WorldWideScience

Sample records for biomedical and dental materials

  1. Japanese research and development on metallic biomedical, dental, and healthcare materials

    Science.gov (United States)

    Niinomi, Mitsuo; Hanawa, Takao; Narushima, Takayuki

    2005-04-01

    There is considerable demand for metallic materials for use in medical and dental devices. Metals and alloys are widely used as biomedical materials and are indispensable in the medical field. In dentistry, metal is used for restorations, orthodontic wires, and dental implants. This article describes R&D on metallic biomaterials primarily conducted by the members of the Japan Institute of Metals.

  2. Potential of Electrospun Nanofibers for Biomedical and Dental Applications

    Directory of Open Access Journals (Sweden)

    Muhammad Zafar

    2016-01-01

    Full Text Available Electrospinning is a versatile technique that has gained popularity for various biomedical applications in recent years. Electrospinning is being used for fabricating nanofibers for various biomedical and dental applications such as tooth regeneration, wound healing and prevention of dental caries. Electrospun materials have the benefits of unique properties for instance, high surface area to volume ratio, enhanced cellular interactions, protein absorption to facilitate binding sites for cell receptors. Extensive research has been conducted to explore the potential of electrospun nanofibers for repair and regeneration of various dental and oral tissues including dental pulp, dentin, periodontal tissues, oral mucosa and skeletal tissues. However, there are a few limitations of electrospinning hindering the progress of these materials to practical or clinical applications. In terms of biomaterials aspects, the better understanding of controlled fabrication, properties and functioning of electrospun materials is required to overcome the limitations. More in vivo studies are definitely required to evaluate the biocompatibility of electrospun scaffolds. Furthermore, mechanical properties of such scaffolds should be enhanced so that they resist mechanical stresses during tissue regeneration applications. The objective of this article is to review the current progress of electrospun nanofibers for biomedical and dental applications. In addition, various aspects of electrospun materials in relation to potential dental applications have been discussed.

  3. Biomedical Materials

    Institute of Scientific and Technical Information of China (English)

    CHANG Jiang; ZHOU Yanling

    2011-01-01

    @@ Biomedical materials, biomaterials for short, is regarded as "any substance or combination of substances, synthetic or natural in origin, which can be used for any period of time, as a whole or as part of a system which treats, augments, or replaces any tissue, organ or function of the body" (Vonrecum & Laberge, 1995).Biomaterials can save lives, relieve suffering and enhance the quality of life for human being.

  4. Biomedical composites materials, manufacturing and engineering

    CERN Document Server

    Davim, J Paulo

    2013-01-01

    Composite materials are engineered materials, made from two or more constituents with significantly different physical or chemical properties which remain separate on a macroscopic level within the finished structure. Due to their special mechanical and physical properties they have the potential to replace conventional materials in various fields such as the biomedical industry.

  5. Mercury and Other Biomedical Waste Management Practices among Dental Practitioners in India

    Directory of Open Access Journals (Sweden)

    Raghuwar D. Singh

    2014-01-01

    Full Text Available Objectives. The objective of the study was to assess the awareness and performance towards dental waste including mercury management policy and practices among the dental practitioners in North India. Materials and Methods. An epidemiologic survey was conducted among 200 private dental practitioners. The survey form was composed of 29 self-administered questions frame based on knowledge, attitude, and those regarding the practices of dentists in relation to dental health-care waste management. The resulting data were coded and a statistical analysis was done. Results and Discussion. About 63.7% of the dentists were not aware of the different categories of biomedical waste generated in their clinics. Only 31.9% of the dentists correctly said that outdated and contaminated drugs come under cytotoxic waste. 46.2% said they break the needle and dispose of it and only 21.9% use needle burner to destroy it. 45.0% of the dentists dispose of the developer and fixer solutions by letting them into the sewer, 49.4% of them dilute the solutions and let them into sewer and only 5.6% return them to the supplier. About 40.6% of the dentists dispose of excess silver amalgam by throwing it into common bin. Conclusion. It was concluded that not all dentists were aware of the risks they were exposed to and only half of them observe infection control practices.

  6. Switchable and responsive surfaces and materials for biomedical applications

    CERN Document Server

    Zhang, Johnathan

    2015-01-01

    Surface modification of biomaterials can ultimately determine whether a material is accepted or rejected from the human body, and a responsive surface can further make the material ""smart"" and ""intelligent"". Switchable and Responsive Surfaces and Materials for Biomedical Applications outlines synthetic and biological materials that are responsive under different stimuli, their surface design and modification techniques, and applicability in regenerative medicine/tissue engineering,  drug delivery, medical devices, and biomedical diagnostics. Part one provides a detailed overview of swit

  7. Fatigue, Wear and Cracking of Dental Materials

    Directory of Open Access Journals (Sweden)

    Traian Eugen Bolfa

    2015-07-01

    Full Text Available Evaluation of the method of failure and crack propagation in dental metals, ceramics and polymer composite materials associated with occlusal activity are associated with contact, twisting and sliding modes. Such loads can result in various combinations of damage due to fatigue and wear. In order to increase sustainability and longevity the dental materials must demonstrate sufficient strength to dynamic stresses. In the case of masticatory forces associated with high contact tensions, the contact area of the superficial layer is under a state of specialcomplex voltage. Variations in the material or the structure, impurities, scratches and voids can directly influence the structural integrity of the material and result in microscopic cracks. These cracks propagate under repeated cyclic loading leading to dental restoration failure.

  8. Translucency measurements in teeth and dental materials

    Science.gov (United States)

    Rawicz, Andrew H.; Melnyk, Ivan; Kowalski, Pawel

    2003-06-01

    Exact color matching of dental restorative materials to vital teeth is a difficult task. There are several reasons for this difficulty and they will be elaborated upon in the presentation. One of the most important reasons is the fact that teeth, as well as dental restorative materials are translucent, and thus the color impression is a product of light scattering, back scattering, transmission, and spectral modifications inside of these objects. Classic colorimetry is insufficient to provide an exact color match. Additional information about the translucency factor of the considered object (material and geometry) is necessary to provide full reproducibility. Translucency has a direct effect on perceived brightness. In this article we describe the TransluDent, a complementary product to ColorDent, which measures translucency of teeth and dental materials. TransluDent determines translucency by measuring light transmitted through an object and light scattered inside of the object. The translucency measurements were performed on two groups of subjects. One group consisted of people in their twenties and the second group of subjects was in fifties. For comparison several sets of dental shade-guides were also tested. The great discrepancy in translucency factor between human teeth and popular on the market shades may explain difficulty in color matching of dental restorative materials to teeth.

  9. Tooth regeneration: challenges and opportunities for biomedical material research.

    Science.gov (United States)

    Du, Chang; Moradian-Oldak, Janet

    2006-03-01

    Tooth regeneration presents many challenges to researchers in the fields of biology, medicine and material science. This review considers the opportunities for biomedical material research to contribute to this multidisciplinary endeavor. We present short summaries and an overview on the collective knowledge of tooth developmental biology, advances in stem-cell research, and progress in the understanding of the tooth biomineralization principles as they provide the foundation for developing strategies for reparative and regenerative medicine. We emphasize that various biomaterials developed via biomimetic strategies have great potential for tooth tissue engineering and regeneration applications. The current practices in tooth tissue engineering approaches and applications of biomimetic carriers or scaffolds are also discussed.

  10. Processing silk hydrogel and its applications in biomedical materials.

    Science.gov (United States)

    Wang, Hai-Yan; Zhang, Yu-Qing

    2015-01-01

    This review mainly introduces the types of silk hydrogels, their processing methods, and applications. There are various methods for hydrogel preparation, and many new processes are being developed for various applications. Silk hydrogels can be used in cartilage tissue engineering, drug release materials, 3D scaffolds for cells, and artificial skin, among other applications because of their porous structure and high porosity and the large surface area for growth, migration, adhesion and proliferation of cells that the hydrogels provide. All of these advantages have made silk hydrogels increasingly attractive. In addition, silk hydrogels have wide prospects for application in the field of biomedical materials.

  11. Advances in dental materials.

    Science.gov (United States)

    Fleming, Garry J P

    2014-05-01

    The dental market is replete with new resorative materials marketed on the basis of novel technological advances in materials chemistry, bonding capability or reduced operator time and/or technique sensitivity. This paper aims to consider advances in current materials, with an emphasis on their role in supporting contemporary clinical practice.

  12. Functionalization of biomedical materials using plasma and related technologies

    Science.gov (United States)

    Zhao, Ying; Yeung, Kelvin W. K.; Chu, Paul K.

    2014-08-01

    Plasma techniques are important to biomedical engineering and surface modification. By modifying selective surface characteristics, conventional materials can be designed with superior biological properties while the favorable bulk materials properties can be retained. In this mini-review, recent progress pertaining to surface modification of Mg-based and polymer-based biomaterials by plasma-based techniques such as gas or metal ion implantation, dual metal and gas ion implantation, as well as plasma immersion ion implantation and deposition is described. Plasma-based surface modification is promising in elevating the cell biocompatibility, blood compatibility, and antibacterial properties of Mg-based and polymer-based biomaterials and expected to be extensively applied to biomaterials.

  13. Side Effects and Complications of Dental Materials on Oral Cavity

    Directory of Open Access Journals (Sweden)

    Z. Atai

    2007-01-01

    Full Text Available Development of dental materials has had a great impact on the modern dentistry. The materials ranging from polymers to metals have different applications in dentistry. Besides their important role in healing or improving the function of oral tissues, the materials may show side effects which may, in some cases, lead to severe lesions. In this review the side effects have been summarized considering a new classification for dental materials according to the duration of their applications as temporary or permanent materials. The side effects of the materials are then discussed based on clinical and cellular views.

  14. Evaluation of patients with oral lichenoid lesions by dental patch testing and results of removal of the dental restoration material

    Directory of Open Access Journals (Sweden)

    Emine Buket Şahin

    2016-12-01

    Full Text Available Background and Design: Oral lichenoid lesions (OLL are contact stomatitis characterized by white reticular or erosive patches, plaque-like lesions that are clinically and histopathologically indistinguishable from oral lichen planus (OLP. Amalgam dental fillings and dental restoration materials are among the etiologic agents. In the present study, it was aimed to evaluate the standard and dental series patch tests in patients with OLL in comparison to a control group and evaluate our results. Materials and Methods: Thirty-three patients with OLL or OLP and 30 healthy control subjects, who had at least one dental restoration material and/or dental filling, were included in the study. Both groups received standard series and dental patch test and the results were evaluated simultaneously. Results: The most frequent allergens in the dental series patch test in the patient group were palladium chloride (n=4; 12.12% and benzoyl peroxide (n=2, 6.06%. Of the 33 patients with OLL; 8 had positive reaction to allergents in the standard patch test series and 8 had positive reaction in the dental patch test series. There was no significant difference in the rate of patch test reaction to the dental and standard series between the groups. Ten patients were advised to have the dental restoration material removed according to the results of the patch tests. The lesions improved in three patients [removal of all amalgam dental fillings (n=1, replacement of all amalgam dental fillings with an alternative filling material (n=1 and replacement of the dental prosthesis (n=1] following the removal or replacement of the dental restoration material. Conclusion: Dental patch test should be performed in patients with OLL and dental restoration material. Dental filling and/or prosthesis should be removed/replaced if there is a reaction against a dental restoration material-related allergen.

  15. A Review of Biomedical Composite Materials

    Institute of Scientific and Technical Information of China (English)

    吴珊珊

    2013-01-01

    This article addresses the review of the biomedical composite materials.It introduces the operational definition,the classification of biomedical composite materials,and its constituents within itself.In this thesis,the last part presents the application of this kind of material.By writing this paper,I hope that people will get a comprehensive knowledge of the biomedical composite material and make further and deeper research in this material by which way to animate the material science industry.

  16. Dental materials for cleft palate repair.

    Science.gov (United States)

    Sharif, Faiza; Ur Rehman, Ihtesham; Muhammad, Nawshad; MacNeil, Sheila

    2016-04-01

    Numerous bone and soft tissue grafting techniques are followed to repair cleft of lip and palate (CLP) defects. In addition to the gold standard surgical interventions involving the use of autogenous grafts, various allogenic and xenogenic graft materials are available for bone regeneration. In an attempt to discover minimally invasive and cost effective treatments for cleft repair, an exceptional growth in synthetic biomedical graft materials have occurred. This study gives an overview of the use of dental materials to repair cleft of lip and palate (CLP). The eligibility criteria for this review were case studies, clinical trials and retrospective studies on the use of various types of dental materials in surgical repair of cleft palate defects. Any data available on the surgical interventions to repair alveolar or palatal cleft, with natural or synthetic graft materials was included in this review. Those datasets with long term clinical follow-up results were referred to as particularly relevant. The results provide encouraging evidence in favor of dental and other related biomedical materials to fill the gaps in clefts of lip and palate. The review presents the various bones and soft tissue replacement strategies currently used, tested or explored for the repair of cleft defects. There was little available data on the use of synthetic materials in cleft repair which was a limitation of this study. In conclusion although clinical trials on the use of synthetic materials are currently underway the uses of autologous implants are the preferred treatment methods to date.

  17. Self-folding devices and materials for biomedical applications.

    Science.gov (United States)

    Randall, Christina L; Gultepe, Evin; Gracias, David H

    2012-03-01

    Because the native cellular environment is 3D, there is a need to extend planar, micro- and nanostructured biomedical devices to the third dimension. Self-folding methods can extend the precision of planar lithographic patterning into the third dimension and create reconfigurable structures that fold or unfold in response to specific environmental cues. Here, we review the use of hinge-based self-folding methods in the creation of functional 3D biomedical devices including precisely patterned nano- to centimeter scale polyhedral containers, scaffolds for cell culture and reconfigurable surgical tools such as grippers that respond autonomously to specific chemicals.

  18. Theoretical and practical aspects regarding the development and control of microbial biofilms attached to the surface of dental materials and dental prostheses in particular

    OpenAIRE

    Zisi, Sonila; Bortollini, Sergio; Muntianu, Ligia; Papakoca, Kiro; Mihai BURLIBASA

    2012-01-01

    Microbial biofilms play an essential role in oral pathology, in the etiology of dental caries, periodontopathy, but also in surface contamination of dental materials (and here we refer to prosthetic material such as acrylic materials usedfor dentures, occlusal rims, try-in dentures, dental alloys used in fixed dental restorations, impression materials, etc.)

  19. Dental implants from functionally graded materials.

    Science.gov (United States)

    Mehrali, Mehdi; Shirazi, Farid Seyed; Mehrali, Mohammad; Metselaar, Hendrik Simon Cornelis; Kadri, Nahrizul Adib Bin; Osman, Noor Azuan Abu

    2013-10-01

    Functionally graded material (FGM) is a heterogeneous composite material including a number of constituents that exhibit a compositional gradient from one surface of the material to the other subsequently, resulting in a material with continuously varying properties in the thickness direction. FGMs are gaining attention for biomedical applications, especially for implants, owing to their reported superior composition. Dental implants can be functionally graded to create an optimized mechanical behavior and achieve the intended biocompatibility and osseointegration improvement. This review presents a comprehensive summary of biomaterials and manufacturing techniques researchers employ throughout the world. Generally, FGM and FGM porous biomaterials are more difficult to fabricate than uniform or homogenous biomaterials. Therefore, our discussion is intended to give the readers about successful and obstacles fabrication of FGM and porous FGM in dental implants that will bring state-of-the-art technology to the bedside and develop quality of life and present standards of care.

  20. PREFACE Surface Modifications and Functionalization of Materials for Biomedical Applications

    Science.gov (United States)

    Endrino, Jose Luis; Puértolas, Jose A.; Albella, Jose M.

    2010-11-01

    Conference photograph This special issue contains selected papers which were presented as invited and contributed communications at the workshop entitled 'Surface modification and functionalization of materials for biomedical applications' (BIO-COAT 2010) which was held on 24 June 2010 in Zaragoza (Spain). The surface of a material plays a major role in its interaction with the biological medium. Processes related to the mechanical stability of articular devices in contact, osseointegration, thrombogenicity, corrosion and leaching, or the inflammatory response of rejection of a material, are clearly conditioned by the surface properties. Therefore, the modification or functionalization of surfaces can have an important impact on these issues. New techniques for functionalization by thin film deposition or surface treatments help to improve superficial properties, while understanding the interaction of the surface-biological medium is critical for their application in new devices. Jointly organized by the Spanish Materials Research Society, BIO-COAT 2010 provided an open forum to discuss the progress and latest developments in thin film processing and the engineering of biomaterials. Invited lectures were particularly aimed at providing overviews on scientific topics and were given by recognized world-class scientists. Two of them have contributed with a proceedings article to this selected collection (articles 012001 and 012008). The contributed communications were focused on particular cutting-edge aspects of thin film science and functionalization technologies for biomaterials, showing the major scientific push of Spanish research groups in the field. The 2010 BIO-COAT conference was organized along four main topics: (1) functionalization and texture on surfaces, (2) tribology and corrosion, (3) the surface modification of biomaterials, and (4) surface-biological environment interactions. The papers published in this volume were accepted for publication after

  1. Psychophysiological reactivity of currently dental phobic-, remitted dental phobic- and never-dental phobic individuals during exposure to dental-related and other affect-inducing materials.

    Science.gov (United States)

    Wannemueller, André; Adolph, Dirk; Joehren, Hans-Peter; Blackwell, Simon E; Margraf, Jürgen

    2017-03-01

    Psychophysiological responses indicating the preparation of defensive behaviour, such as heart rate (HR)-increase and startle-response (SR) potentiation, have often been reported amongst individuals suffering from phobic disorders when exposed to phobia-related information. Although exposure is widely considered the 'gold standard' for treatment of Specific Phobia, it is unclear to what extent psychophysiological defensive response patterns change following treatment, and whether any changes are maintained. We assessed the acoustic SR- and HR-response to neutral, positive, negative and phobia-related pictures and sounds in 41 individuals currently suffering from dental phobia, 22 formerly dental phobic individuals who had remitted following an exposure-based treatment eight months prior to assessment, and 29 control individuals with no history of dental phobia. We observed SR-potentiation to dental-related stimuli in controls combined with HR-deceleration. In contrast, amongst phobic individuals SR-potentiation was accompanied by HR-acceleration to dental pictures. Successfully treated individuals showed inhibited startle reactivity in combination with HR-deceleration to dental related materials of both modalities. Our findings suggest inappropriate fight-flight preparation amongst individuals with dental phobia, reflecting overactivation of the defensive system. However, successful treatment results in inhibited physiological defence preparation, with remitted individuals displaying a response pattern that differed from that of phobic individuals and controls.

