Search results for: Dental composites
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1341

Search results for: Dental composites

1311 Changes in the Properties of Composites Caused by Chemical Treatment of Hemp Hurds

Authors: N. Stevulova, I. Schwarzova

Abstract:

The possibility of using industrial hemp as a source of natural fibers for purpose of construction, mainly for the preparation of lightweight composites based on hemp hurds is described. In this article, an overview of measurement results of important technical parameters (compressive strength, density, thermal conductivity) of composites based on organic filler - chemically modified hemp hurds in three solutions (EDTA, NaOH and Ca(OH)2) and inorganic binder MgO-cement after 7, 28, 60, 90 and 180 days of hardening is given. The results of long-term water storage of 28 days hardened composites at room temperature were investigated. Changes in the properties of composites caused by chemical treatment of hemp material are discussed.

Keywords: hemp hurds, chemical modification, lightweight composites, testing material properties

Procedia PDF Downloads 349
1310 Assessment of Dental Caries in Children of Age 6 and 7 Years Old in Albania

Authors: Mimoza Canga, Irene Malagnino, Ruzhdie Qafmolla, Vergjini Mulo, Gresa Baboci, Vito Antonio Malagnino

Abstract:

Background: Dental caries represents the most widespread pathology in childhood. The prevalence of dental caries varies with age, gender, socio economic status, geographical location, nutrition habits, and oral hygiene. Objective: The objective of the present longitudinal study is to show clearly the prevalence of dental caries in the children of age 6 and 7 years old in Vlore, Albania, in a two year time period with controls done every 6 months. Materials and methods: The present study was conducted on 530 children, with a controlled sample for a time period of 24 months from September 2019- September 2021. The children in the study had different economic and social backgrounds. The teeth controls were done by the dentists who work at the hospital of the city. The present study was conducted in accordance with Helsinki declaration. Permissions were obtained in written form, which allowed us to perform the observations. Parents had the right to withdraw their children at any time. Statistical analysis was performed using IBM SPSS Statistics 23.0. The significance level (α) was set at 0.05, whereas P-value and analysis of variance (ANOVA) were used to analyze the data. Results: The data of the present study showed that the age group of 6 years old had 139 or 52.3% of the children with dental caries and 127 or 47.7% of them had no dental caries, while at the age of 7 there were 184 or 69.7% of the children with dental caries problems in the permanent molars and 80 or 30.3% of them had no dental caries. In the present study, it was observed that there is a statistically significant association between age group and presence of caries. Children 7 years old had higher presence of dental caries (χ2 = 16.934 (df 1) p-value < 0.001). According to the present research, there is a statistically significant correlation between period of time and the presence of dental caries. Furthermore, in the actual research, it was established that in the time 18-24 months, the prevalence of dental caries was high (χ2=15,318 (df 1) p-value = 0.004). Conclusion: According to the results of the present study performed in Albania in a two year time period with controls done every 6 months, it is proved that the prevalence of dental caries was 17.4 percent higher among children 7 years old in comparison with the children 6 years old.

Keywords: age, children, dental caries, permanent molars

Procedia PDF Downloads 225
1309 Evaluation of the Sterilization Practice in Liberal Dental Surgeons at Sidi Bel Abbes- Algeria

Authors: A. Chenafa, S. Boulenouar, M. Zitouni, M. Boukouria

Abstract:

The sterilization of medical devices constitutes for all the medical professions, an inescapable obligation. It has for objective to prevent the infectious risk, both for the patient and for the medical team. The Dental surgeon as every healthcare professional has to master perfectly this subject and to train his staff to the various techniques of sterilization. It is the only way to assure the patients all the security for which they are entitled to wait when they undergo a dental care. It’s for it, that we undertook to lead an investigation aiming at estimating the sterilization practice at the dental surgeon of Sidi bel Abbes. The survey result showed a youth marked with the profession with a majority use of autoclave with cycle B and an almost total absence of the sterilization controls (test of Bowie and Dick). However, the majority of the dentists control and validate their sterilizers. Finally, our survey allowed us to describe some practices which must be improved regarding control, regarding qualification and regarding staff training. And suggestions were made in this sense.

Keywords: dental surgeon, medical devices, sterilization, survey

Procedia PDF Downloads 402
1308 A Review on Aluminium Metal Matric Composites

Authors: V. Singh, S. Singh, S. S. Garewal

Abstract:

Metal matrix composites with aluminum as the matrix material have been heralded as the next great development in advanced engineering materials. Aluminum metal matrix composites (AMMC) refer to the class of light weight high performance material systems. Properties of AMMCs can be tailored to the demands of different industrial applications by suitable combinations of matrix, reinforcement and processing route. AMMC finds its application in automotive, aerospace, defense, sports and structural areas. This paper presents an overview of AMMC material systems on aspects relating to processing, types and applications with case studies.

