Bhardwaj Amit , Padmawar Sagar S , Belludi Anup
Published: December 2012

Introduction

One of the major challenges of fixed clinical orthodontics is the correction of deep overbite. Miniscrew implants are ideally suited for absolute intrusion because they make it possible to apply light continuous forces of known magnitudes without producing any reciprocal reactionary effect on posterior teeth. The purpose of this finite element method (FEM) study was to evaluate and compare the stresses generated in maxillary anterior region during absolute en masse intrusion of six maxillary teeth using mini-implants at strategic locations.

Materials and methods

Finite element model was generated using FEM software and on the same model finite element analysis was carried out to study the stress distribution in maxillary anterior region during true incisor intrusion.

Results

Soft bone and hard bone showed significantly high stress distribution in maxillary anterior region.

Conclusion

Stresses on the teeth, soft bone and hard bone, were concentrated more on and near the central incisors as compared to lateral incisors. This was probably because the point of force application was between the central incisors and away from the lateral incisors.

How to cite this article

Padmawar SS, Belludi A, Bhardwaj A, Vadvadgi V, Saini R. Study of Stress Distribution in Maxillary Anterior Region during True Intrusion of Maxillary Incisors using Finite Element Methodology. Int J Experiment Dent Sci 2012;1(2):89-92.
An Evaluation and Correlation of Leptin in Gingival Crevicular Fluid and Serum in Health, Gingivitis and Periodontitis
Authors: Vadvadgi Vinay , Padmawar Neeta
Published: December 2012

Background and objective

Plasma leptin is associated in patients with inflammatory diseases. A high concentration of leptin is associated with healthy gingival tissue. The purpose of this study was to assess the concentration of human leptin in gingival crevicular fluid (GCF) and serum within healthy and diseased gingiva, further to explore the possibility of using the levels of leptin in GCF and serum as a biochemical marker of periodontal disease progression.

Materials and methods

Ninety subjects were selected with age (30-39 years) and sex (15 males and 15 females) matched, to eliminate age and sex as confounders. The subjects were divided into three groups consisting of 30 subjects in each group based on the clinical and radiological parameters; healthy (group I), gingivitis (group II), periodontitis (group III), from whom the GCF samples were collected with Periopaper GCF collection strips (Proflow, Amityville, NY, USA) for 30 seconds and blood samples with 20-gauge needle syringe respectively. Leptin concentration was determined from individual GCF and serum samples by enzyme-linked immunosorbent assay (ELISA).

Results

The highest mean leptin concentration in GCF was observed in group I (2,664.30 pg/ml ± 324.73) and least mean leptin concentration was obtained in group III (1,309.43 pg/ml ± 202.45). The mean concentration of group II (1,639.43 pg/ml ± 344.46) was intermediate between the highest and lowest values. In contrast, the highest mean leptin concentration in serum was obtained for group III (12,086.57 pg/ml ± 1,698.23) and least mean leptin concentration was obtained for group I (8,715.09 pg/ml ± 1,649.19). The mean concentration of the group II (10,694.01 pg/ml ± 1,777.72) were intermediate between the highest and lowest values.

Conclusion

The results indicated a statistically significant decrease in the GCF leptin concentration and increase in serum leptin concentration as the periodontal disease progressed.

How to cite this article

Vadvadgi VH, Saini R, Padmawar N. An Evaluation and Correlation of Leptin in Gingival Crevicular Fluid and Serum in Health, Gingivitis and Periodontitis. Int J Experiment Dent Sci 2012;1(2):93-97.
Ectopic Meningioma in the Maxillary Alveolar Ridge: Report of a Case with a Review of the Literature
Authors: Simsek Hasan Onur , Komerik Nurgul
Published: December 2012

Aim

Meningioma is a benign intracranial tumor. Occurrence of ectopic meningioma in maxillary alveolar ridge is very rare. Our aim is to add another case of ectopic meningioma in the maxillary alveolar ridge to the literature.

Background

Meningioma is a benign tumor that originates from meningocytes found in arachnoid villous structures of the meninges. The tumor is rarely seen in extracranial locations from the oral cavity.