  2. Copper release from dental prosthetic crowns, dental materials, and human teeth into acetic acid.

    Science.gov (United States)

    Kalicanin, Biljana M; Nikolić, Ruzica S

    2010-01-01

    This article examines the dilution of the ion of copper from human teeth and dental prosthetic crowns in 4% CH(3)COOH during a period of 24 hr at room temperature. The content of the diluted copper in an acetate extract, as well as the overall content of this metal in the samples, was determined by means of a potentiometric stripping analysis. The comparative measurements were carried out using the furnace atomic absorption spectrophotometry technique, which is recommended by the International Standards (ISO 6872:2008; ISO 24234:2004) as a method for quality control of dental-prosthetic material (dental ceramic, metal restorative materials, dental amalgams) in the process of checking for heavy metals. During a 24-hr period in 4% CH(3)COOH at a temperature of 25 degrees C, approximately 72% of the overall copper was released from the tooth. The percentage of the released copper from baby teeth is higher, ranging from 88 to 92%, which is probably a consequence of the bone tissue being in development, its infirmity, and inadequate stability. On these conditions, approximately 72% of the overall copper was released from the dental-ceramic prosthetic crowns.

  3. A simplified model for biomedical waste management in dental practices - A pilot project at Thane, India

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    Om N Baghele

    2013-01-01

    Full Text Available A lot of biomedical waste (BMW is generated in dental practices, which can be hazardous to the environment as well as to those who come in contact with the materials, if not dealt with appropriately. Most of the rules world-wide are not specific for dental BMW management and hinder easy understanding by dental practitioners. Because of lack of clear-cut guidelines either from Dental Council of India or Government of India or Indian Dental Association (IDA on disposal of dental wastes, this article is designed to explore and review on these issues and formulate a simplified scheme. The guidelines by the Maharashtra Pollution Control Board from the directives of The Ministry of Environment and Forests, Government of India through BMW (Management and Handling Rules, 1998, (BMW-MH-98, similar guidelines being followed elsewhere in the world, the local BMW disposal company′s rules and the IDA′s Clinic Standardization Program guidelines. We developed and implemented a simplified waste segregation protocol for practicing dentists and dental hospitals. A methodological dental waste segregation protocol was required considering its disposal and ill-effects on health and the environment. The simplified scheme provided a good model to be followed in developing countries like India. The scheme improved understanding among dentists because of its self-explanatory nature.

  4. Dental perspective on biomedical waste and mercury management: A knowledge, attitude, and practice survey

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    Ashima Garg Sood

    2011-01-01

    Conclusions: There is need for education regarding hazards associated with improper waste disposal at all levels of dental personnel. It is imperative that waste should be segregated and disposed off in a safe manner to protect the environment as well as human health.

  5. Microfabrication materials for biomedical microdevices

    Science.gov (United States)

    Hansford, Derek James

    Major hurdles to the implementation of microfabricated devices for therapeutic applications include materials processing and biocompatibility issues. This dissertation reports research on improving the materials selection and fabrication for biomedical microdevices, using a microfabricated immunoisolation biocapsule as an example. Two material classes in the microfabrication protocol were examined based on the requirements determined for biomedical microdevices: the adhesive layer for bonding devices to encapsulate delicate biological substances and the thin film structural materials for surface structures, such as the biocapsule membrane. The major requirements for the adhesive layer material included non-cytotoxicity during bonding, adhesive strength, and durability under physiological conditions. Low glassy-phase transition temperature (Tg) methacrylates were found to be suitable candidates for adhesives of biomedical microdevices. A comparison study of poly propy1methacrylate (PPMA), poly (butyl, ethyl) methacrylate (PBEMA), and the higher Tg PMMA showed that all of the methacrylates had similar biocompatibility, adhesive strength, and durability. The adhesive strengths were found to be suitable for the adhesion of biomedical microdevices, as shown by measurement using a pressurized plate test and the current use of PMMA as bone cement. None of the methacrylates showed evidence of cytotoxicity, as measured by both optical and cytometric cell culture cytotoxicity tests. A protocol for the selective placement of smooth, thin films of PPMA using a Gel-PakTM transfer substrate was developed and demonstrated. The major requirements determined for the thin film structural materials were based on processing, mechanical, and biological parameters. Several candidates were identified as for structural materials based on these requirements: polycrystalline silicon. silicon nitride, fluoropolymers, PMMA, and silicone. A new fabrication protocol was developed to allow the

  6. Degree of conversion and microhardness of dental composite resin materials

    Science.gov (United States)

    Marovic, D.; Panduric, V.; Tarle, Z.; Ristic, M.; Sariri, K.; Demoli, N.; Klaric, E.; Jankovic, B.; Prskalo, K.

    2013-07-01

    Dental composite resins (CRs) are commonly used materials for the replacement of hard dental tissues. Degree of conversion (DC) of CR measures the amount of the un-polymerized monomers in CR, which can cause adverse biological reactions and weakening of the mechanical properties. In the past, studies have determined the positive correlation of DC values determined by Fourier transform infrared spectroscopy (FT-IR) and microhardness (MH) values. The aim of this study was to establish whether MH can replace FTIR for the determination of DC of contemporary CR.

  7. Protection and Reinforcement of Tooth Structures by Dental Coating Materials

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    Toru Nikaido

    2012-10-01

    Full Text Available It has been proposed that a resin coating can serve as a means to protect dental structure after preparation of the tooth for indirect restorations, sealing the exposed dentin. The resin coating is applied on the cut surfaces immediately after tooth preparation and before making an impression by assembling a dentin bonding system and a flowable composite. Resin coatings minimize pulp irritation and improve the bond strength between a resin cement and tooth when bonding the restoration to tooth. Recently, thin-film coating dental materials based on all-in-one adhesive technology were introduced for resin coating of indirect restorations. The thin coating materials are applied in a single clinical step and create a barrier-like film layer on the prepared dentin. The thin coatings play an important role in protecting the dentin from physical, chemical, and biological irritation. In addition, these thin-film coating materials reportedly prevent marginal leakage beneath inlays or crown restorations. In light of the many benefits provided by such a protective layer, these all-in-one adhesive materials may therefore also have the potential to cover exposed root dentin surfaces and prevent caries formation. In this paper, recent progress of the dental coating materials and their clinical applications are reviewed.

  8. Recent advances and developments in composite dental restorative materials.

    Science.gov (United States)

    Cramer, N B; Stansbury, J W; Bowman, C N

    2011-04-01

    Composite dental restorations represent a unique class of biomaterials with severe restrictions on biocompatibility, curing behavior, esthetics, and ultimate material properties. These materials are presently limited by shrinkage and polymerization-induced shrinkage stress, limited toughness, the presence of unreacted monomer that remains following the polymerization, and several other factors. Fortunately, these materials have been the focus of a great deal of research in recent years with the goal of improving restoration performance by changing the initiation system, monomers, and fillers and their coupling agents, and by developing novel polymerization strategies. Here, we review the general characteristics of the polymerization reaction and recent approaches that have been taken to improve composite restorative performance.

  9. Degradation, fatigue, and failure of resin dental composite materials.

    Science.gov (United States)

    Drummond, J L

    2008-08-01

    The intent of this article is to review the numerous factors that affect the mechanical properties of particle- or fiber-filler-containing indirect dental resin composite materials. The focus will be on the effects of degradation due to aging in different media, mainly water and water and ethanol, cyclic loading, and mixed-mode loading on flexure strength and fracture toughness. Several selected papers will be examined in detail with respect to mixed and cyclic loading, and 3D tomography with multi-axial compression specimens. The main cause of failure, for most dental resin composites, is the breakdown of the resin matrix and/or the interface between the filler and the resin matrix. In clinical studies, it appears that failure in the first 5 years is a restoration issue (technique or material selection); after that time period, failure most often results from secondary decay.

  10. Degradation, Fatigue, and Failure of Resin Dental Composite Materials

    Energy Technology Data Exchange (ETDEWEB)

    Drummond, J.L. (UIC)

    2008-11-03

    The intent of this article is to review the numerous factors that affect the mechanical properties of particle- or fiber-filler-containing indirect dental resin composite materials. The focus will be on the effects of degradation due to aging in different media, mainly water and water and ethanol, cyclic loading, and mixed-mode loading on flexure strength and fracture toughness. Several selected papers will be examined in detail with respect to mixed and cyclic loading, and 3D tomography with multi-axial compression specimens. The main cause of failure, for most dental resin composites, is the breakdown of the resin matrix and/or the interface between the filler and the resin matrix. In clinical studies, it appears that failure in the first 5 years is a restoration issue (technique or material selection); after that time period, failure most often results from secondary decay.

  11. Side Effects and Complications of Dental Materials on Oral Cavity

    OpenAIRE

    Z. Atai; M. Atai

    2007-01-01

    Development of dental materials has had a great impact on the modern dentistry. The materials ranging from polymers to metals have different applications in dentistry. Besides their important role in healing or improving the function of oral tissues, the materials may show side effects which may, in some cases, lead to severe lesions. In this review the side effects have been summarized considering a new classification for dental materials according to the duration of their applications as te...

  12. Evaluation of patients with oral lichenoid lesions by dental patch testing and results of removal of the dental restoration material

    OpenAIRE

    Emine Buket Şahin; Fatma Çetinözman; Nihal Avcu; Ayşen Karaduman

    2016-01-01

    Background and Design: Oral lichenoid lesions (OLL) are contact stomatitis characterized by white reticular or erosive patches, plaque-like lesions that are clinically and histopathologically indistinguishable from oral lichen planus (OLP). Amalgam dental fillings and dental restoration materials are among the etiologic agents. In the present study, it was aimed to evaluate the standard and dental series patch tests in patients with OLL in comparison to a control group and evaluate our result...

  13. Titanium Nitride and Nitrogen Ion Implanted Coated Dental Materials

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    David W. Berzins

    2012-07-01

    Full Text Available Titanium nitride and/or nitrogen ion implanted coated dental materials have been investigated since the mid-1980s and considered in various applications in dentistry such as implants, abutments, orthodontic wires, endodontic files, periodontal/oral hygiene instruments, and casting alloys for fixed restorations. Multiple methodologies have been employed to create the coatings, but detailed structural analysis of the coatings is generally lacking in the dental literature. Depending on application, the purpose of the coating is to provide increased surface hardness, abrasion/wear resistance, esthetics, and corrosion resistance, lower friction, as well as greater beneficial interaction with adjacent biological and material substrates. While many studies have reported on the achievement of these properties, a consensus is not always clear. Additionally, few studies have been conducted to assess the efficacy of the coatings in a clinical setting. Overall, titanium nitride and/or nitrogen ion implanted coated dental materials potentially offer advantages over uncoated counterparts, but more investigation is needed to document the structure of the coatings and their clinical effectiveness.

  14. Evaluation of radiation effects on dental enamel hardness and dental restorative materials; Avaliacao do efeito da irradiacao na dureza do esmalte dental e de materiais odontologicos

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Lena Katekawa; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Supervisao de Radioquimica; Campos, Tomie Nakakuki [Sao Paulo Univ., SP (Brazil). Faculdade de Odontologia. Dept. de Protese

    2000-07-01

    This research presents the results of the microhardness of human dental enamel and of the following dental restorative materials: three dental porcelains - Ceramco II, Finesse and Noritake, and two resin restorative materials - Artglass and Targis, for materials submitted to different times of irradiation at the IEA-R1m nuclear reactor under a thermal neutron flux of 10{sup 12}n cm{sup -2}.s{sup -1} . The results obtained indicated that there is a decrease of the surface microhardness when the enamel is irradiated for 1 h and when dental materials are irradiated for 3 h. However, enamels irradiated for 30 min. did not show significant change of their surface hardness. Therefore, the selection of irradiation time is an important factor to be considered when irradiated teeth or dental materials are used in the investigations of their properties. (author)

  15. Biocompatibility of Resin-based Dental Materials

    OpenAIRE

    Keyvan Moharamzadeh; Ian M. Brook; Richard van Noort

    2009-01-01

    Oral and mucosal adverse reactions to resin-based dental materials have been reported. Numerous studies have examined thebiocompatibility of restorative dental materials and their components, and a wide range of test systems for the evaluation of the biological effects of these materials have been developed. This article reviews the biological aspects of resin-based dental materials and discusses the conventional as well as the new techniques used for biocompatibility assessment of dental mat...

  16. Clinical translation of biomedical materials and the key factors towards product registration

    Directory of Open Access Journals (Sweden)

    Yuan Yuan

    2014-04-01

    Full Text Available Biomedical materials have been developed for facilitating tissue regeneration and healing enhancement. Although research on biomedical materials has made great progress in material innovation and preclinical testing, the bottleneck is their translation from research and development to clinical applications; that is, the current rate of product registration and industrialization is low, which directly affects their clinical applications. In this paper, we introduce the basic features of biomedical materials towards the making of medical products and the experiences of our group in research and clinical translation of biomaterials for bone-tissue regeneration in the last few years. Based on our experience, we propose that the translational medicine platform (TMP is an effective route to facilitate the progress of biomedical materials from bench to bedside. Moreover, from the viewpoints of scientific technology and management, the functions of TMP were also addressed. Relationships among TMP, research institution, enterprise, and government were also explored from the viewpoints of technological innovation, chemical engineering integration, fund raising, and management. This paper provides a theoretical and practical reference for clinical translation of biomedical materials.

  17. Tribological behaviour of unveneered and veneered lithium disilicate dental material.

    Science.gov (United States)

    Figueiredo-Pina, C G; Patas, N; Canhoto, J; Cláudio, R; Olhero, S M; Serro, A P; Ferro, A C; Guedes, M

    2016-01-01

    The friction and wear behaviour of a lithium disilicate dental ceramic against natural dental enamel is studied, including the effect of the presence of a fluorapatite veneering upon the tribological properties of the material. The tribological behaviour was assessed using reciprocating pin-on-plate test configuration, at pH 3 and pH 7. The surface energy of the plates was determined, as well as the zeta potential of fluorapatite, lithium disilicate and enamel particles in artificial saliva. It was found that the friction and wear behaviour of the tested enamel/plate material tribocouples is less severe in unveneered plates. Initial surface roughness of the plate does not affect wear results. However the topography of the resulting wear track affects the corresponding wear loss: a smoother final wear track is associated with lower wear. The surface topography of the wear track, and thus the tribological performance of the tested materials, is very sensitive to the pH of the sliding solution. This is because the dissolution trend, wettability and surface charge of the used materials are pH dependent. Overall friction and wear are higher under basic pH conditions, especially when plates are veneered. A wear model is proposed that correlates the effect of the described parameters with the observed tribological behaviour at pH 7. Attained results show that fluorapatite coating of lithium disilicate dental crowns affects tooth/crown wear behaviour, resulting in increased wear of both the artificial crown and the opposing natural teeth. Coating should therefore be avoided in occlusal crown surfaces.

  18. Bioinspired Nanoscale Materials for Biomedical and Energy Applications

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Priyanka; Du, Dan; Lin, Yuehe

    2014-05-01

    The demand of green, affordable and environmentally sustainable materials has encouraged scientists in different fields to draw inspiration from nature in developing materials with unique properties such as miniaturization, hierarchical organization, and adaptability. Together with the exceptional properties of nanomaterials, over the past century, the field of bioinspired nanomaterials has taken huge leaps. While on one hand, the sophistication of hierarchical structures endow biological systems with multifunctionality, the synthetic control on the creation of nanomaterials enables the design of materials with specific functionalities. The aim of this review is to provide a comprehensive, up-to-date overview of the field of bioinspired nanomaterials, which we have broadly categorized into biotemplates and biomimics. We will discuss the application of bioinspired nanomaterials as biotemplates in catalysis, nanomedicine, immunoassays and in energy, drawing attention to novel materials such as protein cages. Further, the applications of bioinspired materials in tissue engineering and biomineralization will also be discussed.

  19. What should biomedical sciences education in dental schools achieve?

    Science.gov (United States)

    Lantz, M S; Chaves, J F

    1997-05-01

    Education for the first professional degree in dentistry is intended to produce graduates capable of offering a wide range of high quality dental services to the general public. More than that, it is expected that graduates will be firmly grounded in the scientific basis for their professional practices and be equipped to evaluate critically and integrate selectively new scientific findings that emerge during their professional lifetimes. In addition, they are expected to be able to work effectively with diverse patient populations and to conduct their practices with a high level of sensitivity to the ethical and psychosocial dimensions of patient care. Indiana University School of Dentistry has undergone a process of curriculum reform that has yielded a new first professional degree program. Its hallmarks are large, multidisciplinary courses (seven courses in the first two years) that are taught using a variety of strategies including problem-based learning in small groups as well as lectures. The biomedical sciences curriculum is concept-based. Students will demonstrate their understanding of science concepts and methods by applying them to the solution of research and health care problems. Biomedical sciences will be taught at a level that will provide a comprehensive understanding of the functioning of the human body in health and disease, allow students to assimilate the coming revolution in molecular medicine, and selectively use new diagnostics, preventives, and therapeutics that evolve as molecular biological technologies yield solutions to current medical and dental problems. Using the biomedical sciences curriculum as a vehicle, we will also achieve the goal of training dentists as critical thinkers, problem solvers, lifelong learners, and ethical practitioners, skillful in peer and self-evaluation, and cognizant of the psychosocial as well as biomedical perspective of health and disease.

  20. Potentiometric stripping analysis of lead and cadmium leaching from dental prosthetic materials and teeth

    OpenAIRE

    GORAN M. NIKOLIC; BILJANA M. KALICANIN; RUZICA S. NIKOLIC

    2004-01-01

    Potentiometric stipping analysis (PSA) was applied for the determination of lead and cadmium leaching from dental prosthetic materials and teeth. The soluble lead content in finished dental implants was found to be much lower than that of the individual components used for their preparation. Cadmium was not detected in dental implants and materials under the defined conditions. The soluble lead and cadmium content of teeth was slightly lower than the lead and cadmium content in whole teeth (w...