Keywords: aluminum metal matrix composites, applications of aluminum metal matrix composites, lighting material processing of aluminum metal matrix composites

Procedia PDF Downloads 465
1307 A Comparative Study of Microstructure, Thermal and Mechanical Properties of A359 Composites Reinforced with SiC, Si3N4 and AlN Particles

Authors: Essam Shalaby, Alexander Churyumov, Malak Abou El-Khair, Atef Daoud

Abstract:

A comparative study of the thermal and mechanical behavior of squeezed A359 composites containing 5, 10 and 15 wt.% SiC, (SiC+ Si3N4) and AlN particulates was investigated. Stir followed by squeeze casting techniques are used to produce A359 composites. It was noticed that, A359/AlN composites have high thermal conductivity as compared to A359 alloy and even to A359/SiC or A359/(SiC+Si3N4) composites. Microstructures of the composites have shown homogeneous and even distribution of reinforcements within the matrix. Interfacial reactions between particles and matrix were investigated using X-ray diffraction and energy dispersive X-ray analysis. The presence of particles led not only to increase peak hardness of the composites but also to accelerate the aging kinetics. As compared with A359 matrix alloy, compression test of the composites has exhibited a significant increase in the yield and the ultimate compressive strengths with a relative reduction in the failure strain. Those light weight composites have a high potential to be used for automotive and aerospace applications.

Keywords: metal-matrix composite, squeeze, microstructure, thermal conductivity, compressive properties

Procedia PDF Downloads 382
1306 Comparative Study to Evaluate Chronological Age and Dental Age in North Indian Population Using Cameriere Method

Authors: Ranjitkumar Patil

Abstract:

Age estimation has its importance in forensic dentistry. Dental age estimation has emerged as an alternative to skeletal age determination. The methods based on stages of tooth formation, as appreciated on radiographs, seems to be more appropriate in the assessment of age than those based on skeletal development. The study was done to evaluate dental age in north Indian population using Cameriere’s method. Aims/Objectives: The study was conducted to assess the dental age of North Indian children using Cameriere’smethodand to compare the chronological age and dental age for validation of the Cameriere’smethod in the north Indian population. A comparative study of 02 year duration on the OPG (using PLANMECA Promax 3D) data of 497 individuals with age ranging from 5 to 15 years was done based on simple random technique ethical approval obtained from the institutional ethical committee. The data was obtained based on inclusion and exclusion criteria was analyzed by a software for dental age estimation. Statistical analysis: Student’s t test was used to compare the morphological variables of males with those of females and to compare observed age with estimated age. Regression formula was also calculated. Results: Present study was a comparative study of 497 subjects with a distribution between male and female, with their dental age assessed by using Panoramic radiograph, following the method described by Cameriere, which is widely accepted. Statistical analysis in our study indicated that gender does not have a significant influence on age estimation. (R2= 0.787). Conclusion: This infers that cameriere’s method can be effectively applied in north Indianpopulation.

Keywords: Forensic, Chronological Age, Dental Age, Skeletal Age

Procedia PDF Downloads 90
1305 Wear Damage of Glass Fiber Reinforced Polyimide Composites with the Addition of Graphite

Authors: Mahmoudi Noureddine

Abstract:

The glass fiber (GF) reinforced polyimide (PL) composites filled with graphite powders were fabricated by means of hot press molding technique. The friction and wear properties of the resulting composites sliding against GCr15 steel were investigated on a model ring-on-block test rig at dry sliding condition. The wear mechanisms were also discussed, based on scanning electron microscopic examination of the worn surface of the PL composites and the transfer film formed on the counterpart. With the increasing normal loads, the friction coefficient of the composites increased under the dry sliding, owing to inconsistent influences of shear strength and real contact areas. Experimental results revealed that the incorporation of graphite significantly improve the wear resistance of the glass fibers reinforced polyimide composites. For best combination of friction coefficient and wear rate, the optimal volume content of graphite in the composites appears to be 45 %. It was also found that the tribological properties of the glass fiber reinforced PL composites filled with graphite powders were closely related with the sliding condition such as sliding rate and applied load.

Keywords: composites, fiber, friction, wear

Procedia PDF Downloads 356
1304 Plaque Removal Efficacy of Different Dental Care Products during Fixed Orthodontic Appliance Therapy

Authors: Zeynep Karakoc, Hasan Ilhan Mutaf

Abstract:

Plaque removal efficacy of different dental brushes and mouth wash during fixed orthodontic appliance therapy was evaluated in this single-blind, crossover and prospective study. Thirty orthodontic patients aged 18 and over undergoing fixed appliance therapy at the end of leveling stage were divided into three groups. Subjects brushed their teeth with a toothbrush under standardized conditions for a period of 30 days prior to inter-dental care products. The same procedure was repeated each time with a different, randomly assigned inter-dental care products in a crossover design. (Inter-dental brush, powered inter-dental brush and mouth wash). At start and end of each removal period, plaque indexes of participants were scored. Each brush achieved statistically significant plaque removal; however, there were no statistical differences among groups for all surfaces of teeth when the plaque score was evaluated. The mouth wash group presented significant improvement in reduction of visible plaque on mesial and distal surfaces of posterior teeth. (-60.9 %, P< .001) Plaque removal for right and left side of mouth showed no significant differences within groups, only mouth wash was more efficient in right side than left side. It is concluded that effectiveness of plaque removal may not be related to the kind of inter-dental products directly. However, toothbrush when used with inter-dental care products is significantly better at removing plaque deposits from fixed appliance patients.