Case description

We report on a 51-year-old edentulous woman with an ectopic meningioma on the right maxillary alveolar ridge. The patient had complained of dull pain and discharge from the right maxillary alveolar region. On clinical examination, we observed a lobulated lesion 2 × 2 cm in size. Radiographic examination showed ill-defined radiolucency with irregular radiopaque areas. We also noted oroantral communication from the root of the lesion into to the maxillary sinus with bony destruction. We closed the oroantral communication by a buccal advancement flap. The histopathological diagnosis of the specimen was transitional type grade I meningioma. The patient's 5-year follow-up was uneventful.

Conclusion

The histological subtype of the meningioma dictates the mode of surgery. Hence, resection is not considered the treatment of choice for grade I lesions. It is important to keep in mind that meningioma is the differential diagnosis of the intraosseous mandible tumors.

Clinical Significance

Ectopic meningioma is very rare. Meningioma should be considered as a differential diagnosis in clinical lesion. In the literature review, this is the fifth case report and review of the literature.

How to cite this article

Simsek HO, Komerik N. Ectopic Meningioma in the Maxillary Alveolar Ridge: Report of a Case with a Review of the Literature. Int J Experiment Dent Sci 2012;1(2):98-101.
Primary Manifestation of Sarcoidosis Involving the Gingivae
Authors: Saylor Catherine , Beaini Nabil , Rokos James , Satheesh Keerthana , Cobb Charles
Published: December 2012

Sarcoidois of the gingiva is rarely the primary manifestation of the disease. The following case presentation highlights clinical signs and symptoms that are not uncommon or unusual except for the anatomical location of the initial expression. Appropriate treatment must be based on a definitive diagnosis which, in turn, requires a biopsy for histologic analysis.

How to cite this article

Saylor C, Beaini N, Rokos J, Satheesh K, Cobb C. Primary Manifestation of Sarcoidosis Involving the Gingivae. Int J Experiment Dent Sci 2012;1(2):102-105.
Diagnosis and Treatment of Inflammatory Root Resorption by Intentional Reimplantation
Authors: Bogra Poonam , Saini Suresh Kumar , Saini Amita
Published: December 2012

External root resorption is a lytic process occurring in the cementum or cementum and dentin of the roots of teeth. It is frequently caused by trauma. Such cases are often difficult to diagnose especially if lesion is on buccal or lingual side, and at times may be difficult to treat using conventional root canal treatment, with extraction being left the only alternative. This article describes the diagnosis and treatment of a case of inflammatory resorption of palatal wall of palatal root of maxillary left first molar by intentional reimplantation. The provisional diagnosis was made from clinical and radiographic observations. The treatment consisted of intentional reimplantation. After extraction it was found that palatal wall of palatal root had been resorbed from furcation till apex. After the resection of the palatal root at the point of resorption, tooth was obturated, reimplanted and splinted. This tooth is serving well since 5 years.

How to cite this article

Saini SK, Bogra P, Saini A. Diagnosis and Treatment of Inflammatory Root Resorption by Intentional Reimplantation. Int J Experiment Dent Sci 2012;1(2):106-109.
Unusual Presentation of Foreign Body in a Pediatric Patient
Authors: Awana Meenakshi
Published: December 2012

Missed foreign bodies are one of the leading causes of malpractice claims made against emergency physicians. Foreign bodies in the lip are not common. Here, a case of a child presenting with tooth fragment embedded in the lower lip after a fall is being reported. Accurate diagnosis was made by palpation and radiographic evaluation. The foreign body was removed surgically under local anesthesia with prompt recovery and esthetics was preserved. The patient was taken up for root canal treatment. It is essential to look for foreign bodies embedded in soft tissue particularly in children after a fall, which if overlooked can have significant complications.

How to cite this article

Talwar M, Awana M. Unusual Presentation of Foreign Body in a Pediatric Patient. Int J Experiment Dent Sci 2012;1(2):110-112.
ISW for the Treatment of Facial Asymmetry Crossbite Case with Upper Right Lateral Incisor Missing
Authors: SUN Chia-bin , YU Jian-hong
Published: December 2012

Class III malocclusion with facial asymmetry is difficult to treat with orthodontic treatment without surgery. Skeletal class III malocclusion can be treated with surgery or orthodontic treatment by camouflage. Functional class III malocclusion can be treated perfectly by orthodontic treatment, using the intermaxillary elastics (IME) to correct the jaw relation. Differentially, diagnosing a class III case is important before deciding the treatment plan. We must understand the type of class III malocclusion and then we can make the best choice for the patient. This article reports the treatment of adult class III malocclusion by the improved superelastic TiNi alloy wire (ISW). Using the ISW crossbite arch, coil springs and IME, adequate overbite and overjet were achieved and better facial symmetry was also improved.