  1. Nanocomposite Apatite-biopolymer Materials and Coatings for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    L.F. Sukhodub

    2014-04-01

    Full Text Available The microoverview paper describes synthesis and characterization of novel third generation composite biomaterials and coatings which correspond to the second structural level of human bone tissue (HBT organization obtained at Sumy state university “Bionanocomposite” laboratory. To obtain such composites an animal collagen is usually used, which is not potentially safe for medical applications. That is why investigations were started using some other biopolymers to obtain composites close to the second level in the structural hierarchy of HBT. Proposed natural polymers (Na alginate, chitosan are the most perspective because they have bacteriostatic properties for a vast number of aerobic and anaerobic bacteria, high biocompatibility towards the connective tissue, low toxicity, an ability to improve regenerative processes during wounds healing, degradation ability with the creation of chemotaxic activity towards fibroblasts and osteoblasts. The formation of nanosized (25-75 nm calcium deficient hydroxyapatite (cdHA particles in the polymer scaffold approaches the derived material to the biogenic bone tissue, which can provide its more effective implantation. The influence of the imposition of static magnetic field on brushite (CaHPO4·2H2O crystallization was also investigated. It was shown that changing the magnetic field configuration could greatly affect crystallinity and texture of the derived particles. To increase the biocompatibility of existing medical implants (Ti–6Al 4V, Ti Ni, Mg the technology for obtaining bioactive coatings with corresponding mechanical, structural and morphology characteristics is developed in our laboratory. In this direction coatings based on cdHA in combination with biopolymer matrices (Na alginate, chitosan, are obtained in “soft” conditions using a thermal substrate technology. This technology was proposed by Japan scientists [1] and was sufficiently improved by us [2] in order to obtain coatings in

  2. Synthesis, toxicity, biocompatibility, and biomedical applications of graphene and graphene-related materials

    Directory of Open Access Journals (Sweden)

    Gurunathan S

    2016-05-01

    Full Text Available Sangiliyandi Gurunathan, Jin-Hoi Kim Stem Cell and Regenerative Biology, Konkuk University, Seoul, Republic of Korea Abstract: Graphene is a two-dimensional atomic crystal, and since its development it has been applied in many novel ways in both research and industry. Graphene possesses unique properties, and it has been used in many applications including sensors, batteries, fuel cells, supercapacitors, transistors, components of high-strength machinery, and display screens in mobile devices. In the past decade, the biomedical applications of graphene have attracted much interest. Graphene has been reported to have antibacterial, antiplatelet, and anticancer activities. Several salient features of graphene make it a potential candidate for biological and biomedical applications. The synthesis, toxicity, biocompatibility, and biomedical applications of graphene are fundamental issues that require thorough investigation in any kind of applications related to human welfare. Therefore, this review addresses the various methods available for the synthesis of graphene, with special reference to biological synthesis, and highlights the biological applications of graphene with a focus on cancer therapy, drug delivery, bio-imaging, and tissue engineering, together with a brief discussion of the challenges and future perspectives of graphene. We hope to provide a comprehensive review of the latest progress in research on graphene, from synthesis to applications. Keywords: biomedical applications, cancer therapy, drug delivery, graphene, graphene-related materials, tissue engineering, toxicity 

  3. Teeth and bones: applications of surface science to dental materials and related biomaterials

    Science.gov (United States)

    Jones, F. H.

    2001-05-01

    Recent years have seen a considerable upsurge in publications concerning the surface structure and chemistry of materials with biological or biomedical applications. Within the body, gas-solid interactions become relatively less significant and solid-liquid or solid-solid interfaces dominate, providing new challenges for the surface scientist. The current paper aims to provide a timely review of the use of surface analysis and modification techniques within the biomaterials field. A broad overview of applications in a number of related areas is given with particular attention focusing on those materials commonly encountered in dentistry and oral or maxillofacial implantology. Several specific issues of current interest are discussed. The interaction between synthetic and natural solids, both in the oral environment and elsewhere in the body is important in terms of adhesion, related stresses and strains and ultimately the longevity of a dental restoration, biomedical implant, or indeed the surrounding tissue. Exposure to body fluids, of course, can also affect stability, leading to the degradation or corrosion of materials within the body. Whilst this could potentially be harmful, e.g., if cytotoxic elements are released, it may alternatively provide a route to the preferential release of beneficial substances. Furthermore, in some cases, the controlled disintegration of a biomaterial is desirable, allowing the removal of an implant, e.g., without the need for further surgery. The presence of cells in the immediate bioenvironment additionally complicates the situation. A considerable amount of current research activity is targeted at the development of coatings or surface treatments to encourage tissue growth. If this is to be achieved by stimulating enhanced cell productivity, determination of the relationship between cell function and surface composition is essential.

  4. Effect of microwave power on EPR spectra of natural and synthetic dental biocompatible materials

    Directory of Open Access Journals (Sweden)

    Adamczyk Jakub

    2015-07-01

    Full Text Available Paramagnetic centers in the two exemplary synthetic and natural dental biocompatible materials applied in implantology were examined by the use of an X-band (9.3 GHz electron paramagnetic resonance (EPR spectroscopy. The EPR spectra were measured in the range of microwave power 2.2–70 mW. The aims of this work were to compare paramagnetic centers concentrations in different dental biocompatible materials and to determine the effect of microwave power on parameters of their EPR spectra. It is the very first and innovatory examination of paramagnetic centers in these materials. It was pointed out that paramagnetic centers existed in both natural (~1018 spin/g and synthetic (~1019 spin/g dental biocompatible materials, but the lower free radical concentration characterized the natural sample. Continuous microwave saturation of EPR spectra indicated that faster spin-lattice relaxation processes existed in synthetic dental biocompatible materials than in natural material. Linewidths (ΔBpp of the EPR spectra of the natural dental material slightly increased for the higher microwave powers. Such effect was not observed for the synthetic material. The broad EPR lines (ΔBpp: 2.4 mT, 3.9 mT, were measured for the natural and synthetic dental materials, respectively. Probably strong dipolar interactions between paramagnetic centers in the studied samples may be responsible for their line broadening. EPR spectroscopy is the useful experimental method in the examination of paramagnetic centers in dental biocompatible materials.

  5. Multi-material laser densification (MMLD) of dental restorations: Process optimization and properties evaluation

    Science.gov (United States)

    Li, Xiaoxuan

    This Ph.D. thesis proposes to investigate the feasibility of laser-assisted dental restoration and to develop a fundamental understanding of the interaction between laser beam and dental materials. Traditional dental restorations are produced by the porcelain-fused-to-metal (PFM) process, in which a dental restoration is cast from a metallic alloy and then coated with dental porcelains by multiple furnace-firing processes. PFM method is labor-intensive and hence very expensive. In order to fabricate dental restoration units faster and more cost-effectively, the Solid Freeform Fabrication (SFF) technique has been employed in this study. In particular, a Multi-Material Laser Densification (MMLD) process has been investigated for its potential to fabricate artificial teeth automatically from 3-D computer dental tooth files. Based on the principle of SFF, the MMLD process utilizes a micro-extruder system to deliver commercial dental alloy and porcelain slurry in a computer-controlled pattern line by line and layer by layer. Instead of firing the artificial tooth/teeth in a furnace, the extruded dental materials are laser scanned to convert the loose powder to a fully dense body. Different laser densification parameters including the densification temperature, laser output power, laser beam size, line dimension, ratio of the beam size to line width, beam scanning rate, processing atmosphere and pressure, dental powder state (powder bed or slurry), powder particle size, etc. have been used to evaluate their effects on the microstructures and properties of the laser densified dental body, and hence to optimize MMLD conditions. Furthermore, laser-scanning induced phase transformations in dental porcelains have been studied because the transformations have great impact on coefficient of thermal expansion (CTE) of dental porcelains, which should match that of dental alloy substrate. Since a single dental material line delivered by the MMLD system functions as a "construction

  6. Amino acid derivative-mediated detoxification and functionalization of dual cure dental restorative material for dental pulp cell mineralization.

    Science.gov (United States)

    Minamikawa, Hajime; Yamada, Masahiro; Iwasa, Fuminori; Ueno, Takeshi; Deyama, Yoshiaki; Suzuki, Kuniaki; Yawaka, Yasutaka; Ogawa, Takahiro

    2010-10-01

    Current dental restorative materials are only used to fill the defect of hard tissues, such as dentin and enamel, because of their cytotoxicity. Therefore, exposed dental pulp tissues in deep cavities must be first covered by a pulp capping material like calcium hydroxide to form a layer of mineralized tissue. However, this tissue mineralization is based on pathological reaction and triggers long-lasting inflammation, often causing clinical problems. This study tested the ability of N-acetyl cysteine (NAC), amino acid derivative, to reduce cytotoxicity and induce mineralized tissue conductivity in resin-modified glass ionomer (RMGI), a widely used dental restorative material having dual cure mechanism. Rat dental pulp cells were cultured on untreated or NAC-supplemented RMGI. NAC supplementation substantially increased the percentage of viable cells from 46.7 to 73.3% after 24-h incubation. Cell attachment, spreading, proliferative activity, and odontoblast-related gene and protein expressions increased significantly on NAC-supplemented RMGI. The mineralization capability of cells, which was nearly suppressed on untreated RMGI, was induced on NAC-supplemented RMGI. These improved behaviors and functions of dental pulp cells on NAC-supplemented RMGI were associated with a considerable reduction in the production of intracellular reactive oxygen species and with the increased level of intracellular glutathione reserves. These results demonstrated that NAC could detoxify and functionalize RMGIs via two different mechanisms involving in situ material detoxification and antioxidant cell protection. We believe that this study provides a new approach for developing dental restorative materials that enables mineralized tissue regeneration.

  7. Graphene based materials for biomedical applications

    Directory of Open Access Journals (Sweden)

    Yuqi Yang

    2013-10-01

    Full Text Available Graphene, a single layer 2-dimensional structure nanomaterial with unique physicochemical properties (e.g. high surface area, excellent electrical conductivity, strong mechanical strength, unparalleled thermal conductivity, remarkable biocompatibility and ease of functionalization, has received increasing attention in physical, chemical and biomedical fields. This article selectively reviews current advances of graphene based materials for biomedical applications. In particular, graphene based biosensors for small biomolecules (glucose, dopamine etc., proteins and DNA detection have been summarized; graphene based bioimaging, drug delivery, and photothermal therapy applications have been described in detail. Future perspectives and possible challenges in this rapidly developing area are also discussed.

  8. Biomedical and Clinical Importance of Mussel-Inspired Polymers and Materials.

    Science.gov (United States)

    Kaushik, Nagendra Kumar; Kaushik, Neha; Pardeshi, Sunil; Sharma, Jai Gopal; Lee, Seung Hyun; Choi, Eun Ha

    2015-11-11

    The substance secreted by mussels, also known as nature's glue, is a type of liquid protein that hardens rapidly into a solid water-resistant adhesive material. While in seawater or saline conditions, mussels can adhere to all types of surfaces, sustaining its bonds via mussel adhesive proteins (MAPs), a group of proteins containing 3,4-dihydroxyphenylalanine (DOPA) and catecholic amino acid. Several aspects of this adhesion process have inspired the development of various types of synthetic materials for biomedical applications. Further, there is an urgent need to utilize biologically inspired strategies to develop new biocompatible materials for medical applications. Consequently, many researchers have recently reported bio-inspired techniques and materials that show results similar to or better than those shown by MAPs for a range of medical applications. However, the susceptibility to oxidation of 3,4-dihydroxyphenylalanine poses major challenges with regard to the practical translation of mussel adhesion. In this review, various strategies are discussed to provide an option for DOPA/metal ion chelation and to compensate for the limitations imposed by facile 3,4-dihydroxyphenylalanine autoxidation. We discuss the anti-proliferative, anti-inflammatory, anti-microbial activity, and adhesive behaviors of mussel bio-products and mussel-inspired materials (MIMs) that make them attractive for synthetic adaptation. The development of biologically inspired adhesive interfaces, bioactive mussel products, MIMs, and arising areas of research leading to biomedical applications are considered in this review.

  9. Biomedical and Clinical Importance of Mussel-Inspired Polymers and Materials

    Directory of Open Access Journals (Sweden)

    Nagendra Kumar Kaushik

    2015-11-01

    Full Text Available The substance secreted by mussels, also known as nature’s glue, is a type of liquid protein that hardens rapidly into a solid water-resistant adhesive material. While in seawater or saline conditions, mussels can adhere to all types of surfaces, sustaining its bonds via mussel adhesive proteins (MAPs, a group of proteins containing 3,4-dihydroxyphenylalanine (DOPA and catecholic amino acid. Several aspects of this adhesion process have inspired the development of various types of synthetic materials for biomedical applications. Further, there is an urgent need to utilize biologically inspired strategies to develop new biocompatible materials for medical applications. Consequently, many researchers have recently reported bio-inspired techniques and materials that show results similar to or better than those shown by MAPs for a range of medical applications. However, the susceptibility to oxidation of 3,4-dihydroxyphenylalanine poses major challenges with regard to the practical translation of mussel adhesion. In this review, various strategies are discussed to provide an option for DOPA/metal ion chelation and to compensate for the limitations imposed by facile 3,4-dihydroxyphenylalanine autoxidation. We discuss the anti-proliferative, anti-inflammatory, anti-microbial activity, and adhesive behaviors of mussel bio-products and mussel-inspired materials (MIMs that make them attractive for synthetic adaptation. The development of biologically inspired adhesive interfaces, bioactive mussel products, MIMs, and arising areas of research leading to biomedical applications are considered in this review.

  10. Building biomedical materials layer-by-layer

    Directory of Open Access Journals (Sweden)

    Paula T. Hammond

    2012-05-01

    Full Text Available In this materials perspective, the promise of water based layer-by-layer (LbL assembly as a means of generating drug-releasing surfaces for biomedical applications, from small molecule therapeutics to biologic drugs and nucleic acids, is examined. Specific advantages of the use of LbL assembly versus traditional polymeric blend encapsulation are discussed. Examples are provided to present potential new directions. Translational opportunities are discussed to examine the impact and potential for true biomedical translation using rapid assembly methods, and applications are discussed with high need and medical return.

  11. Synthesis, characterization, and efficacy of antimicrobial chlorhexidine hexametaphosphate nanoparticles for applications in biomedical materials and consumer products

    Directory of Open Access Journals (Sweden)

    Barbour ME

    2013-09-01

    Full Text Available Michele E Barbour,1 Sarah E Maddocks,2 Natalie J Wood,1,3 Andrew M Collins3 1Oral Nanoscience, School of Oral and Dental Sciences, University of Bristol, Bristol, UK; 2Cardiff School of Health Sciences, Cardiff Metropolitan University, Cardiff, UK; 3Bristol Centre for Functional Nanomaterials, University of Bristol, Bristol, UK Abstract: Chlorhexidine (CHX is an antimicrobial agent that is efficacious against gram-negative and -positive bacteria and yeasts. Its mechanism of action is based on cell membrane disruption and, as such, it does not promote the development of bacterial resistance, which is associated with the widespread use of antibiotics. In this manuscript, we report the development of novel antimicrobial nanoparticles (NPs based on a hexametaphosphate salt of CHX. These are synthesized by instantaneous reaction between equimolar aqueous solutions of CHX digluconate and sodium hexametaphosphate, under room temperature and pressure. The reaction results in a stable colloid composed of highly negatively charged NPs (−50 mV, of size 20-160 nm. The NPs adhere rapidly to specimens of glass, titanium, and an elastomeric wound dressing, in a dose-dependent manner. The functionalized materials exhibit a gradual leaching of soluble CHX over a period of at least 50 days. The NP colloid is efficacious against methicillin-resistant Staphylococcus aureus (MRSA and Pseudomonas aeruginosa in both planktonic and biofilm conditions. These NPs may find application in a range of biomedical and consumer materials. Keywords: MRSA, biomaterials, chlorhexidine, drug delivery, slow release

  12. A useful and non-invasive microanalysis method for dental restoration materials

    Energy Technology Data Exchange (ETDEWEB)

    Hosoki, M., E-mail: hosoki@tokushima-u.ac.jp [Department of Fixed Prosthodontics, Institute of Health Biosciences, University of Tokushima Graduate School, 3-18-15 Kuramoto-cho, Tokushima 770-8504 (Japan); Satsuma, T.; Nishigawa, K.; Takeuchi, H. [General Dentistry, Tokushima University Hospital, 3-18-15 Kuramoto-cho, Tokushima 770-8504 (Japan); Asaoka, K. [Department of Biomaterials and Bioengineering, Institute of Health Biosciences, University of Tokushima Graduate School, 3-18-15 Kuramoto-cho, Tokushima 770-8504 (Japan)

    2012-12-01

    Highlights: Black-Right-Pointing-Pointer This method for the microanalysis of dental alloys is beneficial for patients with allergies to dental materials. Black-Right-Pointing-Pointer This metal sample is easy to mail it for inspection at specialist institutes. Black-Right-Pointing-Pointer This method can be also be used in general dental clinics. - Abstract: The elemental analysis of intraoral dental restorations provides considerable information for the treatment of dental metal allergy. Elemental analyses require specific instruments and complicated procedures, so this examination is not commonly carried out in private dental clinics. We describe a novel, simple and useful micro-analytical method for dental metal restorations. Micro metal dust was obtained by polishing the surface of restorative metal material with an unused silicone point (SUPER-SNAP). The metal dust on the silicone point was then rubbed onto adhesive tape, and this tape was covered with polyethylene film. The amount of metal dust material was <20 {mu}g. An energy dispersive X-ray fluorescence spectrometer was used to carry out the elementary analysis of the metal dust on the polyethylene film. Three types of dental metal alloy materials of known components were examined. The results of elementary analyses were compared with the specifications provided by the manufacturer. The same procedure was carried out for three dental metal restorations of an adult female volunteer in vivo. The results of elemental analyses for five alloy materials exactly matched the product specification. Three metal samples obtained from intraoral restoration were also available for elemental analyses. The distinct advantage of this method is that it enables sample extraction without an invasive effect for the restoration. The metal sample is in a polyethylene film, so it is easy to mail it for inspection at specialist institutes yet it can be also be used in general dental clinics.

  13. Potentiometric stripping analysis of lead and cadmium leaching from dental prosthetic materials and teeth

    Directory of Open Access Journals (Sweden)

    GORAN M. NIKOLIC

    2004-07-01

    Full Text Available Potentiometric stipping analysis (PSA was applied for the determination of lead and cadmium leaching from dental prosthetic materials and teeth. The soluble lead content in finished dental implants was found to be much lower than that of the individual components used for their preparation. Cadmium was not detected in dental implants and materials under the defined conditions. The soluble lead and cadmium content of teeth was slightly lower than the lead and cadmium content in whole teeth (w/w reported by other researchers, except in the case of a tooth with removed amalgam filling. The results of this work suggest that PSA may be a good method for lead and cadmium leaching studies for investigation of the biocompatibility of dental prosthetic materials.

  14. Synthesis, characterization and bioevaluation of drug-collagen hybrid materials for biomedical applications.

    Science.gov (United States)

    Voicu, Georgeta; Geanaliu-Nicolae, Ruxandra-Elena; Pîrvan, Adrian-Alexandru; Andronescu, Ecaterina; Iordache, Florin

    2016-08-30

    This work presents a study based on the preparation and characterization of drug-collagen hybrid materials. Materials used for obtaining drug-collagen hybrids were collagen type I (Coll) as matrix and fludarabine (F) and epirubicin (E) as hydrophilic active substances. After incorporation of drugs into Coll in different ratios, the obtained hybrid materials (Coll/F and Coll/E) could be used according to our results as potential drug delivery systems in medicine for the topical (local) treatment of cancerous tissues (e.g. the treatment of breast, stomach, lung, colorectal or advanced ovarian cancer). The materials were characterized considering their composition (by XRD, FT-IR and DTA-TG) and their morphology (by SEM). The delivery of drug was assessed by UV-vis. The in vitro citotoxicity demonstrates an antitumoral activity of the obtained hybrid materials and their potential use for biomedical applications as drug delivery systems in tumoral treatments.