Keywords: orthodontics, dental care, brush, plaque

Procedia PDF Downloads 243
1303 A Comparative Study to Evaluate Chronological Age and Dental Age in the North Indian Population Using Cameriere's Method

Authors: Ranjitkumar Patil

Abstract:

Age estimation has importance in forensic dentistry. Dental age estimation has emerged as an alternative to skeletal age determination. The methods based on stages of tooth formation, as appreciated on radiographs, seem to be more appropriate in the assessment of age than those based on skeletal development. The study was done to evaluate dental age in the north Indian population using Cameriere’s method. Aims/Objectives: The study was conducted to assess the dental age of North Indian children using Cameriere’s method and to compare the chronological age and dental age for validation of the Cameriere’s method in the north Indian population. A comparative study of 02-year duration on the OPG (using PLANMECA Promax 3D) data of 497 individuals with ages ranging from 5 to 15 years was done based on simple random technique ethical approval obtained from institutional ethical committee. The data was obtained based on inclusion and exclusion criteria and was analyzed by software for dental age estimation. Statistical analysis: The student’s t-test was used to compare the morphological variables of males with those of females and to compare observed age with estimated age. The regression formula was also calculated. Results: Present study was a comparative study of 497 subjects with a distribution between males and females, with their dental age assessed by using a Panoramic radiograph, following the method described by Cameriere, which is widely accepted. Statistical analysis in our study indicated that gender does not have a significant influence on age estimation. (R2= 0.787). Conclusion: This infers that Cameriere’s method can be effectively applied to the north Indian population.

Keywords: forensic, dental age, skeletal age, chronological age, Cameriere’s method

Procedia PDF Downloads 116
1302 Study of Biocomposites Based of Poly(Lactic Acid) and Olive Husk Flour

Authors: Samra Isadounene, Amar Boukerrou, Dalila Hammiche

Abstract:

In this work, the composites were prepared with poly(lactic acid) (PLA) and olive husk flour (OHF) with different percentages (10, 20 and 30%) using extrusion method followed by injection molding. The morphological, mechanical properties and thermal behavior of composites were investigated. Tensile strength and elongation at break of composites showed a decreasing trend with increasing fiber content. On the other hand, Young modulus and storage modulus were increased. The addition of OHF resulted in a decrease in thermal stability of composites. The presence of OHF led to an increase in percentage of crystallinity (Xc) of PLA matrix.

Keywords: biopolymers, composites, mechanical properties, poly(lactic acid)

Procedia PDF Downloads 239
1301 Biological Applications of CNT Inherited Polyaniline Nano-Composites

Authors: Yashfeen Khan, Anees Ahmad

Abstract:

In the last few decades, nano-composites have been the topic of interest. Presently, the modern era enlightens the synthesis of hybrid nano-composites over their individual counterparts because of higher application potentials and synergism. Recently, CNT hybrids have demonstrated their pronounced capability as effective sorbents for the removal of heavy metal ions (the root trouble) and organic contaminants due to their high specific surface area, enhanced reactivity, and sequestration characteristics. The present abstract discusses removal efficiencies of organic, inorganic pollutants through CNT/PANI/ composites. It also represents the widespread applications of CNT like monitoring biological systems, biosensors, as heat resources for treating cancer, fire retardant applications of polymer/CNT composites etc. And considering the same, this article aims to brief the scenario of CNT-PANI nano-composites.

Keywords: biosensors, CNT, hybrids, polyaniline, synergism

Procedia PDF Downloads 377
1300 Study of the ZnO Effect on the Properties of HDPE/ ZnO Nanocomposites

Authors: F. Z. Benabid, F. Zouai, N. Kharchi, D. Benachour

Abstract:

A HDPE/ZnO nano composites have been successfully performed using the co-mixing. The ZnO was first co-mixed with the stearic acid then added to the polymer in the plastograph. The nano composites prepared with the co-mixed ZnO were compared to those prepared with the neat TiO2. The nano composites were characterized by different techniques as the wide-angle X-ray scattering (WAXS). The micro and nano structure/properties relationships were investigated. The present study allowed establishing good correlations between the different measured properties.