How to cite this article

SUN Cb, YU Jh. ISW for the Treatment of Facial Asymmetry Crossbite Case with Upper Right Lateral Incisor Missing. Int J Experiment Dent Sci 2012;1(2): 113-117.

Source of support

This work was supported by China Medical University and Medical Center, Taichung City, Taiwan (Grant number: CMU97-080 (2008) to JH YU).
Chlorine Dioxide: A Potential Mouth Rinse for Oral Health
Authors: Mani Shubangi
Published: December 2012

The current global and regional patterns of oral disease largely reflect distinct risk profiles across countries, related to living conditions, lifestyles and the implementation of preventive oral health systems. Periodontitis has been proposed as having an etiological or modulating role in cardiovascular diseases, diabetes, respiratory disease, adverse pregnancy outcome and other systemic diseases. Chlorine dioxide when stabilized in water and used at low concentration effectively neutralizes volatile sulfur compounds in the oral cavity. This compound has the ability to effectively clean oral tissues on a daily basis without causing harmful side effects.

How to cite this article

Mani S, Mani A, Saini R. Chlorine Dioxide: A Potential Mouth Rinse for Oral Health. Int J Experiment Dent Sci 2012;1(2):118-119.
Adaptive Optics for Visual Simulation
Authors: Fernández Enrique Josua
Published: December 2012

A revision of the current state-of-the-art adaptive optics technology for visual sciences is provided. The human eye, as an optical system able to generate images onto the retina, exhibits optical aberrations. Those are continuously changing with time, and they are different for every subject. Adaptive optics is the technology permitting the manipulation of the aberrations, and eventually their correction. Across the different applications of adaptive optics, the current paper focuses on visual simulation. These systems are capable of manipulating the ocular aberrations and simultaneous visual testing though the modified aberrations on real eyes. Some applications of the visual simulators presented in this work are the study of the neural adaptation to the aberrations, the influence of aberrations on accommodation, and the recent development of binocular adaptive optics visual simulators allowing the study of stereopsis.
To Evaluate Serum Eosinophil Cationic Protein and Total IgE Concomitantly May Predict the Persistence of Wheezing in Young Children
Authors: Keleş Esengül , Yazgan Hamza , Gebeşçe Arzu
Published: December 2012

Background. We investigated the predictive value and the relative risk of the evaluation of serum eosinophilic cationic protein (sECP) and total IgE levels concomitantly in relation to the persistence of wheezing in young children. Methods. The study was conducted prospectively between January 2007 and December 2010. A hundred and eight children, aged between three months and four years, with three or more episodes of wheezing, were studied to evaluate the role of eosinophil inflammation and its relation to persistence of wheezing two years later. Results. A statistically significant difference in terms of total IgE and sECP values was observed between the groups (P<0.05). When measurement of IgE and sECP was assessed concomitantly, the sensitivity was found to be 92.68%, the negative predictive value was found to be 71.43%, accuracy rate was found to be 84.26%, and the relative risk was found to be 3.06 in group 1. Conclusions. In this study, we aimed to emphasize the importance of the assessment of sECP and total IgE concomitantly, as being two noninvasive and easily applicable tests, useful in predicting persistent wheezing in early childhood.
Temperature Rise during Primer, Adhesive, and Composite Resin Photopolymerization of a Low-Shrinkage Composite Resin under Caries-Like Dentin Lesions
Authors: Mousavinasab Sayed-Mostafa , Khoroushi Maryam , Moharreri Mohammadreza
Published: December 2012