  15. Artifacts in magnetic resonance imaging and computed tomography caused by dental materials.

    Directory of Open Access Journals (Sweden)

    Thomas Klinke

    Full Text Available BACKGROUND: Artifacts caused by dental restorations, such as dental crowns, dental fillings and orthodontic appliances, are a common problem in MRI and CT scans of the head and neck. The aim of this in-vitro study was to identify and evaluate the artifacts produced by different dental restoration materials in CT and MRI images. METHODS: Test samples of 44 materials (Metal and Non-Metal commonly used in dental restorations were fabricated and embedded with reference specimens in gelatin moulds. MRI imaging of 1.5T and CT scan were performed on the samples and evaluated in two dimensions. Artifact size and distortions were measured using a digital image analysis software. RESULTS: In MRI, 13 out of 44 materials produced artifacts, while in CT 41 out of 44 materials showed artifacts. Artifacts produced in both MRI and CT images were categorized according to the size of the artifact. SIGNIFICANCE: Metal based restoration materials had strong influence on CT and less artifacts in MRI images. Rare earth elements such as Ytterbium trifluoride found in composites caused artifacts in both MRI and CT. Recognizing these findings would help dental materials manufacturers and developers to produce materials which can cause less artifacts in MRI and CT images.

  16. Surface tailoring of inorganic materials for biomedical applications

    CERN Document Server

    Rimondini, Lia; Vernè, Enrica

    2012-01-01

    This e-book provides comprehensive information on technologies for development and characterization of successful functionalized materials for biomedical applications relevant to surface modification.

  17. IN VITRO TESTING – AN ESENTIAL METHOD FOR EVALUATING THE PERFORMANCE OF DENTAL MATERIALS AND DEVICES

    Directory of Open Access Journals (Sweden)

    Anca VIŢALARIU

    2015-06-01

    Full Text Available Dentistry is unique among biomaterials specialties as to the large variety of materials used, and nature of the challenges they must resist. Intra-oral service demands materials adapted to a warm and moist environment, resisting the attack of digestive acids and enzymes. The materials subjected to mechanical forces should preserve their strength, fatigue and wear characteristics, for accomplishing their function. The wide range of materials available for restorative dentistry demands knowledge of their relative strengths and trade-offs, and offers the opportunity for many interesting lines of research. The spectrum extensively ranges from elastic impression materials to extremely stiff metal and ceramic appliances, so that familiarity with a variety of mechanical testing situations is required from a well-rounded dental materials laboratory. Evaluating the mechanical and wear characteristics of dental restorative materials and analyzing the durability of adhesives is critical to the development of improved dental devices

  18. A useful and non-invasive microanalysis method for dental restoration materials

    Science.gov (United States)

    Hosoki, M.; Satsuma, T.; Nishigawa, K.; Takeuchi, H.; Asaoka, K.

    2012-12-01

    The elemental analysis of intraoral dental restorations provides considerable information for the treatment of dental metal allergy. Elemental analyses require specific instruments and complicated procedures, so this examination is not commonly carried out in private dental clinics. We describe a novel, simple and useful micro-analytical method for dental metal restorations. Micro metal dust was obtained by polishing the surface of restorative metal material with an unused silicone point (SUPER-SNAP). The metal dust on the silicone point was then rubbed onto adhesive tape, and this tape was covered with polyethylene film. The amount of metal dust material was <20 μg. An energy dispersive X-ray fluorescence spectrometer was used to carry out the elementary analysis of the metal dust on the polyethylene film. Three types of dental metal alloy materials of known components were examined. The results of elementary analyses were compared with the specifications provided by the manufacturer. The same procedure was carried out for three dental metal restorations of an adult female volunteer in vivo. The results of elemental analyses for five alloy materials exactly matched the product specification. Three metal samples obtained from intraoral restoration were also available for elemental analyses. The distinct advantage of this method is that it enables sample extraction without an invasive effect for the restoration. The metal sample is in a polyethylene film, so it is easy to mail it for inspection at specialist institutes yet it can be also be used in general dental clinics.

  19. Biomedical signals, imaging, and informatics

    CERN Document Server

    Bronzino, Joseph D

    2014-01-01

    Known as the bible of biomedical engineering, The Biomedical Engineering Handbook, Fourth Edition, sets the standard against which all other references of this nature are measured. As such, it has served as a major resource for both skilled professionals and novices to biomedical engineering.Biomedical Signals, Imaging, and Informatics, the third volume of the handbook, presents material from respected scientists with diverse backgrounds in biosignal processing, medical imaging, infrared imaging, and medical informatics.More than three dozen specific topics are examined, including biomedical s

  20. Research enrichment: evaluation of structured research in the curriculum for dental medicine students as part of the vertical and horizontal integration of biomedical training and discovery

    Directory of Open Access Journals (Sweden)

    Stewart Tanis

    2008-02-01

    Full Text Available Abstract Background Research programs within medical and dental schools are important vehicles for biomedical and clinical discovery, serving as effective teaching and learning tools by providing situations in which predoctoral students develop problem-solving and critical-thinking skills. Although research programs at many medical and dental schools are well-established, they may not be well integrated into the predoctoral curriculum to effectively support the learning objectives for their students. Methods A series of structured seminars, incorporating faculty research, was designed for first-year dental students at the University of Nevada, Las Vegas, School of Dental Medicine to reinforce and support the concepts and skills taught in concurrent courses. A structured research enrichment period was also created to facilitate student engagement in active research using faculty and student curricular release time. Course evaluations and surveys were administered to gauge student perceptions of the curricular integration of research, the impact of these seminars on recruitment to the research program, and overall levels of student satisfaction with research enrichment. Results The analysis of course surveys revealed that students perceived the research-containing seminars effectively illustrated concepts, were logically sequenced, and were well-integrated into their curriculum. In addition, analysis of surveys revealed that the Integration Seminar courses motivated students to engage in research enrichment. Finally, this analysis provided evidence that students were very satisfied with their overall learning experience during research enrichment. Conclusion Curricular integration is one method of improving the teaching and learning of complicated and inter-related concepts, providing an opportunity to incorporate research training and objectives into traditionally separate didactic courses. Despite the benefits of curricular integration, finding

  1. Potentiometric stripping analysis of zinc and copper in human teeth and dental materials.

    Science.gov (United States)

    Kalicanin, Biljana M; Nikolić, Ruzica S

    2008-01-01

    Potentiometric stripping analysis (PSA) with oxygen as the oxidant has been used to determine soluble zinc and copper levels in exfoliated human teeth (all of which required extraction for orthodontic reasons) and commercial dental materials. The soluble zinc and copper contents of teeth were slightly below the zinc and copper contents in whole teeth reported by other researchers, except in the case of tooth with removed amalgam filling. Soluble zinc and copper concentrations of the dental materials and metal ceramic crowns were 0.50-6.30, and of 2.00-4.30 microg/g, respectively. The results of this work suggest that PSA may be a good method for zinc and copper leaching studies during the investigation of dental prosthetic materials' biocompatibility. Corrosive action of acidic media as evidenced by SEM micrographs caused the leaching of metal ions from teeth.

  2. Bioengineered collagens: emerging directions for biomedical materials.

    Science.gov (United States)

    Ramshaw, John A M; Werkmeister, Jerome A; Dumsday, Geoff J

    2014-01-01

    Mammalian collagen has been widely used as a biomedical material. Nevertheless, there are still concerns about the variability between preparations, particularly with the possibility that the products may transmit animal-based diseases. Many groups have examined the possible application of bioengineered mammalian collagens. However, translating laboratory studies into large-scale manufacturing has often proved difficult, although certain yeast and plant systems seem effective. Production of full-length mammalian collagens, with the required secondary modification to give proline hydroxylation, has proved difficult in E. coli. However, recently, a new group of collagens, which have the characteristic triple helical structure of collagen, has been identified in bacteria. These proteins are stable without the need for hydroxyproline and are able to be produced and purified from E. coli in high yield. Initial studies indicate that they would be suitable for biomedical applications.

  3. Advances in Dental Materials through Nanotechnology: Facts, Perspectives and Toxicological Aspects.

    Science.gov (United States)

    Padovani, Gislaine C; Feitosa, Victor P; Sauro, Salvatore; Tay, Franklin R; Durán, Gabriela; Paula, Amauri J; Durán, Nelson

    2015-11-01

    Nanotechnology is currently driving the dental materials industry to substantial growth, thus reflecting on improvements in materials available for oral prevention and treatment. The present review discusses new developments in nanotechnology applied to dentistry, focusing on the use of nanomaterials for improving the quality of oral care, the perspectives of research in this arena, and discussions on safety concerns regarding the use of dental nanomaterials. Details are provided on the cutting-edge properties (morphological, antibacterial, mechanical, fluorescence, antitumoral, and remineralization and regeneration potential) of polymeric, metallic and inorganic nano-based materials, as well as their use as nanocluster fillers, in nanocomposites, mouthwashes, medicines, and biomimetic dental materials. Nanotoxicological aspects, clinical applications, and perspectives for these nanomaterials are also discussed.

  4. Escherichia coli adhesion, biofilm development and antibiotic susceptibility on biomedical materials.

    Science.gov (United States)

    Gomes, L C; Silva, L N; Simões, M; Melo, L F; Mergulhão, F J

    2015-04-01

    The aim of this work was to test materials typically used in the construction of medical devices regarding their influence in the initial adhesion, biofilm development and antibiotic susceptibility of Escherichia coli biofilms. Adhesion and biofilm development was monitored in 12-well microtiter plates containing coupons of different biomedical materials--silicone (SIL), stainless steel (SS) and polyvinyl chloride (PVC)--and glass (GLA) as control. The susceptibility of biofilms to ciprofloxacin and ampicillin was assessed, and the antibiotic effect in cell morphology was observed by scanning electron microscopy. The surface hydrophobicity of the bacterial strain and materials was also evaluated from contact angle measurements. Surface hydrophobicity was related with initial E. coli adhesion and subsequent biofilm development. Hydrophobic materials, such as SIL, SS, and PVC, showed higher bacterial colonization than the hydrophilic GLA. Silicone was the surface with the greatest number of adhered cells and the biofilms formed on this material were also less susceptible to both antibiotics. It was found that different antibiotics induced different levels of elongation on E. coli sessile cells. Results revealed that, by affecting the initial adhesion, the surface properties of a given material can modulate biofilm buildup and interfere with the outcome of antimicrobial therapy. These findings raise the possibility of fine-tuning surface properties as a strategy to reach higher therapeutic efficacy.

  5. Biopolymers as materials for developing products in pharmaceutical applications and biomedical uses

    Directory of Open Access Journals (Sweden)

    Manuel Guillermo Rojas Cortés

    2010-04-01

    Full Text Available Biopolymers have been widely studied for use in pharmaceutical applications. They have been used for modifying drug release, orientating a drug towards its therapeutic target, penetrating physiological barriers (tissues and cells and protecting unstable therapeutic agents against physiological conditions which are present in a less invasive administration routes. The importance of biopolymers in designing new biomedical devices must thus be stressed, es-pecially when a pharmaceutical substance must be incorporated into a polymer matrix. A new generation of alterna-tives for human health has thus been generated by designing pharmaceutical therapeutic systems in line with the concept of “integrated custom-made product design”. This document reviews the trends concerning using biopoly-mers for designing products having pharmaceutical and biomedical applications. The paper also introduces the elements which should be mastered by engineers for obtaining material which can be used in the health field and tries to provide a reference point regarding the state of the art in this specific field of knowledge.

  6. Effect of surfactant on surface hardness of dental stone and investment casts produced from polyvinyl siloxane duplicating materials.

    Science.gov (United States)

    Al-Johani, Attalah; Clark, Robert K F; Juszczyk, Andrzej S; Radford, David R

    2008-06-01

    Polyvinylsiloxane duplicating materials are typically treated with a topical surfactant before pouring dental models, but the use of topical surfactants in the dental laboratory may affect the surface hardness of the resultant models. The effect of two different topical surfactants on surface hardness of two dental stones (FujiRock and Dentstone) and one phosphate bonded investment material (Croform WB) produced from polyvinyl siloxane (PVS) dental laboratory duplicating moulds was investigated. Topical surfactants affected the surface hardness of FujiRock, Dentstone and Croform WB investment material. Surface hardness of FujiRock increased with Wax-Mate surfactant. However, surface hardness of Croform WB investment material decreased with both topical surfactants.

  7. Mechanical behaviour of dental composite filling materials using digital holography

    OpenAIRE

    Monteiro, J.M.; Lopes, H.; M. A. P. Vaz; Campos, J.C. Reis

    2010-01-01

    One of the most common clinical problems in dentistry is tooth decay. Among the dental filling materials used to repair tooth structure that has been destroyed by decay are dental amalgam and composite materials based on acrylics. Dental amalgam has been used by dentists for the past 150 years as a dental restorative material due to its low cost, ease of application, strength, durability, and bacteriostatic effects. However its safety as a filling material has been questioned due to th...

  8. Joseph F. Keithley Award For Advances in Measurement Science Lecture: Thermophotonic and Photoacoustic Radar Imaging Methods for Biomedical and Dental Imaging

    Science.gov (United States)

    Mandelis, Andreas

    2012-02-01

    In the first part of this presentation I will introduce thermophotonic radar imaging principles and techniques using chirped or binary-phase-coded modulation, methods which can break through the maximum detection depth/depth resolution limitations of conventional photothermal waves. Using matched-filter principles, a methodology enabling parabolic diffusion-wave energy fields to exhibit energy localization akin to propagating hyperbolic wave-fields has been developed. It allows for deconvolution of individual responses of superposed axially discrete sources, opening a new field: depth-resolved thermal coherence tomography. Several examples from dental enamel caries diagnostic imaging to metal subsurface defect thermographic imaging will be discussed. The second part will introduce the field of photoacoustic radar (or sonar) biomedical imaging. I will report the development of a novel biomedical imaging system that utilizes a continuous-wave laser source with a custom intensity modulation pattern, ultrasonic phased array for signal detection and processing coupled with a beamforming algorithm for reconstruction of photoacoustic correlation images. Utilization of specific chirped modulation waveforms (``waveform engineering'') achieves dramatic signal-to-noise-ratio increase and improved axial resolution over pulsed laser photoacoustics. The talk will conclude with aspects of instrumental sensitivity of the PA Radar to optical contrast using cancerous breast tissue-mimicking phantoms, super paramagnetic iron oxide nanoparticles as contrast enhancement agents and in-vivo tissue samples.

  9. Effect of dental restorative materials on total antioxidant capacity and calcium concentration of unstimulated saliva

    Science.gov (United States)

    Moghadam, Mona-Momeni; Garcia-Godoy, Franklin; Asatourian, Armen; Aminsobhani, Mohsen; Scarbecz, Mark; Sheibani, Nader

    2017-01-01

    Background To evaluate the effect of dental amalgam and composite restorations on total antioxidant capacity (TAC) and calcium (Ca) ion concentration of unstimulated saliva. Material and Methods Forty-eight children aged 6-10 years selected and divided into three groups of sixteen (8 males, 8 females). In group A and B, samples consisted of two class II dental composite or amalgam restorations, while in group C samples were caries-free (control group). Unstimulated saliva from all samples was collected and TAC was measured by spectrophotometry using an adaptation of 2, 2’-azino-di-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) assay. The Ca ion level was estimated by an auto- analyzer. Data were analyzed with one- and two-way ANOVA test, at a p<.05 level of significance. Results Composite samples showed significantly higher TAC and lower Ca ion levels compared to amalgam and caries-free samples (p<.05). The TAC values showed only significant difference between groups (p<.05), while the Ca ion results showed significant differences within and between groups (p<.05). Conclusions Dental composite restorations increased TAC and decreased Ca ion levels more than amalgam restorations in saliva. Gender is an effective factor in changes induced in oral cavity as females showed more emphatic reaction to dental filling materials than males. Statement of Clinical Relevance Patients who have dental restorations, especially dental composites, should pay more attention to their dental hygiene, because dental restorations can increase oxidative stress and decrease Ca ion level in saliva, which might jeopardize remineralization process of tooth structures after demineralization. Key words:Amalgam, caries, composite, saliva, total antioxidant capacity. PMID:28149467

  10. Endocrine disruptors and dental materials: health implications associated with their use in Brazil

    Directory of Open Access Journals (Sweden)

    Antonio Jorge Molinário Coelho

    2002-04-01

    Full Text Available This study analyzes international historical trends in the use of different types of materials in dental practice. The author describes the chemical properties of their ingredients and the potential and observed adverse effects in patients and dental technicians resulting from clinical or occupational exposure to various metals like beryllium, used to produce metal alloys. The growing use of various products (resin cements, ionomer cements, aesthetic restorative materials, resins, endodontal cements, and others based on the compound bisphenol-A, whose chemical structure is similar to that of estrogen. Considering the demographic and contemporary work force characteristics of those involved in dental practice in the Brazil, the study highlights the possible effect of the use of these materials in both male and female patients and all age strata, as well as in health professionals with occupational exposure to products containing bisphenol-A.

  11. [Current status and further prospects of dental resin-based materials with antibacterial properties].

    Science.gov (United States)

    Shi, X; Lu, H B; Mao, J; Gong, S Q

    2016-09-01

    The mode of dental antibacterial resin-based materials can be divided into two types, namely, single and combined antibacterial mode. With regard to single antibacterial mode, only one kind of antibacterial agent is added into the resin, which can be released or act as contacting antibacterial agent. The single mode resin has limitation in sterilization methods and effect. As for combined antibacterial mode, it is a combination of different types of biocides and thus maximizes the sterilizing effect, including the releasing antibacterial agent incorporated with the contacting antibacterial agent or antibacterial agents combined with calcium compound possessing biological mineralization function. In this paper, current status and further prospects of dental resin-based materials with antibacterial properties are reviewed from the perspectives of single and combined antibacterial modes to provide guidance for dental antibacterial resin material research.

  12. Materials for endosseous dental implants.

    Science.gov (United States)

    Wataha, J C

    1996-02-01

    The goal of placement of endosseous dental implants is to achieve osseointegration or biointegration of the bone with the implant. A wide variety of materials has been used for these implants, but only a few promote osseointegration and biointegration. Titanium and titanium alloy (Ti6A14V) have been the most widely used of these materials. The surface oxide of titanium appears to be central to the ability of this material to osseointegrate. The oxide limits dissolution of elements and promotes the deposition of biological molecules which allow bone to exist as close as 30 A to the surface of the implant. The details of the ultrastructure of the gap between the implant and bone remain undefined, and the consequences of elements which are released on the interface over time are not known. These areas of investigation are particularly important in defining the differences between commercially pure titanium implants and those made of titanium, aluminium and vanadium. The epithelial interface between the gingiva and titanium appears to contain many of the structural characteristics of the native tooth-gingiva interface, but details are still vague. The connective tissue interface with the titanium appears to be one of tightly fitting tissues rather than adhesion. Ceramic coatings appear to improve the ingrowth of bone and promote chemical integration of the implant with the bone. The characteristics of these coatings are complex and affect the bony response, but the mechanisms remain obscure. The degradation of the coatings is an issue of particular controversy. Progress in dental implantology is likely to continue as the interface between the material and bone is more clearly understood, and biological molecules and artificial tissues are developed.