Keywords: exfoliation, ZnO, nano composites, HDPE, co-mixing

Procedia PDF Downloads 353
1299 Study on the Mechanical Properties of Bamboo Fiber-Reinforced Polypropylene Based Composites: Effect of Gamma Radiation

Authors: Kamrun N. Keya, Nasrin A. Kona, Ruhul A. Khan

Abstract:

Bamboo fiber (BF) reinforced polypropylene (PP) based composites were fabricated by a conventional compression molding technique. In this investigation, bamboo composites were manufactured using different percentages of fiber, which were varying from 25-65% on the total weight of the composites. To fabricate the BF/PP composites untreated and treated fibers were selected. A systematic study was done to observe the physical, mechanical, and interfacial behavior of the composites. In this study, mechanical properties of the composites such as tensile, impact, and bending properties were observed precisely. Maximum tensile strength (TS) and bending strength (BS) were found for 50 wt% fiber composites, 65 MPa, and 85.5 MPa respectively, whereas the highest tensile modulus (TM) and bending modulus (BM) was examined, 5.73 GPa and 7.85 GPa respectively. The BF/PP based composites were treated with irradiated under gamma radiation (the source strength 50 kCi Cobalt-60) of various doses (i.e. 10, 20, 30, 40, 50 and 60 kGy doses). The effect of gamma radiation on the composites was also investigated, and it found that the effect of 30.0 kGy (i.e. units for radiation measurement is 'gray', kGy=kilogray) gamma dose showed better mechanical properties than other doses. After flexural testing, fracture sides of the untreated and treated both composites were studied by scanning electron microscope (SEM). SEM results of the treated BF/PP based composites showed better fiber-matrix adhesion and interfacial bonding than untreated BF/PP based composites. Water uptake and soil degradation tests of untreated and treated composites were also investigated.

Keywords: bamboo fiber, polypropylene, compression molding technique, gamma radiation, mechanical properties, scanning electron microscope

Procedia PDF Downloads 134
1298 Role of Nano Gelatin and Hydrogel Based Scaffolds in Odontogenic Differentiation of Human Dental Pulp Stem Cells

Authors: Husain S. Yawer, Vasim Raja Panwar, Nidhi Priya

Abstract:

The objective of this study is to evaluate and compare the role of nano-gelatin and Bioengineered Scaffolds on the attachment, proliferation, and osteogenic differentiation of human dental pulp stem cells (DPSCs). Tooth decay and early fall have each been one of the most prevailing dental disorders which cause physical and emotional suffering and compromise the patient's quality of life. The design of novel scaffolding materials will be based on mimicking the architecture of natural dental extracellular matrix which may provide as in vivo environments for proper cell growth. This methodology will involve the combination of nano-fibred gelatin as well as biodegradable hydrogel based tooth scaffold. We have measured and optimized the Dental Pulp Stem Cells growth profile in cultures carried out on collagen-coated plastic surface, however, for tissue regeneration study, we aim to develop an enhanced microenvironment for stem cell growth and dental tissue regeneration. We believe biomimetic cell adhesion and scaffolds might provide a near in vivo growth environment for proper growth and differentiation of human DPSCs, which further help in dentin/pulp tissue regeneration.

Keywords: nano-gelatin, stem cells, dental pulp, scaffold

Procedia PDF Downloads 330
1297 Fatigue of Multiscale Nanoreinforced Composites: 3D Modelling

Authors: Leon Mishnaevsky Jr., Gaoming Dai

Abstract:

3D numerical simulations of fatigue damage of multiscale fiber reinforced polymer composites with secondary nanoclay reinforcement are carried out. Macro-micro FE models of the multiscale composites are generated automatically using Python based software. The effect of the nanoclay reinforcement (localized in the fiber/matrix interface (fiber sizing) and distributed throughout the matrix) on the crack path, damage mechanisms and fatigue behavior is investigated in numerical experiments.

Keywords: computational mechanics, fatigue, nanocomposites, composites

Procedia PDF Downloads 607
1296 Dental Education in Brazil: A Systematic Literature Review

Authors: Fabiane Alves Farias Guimarães, Rodrigo Otávio Moretti-Pires, Ana Lúcia Schaefer Ferreira de Mello

Abstract:

Introduction: Considering the last changes in Brazilian Health and Higher Educational Systems, the production of scientific knowledge regarding dental education and training has been increasing. The National Curriculum Guidelines for undergraduate courses in Dentistry established in 2002 the principles and procedures to perform a more generalist dental professional profile. Objectives: To perform a systematic review of the Brazilian scientific literature about dental education and training. Methods: The systematic review was conducted considering the Lilacs - Latin American Literature in Health Sciences and SciELO - Scientific Electronic Library Online data bases, using the combination of key words dentistry, education, teaching or training. It was select original research articles, published between 2010 and 2013, in Portuguese. Results: Based on the selection criteria, it was found 23 articles. In order to organize the outcomes, the analysis was separated in three themes: Ethical aspects of education (3 articles), integrating dental service with training (10 articles) and Dental education and the Brazilian curriculum guidelines (10 articles). Most of the studies were published between 2011 and 2012 (35% each) and were held in public universities. The studied populations included dental students, teachers, universities directors, health managers and dentists. The qualitative methodological approach was predominant. Conclusion: It was possible to identify a transience time in Brazilian undergraduate courses in Dentistry after curricular changes. The produced literature shows some advances, as the incorporation of ethical values on dental education and the inclusion of new practices environments for students by integrating education and training in diversified dental services scenarios.