Objective. This study evaluated temperature rise of low-shrinkage (LS) self-etch primer (P), LS self-etch adhesive (A), and P90 silorane-based composite resin systems, photopolymerized under normal and artificially demineralized dentin. Methods. Forty 1.5 mm-thick dentin discs were prepared from sound human molars, half of which were demineralized. Temperature rise was measured during photopolymerization using a K-type thermocouple under the discs: 10 s and 40 s irradiation of the discs (controls/groups 1 and 2); 10 s irradiation of primer (P), 10 s irradiation of adhesive (A), 40 s irradiation of P90 without P and A, and 40 s irradiation of P90 with P and A (groups 3 to 6, resp.). The samples were photopolymerized using an LED unit under 550 mW/cm2 light intensity. Data was analyzed using repeated measures ANOVA and paired-sample t-test (α=0.05). Results. There were no significant differences in temperature rise means between the two dentin samples for each irradiation duration (P>0.0001), with significant differences between the two irradiation durations (P>0.0001). Temperature rise measured with 40 s irradiation was significantly higher than that of 10 s duration for undemineralized and demineralized dentin P<0.0001). Conclusions. Light polymerization of P90 low-shrinkage composite resin resulted in temperature rise approaching threshold value under artificially demineralized and undemineralized dentin.
Powers of Commutators and Anticommutators
Authors: Buckley Stephen M. , MacHale Desmond
Published: December 2012

For , we give elementary proofs of commutativity of rings in which the identity holds for all commutators . For even , we show that the commutativity of rings satisfying such an identity is equivalent to the anticommutativity of rings satisfying the corresponding anticommutator equation.
Pore Size Distribution Analysis of Coal-Based Activated Carbons: Investigating the Effects of Activating Agent and Chemical Ratio
Authors: Okhovat Ahmad , Ahmadpour Ali , Ahmadpour Farzaneh , Khaki Yadegar Zahra
Published: December 2012

The present study attempts to investigate the effects of different chemical agents and chemical ratios on pore structure of coal-based activated carbons. The adsorption isotherm data of two series of activated carbons prepared from bituminous coal by chemical activation with potassium hydroxide and zinc chloride were used. Four well-known models of Dubinin-Stoeckli, Stoeckli, Horvath-Kawazoe, and improved Horvath-Kawazoe were applied for the characterization of these porous solids. Although the results showed some differences among the models that arise from their fundamental assumptions, in general they are found to be comparable. Results showed that samples activated by ZnCl2 provide higher-adsorption capacity than those from KOH. In each series, it was shown that the pore volume increases with increasing impregnation ratio, ranging from 50% to 200%. Activated carbons obtained at low chemical ratio in ZnCl2 series (up to 100%) showed microporous structure, while those with higher ratios became predominantly mesoporous. In the KOH series, increasing KOH created more micropores in the carbon structure in the whole range of studied chemical ratio.
Fast-Track Surgery in Gynaecology and Gynaecologic Oncology: A Review of a Rolling Clinical Audit
Authors: Carter Jonathan
Published: December 2012

Clinical audit is the process by which clinicians are able to demonstrate to themselves, their patients, hospital administrators, and healthcare financial providers the outcome and safety of their clinical practice. It is a process by which the public can be assured of safety and outcomes. A fast-track surgery program was initiated in January 2008, and this paper represents a rolling clinical audit of the outcomes of that program until the end of June 2012. Three hundred and eighty-nine patients underwent fast track surgical management after having a laparotomy for suspected or confirmed gynaecological cancer. There were no exclusions and the data presented represents the practice and outcomes of all patients referred to a single gynaecological oncologist. The majority of patients were deemed to have complex surgical procedures performed usually through a vertical midline incision. One third of patients had a nonzero performance status, median weight was 68 kilograms, and median BMI was 26.5 with 31% being classified as obese. Median operating time was 2.25 hours, and the median estimated blood loss was 175 mL. Overall the median length of stay (LOS) was 3 days with 95% of patients tolerating early oral feeding. Four percent of patients required readmission, and 0.5% were required to return to the operating room. Whilst the wound infection rate was 2.6%, there were no ureteric, bowel or neurovascular injuries. Overall there were 2 bladder injuries (0.5%), and the incidence of venous thromboembolism was 1%. Subset analysis was also undertaken. Whilst a number of variables were associated with reduced LOS, on multivariate analysis, benign pathology, shorter operating time, and the ability to tolerate early oral feeding were found to be significant. The data and experience presented is the largest and most extensive reported in the literature relating to fast-track surgery in gynaecology and gynaecologic oncology. The public can be reassured of the safety and improved outcomes that can be achieved after the introduction of such a program.