  13. Biofilm formation on dental restorative and implant materials.

    Science.gov (United States)

    Busscher, H J; Rinastiti, M; Siswomihardjo, W; van der Mei, H C

    2010-07-01

    Biomaterials for the restoration of oral function are prone to biofilm formation, affecting oral health. Oral bacteria adhere to hydrophobic and hydrophilic surfaces, but due to fluctuating shear, little biofilm accumulates on hydrophobic surfaces in vivo. More biofilm accumulates on rough than on smooth surfaces. Oral biofilms mostly consist of multiple bacterial strains, but Candida species are found on acrylic dentures. Biofilms on gold and amalgam in vivo are thick and fully covering, but barely viable. Biofilms on ceramics are thin and highly viable. Biofilms on composites and glass-ionomer cements cause surface deterioration, which enhances biofilm formation again. Residual monomer release from composites influences biofilm growth in vitro, but effects in vivo are less pronounced, probably due to the large volume of saliva into which compounds are released and its continuous refreshment. Similarly, conflicting results have been reported on effects of fluoride release from glass-ionomer cements. Finally, biomaterial-associated infection of implants and devices elsewhere in the body is compared with oral biofilm formation. Biomaterial modifications to discourage biofilm formation on implants and devices are critically discussed for possible applications in dentistry. It is concluded that, for dental applications, antimicrobial coatings killing bacteria upon contact are more promising than antimicrobial-releasing coatings.

  14. Gold and palladium burden from dental restoration materials.

    Science.gov (United States)

    Drasch, G; Muss, C; Roider, G

    2000-06-01

    From 81 volunteers (16 without dental restorations, 65 with gold crowns or inlays) samples of saliva before and after chewing gum, blood, serum, urine and faeces were taken and analysed for gold (Au) and palladium (Pd). The Au concentration in all analysed biomonitors correlates significantly to the number of teeth with gold restorations. For Pd the correlations were still significant, but weaker than for Au. Persons with gold restorations show maximal Au and Pd concentrations, 10(2)-10(3) higher than the background burden. The calculated maximal daily Au load in saliva (1.38 mg Au per day) reaches the range of an oral Au therapy for rheumatoid arthritis with 6 mg Auranofin (= 1.74 mg Au per day). During this therapy severe and frequent side effects are reported. In contrast, the Au concentration in serum maximally reached from Au restorations, amounts to only approximately 1/20 of the Au level during arthritis therapy. But even under subtherapeutic doses of 1 mg Auranofin/day severe side effects have been reported (4 out of 56 cases). The mean Au blood concentration from 1 mg Auranofin daily was only 3 times higher than our maximum value. A toxicological classification of the Pd values is difficult, because no toxicological threshold limit has been established, especially for the low-level long-term burden with Pd.

  15. Do Dental Resin Composites Accumulate More Oral Biofilms and Plaque than Amalgam and Glass Ionomer Materials?

    Directory of Open Access Journals (Sweden)

    Ning Zhang

    2016-11-01

    Full Text Available A long-time drawback of dental composites is that they accumulate more biofilms and plaques than amalgam and glass ionomer restorative materials. It would be highly desirable to develop a new composite with reduced biofilm growth, while avoiding the non-esthetics of amalgam and low strength of glass ionomer. The objectives of this study were to: (1 develop a protein-repellent composite with reduced biofilms matching amalgam and glass ionomer for the first time; and (2 investigate their protein adsorption, biofilms, and mechanical properties. Five materials were tested: A new composite containing 3% of protein-repellent 2-methacryloyloxyethyl phosphorylcholine (MPC; the composite with 0% MPC as control; commercial composite control; dental amalgam; resin-modified glass ionomer (RMGI. A dental plaque microcosm biofilm model with human saliva as inoculum was used to investigate metabolic activity, colony-forming units (CFU, and lactic acid production. Composite with 3% MPC had flexural strength similar to those with 0% MPC and commercial composite control (p > 0.1, and much greater than RMGI (p < 0.05. Composite with 3% MPC had protein adsorption that was only 1/10 that of control composites (p < 0.05. Composite with 3% MPC had biofilm CFU and lactic acid much lower than control composites (p < 0.05. Biofilm growth, metabolic activity and lactic acid on the new composite with 3% MPC were reduced to the low level of amalgam and RMGI (p > 0.1. In conclusion, a new protein-repellent dental resin composite reduced oral biofilm growth and acid production to the low levels of non-esthetic amalgam and RMGI for the first time. The long-held conclusion that dental composites accumulate more biofilms than amalgam and glass ionomer is no longer true. The novel composite is promising to finally overcome the major biofilm-accumulation drawback of dental composites in order to reduce biofilm acids and secondary caries.

  16. Nano-sized aerosol classification, collection and analysis--method development using dental composite materials.

    Science.gov (United States)

    Bogdan, Axel; Buckett, Mary I; Japuntich, Daniel A

    2014-01-01

    This article presents a methodical approach for generating, collecting, and analyzing nano-size (1-100 nm) aerosol from abraded dental composite materials. Existing aerosol sampling instruments were combined with a custom-made sampling chamber to create and sample a fresh, steady-state aerosol size distribution before significant Brownian coagulation. Morphological, size, and compositional information was obtained by Transmission Electron Microscopy (TEM). To create samples sizes suitable for TEM analysis, aerosol concentrations in the test chamber had to be much higher than one would typically expect in a dental office, and therefore, these results do not represent patient or dental personnel exposures. Results show that nano-size aerosol was produced by the dental drill alone, with and without cooling water drip, prior to abrasion of dental composite. During abrasion, aerosol generation seemed independent of the percent filler load of the restorative material and the operator who generated the test aerosol. TEM investigation showed that "chunks" of filler and resin were generated in the nano-size range; however, free nano-size filler particles were not observed. The majority of observed particles consisted of oil droplets, ash, and graphitic structures.

  17. Roughness Measurement of Dental Materials

    Science.gov (United States)

    Shulev, Assen; Roussev, Ilia; Karpuzov, Simeon; Stoilov, Georgi; Ignatova, Detelina; See, Constantin von; Mitov, Gergo

    2016-06-01

    This paper presents a roughness measurement of zirconia ceramics, widely used for dental applications. Surface roughness variations caused by the most commonly used dental instruments for intraoral grinding and polishing are estimated. The applied technique is simple and utilizes the speckle properties of the scattered laser light. It could be easily implemented even in dental clinic environment. The main criteria for roughness estimation is the average speckle size, which varies with the roughness of zirconia. The algorithm used for the speckle size estimation is based on the normalized autocorrelation approach.

  18. Roughness Measurement of Dental Materials

    Directory of Open Access Journals (Sweden)

    Shulev Assen

    2016-06-01

    Full Text Available This paper presents a roughness measurement of zirconia ceramics, widely used for dental applications. Surface roughness variations caused by the most commonly used dental instruments for intraoral grinding and polishing are estimated. The applied technique is simple and utilizes the speckle properties of the scattered laser light. It could be easily implemented even in dental clinic environment. The main criteria for roughness estimation is the average speckle size, which varies with the roughness of zirconia. The algorithm used for the speckle size estimation is based on the normalized autocorrelation approach.

  19. Characterization of the surface of protein-adsorbed dental materials by wetting and streaming potential measurements

    NARCIS (Netherlands)

    Matsumura, H.; Kawasaki, K.; Okumura, N.; Kambara, M.; Norde, W.

    2003-01-01

    In this study we have elucidated the water-wettability and the electrokinetic surface potential of protein-covered dental materials. The proteins used here as typical proteins were human serum albumin and lysozyme from hen*s egg. The wettability (hydrophobicity/hydrophilicity) and the surface potent

  20. Characterization of the surface of protein-adsorbed dental materials by wetting and streaming potential measurements

    NARCIS (Netherlands)

    Matsumura, H; Kawasaki, K; Okumura, N; Kambara, M; Norde, W

    2003-01-01

    In this study we have elucidated the water-wettability and the electrokinetic surface potential of protein-covered dental materials. The proteins used here as typical proteins were human serum albumin and lysozyme from hen's egg. The wettability (hydrophobicity/hydrophilicity) and the surface potent

  1. Collaborative Relationships in Dental Materials Research: Measuring the Volume and Outcomes.

    Science.gov (United States)

    Garrison, Howard H.; And Others

    1992-01-01

    Collaborative relationships between researchers and resources from government, industry, and academia were studied through a survey of research into dental materials. The outcomes of research conducted under various arrangements by 386 targeted respondents were reviewed. Implications of the high rate of collaboration for both industry and academia…

  2. Special cluster issue on tribocorrosion of dental materials

    Science.gov (United States)

    Mathew, Mathew T.; Stack, Margaret M.

    2013-10-01

    Tribocorrosion affects all walks of life from oil and gas conversion to biomedical materials. Wear can interact with corrosion to enhance it or impede it; conversely, corrosion can enhance or impede wear. The understanding of the interactions between physical and chemical phenomena has been greatly assisted by electrochemical and microscopic techniques. In dentistry, it is well recognized that erosion due to dissolution (a term physicists use to denote wear) of enamel can result in tooth decay; however, the effects of the oral environment, i.e. pH levels, electrochemical potential and any interactions due to the forces involved in chewing are not well understood. This special cluster issue includes investigations on the fundamentals of wear-corrosion interactions involved in simulated oral environments, including candidate dental implant and veneer materials. The issue commences with a fundamental study of titanium implants and this is followed by an analysis of the behaviour of commonly used temporomandibular devices in a synovial fluid-like environment. The analysis of tribocorrosion mechanisms of Ti6Al4V biomedical alloys in artificial saliva with different pHs is addressed and is followed by a paper on fretting wear, on hydroxyapatite-titanium composites in simulated body fluid, supplemented with protein (bovine serum albumin). The effects of acid treatments on tooth enamel, and as a surface engineering technique for dental implants, are investigated in two further contributions. An analysis of the physiological parameters of intraoral wear is addressed; this is followed by a study of candidate dental materials in common beverages such as tea and coffee with varying acidity and viscosity and the use of wear maps to identify the safety zones for prediction of material degradation in such conditions. Hence, the special cluster issue consists of a range of tribocorrosion contributions involving many aspects of dental tribocorrosion, from analysis of physiological

  3. Reaching Consensus on Essential Biomedical Science Learning Objectives in a Dental Curriculum.

    Science.gov (United States)

    Best, Leandra; Walton, Joanne N; Walker, Judith; von Bergmann, HsingChi

    2016-04-01

    This article describes how the University of British Columbia Faculty of Dentistry reached consensus on essential basic biomedical science objectives for DMD students and applied the information to the renewal of its DMD curriculum. The Delphi Method was used to build consensus among dental faculty members and students regarding the relevance of over 1,500 existing biomedical science objectives. Volunteer panels of at least three faculty members (a basic scientist, a general dentist, and a dental specialist) and a fourth-year dental student were formed for each of 13 biomedical courses in the first two years of the program. Panel members worked independently and anonymously, rating each course objective as "need to know," "nice to know," "irrelevant," or "don't know." Panel members were advised after each round which objectives had not yet achieved a 75% consensus and were asked to reconsider their ratings. After a maximum of three rounds to reach consensus, a second group of faculty experts reviewed and refined the results to establish the biomedical science objectives for the renewed curriculum. There was consensus on 46% of the learning objectives after round one, 80% after round two, and 95% after round three. The second expert group addressed any remaining objectives as part of its review process. Only 47% of previous biomedical science course objectives were judged to be essential or "need to know" for the general dentist. The consensus reached by participants in the Delphi Method panels and a second group of faculty experts led to a streamlined, better integrated DMD curriculum to prepare graduates for future practice.

  4. Recent Advances in Food-Packing, Pharmaceutical and Biomedical Applications of Zein and Zein-Based Materials

    Directory of Open Access Journals (Sweden)

    Elisângela Corradini

    2014-12-01

    Full Text Available Zein is a biodegradable and biocompatible material extracted from renewable resources; it comprises almost 80% of the whole protein content in corn. This review highlights and describes some zein and zein-based materials, focusing on biomedical applications. It was demonstrated in this review that the biodegradation and biocompatibility of zein are key parameters for its uses in the food-packing, biomedical and pharmaceutical fields. Furthermore, it was pointed out that the presence of hydrophilic-hydrophobic groups in zein chains is a very important aspect for obtaining material with different hydrophobicities by mixing with other moieties (polymeric or not, but also for obtaining derivatives with different properties. The physical and chemical characteristics and special structure (at the molecular, nano and micro scales make zein molecules inherently superior to many other polymers from natural sources and synthetic ones. The film-forming property of zein and zein-based materials is important for several applications. The good electrospinnability of zein is important for producing zein and zein-based nanofibers for applications in tissue engineering and drug delivery. The use of zein’s hydrolysate peptides for reducing blood pressure is another important issue related to the application of derivatives of zein in the biomedical field. It is pointed out that the biodegradability and biocompatibility of zein and other inherent properties associated with zein’s structure allow a myriad of applications of such materials with great potential in the near future.

  5. Recent advances in food-packing, pharmaceutical and biomedical applications of zein and zein-based materials.

    Science.gov (United States)

    Corradini, Elisângela; Curti, Priscila S; Meniqueti, Adriano B; Martins, Alessandro F; Rubira, Adley F; Muniz, Edvani Curti

    2014-12-04

    Zein is a biodegradable and biocompatible material extracted from renewable resources; it comprises almost 80% of the whole protein content in corn. This review highlights and describes some zein and zein-based materials, focusing on biomedical applications. It was demonstrated in this review that the biodegradation and biocompatibility of zein are key parameters for its uses in the food-packing, biomedical and pharmaceutical fields. Furthermore, it was pointed out that the presence of hydrophilic-hydrophobic groups in zein chains is a very important aspect for obtaining material with different hydrophobicities by mixing with other moieties (polymeric or not), but also for obtaining derivatives with different properties. The physical and chemical characteristics and special structure (at the molecular, nano and micro scales) make zein molecules inherently superior to many other polymers from natural sources and synthetic ones. The film-forming property of zein and zein-based materials is important for several applications. The good electrospinnability of zein is important for producing zein and zein-based nanofibers for applications in tissue engineering and drug delivery. The use of zein's hydrolysate peptides for reducing blood pressure is another important issue related to the application of derivatives of zein in the biomedical field. It is pointed out that the biodegradability and biocompatibility of zein and other inherent properties associated with zein's structure allow a myriad of applications of such materials with great potential in the near future.

  6. Investigation of contact allergy to dental materials by patch testing

    Directory of Open Access Journals (Sweden)

    Reena Rai

    2014-01-01

    Full Text Available Background: Dental products are widely used by patients and dental personnel alike and may cause problems for both. Dental materials could cause contact allergy with varying manifestations such as burning, pain, stomatitis, cheilitis, ulcers, lichenoid reactions localized to the oral mucosa in patients, and hand dermatitis in dental personnel. Patch testing with the dental series comprising commonly used materials can be used to detect contact allergies to dental materials. Aim: This study aimed to identify contact allergy among patients who have oral mucosal lesions after dental treatment and among dental personnel who came in contact with these materials. Materials and Methods: Twenty patients who had undergone dental procedures with symptoms of oral lichen planus, oral stomatitis, burning mouth, and recurrent aphthosis, were included in the study. Dental personnel with history of hand dermatitis were also included in the study. Patch testing was performed using Chemotechnique Dental Series and results interpreted as recommended by the International Contact Dermatitis Research Group (ICDRG. Results: Out of 13 patients who had undergone dental treatment/with oral symptoms, six patients with stomatitis, lichenoid lesions, and oral ulcers showed positive patch tests to a variety of dental materials, seven patients with ulcers had negative patch tests, seven dental personnel with hand dermatitis showed multiple allergies to various dental materials, and most had multiple positivities. Conclusion: The patch test is a useful, simple, noninvasive method to detect contact allergies among patients and among dental personnel dealing with these products. Long term studies are necessary to establish the relevance of these positive patch tests by eliminating the allergic substances, identifying clinical improvement, and substituting with nonallergenic materials.

  7. Occupational exposure to contaminated biological material: perceptions and feelings experienced among dental students

    Directory of Open Access Journals (Sweden)

    Camila PINELLI

    Full Text Available INTRODUCTION: Dental students may be a particularly vulnerable group exposed to the risk of acquiring infections through occupational injuries.OBJECTIVE: To investigate the perceptions with regard to their occupational exposure to potentially infectious biologic materials.MATERIAL AND METHOD: Interviews were conducted by means of a script with open questions. The speeches were recorded, transcribed and qualitative analysis was performed with the aid of QUALIQUANTISOFT® software. The Collective Subject Discourse (CSD was obtained.RESULT: The feeling most frequently experienced was related to the fear of contagion. Most accidents occurred during the handling of sharp dental instruments. Respondents attributed the occurrence of accidents especially the lack of attention, carelessness while handling sharp instruments, and lack of use of Personal Protective Equipment. As regards the measures taken right after the exposure, they "washed the local area". Other respondents reported they "continued the dental treatment". They complained mostly about the fear of having been infected, and because they had to leave the faculty to take blood exams for HIV screening. As part of the learning experience the injured reported they paid more attention when handling sharp instruments. The students informed that any type of injury due to contact with contaminated material must be notified. However, they were neglectful about reporting their own injury.CONCLUSION: Education strategies for preventive measures related to occupational exposure must be restructured, because the knowledge and the fear of contagion among dental students were not always sufficient for a complete adherence to treatment protocols and notification.

  8. DEVELOPMENT AND VERIFICATION OF NEW SOLID DENTAL FILLING TEMPORARY MATERIALS CONTAINING ZINC. FORMULA DEVELOPMENT STAGE.

    Science.gov (United States)

    Pytko-Polończyk, Jolanta; Antosik, Agata; Zajac, Magdalena; Szlósarczyk, Marek; Krywult, Agnieszka; Jachowicz, Renata; Opoka, Włodzimierz

    2016-01-01

    Caries is the most popular problem affecting teeth and this is the reason why so many temporary dental filling materials are being developed. An example of such filling is zinc oxide paste mixed with eugenol, Thymodentin and Coltosol F®. Zinc-oxide eugenol is used in dentistry because of its multiplied values: it improves heeling of the pulp by dentine bridge formation; has antiseptic properties; is hygroscopic. Because of these advantages compouds of zinc oxide are used as temporary fillings, especially in deep caries lesions when treatment is oriented on support of vital pulp. Temporary dental fillings based on zinc oxide are prepared ex tempone by simple mixing powder (Thymodentin) and eugenol liqiud together or a ready to use paste Coltosol F®. Quantitative composition depends mainly on experience of person who is preparing it, therefore, exact qualitative composition of dental fillings is not replicable. The main goal of the study was to develop appropriate dental fillings in solid form containing set amount of zinc oxide. Within the study, the influence of preparation method on solid dental fillings properties like mechanical properties and zinc ions release were examined.