Keywords: Teaching, Dental Students, Human resources in dentistry

Procedia PDF Downloads 534
1295 Dielectric Properties of PANI/h-BN Composites

Authors: Seyfullah Madakbas, Emrah Cakmakci

Abstract:

Polyaniline (PANI), the most studied member of the conductive polymers, has a wide range of uses from several electronic devices to various conductive high-technology applications. Boron nitride (BN) is a boron and nitrogen containing compound with superior chemical and thermal resistance and thermal conductivity. Even though several composites of PANI was prepared in literature, the preparation of h-BN/PANI composites is rare. In this work PANI was polymerized in the presence of different amounts of h-BN (1, 3 and 5% with respect to PANI) by using 0.1 M solution of NH4S2O8 in HCl as the oxidizing agent and conductive composites were prepared. Composites were structurally characterized with FTIR spectroscopy and X-Ray Diffraction (XRD). Thermal properties of conductive composites were determined by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Dielectric measurements were performed in the frequency range of 106–108 Hz at room temperature. The corresponding bands for the benzenoid and quinoid rings at around 1593 and 1496 cm-1 in the FTIR spectra of the composites proved the formation of polyaniline. Together with the FTIR spectra, XRD analysis also revealed the existence of the interactions between PANI and h-BN. Glass transition temperatures (Tg) of the composites increased with the increasing amount of PANI (from 87 to 101). TGA revealed that the char yield of the composites increased as the amount of h-BN was increased in the composites. Finally the dielectric permittivity of 3 wt.%h-BN-containing composite was measured and found as approximately 17. This work was supported by Marmara University, Commission of Scientific Research Project.

Keywords: dielectric permittivity, h-BN, PANI, thermal analysis

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1294 Dielectric Properties of MWCNT-Muscovite/Epoxy Hybrid Composites

Authors: Nur Suraya Anis Ahmad Bakhtiar, Hazizan Md Akil

Abstract:

In the present work, the dielectric properties of Epoxy/MWCNTs-muscovite HYBRID and MIXED composites based on ratio 30:70 were studies. The multi-wall carbon nanotubes (MWCNTs) were prepared by two method; (a) muscovite-MWCNTs hybrids were synthesized by chemical vapor deposition (CVD) and (b) physically mixing of muscovite with MWCNTs. The effect of different preparations of the composites and filler loading was evaluated. It is revealed that the dielectric constants of HYBRID epoxy composites are slightly higher compared to MIXED epoxy composites. It is also indicated that the dielectric constant increased by increases the MWCNTs filler loading.

Keywords: muscovite, epoxy, dielectric properties, hybrid composite

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1293 An Antibacterial Dental Restorative Containing 3,4-Dichlorocrotonolactone: Synthesis, Formulation and Evaluation

Authors: Dong Xie, Leah Howard, Yiming Weng

Abstract:

The objective of this study was to synthesize and characterize 5-acryloyloxy-3,4-dichlorocrotonolactone (a furanone derivative), use this derivative to modify a dental restorative, and study the effect of the derivative on the antibacterial activity and compressive strength of the formed restorative. In this study, a furanone derivative was synthesized, characterized, and used to formulate a dental restorative. Compressive strength (CS) and S. mutans viability were used to evaluate the mechanical strength and antibacterial activity of the formed restorative. The fabricated restorative specimens were photocured and conditioned in distilled water at 37oC for 24 h, followed by direct testing for CS or/and incubating with S. mutans for 48 h for antibacterial testing. The results show that the modified dental restorative showed a significant antibacterial activity without substantially decreasing the mechanical strengths. With addition of the antibacterial derivative up to 30%, the restorative kept its original CS nearly unchanged but showed a significant antibacterial activity with 68% reduction in the S. mutans viability. Furthermore, the antibacterial function of the modified restorative was not affected by human saliva. The aging study also indicates that the modified restorative may have a long-lasting antibacterial function. It is concluded that this experimental antibacterial restorative may potentially be developed into a clinically attractive dental filling restorative due to its high mechanical strength and antibacterial function.