  9. Advanced materials for aerospace and biomedical applications: New glasses for hermetic titanium seals

    Energy Technology Data Exchange (ETDEWEB)

    Brow, R.K.; Tallant, D.R.; Crowder, S.V. [and others

    1996-11-01

    Titanium and titanium alloys have an outstanding strength-to-weight ratio and corrosion resistance and so are materials of choice for a variety of aerospace and biomedical applications. Such applications are limited by the lack of a viable hermetic glass sealing technology. Conventional silicate sealing glasses are readily reduced by titanium to form interfacial silicides that are incompatible with a robust glass/metal seal. Borate-based glasses undergo a similar thermochemistry and are reduced to a titanium boride. The kinetics of this reactions, however, are apparently slower and so a deleterious interface does not form. Chemically durable lanthanoborate glasses were examined as candidate sealing compositions. The compositions, properties, and structures of several alkaline earth, alumina, and titania lanthanoborate glass forming systems were evaluated and this information was used as the basis for a designed experiment to optimize compositions for Ti-sealing. A number of viable compositions were identified and sealing procedures established. Finally, glass formation, properties, and structure of biocompatible Fe{sub 2}O{sub 3}- and TiO{sub 2}-doped calcium phosphate systems were also evaluated.

  10. AN INVESTIGATION ON SOFT MAGNETIC AND NON-MAGNETIC MATERIALS UNDER LOW FREQUENCY FOR BIOMEDICAL SENSOR APPLICATION

    Directory of Open Access Journals (Sweden)

    Sheroz Khan

    2012-02-01

    Full Text Available In consequence of the recent development of magnetic sensors in biomedical sector, the investigation of magneticmaterials has been a contributing factor in application stage. This paper proposes a novel technique to investigate materials by obtaining unique distinctive impedance peaks with unique impedance values. A magneto-inductive sensoris used to measure the induction of magnetic and non-magnetic impedance peaks related to the change in permeability, thus characterizing the materials under low frequency.

  11. Priorities for future innovation, research, and advocacy in dental restorative materials.

    Science.gov (United States)

    Watson, T; Fox, C H; Rekow, E D

    2013-11-01

    Innovations in materials science, both within and outside of dentistry, open opportunities for the development of exciting direct restorative materials. From rich dialog among experts from dental and non-dental academic institutions and industry, as well as those from policy, research funding, and professional organizations, we learned that capitalizing on these opportunities is multifactorial and far from straightforward. Beginning from the point when a restoration is needed, what materials, delivery systems, and skills are needed to best serve the most people throughout the world's widely varied economic and infrastructure systems? New research is a critical element in progress. Effective advocacy can influence funding and drives change in practice and policy. Here we articulate both research and advocacy priorities, with the intention of focusing the energy and expertise of our best scientists on making a difference, bringing new innovations to improve oral health.

  12. An evaluation of dental operative simulation materials.

    Science.gov (United States)

    He, Li-Hong; Foster Page, Lyndie; Purton, David

    2012-01-01

    The study was to evaluate the performance of different materials used in dental operative simulation and compare them with those of natural teeth. Three typical phantom teeth materials were compared with extracted permanent teeth by a nanoindentation system and evaluated by students and registered dentists on the drilling sensation of the materials. Moreover, the tool life (machinability) of new cylindrical diamond burs on cutting the sample materials was tested and the burs were observed. Although student and dentist evaluations were scattered and inconclusive, it was found that elastic modulus (E) and hardness (H) were not the main factors in determining the drilling sensation of the materials. The sensation of drilling is a reflection of cutting force and power consumption.An ideal material for dental simulation should be able to generate similar drilling resistance to that of natural tooth, which is the machinability of the material.

  13. LC Packing Materials for Pharmaceutical and Biomedical Analysis%用于药学和生物医学分析的液相色谱填料

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The author has prepared novel liquid chromatography (LC) packing materials for pharmaceutical and biomedical analysis. Those include LC packing materials for direct serum injection assays of drugs and their metabolites, LC packing materials for resolution of enantiomeric drugs, and uniformly sized molecularly imprinted polymers for drugs and their metabolites. This review article deals with the preparation of these materials and the pharmaceutical and biomedical applications of them in recognition of The Society of Chromatographic Sciences Award.

  14. Color measurement of teeth and dental materials using a fiberoptic probe

    Science.gov (United States)

    Melnik, Ivan S.; Rawicz, Andrew H.; Dets, Sergiy M.

    1998-04-01

    Assessment of tooth color by visual evaluation is a complex task. A number of attempts to build a reliable instrument that can measure the color of teeth have been undertaken in the last 15 years. These attempts were aimed at using conventional colorimeters designed for color measurement of oblique objects. However, the translucency of teeth strongly affected the colorimeters' readout because of the size of the measuring aperture and the geometry of the spectroscope. Here we present the results of our spectroscopic study of dental materials and human teeth that show a characteristic behavior of optical spectra collected with a fiberoptic probe. The probe consisted of 300 micrometer irradiating and 1 mm detecting fibers that were coupled to a white light source (color temperature 6500 K) and to a spectroscope. The conventional shades from Vita and Chromascop shade guides were measured with different location of the fibers. The color of the dental shades was measured by a standard spectrophotometer with two different apertures. We found that registered spectra depended on fiber position and color coordinates changed with aperture size. The influence of the fiber positioning was approved with color measurement of vital teeth. A simplified colorimetric system based on two color coordinates, lightness L*, and the difference, (a* - b*), has been proposed. Finally, we describe a novel dental color matching device based on a fiberoptic probe. The device is able to classify all dental shades from Vita, Chromascop, and Bioform shade guides and is aimed at better color matching of restorative materials to native teeth.

  15. Microstructure and mechanical behavior of metal injection molded Ti-Nb binary alloys as biomedical material.

    Science.gov (United States)

    Zhao, Dapeng; Chang, Keke; Ebel, Thomas; Qian, Ma; Willumeit, Regine; Yan, Ming; Pyczak, Florian

    2013-12-01

    The application of titanium (Ti) based biomedical materials which are widely used at present, such as commercially pure titanium (CP-Ti) and Ti-6Al-4V, are limited by the mismatch of Young's modulus between the implant and the bones, the high costs of products, and the difficulty of producing complex shapes of materials by conventional methods. Niobium (Nb) is a non-toxic element with strong β stabilizing effect in Ti alloys, which makes Ti-Nb based alloys attractive for implant application. Metal injection molding (MIM) is a cost-efficient near-net shape process. Thus, it attracts growing interest for the processing of Ti and Ti alloys as biomaterial. In this investigation, metal injection molding was applied to the fabrication of a series of Ti-Nb binary alloys with niobium content ranging from 10wt% to 22wt%, and CP-Ti for comparison. Specimens were characterized by melt extraction, optical microscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and transmission electron microscopy (TEM). Titanium carbide formation was observed in all the as-sintered Ti-Nb binary alloys but not in the as-sintered CP-Ti. Selected area electron diffraction (SAED) patterns revealed that the carbides are Ti2C. It was found that with increasing niobium content from 0% to 22%, the porosity increased from about 1.6% to 5.8%, and the carbide area fraction increased from 0% to about 1.8% in the as-sintered samples. The effects of niobium content, porosity and titanium carbides on mechanical properties have been discussed. The as-sintered Ti-Nb specimens exhibited an excellent combination of high tensile strength and low Young's modulus, but relatively low ductility.

  16. Trends in biomedical engineering: focus on Smart Bio-Materials and Drug Delivery.

    Science.gov (United States)

    Tanzi, Maria Cristina; Bozzini, Sabrina; Candiani, Gabriele; Cigada, Alberto; De Nardo, Luigi; Farè, Silvia; Ganazzoli, Fabio; Gastaldi, Dario; Levi, Marinella; Metrangolo, Pierangelo; Migliavacca, Francesco; Osellame, Roberto; Petrini, Paola; Raffaini, Giuseppina; Resnati, Giuseppe; Vena, Pasquale; Vesentini, Simone; Zunino, Paolo

    2011-01-01

    The present article reviews on different research lines, namely: drug and gene delivery, surface modification/modeling, design of advanced materials (shape memory polymers and biodegradable stents), presently developed at Politecnico di Milano, Italy. For gene delivery, non-viral polycationic-branched polyethylenimine (b-PEI) polyplexes are coated with pectin, an anionic polysaccharide, to enhance the polyplex stability and decrease b-PEI cytotoxicity. Perfluorinated materials, specifically perfluoroether, and perfluoro-polyether fluids are proposed as ultrasound contrast agents and smart agents for drug delivery. Non-fouling, self-assembled PEG-based monolayers are developed on titanium surfaces with the aim of drastically reducing cariogenic bacteria adhesion on dental implants. Femtosecond laser microfabrication is used for selectively and spatially tuning the wettability of polymeric biomaterials and the effects of femtosecond laser ablation on the surface properties of polymethylmethacrylate are studied. Innovative functionally graded Alumina-Ti coatings for wear resistant articulating surfaces are deposited with PLD and characterized by means of a combined experimental and computational approach. Protein adsorption on biomaterials surfaces with an unlike wettability and surface-modification induced by pre-adsorbed proteins are studied by atomistic computer simulations. A study was performed on the fabrication of porous Shape Memory Polymeric structures and on the assessment of their potential application in minimally invasive surgical procedures. A model of magnesium (alloys) degradation, in a finite element framework analysis, and a bottom-up multiscale analysis for modeling the degradation mechanism of PLA matrices was developed, with the aim of providing valuable tools for the design of bioresorbable stents.

  17. Multiaxial analysis of dental composite materials.

    Science.gov (United States)

    Kotche, Miiri; Drummond, James L; Sun, Kang; Vural, Murat; DeCarlo, Francesco

    2009-02-01

    Dental composites are subjected to extreme chemical and mechanical conditions in the oral environment, contributing to the degradation and ultimate failure of the material in vivo. The objective of this study is to validate an alternative method of mechanically loading dental composite materials. Confined compression testing more closely represents the complex loading that dental restorations experience in the oral cavity. Dental composites, a nanofilled and a hybrid microfilled, were prepared as cylindrical specimens, light-cured in ring molds of 6061 aluminum, with the ends polished to ensure parallel surfaces. The samples were subjected to confined compression loading to 3, 6, 9, 12, and 15% axial strain. Upon loading, the ring constrains radial expansion of the specimen, generating confinement stresses. A strain gage placed on the outer wall of the aluminum confining ring records hoop strain. Assuming plane stress conditions, the confining stress (sigma(c)) can be calculated at the sample/ring interface. Following mechanical loading, tomographic data was generated using a high-resolution microtomography system developed at beamline 2-BM of the Advanced Photon Source at Argonne National Laboratory. Extraction of the crack and void surfaces present in the material bulk is numerically represented as crack edge/volume (CE/V), and calculated as a fraction of total specimen volume. Initial results indicate that as the strain level increases the CE/V increases. Analysis of the composite specimens under different mechanical loads suggests that microtomography is a useful tool for three-dimensional evaluation of dental composite fracture surfaces.

  18. Minimum requirements for new dental materials.

    Science.gov (United States)

    Mjör, I A

    2007-12-01

    A brief review of the development of standards for testing and certification of dental materials is presented. The tests employed in the standards are not correlated for the clinical use of the materials, nor to the reasons for failures of the materials. They are, therefore, of limited value for the selection of materials to be used in practice but they are important for quality control of the manufacture of the materials. Previous certification programmes are being discontinued. The responsibility for selecting safe and efficient materials is transferred to the clinicians whereas making safe and efficient materials still is the responsibility of the manufacturers.

  19. Students' perceptions of materials and techniques used at European dental schools in the education of fixed prosthodontics

    NARCIS (Netherlands)

    Brand, H.S.; Kamell, H.; Kharbanda, A.; Dozic, A.

    2013-01-01

    The aim of this study was to explore the materials and procedures used by students in dental schools across Europe for teaching fixed prosthodontics. An online questionnaire, containing twenty-eight dichotomous, multiple-choice, and Likert scale rating questions, was sent to students in forty dental

  20. Fifty years of Brazilian Dental Materials Group: scientific contributions of dental materials field evaluated by systematic review

    Science.gov (United States)

    ROSA, Wellington Luiz de Oliveira; SILVA, Tiago Machado; LIMA, Giana da Silveira; SILVA, Adriana Fernandes; PIVA, Evandro

    2016-01-01

    ABSTRACT Objective A systematic review was conducted to analyze Brazilian scientific and technological production related to the dental materials field over the past 50 years. Material and Methods This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (Prisma) statement. Searches were performed until December 2014 in six databases: MedLine (PubMed), Scopus, LILACS, IBECS, BBO, and the Cochrane Library. Additionally, the Brazilian patent database (INPI - Instituto Nacional de Propriedade Industrial) was screened in order to get an overview of Brazilian technological development in the dental materials field. Two reviewers independently analyzed the documents. Only studies and patents related to dental materials were included in this review. Data regarding the material category, dental specialty, number of documents and patents, filiation countries, and the number of citations were tabulated and analyzed in Microsoft Office Excel (Microsoft Corporation, Redmond, Washington, United States). Results A total of 115,806 studies and 53 patents were related to dental materials and were included in this review. Brazil had 8% affiliation in studies related to dental materials, and the majority of the papers published were related to dental implants (1,137 papers), synthetic resins (681 papers), dental cements (440 papers), dental alloys (392 papers) and dental adhesives (361 papers). The Brazilian technological development with patented dental materials was smaller than the scientific production. The most patented type of material was dental alloys (11 patents), followed by dental implants (8 patents) and composite resins (7 patents). Conclusions Dental materials science has had a substantial number of records, demonstrating an important presence in scientific and technological development of dentistry. In addition, it is important to approximate the relationship between academia and industry to expand the technological development in

  1. Fifty years of Brazilian Dental Materials Group: scientific contributions of dental materials field evaluated by systematic review

    Directory of Open Access Journals (Sweden)

    Wellington Luiz de Oliveira ROSA

    Full Text Available ABSTRACT Objective A systematic review was conducted to analyze Brazilian scientific and technological production related to the dental materials field over the past 50 years. Material and Methods This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (Prisma statement. Searches were performed until December 2014 in six databases: MedLine (PubMed, Scopus, LILACS, IBECS, BBO, and the Cochrane Library. Additionally, the Brazilian patent database (INPI - Instituto Nacional de Propriedade Industrial was screened in order to get an overview of Brazilian technological development in the dental materials field. Two reviewers independently analyzed the documents. Only studies and patents related to dental materials were included in this review. Data regarding the material category, dental specialty, number of documents and patents, filiation countries, and the number of citations were tabulated and analyzed in Microsoft Office Excel (Microsoft Corporation, Redmond, Washington, United States. Results A total of 115,806 studies and 53 patents were related to dental materials and were included in this review. Brazil had 8% affiliation in studies related to dental materials, and the majority of the papers published were related to dental implants (1,137 papers, synthetic resins (681 papers, dental cements (440 papers, dental alloys (392 papers and dental adhesives (361 papers. The Brazilian technological development with patented dental materials was smaller than the scientific production. The most patented type of material was dental alloys (11 patents, followed by dental implants (8 patents and composite resins (7 patents. Conclusions Dental materials science has had a substantial number of records, demonstrating an important presence in scientific and technological development of dentistry. In addition, it is important to approximate the relationship between academia and industry to expand the technological development

  2. Synthesis, characterization and antibacterial activity of copper, nickel and bimetallic Cu-Ni nanoparticles for potential use in dental materials

    Institute of Scientific and Technical Information of China (English)

    Liliana Argueta-Figueroa; Raúl A. Morales-Luckie; Rogelio J. Scougall-Vilchis; Oscar F. Olea-Mejía

    2014-01-01

    The antibacterial effect is a desirable property in dental materials. Development of simple methods for the preparation of nanosized metal particles has attracted significant attention because of their future applications due to unusual size-dependent antibacterial properties. Copper (Cu), Nickel (Ni) and bimetallic Cu-Ni nanoparticles were prepared by a simple chemical method and their antibacterial activity was tested against the widely used standard human pathogens Staphylococcus aureus (gram-negative) and Escherichia coli (gram-positive). Additionally, these nanoparticles were tested against the dental pathogen Streptococcus mutans. Our results are promising for potential use in dental materials science.

  3. Synthesis, characterization and antibacterial activity of copper, nickel and bimetallic Cu–Ni nanoparticles for potential use in dental materials

    Directory of Open Access Journals (Sweden)

    Liliana Argueta-Figueroa

    2014-08-01

    Full Text Available The antibacterial effect is a desirable property in dental materials. Development of simple methods for the preparation of nanosized metal particles has attracted significant attention because of their future applications due to unusual size-dependent antibacterial properties. Copper (Cu, Nickel (Ni and bimetallic Cu–Ni nanoparticles were prepared by a simple chemical method and their antibacterial activity was tested against the widely used standard human pathogens Staphylococcus aureus (gram-negative and Escherichia coli (gram-positive. Additionally, these nanoparticles were tested against the dental pathogen Streptococcus mutans. Our results are promising for potential use in dental materials science.

  4. Silk fibroin nanostructured materials for biomedical applications

    Science.gov (United States)

    Mitropoulos, Alexander N.

    Nanostructured biopolymers have proven to be promising to develop novel biomedical applications where forming structures at the nanoscale normally occurs by self-assembly. However, synthesizing these structures can also occur by inducing materials to transition into other forms by adding chemical cross-linkers, changing pH, or changing ionic composition. Understanding the generation of nanostructures in fluid environments, such as liquid organic solvents or supercritical fluids, has not been thoroughly examined, particularly those that are based on protein-based block-copolymers. Here, we examine the transformation of reconstituted silk fibroin, which has emerged as a promising biopolymer due to its biocompatibility, biodegradability, and ease of functionalization, into submicron spheres and gel networks which offer applications in tissue engineering and advanced sensors. Two types of gel networks, hydrogels and aerogels, have small pores and large surface areas that are defined by their structure. We design and analyze silk nanoparticle formation using a microfluidic device while offering an application for drug delivery. Additionally, we provide a model and characterize hydrogel formation from micelles to nanoparticles, while investigating cellular response to the hydrogel in an in vitro cell culture model. Lastly, we provide a second model of nanofiber formation during near-critical and supercritical drying and characterize the silk fibroin properties at different drying pressures which, when acting as a stabilizing matrix, shows to improve the activity of entrapped enzymes dried at different pressures. This work has created new nanostructured silk fibroin forms to benefit biomedical applications that could be applied to other fibrous proteins.

  5. A novel multifunctional biomedical material based on polyacrylonitrile: Preparation and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Huan-ling [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); Jiuzhou College of Pharmacy, Yancheng Institute of Industry Technology, Yancheng 224005 (China); Bremner, David H. [School of Science, Engineering and Technology, Kydd Building, Abertay University, Dundee DD1 1HG, Scotland (United Kingdom); Li, He-yu; Shi, Qi-quan; Wu, Jun-zi; Xiao, Rui-qiu [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); Zhu, Li-min, E-mail: lzhu@dhu.edu.cn [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China)

    2016-05-01

    Wet spun microfibers have great potential in the design of multifunctional controlled release materials. Curcumin (Cur) and vitamin E acetate (Vit. E Ac) were used as a model drug system to evaluate the potential application of the drug-loaded microfiber system for enhanced delivery. The drugs and polyacrylonitrile (PAN) were blended together and spun to produce the target drug-loaded microfiber using an improved wet-spinning method and then the microfibers were successfully woven into fabrics. Morphological, mechanical properties, thermal behavior, drug release performance characteristics, and cytocompatibility were determined. The drug-loaded microfiber had a lobed “kidney” shape with a height of 50–100 μm and width of 100–200 μm. The addition of Cur and Vit. E Ac had a great influence on the surface and cross section structure of the microfiber, leading to a rough surface having microvoids. X-ray diffraction and Fourier transform infrared spectroscopy indicated that the drugs were successfully encapsulated and dispersed evenly in the microfilament fiber. After drug loading, the mechanical performance of the microfilament changed, with the breaking strength improved slightly, but the tensile elongation increased significantly. Thermogravimetric results showed that the drug load had no apparent adverse effect on the thermal properties of the microfibers. However, drug release from the fiber, as determined through in-vitro experiments, is relatively low and this property is maintained over time. Furthermore, in-vitro cytocompatibility testing showed that no cytotoxicity on the L929 cells was found up to 5% and 10% respectively of the theoretical drug loading content (TDLC) of curcumin and vitamin E acetate. This study provides reference data to aid the development of multifunctional textiles and to explore their use in the biomedical material field. - Highlights: • Based on a wet spinning technique, a series of filaments which can be used as biomaterial

  6. Chipping fracture resistance of dental CAD/CAM restorative materials: Part 2. Phenomenological model and the effect of indenter type

    OpenAIRE

    Quinn, G. D.; Giuseppetti, A.A.; Hoffman, K. H.

    2014-01-01

    The edge chipping resistances of six CAD/CAM dental restoration materials are analyzed and correlated to other mechanical properties. A new quadratic relationship that is based on a phenomenological model is presented.

  7. Dental material artifacts on MR images.

    Science.gov (United States)

    Hinshaw, D B; Holshouser, B A; Engstrom, H I; Tjan, A H; Christiansen, E L; Catelli, W F

    1988-03-01

    Magnetic resonance (MR) imaging of the head and neck is becoming an important aid in evaluating pathologic conditions of the brain, midface, and pharynx. Certain dental materials cause artifacts during MR imaging of the lower midface. These artifacts can obscure the normal anatomy. This study describes the degree of artifact production caused by various materials commonly used in dental restorations. Of the materials tested, those causing artifacts were made of stainless steel, such as orthodontic bands used for braces, and pins or posts that are commonly drilled into teeth to provide structure or stability before filling. Materials used as temporary or permanent fillings or crowns--such as amalgam, gold alloy, aluminum, microfilled resin, and polyvinyl acrylics--did not cause artifacts in the images.

  8. Experiments in Natural and Synthetic Dental Materials: A Mouthful of Experiments

    Science.gov (United States)

    Masi, James V.

    1996-01-01

    The objectives of these experiments are to show that the area of biomaterials, especially dental materials (natural and synthetic), contain all of the elements of good and bad design, with the caveat that a person's health is directly involved. The students learn the process of designing materials for the complex interactions in the oral cavity, analyze those already used, and suggest possible solutions to the problems involved with present technology. The N.I.O.S.H. Handbook is used extensively by the students and judgement calls are made, even without extensive biology education.

  9. Electronic voting in dental materials education: the impact on students' attitudes and exam performance.

    Science.gov (United States)

    Barbour, Michele E

    2008-09-01

    Dental materials is an integral part of any undergraduate dental curriculum and is most commonly taught in a traditional didactic, lecture-based format. It suffers from the ignominy of being viewed by many as a dry, factual subject with little to excite or engage the student. In this article, the author presents the experimental use of an electronic voting (eVoting) system in an undergraduate dental materials course. The practical and aspirational aspects of its application are described. The objective was to assess the student perception of the experiment and the impact on end-of-course examination results. The eVoting system proved overwhelmingly popular with the students with 95 percent in favor of its use at the beginning of the course and 91 percent at the end. There was, however, no statistically significant impact on the results of the examination at the end of the course, when compared to the previous year's cohort of students for whom eVoting was not used. eVoting encouraged student interaction and engagement and contributed to student satisfaction but was not seen to affect the outcome measurement (end-of-course examination result).

  10. Dental Amalgam

    Science.gov (United States)

    ... and Medical Procedures Dental Devices Dental Amalgam Dental Amalgam Share Tweet Linkedin Pin it More sharing options Linkedin Pin it Email Print Dental amalgam is a dental filling material which is used ...

  11. Discrimination of tooth layers and dental restorative materials using cutting sounds.

    Science.gov (United States)

    Zakeri, Vahid; Arzanpour, Siamak; Chehroudi, Babak

    2015-03-01

    Dental restoration begins with removing carries and affected tissues with air-turbine rotary cutting handpieces, and later restoring the lost tissues with appropriate restorative materials to retain the functionality. Most restoration materials eventually fail as they age and need to be replaced. One of the difficulties in replacing failing restorations is discerning the boundary of restorative materials, which causes inadvertent removal of healthy tooth layers. Developing an objective and sensor-based method is a promising approach to monitor dental restorative operations and to prevent excessive tooth losses. This paper has analyzed cutting sounds of an air-turbine handpiece to discriminate between tooth layers and two commonly used restorative materials, amalgam and composite. Support vector machines were employed for classification, and the averaged short-time Fourier transform coefficients were selected as the features. The classifier performance was evaluated from different aspects such as the number of features, feature scaling methods, classification schemes, and utilized kernels. The total classification accuracies were 89% and 92% for cases included composite and amalgam materials, respectively. The obtained results indicated the feasibility and effectiveness of the proposed method.

  12. Bacterial spores as possible contaminants of biomedical materials and devices. [Bacillus anthracis, clostridium botulinum, C. perfringens, C. tetani

    Energy Technology Data Exchange (ETDEWEB)

    Grecz, N.; Kang, T.

    1973-01-01

    Destruction of spores on biomedical devices in drugs, and biologicals is essential for prevention of infection of patients with pathogenic sporeformers. Of particular concern are Clostridium tetani, C. perfringens, C. botulinum, Bacillus anthracis and other sporeforming pathogens. Spores are ubiquitous in nature and contamination of biomedical devices varies depending on manufacturing process, handling, raw materials and other variables. In the last 20 years the number of cases per year of specific notifiable diseases in the United States was as follows: tetanus, 120 to 500 cases, botulism, 7 to 47 cases, and anthrax, 2 to 10 cases. Gas gangrene is caused by a mixed flora consisting predominantly of sporeformers. C botulinum, which usually acts as saprophytic agent of food poisoning, may also initiate pathogenic processes; there are nine cases on record in the United States of botulism wound infections almost half of which ended in death. The spores of these organisms are distinguished by high radiation resistance and their erradication often requires severe radiation treatments. Representative bacterial spores in various suspending media show D/sub 10/ values (dose necessary to destroy 90 percent of a given population) ranging from approximately 0.1 to 0.4 Mrad. Some viruses show D/sub 10/ values up to greater than 1 Mrad. The D/sub 10/-values of spores vary depending on physical, chemical and biological factors. This variability is important in evaluation and selection of biological indicator organisms. Radiation sterilization of biomedical devices and biomedical materials must provide safety from infectious microorganisms including radiation resistant spores and viruses.

  13. [The developmental history of the dental filling materials].

    Science.gov (United States)

    Gong, Yi

    2008-10-01

    Caries may cause substantial defects in the hard tissue of teeth. The dental filling for defects is an effective method to resume teeth complete form and masticatory function as well as aesthetic effects. The filling material is artificial restorative material to fill the dental defects. Tracing back the developing process of dental filling materials, we can see the advancement of stomotology of human beings. There was a revolutionary change in the filling materials from filling dental cavity with Chinese medicinal herbs to silver paste, from establishing the composition and proportion standardization of the silver amalgam filling materials to the application of new macromolecule compound resin. This is a continuous improvement and renewal in the idea and technology of dental filling treatment so that perfects the dental filling method and enables the retention of more healthy dental tissue. In addition, it pushes the development of dental aesthetics, adhesives and technology. With the improvement of people's health standard, aesthetic demands and environmental awareness, compound resin restorative materials has become clinically preferred dental filling materials of doctors and patients in clinic.

  14. Carbon-based nanomaterials: multifunctional materials for biomedical engineering.

    Science.gov (United States)

    Cha, Chaenyung; Shin, Su Ryon; Annabi, Nasim; Dokmeci, Mehmet R; Khademhosseini, Ali

    2013-04-23

    Functional carbon-based nanomaterials (CBNs) have become important due to their unique combinations of chemical and physical properties (i.e., thermal and electrical conductivity, high mechanical strength, and optical properties), and extensive research efforts are being made to utilize these materials for various industrial applications, such as high-strength materials and electronics. These advantageous properties of CBNs are also actively investigated in several areas of biomedical engineering. This Perspective highlights different types of carbon-based nanomaterials currently used in biomedical applications.

  15. The Research of Biomedical Intelligent Polymer Materials

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi-bin; CHEN Yuan-wei; TANG Chang-wei; QIU Kai; LUO Juan; XU Cheng-yin; WAN Chang-xiu

    2004-01-01

    The properties of biomedical intelligent polymer materials can be changed obviously when there is a little physical or chemical change caused by external condition. They are in the forms of solids, solutions and the polymers on the surface of carrier, and include water solution of hydrophilic polymers, cross-linking hydrophilic polymers(i.e. hydrogels) and the polymers on the surface of carrier. The environmental stimulating factors are temperature, pH value, composition of solution, ionic intention, light intention, electric field, stress field and magnetic field etc.. The properties of intelligent polymer are those of phase, photics, mechanics, electric field, surface energy,reaction ratio, penetrating ratio and recognition etc..Stimulation-response of intelligent water-soluble polymerWater-soluble intelligent polymer can be separated out from solution under special external condition. It can be used as the switch of temperature or pH indicator. When water-soluble intelligent polymer is mixed with soluble-enzyme matter or cell suspension, the polymer can bring phase separation and react with soluble-enzyme matter or cell membrane through accepting some external stimulation. Other water-soluble intelligent polymer is that can make the main chemical group of some natural biomolecular recognition sequence section to arrange on skeleton of polymer at random. It is the same ratio as natural biomolecules.Stimulation-response of intelligent polymer of carrier surface Intelligent polymer can be fixed on the surface of solid polymer carrier through chemical grafting or physical adsorption. When the external conditions are changed, the thickness, humidity and electric field of the surface layer will be changed. Intelligent polymer can be preparated the permanence switch by precipitating into the hole of porous surface, and it can control on-off state of the hole. When protein or cell interacts with intelligent polymer surface to be placed in to open or close, they can be

  16. Biofilm Formation on Dental Restorative and Implant Materials

    NARCIS (Netherlands)

    Busscher, H. J.; Rinastiti, M.; Siswomihardjo, W.; van der Mei, H. C.

    2010-01-01

    Biomaterials for the restoration of oral function are prone to biofilm formation, affecting oral health. Oral bacteria adhere to hydrophobic and hydrophilic surfaces, but due to fluctuating shear, little biofilm accumulates on hydrophobic surfaces in vivo. More biofilm accumulates on rough than on s

  17. The Chemistry of Modern Dental Filling Materials.

    Science.gov (United States)

    Nicholson, John W.; Anstice, H. Mary

    1999-01-01

    Discusses materials used by dentists to restore teeth after decay has been removed. Shows how dental-material science is an interdisciplinary field in which chemistry plays a major part. Reviews the many developments polymer chemistry has contributed to the field of dental fillings. (CCM)

  18. Ultrashort pulse laser processing of hard tissue, dental restoration materials, and biocompatibles

    Science.gov (United States)

    Yousif, A.; Strassl, M.; Beer, F.; Verhagen, L.; Wittschier, M.; Wintner, E.

    2007-07-01

    During the last few years, ultra-short laser pulses have proven their potential for application in medical tissue treatment in many ways. In hard tissue ablation, their aptitude for material ablation with negligible collateral damage provides many advantages. Especially teeth representing an anatomically and physiologically very special region with less blood circulation and lower healing rates than other tissues require most careful treatment. Hence, overheating of the pulp and induction of microcracks are some of the most problematic issues in dental preparation. Up till now it was shown by many authors that the application of picosecond or femtosecond pulses allows to perform ablation with very low damaging potential also fitting to the physiological requirements indicated. Beside the short interaction time with the irradiated matter, scanning of the ultra-short pulse trains turned out to be crucial for ablating cavities of the required quality. One main reason for this can be seen in the fact that during scanning the time period between two subsequent pulses incident on the same spot is so much extended that no heat accumulation effects occur and each pulse can be treated as a first one with respect to its local impact. Extension of this advantageous technique to biocompatible materials, i.e. in this case dental restoration materials and titanium plasma-sprayed implants, is just a matter of consequence. Recently published results on composites fit well with earlier data on dental hard tissue. In case of plaque which has to be removed from implants, it turns out that removal of at least the calcified version is harder than tissue removal. Therefore, besides ultra-short lasers, also Diode and Neodymium lasers, in cw and pulsed modes, have been studied with respect to plaque removal and sterilization. The temperature increase during laser exposure has been experimentally evaluated in parallel.

  19. Choosing the Right Dental Material and Making Sense of the Options: Evidence and Clinical Recommendations.

    Science.gov (United States)

    Ali, Zaid; Eliyas, Shiyana; Vere, Joseph William

    2015-09-01

    Decision-making is a fundamental aspect of clinical dentistry. Advances in technology and trends towards more conservative technologies have broadened the options available to patients and dentists, increasing the range of choices and opportunities to restore teeth. With such a broad range of dental materials, there are a number of factors to consider in making an appropriate choice. We present several decision-making dilemmas. Namely; how to restore worn lower anterior teeth, what to consider when replacing crowns, materials to consider when providing cuspal protection for posterior teeth, and finally the issues to consider when selecting a luting cement. The evidence supporting different clinical choices is considered in a discussion of the various dilemmas faced.

  20. DENTAL HOT-COLD SENSITIVITY AND TRAUMATIC DENTAL INJURIES

    OpenAIRE

    Traebert, Jefferson; Martins,Luiz Gustavo Teixeira; Traebert, Eliane Silva de Azevedo; Bortoluzzi, Marcelo Carlos

    2014-01-01

    AIM: Although several studies have indicated negative impacts of traumatic dental injuries on children’s quality of life, virtually none of them have explored the possible association between them and the occurrence and dental hot-cold sensitivity. The aim of this study was to study the possible association of hot-cold dental sensitivity and history of traumatic dental injuries. MATERIAL AND METHODS: A cross-sectional study involving a representative sample of 11- to 14-year-old schoolchildre...

  1. Influence of artificial ageing on surface properties and Streptococcus mutans adhesion to dental composite materials.

    Science.gov (United States)

    Hahnel, Sebastian; Henrich, Anne; Rosentritt, Martin; Handel, Gerhard; Bürgers, Ralf

    2010-02-01

    The aim of this in vitro study was to investigate the influence of artificial ageing on the surface properties and early Streptococcus mutans adhesion to current dental composites for the direct restoration of class II defects. Three hundred and thirty specimens each were prepared from five dental composites, and were randomly allotted to various artificial ageing protocols (storage in distilled water/ethanol/artificial saliva for 7/90/365 days; thermal cycling, 6,000 cycles 5/55 degrees C). Prior and after each treatment, surface roughness (R(a)) and hydrophobicity were determined, and S. mutans adhesion (ATCC 25175; 2.5 h, 37 degrees C) was simulated with and without prior exposition to human whole saliva (2 h, 37 degrees C). Adherence of S. mutans was determined fluorometrically. Means and standard deviations were calculated, and analyzed using three-way ANOVA and post-hoc analysis (alpha = 0.05). For both R(a) and S. mutans adherence to uncoated and saliva-coated specimens, significant influences of the composite material, the ageing medium and the ageing duration have been observed; for surface hydrophobicity, significant influences of the composite material and the ageing duration were found. For uncoated specimens, significant increases in S. mutans adhesion were observed with prolonged artificial ageing, whereas significant decreases in S. mutans adhesion were found for the saliva-coated specimens. The data indicate influences of the artificial ageing method on surface parameters such as R(a) and hydrophobicity as well as microbial adhesion. The results underline the relevance of saliva coating on the outcome of studies simulating microbial adhesion, and highlight differences in the susceptibility of dental composites for the adhesion of oral bacteria.

  2. Chlorhexidine-releasing methacrylate dental composite materials.

    Science.gov (United States)

    Leung, Danny; Spratt, David A; Pratten, Jonathan; Gulabivala, Kishor; Mordan, Nicola J; Young, Anne M

    2005-12-01

    Light curable antibacterial, dental composite restoration materials, consisting of 80 wt% of a strontium fluoroaluminosilicate glass dispersed in methacrylate monomers have been produced. The monomers contained 40-100 wt% of a 10 wt% chlorhexidine diacetate (CHXA) in hydroxyethylmethacrylate (HEMA) solution and 60-0 wt% of a 50/50 mix of urethane dimethacrylate (UDMA) and triethyleneglycol dimethacrylate (TEGDMA). On raising HEMA content, light cure polymerisation rates decreased. Conversely, water sorption induced swelling and rates of diffusion controlled CHXA release from the set materials increased. Experimental composites with 50 and 90 wt% of the CHXA in HEMA solution in the monomer were shown, within a constant depth film fermentor (CDFF), to have slower rates of biofilm growth on their surfaces between 1 and 7 days than the commercial dental composite Z250 or fluoride-releasing dental cements, Fuji II LC and Fuji IX. When an excavated bovine dentine cylinder re-filled with Z250 was placed for 10 weeks in the CDFF, both bacteria and polymers from the artificial saliva penetrated between the material and dentine. With the 50 wt% experimental HEMA/CHXA formulation, this bacterial microleakage was substantially reduced. Polymer leakage, however, still occurred. Both polymer and bacterial microleakage were prevented with a 90 wt% HEMA/CHXA restoration in the bovine dentine due to swelling compensation for polymerisation shrinkage in combination with antibacterial release.