Keywords: antibacterial, dental restorative, compressive strength, S. mutans viability

Procedia PDF Downloads 326
1292 Two-Phase Flow Study of Airborne Transmission Control in Dental Practices

Authors: Mojtaba Zabihi, Stephen Munro, Jonathan Little, Ri Li, Joshua Brinkerhoff, Sina Kheirkhah

Abstract:

Occupational Safety and Health Administration (OSHA) identified dental workers at the highest risk of contracting COVID-19. This is because aerosol-generating procedures (AGP) during dental practices generate aerosols ( < 5µm) and droplets. These particles travel at varying speeds, in varying directions, and for varying durations. If these particles bear infectious viruses, their spreading causes airborne transmission of the virus in the dental room, exposing dentists, hygienists, dental assistants, and even other dental clinic clients to the infection risk. Computational fluid dynamics (CFD) simulation of two-phase flows based on a discrete phase model (DPM) is carried out to study the spreading of aerosol and droplets in a dental room. The simulation includes momentum, heat, and mass transfers between the particles and the airflow. Two simulations are conducted and compared. One simulation focuses on the effects of room ventilation in winter and summer on the particles' travel. The other simulation focuses on the control of aerosol and droplets' spreading. A suction collector is added near the source of aerosol and droplets, creating a flow sink in order to remove the particles. The effects of the suction flow on the aerosol and droplet travel are studied. The suction flow can remove aerosols and also reduce the spreading of droplets.

Keywords: aerosols, computational fluid dynamics, COVID-19, dental, discrete phase model, droplets, two-phase flow

Procedia PDF Downloads 266
1291 Study on the Fabrication and Mechanical Characterization of Pineapple Fiber-Reinforced Unsaturated Polyester Resin Based Composites: Effect of Gamma Irradiation

Authors: Kamrun N. Keya, Nasrin A. Kona, Ruhul A. Khan

Abstract:

Pineapple leaf fiber (PALF) reinforced polypropylene (PP) based composites were fabricated by a conventional compression molding technique. In this investigation, PALF composites were manufactured using different percentages of fiber, which were varying from 25-50% on the total weight of the composites. To fabricate the PALF/PP composites, untreated and treated fibers were selected. A systematic study was done to observe the physical, mechanical and interfacial behavior of the composites. In this study, mechanical properties of the composites such as tensile, impact and bending properties were observed precisely. It was found that 45wt% of fiber composites showed better mechanical properties than others. Maximum tensile strength (TS) and bending strength (BS) was observed, 65 MPa and 50 MPa respectively, whereas the highest tensile modulus (TM) and bending modulus (BM) was examined, 1.7 GPa and 0.85 GPa respectively. The PALF/PP based composites were treated with irradiated under gamma radiation (the source strength 50 kCi Cobalt-60) of various doses (2.5 kGy to 10 kGy). The effect of gamma radiation on the composites was also investigated, and it found that the effect of 5.0 kGy (i.e. units for radiation measurement is 'gray', kGy=kilogray ) gamma dose showed better mechanical properties than other doses. The values of TS, BS, TM, and BM of the irradiated (5.0 kGy) composites were found to improve by 19%, 23%, 17% and 25 % over non-irradiated composites. After flexural testing, fracture sides of the untreated and treated both composites were studied by scanning electron microscope (SEM). SEM results of the treated PALF/PP based composites showed better fiber-matrix adhesion and interfacial bonding than untreated PALF/PP based composites. Water uptake and soil degradation tests of untreated and treated composites were also investigated.

Keywords: PALF, polypropylene, compression molding technique, gamma radiation, mechanical properties, scanning electron microscope

Procedia PDF Downloads 151
1290 Polypropylene/Red Mud Polymer Composites: Effects of Powder Size on Mechanical and Thermal Properties

Authors: Munir Tasdemir

Abstract:

Polymer/clay composites have received great attention in the past three decades owing to their light weight coupled with significantly better mechanical and barrier properties than the corresponding neat polymer resins. An investigation was carried out on the effects of red mud powder size and ratio on the mechanical and thermal properties of polypropylene /red mud polymer composites. Red mud, in four different concentrations (0, 10, 20 and 30 wt %) and three different powder size (180, 63 and 38 micron) were added to PP to produce composites. The mechanical properties, including the elasticity modulus, tensile & yield strength, % elongation, hardness, Izod impact strength and the thermal properties including the melt flow index, heat deflection temperature and vicat softening point of the composites were investigated. The structures of the composites were investigated by scanning electron microscopy and compared to mechanical and thermal properties as a function of red mud powder content and size.

Keywords: polypropylene, powder, red mud, mechanical properties

Procedia PDF Downloads 338
1289 Pediatric Emergency Dental Visits at King Abdulaziz University Dental Hospital during the COVID-19 Lockdown: A Retrospective Study

Authors: Sara Alhabli, Eman Elashiry, Osama Felemban, Abdullah Almushayt, Faisal Dardeer, Ahmed Mohammad, Fajr Orri, Nada Bamashmous

Abstract:

Background: In December of 2019, the coronavirus (SARS-CoV-2) first appeared and quickly spread to become a worldwide pandemic. This study aimed to evaluate the prevalence and types of pediatric dental emergencies during the COVID-19 lockdown in Jeddah, Saudi Arabia, at the University Dental Hospital (UDH) of King Abdulaziz University (KAU) and identified the management provided for these dental emergency visits. Materials and Methods: Data collection was done retrospectively from electronic dental records for children aged 0-18 that attended the UDH emergency clinic during the period from March 1st, 2020, to September 30th, 2020. An electronic form formulated specifically for this study was used to collect the required data from electronic patient records, including demographic data, emergency classification, management, and referrals. Results: A total of 3146 patients were seen at the emergency clinics during this period, of which 661 were children (21%). Types of emergency conditions included 0.8% emergency cases, 34% urgent, and 65.2% non-urgent conditions. Severe dental pain (73.1%) and abscesses (20%) were the most common urgent dental conditions. Most non-urgent conditions presented for initial or periodic visits, recalls, or routine radiographs (74%). Treatments rarely involved restorations, with 8% among urgent conditions and 5.4% among non-urgent conditions. Antibiotics were only prescribed to 6.9% of urgent conditions. Conclusions: The largest group of children presenting at the emergency dental clinics were found to be children with non-urgent conditions. Tele dentistry can be a solution to avoid large numbers of non-urgent patients presenting to emergency clinics. Additionally, dental care for non-urgent conditions during the pandemic should focus more on procedures with less aerosol generation.

Keywords: COVID-19 pandemic, dental emergencies, oral health, pediatric dentistry, children

Procedia PDF Downloads 98
1288 Innovative Approaches in Dental Implantology: Enhancing Osseointegration and Patient Outcomes

Authors: Apameh Moslem Gheshlaghi

Abstract:

This research explores advancements in dental implantology with a focus on improving osseointegration and long-term patient outcomes. It highlights cutting-edge materials, surface modifications, and minimally invasive surgical techniques. The study also evaluates the role of digital dentistry and 3D printing in revolutionizing implant design and placement. Findings demonstrate significant improvements in patient satisfaction, procedural efficiency, and overall success rates, paving the way for more predictable and sustainable practices in modern dentistry.

Keywords: dental implants, osseointegration, digital dentistry, 3D printing

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1287 Review on Wear Behavior of Magnesium Matrix Composites

Authors: Amandeep Singh, Niraj Bala

Abstract:

In the last decades, light-weight materials such as magnesium matrix composites have become hot topic for material research due to their excellent mechanical and physical properties. However, relatively very less work has been done related to the wear behavior of these composites. Magnesium matrix composites have wide applications in automobile and aerospace sector. In this review, attempt has been done to collect the literature related to wear behavior of magnesium matrix composites fabricated through various processing techniques such as stir casting, powder metallurgy, friction stir processing etc. Effect of different reinforcements, reinforcement content, reinforcement size, wear load, sliding speed and time have been studied by different researchers in detail. Wear mechanism under different experimental condition has been reviewed in detail. The wear resistance of magnesium and its alloys can be enhanced with the addition of different reinforcements. Wear resistance can further be enhanced by increasing the percentage of added reinforcements. Increase in applied load during wear test leads to increase in wear rate of magnesium composites.

Keywords: hardness, magnesium matrix composites, reinforcement, wear

Procedia PDF Downloads 334
1286 Examining the Level of Anxiety and Stress in Dental Students

Authors: Vusale Aliyev, Khalil Aryanfar

Abstract:

Background and purpose: Dentistry is a stressful profession, and dental students are exposed to educational and clinical stress. The present study was conducted to investigate the level of stress and its factors in dental students of Nakhjavan University of Medical Sciences in 2023. Methodology: This was a descriptive cross-sectional study conducted on dental students in Nakhjavan. The data collection tool was the standard DASS-21 questionnaire (Depression-anxiety-stress scale-21) and the demographic information questionnaire. After collecting the data in SPSS statistical software, using Linear regression analysis, test regression and t-tests were subjected to statistical analysis. Results: 32.6% of students had moderate stress, and 4.3% had severe stress, and no significant statistical difference was observed between the two genders living; there was a significant difference with others (P=0.047). There was no significant relationship between the stress factor and the academic year (P=0.037). 66% of people were related to university issues. Conclusion: According to the results of this research, the level of stress is relatively high, and it seems necessary to pay attention to this issue.

Keywords: stress, dental students, Nakhichevan State University, anxiety

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1285 Prevalence of Tobacco Use and Practice among Patients Attending Dental Institution: A Cross-Sectional Study

Authors: Vinay Gupta, Seema Malhotra

Abstract:

Background: Patients who usually consume tobacco are unaware of its ill effects completely therefore it becomes necessary to educate and counselling them after obtaining their knowledge about tobacco. Aim: To measure prevalence of tobacco use among dental outpatients and to evaluation of tobacco user attending dental outpatients (OPD) prepared to quit. Methods: A cross-sectional survey, which was carried out on patients attending Outside Patient Department (OPD) of dental college of King Georges Medical University, Lucknow, India. All the patients who consumed tobacco attending the Dental College were asked to participate in the study. The questionnaire was written in English/ Hindi (local language). Participation in this study was voluntary and the questionnaire was anonymous and self-administered. The proposal of this survey had been approved by the ethical committee of institution. Informed consent was obtained from all the participants. Results: Prevalence of tobacco user attending the Dental OPD was 46.4%. Male tobacco user represented 85.9%. Smokeless tobacco (57%) user were more than smoking (1.4%) and 18.9% were using both smokeless and smoking tobacco. 40.7% start using tobacco since less than 5 years. 55.3% uses tobacco after get up in the morning. 87.1% tobacco user knows that it cause cancer. 54.8% respond that warning sign on packet/pouch effect on mind but due to addiction, it would not work out. 54.8% attempted for quitting but not successful. 90.0% willing to quit in future if facility provide. Conclusion: Higher prevalence of tobacco usage among study population and will to quit in future shows need of cessation clinic in every dental institution in India.

Keywords: tobacco, knowledge, practice, counselling

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1284 Investigation of Possible Precancerous Viral Markers in Dental Follicles of Asymptomatic Impacted Teeth

Authors: Serap Keskin Tunç, Cennet Neslihan Eroğlu, Sevinç Şahin, Selda Seçkin

Abstract:

It has been suggested that various viruses may play a role in the pathogenesis of cancerous oral lesions in the literature. The aim of this study was to investigate the presence of both possible precancerous viral markers (HPV, HHV8, HSV1, HSV2, and EBV), and p53 and Ki-67 in the dental follicles of asymptomatic impacted teeth. A hundred healthy volunteers, older than 18 years old, included in the study. Dental follicles of extracted impacted teeth were excised and fixated in 10% formaldehyde. Histopathological and immunohistochemical examinations using HPV (containing HPV 8 and HPV 11), p16 (containing HPV 16), HHV8, HSV1, HSV2, EBV, p53 and Ki-67 antibodies were carried out. Also, the immunohistochemical results were correlated with the clinicopathological feature by Chi-square test statistically No dysplasia or neoplasm was observed. 62% of the cases were positive for p16, 32% were positive for EBV, 26% were positive for HSV1, immunohistochemically. All cases were immunonegative for HPV, HSV2, and HHV8. There was statistically significant correlation between overexpression of p53 with both EBV and p16 positivity (p<0.05). Direct correlation between higher expression of Ki-67 between EBV immunopositivity was detected (p<0.05). Thus, these viruses may be suggested to show trophism to the dental follicles acting as a reservoir. In conclusion, all dental follicles of extracted impacted teeth should be examined histopathologically in order to detect and prevent possible viral oncogenesis.

Keywords: dental follicles, Ki67, p53, precancerous markers viral markers

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1283 Border Between the Violation of Dental Ethics and the Occurrence of Dental Malpractice

Authors: Saimir Heta, Rialda Xhizdari, Kers Kapaj, Ilma Robo

Abstract:

Background: The interests of both individuals involved, both the dentist with his professionalism, and the patient who claims and expects the proper professional dental service, are determined in cases of dental malpractice. The latter is a phenomenon that is also wearing the "cloak" of bilateral manipulations, which in themselves require strong legal control to regulate the relations between the involved parties. The two individuals are involved both individually and even professionally and emotionally, with support in the "ultimate" interests of the two people, which in the case of conflicts or grievances, which as a result are transported to the family or society of the affected individual. Main text: The reason for malpractice is the most difficult part to find and then to interpret. It can be professional in the view of "so much I know how to do, so much done", or in the view of the impossibility of individual health conditions to achieve high professional expectations. But, the reason can also be individual with the intention of doing bad without reason or with the source of an unhealthy mind and the source of malicious thinking. The professional himself is a human being and as such may be under the effect of individual treatments or vices, therefore causing misuse, a case that must be distinguished from intentional misuse and which must be judged for the results or damages caused by the professional based on criminal law. Conclusions: Malpractice in some cases may be unavoidable, beyond the good intention of the dental intervention, which should be well understood by both parties involved in this relationship. Malpractice is not necessarily related only to difficult clinical cases, but sometimes also appears as a random deviation of a dental treatment with a welldefined professional protocol. The legal support in the interpretation of malpractice cases should be much more specific according to previous cases, this practice specifically, perhaps also according to different religious states.

Keywords: dental ethics, malpractice, professional dental service, legal support

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1282 Risk Management in Healthcare Sector in Turkey: A Dental Hospital Case Study

Authors: Pırıl Tekin, Rızvan Erol

Abstract:

Risk management has become very important and popular in developing countries in recent years. Especially making patient and employee health and safety issues compulsory in the hospitals, raised the number of studies in Turkey. Also risk management become more important for hospital senior management from clinics to the laboratories. Because quality is really important to be chosen for both patients to consult and employees to prefer to work. And also risk management studies can lead to hospital management team about future works and methods. By this point of view, this study is the risk assessment carried out in the biggest dental hospital in the south part of Turkey. This study was conducted as a research case study, covering two different health care place; A Clinic and A Laboratory. It shows that the problems in this dental hospital and how it can solve all.

Keywords: risk management, healthcare, dental hospital, quality management

Procedia PDF Downloads 379