  3. Dental Assisting Course. Bilingual Vocational Instructional Materials.

    Science.gov (United States)

    Lopez-Cox, Guadalupe

    This course in dental assisting, one of a series of bilingual English-Spanish vocational education courses, is designed to prepare the student to assist the dentist at the chairside in the dental operatory, to perform reception and clerical functions, and to carry out selected dental laboratory work. The course covers an introduction to the…

  4. Recent research and development in titanium alloys for biomedical applications and healthcare goods

    Directory of Open Access Journals (Sweden)

    Mitsuo Niinomi

    2003-01-01

    Full Text Available Nb, Ta and Zr are the favorable non-toxic alloying elements for titanium alloys for biomedical applications. Low rigidity titanium alloys composed of non-toxic elements are getting much attention. The advantage of low rigidity titanium alloy for the healing of bone fracture and the remodeling of bone is successfully proved by fracture model made in tibia of rabbit. Ni-free super elastic and shape memory titanium alloys for biomedical applications are energetically developed. Titanium alloys for not only implants, but also dental products like crowns, dentures, etc. are also getting much attention in dentistry. Development of investment materials suitable for titanium alloys with high melting point is desired in dental precision castings. Bioactive surface modifications of titanium alloys for biomedical applications are very important for achieving further developed biocompatibility. Low cost titanium alloys for healthcare goods, like general wheel chairs, etc. has been recently proposed.

  5. Recent Advances in Shape Memory Soft Materials for Biomedical Applications.

    Science.gov (United States)

    Chan, Benjamin Qi Yu; Low, Zhi Wei Kenny; Heng, Sylvester Jun Wen; Chan, Siew Yin; Owh, Cally; Loh, Xian Jun

    2016-04-27

    Shape memory polymers (SMPs) are smart and adaptive materials able to recover their shape through an external stimulus. This functionality, combined with the good biocompatibility of polymers, has garnered much interest for biomedical applications. In this review, we discuss the design considerations critical to the successful integration of SMPs for use in vivo. We also highlight recent work on three classes of SMPs: shape memory polymers and blends, shape memory polymer composites, and shape memory hydrogels. These developments open the possibility of incorporating SMPs into device design, which can lead to vast technological improvements in the biomedical field.

  6. Materials Science and Technology, Volume 14, Materials Science and Technology A Comprehensive Treatment - Volume 14: Medical and Dental Materials Cahn,R.W.(ed.)/Haasen,P.(ed.)/Kramer,E.J.(ed.)

    Science.gov (United States)

    Williams, David F.

    1996-12-01

    The applications of metals, ceramics, and polymers in medical and dental engineering is becoming ever more widespread. Technologists in these fields are provided with a unique overview of materials, performances and applications. From the Contents: Williams: Biofunctionality and Biocompatibility. Kohn/Ducheyne: Materials for Bone and Joint Replacement. Baquey: Materials in the Cardiovascular System. Aebischer/Goddard/ Galletti/ Lysaght: Biomaterials and Artificial Organs. Yannas: Materials for Skin and Nerve Regeneration. Watts: Dental Restorative Materials. Williams: Materials for Oral and Maxillofacial Surgery/Materials for Ophthalmology. Causton: Medical and Dental Adhesives. Reichert/Saavedra: Materials Consideration in the Selection, Performance, and Adhesion of Polymeric Encapsulants for Implantable Sensors. Campbell/Jones: Materials for Implantable Electrodes and Electronic Devices. Brunstedt/Anderson: Materials for Drug Delivery. Jones: Materials for Fixed and Removable Prosthodontics.

  7. Nanotechnology-based restorative materials for dental caries management.

    Science.gov (United States)

    Melo, Mary A S; Guedes, Sarah F F; Xu, Hockin H K; Rodrigues, Lidiany K A

    2013-08-01

    Nanotechnology has been applied to dental materials as an innovative concept for the development of materials with better properties and anticaries potential. In this review we discuss the current progress and future applications of functional nanoparticles incorporated in dental restorative materials as useful strategies to dental caries management. We also overview proposed antimicrobial and remineralizing mechanisms. Nanomaterials have great potential to decrease biofilm accumulation, inhibit the demineralization process, to be used for remineralizing tooth structure, and to combat caries-related bacteria. These results are encouraging and open the doors to future clinical studies that will allow the therapeutic value of nanotechnology-based restorative materials to be established.

  8. Design and development of novel antibacterial Ti-Ni-Cu shape memory alloys for biomedical application

    Science.gov (United States)

    Li, H. F.; Qiu, K. J.; Zhou, F. Y.; Li, L.; Zheng, Y. F.

    2016-11-01

    In the case of medical implants, foreign materials are preferential sites for bacterial adhesion and microbial contamination, which can lead to the development of prosthetic infections. Commercially biomedical TiNi shape memory alloys are the most commonly used materials for permanent implants in contact with bone and dental, and the prevention of infections of TiNi biomedical shape memory alloys in clinical cases is therefore a crucial challenge for orthopaedic and dental surgeons. In the present study, copper has been chosen as the alloying element for design and development novel ternary biomedical Ti‒Ni‒Cu shape memory alloys with antibacterial properties. The effects of copper alloying element on the microstructure, mechanical properties, corrosion behaviors, cytocompatibility and antibacterial properties of biomedical Ti‒Ni‒Cu shape memory alloys have been systematically investigated. The results demonstrated that Ti‒Ni‒Cu alloys have good mechanical properties, and remain the excellent shape memory effects after adding copper alloying element. The corrosion behaviors of Ti‒Ni‒Cu alloys are better than the commercial biomedical Ti‒50.8Ni alloys. The Ti‒Ni‒Cu alloys exhibit excellent antibacterial properties while maintaining the good cytocompatibility, which would further guarantee the potential application of Ti‒Ni‒Cu alloys as future biomedical implants and devices without inducing bacterial infections.

  9. Design and development of novel antibacterial Ti-Ni-Cu shape memory alloys for biomedical application.

    Science.gov (United States)

    Li, H F; Qiu, K J; Zhou, F Y; Li, L; Zheng, Y F

    2016-11-29

    In the case of medical implants, foreign materials are preferential sites for bacterial adhesion and microbial contamination, which can lead to the development of prosthetic infections. Commercially biomedical TiNi shape memory alloys are the most commonly used materials for permanent implants in contact with bone and dental, and the prevention of infections of TiNi biomedical shape memory alloys in clinical cases is therefore a crucial challenge for orthopaedic and dental surgeons. In the present study, copper has been chosen as the alloying element for design and development novel ternary biomedical Ti‒Ni‒Cu shape memory alloys with antibacterial properties. The effects of copper alloying element on the microstructure, mechanical properties, corrosion behaviors, cytocompatibility and antibacterial properties of biomedical Ti‒Ni‒Cu shape memory alloys have been systematically investigated. The results demonstrated that Ti‒Ni‒Cu alloys have good mechanical properties, and remain the excellent shape memory effects after adding copper alloying element. The corrosion behaviors of Ti‒Ni‒Cu alloys are better than the commercial biomedical Ti‒50.8Ni alloys. The Ti‒Ni‒Cu alloys exhibit excellent antibacterial properties while maintaining the good cytocompatibility, which would further guarantee the potential application of Ti‒Ni‒Cu alloys as future biomedical implants and devices without inducing bacterial infections.

  10. Teaching Dental Materials Using the Personalized System of Instruction.

    Science.gov (United States)

    Schweitzer, Kathie L.; Cohen, Peter A.

    1987-01-01

    A study of the effectiveness of the personalized system of instruction (PSI) for teaching dental materials to dental hygienists compared the technique's effects to those of conventional instruction on end-of-course achievement, aptitude-achievement relationships, long-term retention, and course attitudes. (MSE)

  11. Biomedical Science, Unit II: Nutrition in Health and Medicine. Digestion of Foods; Organic Chemistry of Nutrients; Energy and Cell Respiration; The Optimal Diet; Foodborne Diseases; Food Technology; Dental Science and Nutrition. Student Text. Revised Version, 1975.

    Science.gov (United States)

    Biomedical Interdisciplinary Curriculum Project, Berkeley, CA.

    This student text presents instructional materials for a unit of science within the Biomedical Interdisciplinary Curriculum Project (BICP), a two-year interdisciplinary precollege curriculum aimed at preparing high school students for entry into college and vocational programs leading to a career in the health field. Lessons concentrate on…

  12. Evaluating mechanical properties and degradation of YTZP dental implants

    Energy Technology Data Exchange (ETDEWEB)

    Sevilla, Pablo, E-mail: pablo.sevilla@upc.edu [Biomaterials and Biomechanics Division, Department of Materials Science and Metallurgy, Technical University of Catalonia (Spain); Sandino, Clara; Arciniegas, Milena [Biomaterials and Biomechanics Division, Department of Materials Science and Metallurgy, Technical University of Catalonia (Spain); Martinez-Gomis, Jordi; Peraire, Maria [Department of Prosthodontics, Faculty of Odontology, University of Barcelona (Spain); Gil, Francisco Javier [Biomaterials and Biomechanics Division, Department of Materials Science and Metallurgy, Technical University of Catalonia (Spain)

    2010-01-01

    Lately new biomedical grade yttria stabilized zirconia (YTZP) dental implants have appeared in the implantology market. This material has better aesthetical properties than conventional titanium used for implants but long term behaviour of these new implants is not yet well known. The aim of this paper is to quantify the mechanical response of YTZP dental implants previously degraded under different time conditions and compare the toughness and fatigue strength with titanium implants. Mechanical response has been studied by means of mechanical testing following the ISO 14801 for Standards for dental implants and by finite element analysis. Accelerated hydrothermal degradation has been achieved by means of water vapour and studied by X-ray diffraction and nanoindentation tests. The results show that the degradation suffered by YTZP dental implants will not have a significant effect on the mechanical behaviour. Otherwise the fracture toughness of YTZP ceramics is still insufficient in certain implantation conditions.

  13. [Plasma technology for biomedical material applications].

    Science.gov (United States)

    Liu, Z; Li, X

    2000-03-01

    In this paper is introduced the plasma technology for the applications of several species biomaterial such as ophthalmological material, drug delivery system, tissue culture material, blood anticoagulant material as well as plasma surface clearing and plasma sterilization, and so on.

  14. The teaching of all-ceramic restorations in North American dental schools: materials and techniques employed.

    Science.gov (United States)

    Frazier, K B; Mjör, I A

    1997-01-01

    North American dental schools were surveyed to determine the types of clinical experiences and the extent of material use that predoctoral students encounter with restorative procedures that employ all-ceramic materials. The results were based on an overall response rate of 80% from the 64 surveyed schools. The majority (96%) of the 51 schools responding to the survey did offer an opportunity to become experienced with all-ceramic restorations. The selection of bases and liners for all-ceramic restorations included dentin adhesive agents, glass ionomer materials, and calcium hydroxide products, by a ratio of 5:4:1, respectively. The most commonly used impression material types were addition silicone and polyether. One or both of these materials were used by every school. Dicor glass ceramic and alumina core ceramic were the most commonly used materials by the responding schools for veneers, onlays, and crowns. Dicor glass ceramic and CAD/CAM ceramic were most commonly used for inlays. Crowns were made of more different all-ceramic material types than the other restoration classes. Fabrication of all-ceramic restorations was primarily by commercial laboratories and school technicians. Students have hands-on experience in the fabrication of all-ceramic restorations in 6% of the responding schools. Luting agents for all-ceramic restorations include dual-cured resin, in 96% of the responding schools, light-cured resin, 43%, and glass ionomer cement, 33%. Zinc phosphate, chemical-cured composite, and polycarboxylate were used by less than one fourth of the respondents. Only resin-based composite materials were used to lute ceramic veneers. Rubber dam was applied primarily during luting procedures involving all-ceramic inlays and onlays. Crowns and veneers were isolated by this method in less than 30% of the responding schools. Finishing procedures with all-ceramic restorations were accomplished with three or more instruments by 89% of the schools.

  15. Microstructure and mechanical properties of Ti-15Zr alloy used as dental implant material.

    Science.gov (United States)

    Medvedev, Alexander E; Molotnikov, Andrey; Lapovok, Rimma; Zeller, Rolf; Berner, Simon; Habersetzer, Philippe; Dalla Torre, Florian

    2016-09-01

    Ti-Zr alloys have recently started to receive a considerable amount of attention as promising materials for dental applications. This work compares mechanical properties of a new Ti-15Zr alloy to those of commercially pure titanium Grade4 in two surface conditions - machined and modified by sand-blasting and etching (SLA). As a result of significantly smaller grain size in the initial condition (1-2µm), the strength of Ti-15Zr alloy was found to be 10-15% higher than that of Grade4 titanium without reduction in the tensile elongation or compromising the fracture toughness. The fatigue endurance limit of the alloy was increased by around 30% (560MPa vs. 435MPa and 500MPa vs. 380MPa for machined and SLA-treated surfaces, respectively). Additional implant fatigue tests showed enhanced fatigue performance of Ti-15Zr over Ti-Grade4.

  16. Role of dental restoration materials in oral mucosal lichenoid lesions

    Directory of Open Access Journals (Sweden)

    Rajneesh Sharma

    2015-01-01

    Full Text Available Background: Dental restorative materials containing silver-mercury compounds have been known to induce oral lichenoid lesions. Objectives: To determine the frequency of contact allergy to dental restoration materials in patients with oral lichenoid lesions and to study the effect of removal of the materials on the lesions. Results: Forty-five patients were recruited in three groups of 15 each: Group A (lesions in close contact with dental materials, Group B (lesions extending 1 cm beyond the area of contact and Group C (no topographic relationship. Thirty controls were recruited in two groups of 15 individuals each: Group D (oral lichenoid lesions but no dental material and Group E (dental material but no oral lichenoid lesions. Patch tests were positive in 20 (44.5% patients. Mercury was the most common allergen to elicit a positive reaction in eight patients, followed by nickel (7, palladium (5, potassium dichromate (3, balsam of Peru, gold sodium thiosulphate 2 and tinuvin (2 and eugenol (1, cobalt chloride (1 and carvone (1. Seven patients elicited positive response to more than one allergen. In 13 of 20 patients who consented to removal of the dental material, complete healing was observed in 6 (30%, marked improvement in 7 (35% and no improvement in 7 (35% patients. Relief of symptoms was usually observed 3 months after removal. Limitations: Limited number of study subjects and short follow up after removal/replacement of dental restoration materials are the main limitations of this study. Conclusion: Contact allergy to amalgam is an important etiologic factor in oral lichenoid lesions and removal of restorative material should be offered to patients who have lesions in close proximity to the dental material.

  17. Novel functionalized polymeric fabric and fiber material as solid support for solid-phase synthesis and biomedical applications

    Science.gov (United States)

    Xiang, Bei

    The aim of the research is to develop novel polymer solid support by modifying or fabricating polymeric fibrous materials for peptide synthesis and biomedical applications. Originally chemical inert isotactic polypropylene (iPP) fabric was utilized and modified to serve as a functional flexible planar solid support for solid phase peptide synthesis. The modification was achieved through thermal initiated radical grafting polymerization using acrylic acid, poly (ethylene glycol) diacrylate as monomers, and benzoyl peroxide as radical initiator. The iPP fabric was successfully functionalized and possessing as high as 0.7mmol/g carboxylic acid groups. Peptide ligand LHPQF was successfully synthesized on the new functional planar support. Specific enzyme immobilization was fulfilled on the functional iPP fabric support. A commercially available ethylene-acrylic acid copolymer was made into ultrafine copolymer fiber bundles which are composed of nanofibers with diameters ranging from 200nm to 800nm. Various mixing ratios of copolymer/matrix materials were utilized to explore the effect on the final nanofiber physical properties including morphology and stability in solvents. The surface carboxylic acid groups were further converted to amino groups before the functional nanofibers can be applied in solid phase peptide synthesis. Two peptide ligands, LHPQF and HWRGWV, were also successfully synthesized on the nanofiber bundles. Streptavidin and human immunoglobulin G specific binding with the corresponding ligand which was anchored on the nanofibers was conducted successfully to illustrate the potential applications of the nanofiber materials in biomedical field. Further study on the dispersion of the ethylene-acrylic acid nanofiber bundles was pursued to take advantage of the super high active surface area of functional nanofibers. To manipulate the polymer nanofibers during synthesis and bio-assays, a technique was developed to controllably assemble and disperse the

  18. Functional Materials Based on Surface Modification of Carbon Nanotubes for Biomedical and Environmental Applications

    KAUST Repository

    Mashat, Afnan

    2015-05-01

    Since the discovery of carbon nanotubes (CNTs), they have gained much interest in many science and engineering fields. The modification of CNTs by introducing different functional groups to their surface is important for CNTs to be tailored to fit the need of specific applications. This dissertation presents several CNT-based systems that can provide biomedical and environmental advantages. In this research, polyethylenimine (PEI) and polyvinyl alcohol (PVA) were used to coat CNTs through hydrogen bonding. The release of doxorubicin (DOX, an anticancer drug) from this system was controlled by temperature. This system represents a promising method for incorporating stimuli triggered polymer-gated CNTs in controlled release applications. To create an acid responsive system CNTs were coated with 1,2-Distearoyl-snglycero- 3-Phosphoethanolamine-N-[Amino(Polyethylene glycol)2000]-(PE-PEG) and Poly(acrylic acid) modified dioleoy lphosphatidyl-ethanolamine (PE-PAA). An acidlabile linker was used to cross-link PAA, forming ALP@CNTs, thus making the system acid sensitive. The release of DOX from ALP@CNTs was found to be higher in an acidic environment. Moreover, near infrared (NIR) light was used to enhance the release of DOX from ALP@CNTs. A CNT-based membrane with controlled diffusion was prepared in the next study. CNTs were used as a component of a cellulose/gel membrane due to their optical property, which allows them to convert NIR light into heat. Poly(Nisopropylacrylamide) (PNIPAm) was used due to its thermo-sensitivity. The properties of both the CNTs and PNIPAm’s were used to control the diffusion of the cargo from the system, under the influence of NIR. CNTs were also used to fabricate an antibacterial agent, for which they were coated with polydopamine (PDA) and decorated with silver particles (Ag). Galactose (Gal) terminated with thiol groups conjugated with the above system was used to strengthen the bacterial targeting ability. The antibacterial activity of

  19. In vitro toxicity of filler particles and methacrylates used in dental composite materials. Cytokine release and cell death

    OpenAIRE

    Ansteinsson, Vibeke

    2013-01-01

    Dental polymer-based composite materials are complex materials consisting of several components, the main components being filler particles (inorganic component) and polymer matrix (organic component). The organic component consists of monomers that usually are polymerized upon activation by visible light illumination.The polymerization process is never complete, and leakage of unreacted methacrylate monomers occurs during clinical service. Degradation processes may weaken the bon...

  20. Investigation of dental alginate and agar impression materials as a brain simulant for ballistic testing.

    Science.gov (United States)

    Falland-Cheung, Lisa; Piccione, Neil; Zhao, Tianqi; Lazarjan, Milad Soltanipour; Hanlin, Suzanne; Jermy, Mark; Waddell, J Neil

    2016-06-01

    Routine forensic research into in vitro skin/skull/brain ballistic blood backspatter behavior has traditionally used gelatin at a 1:10 Water:Powder (W:P) ratio by volume as a brain simulant. A limitation of gelatin is its high elasticity compared to brain tissue. Therefore this study investigated the use of dental alginate and agar impression materials as a brain simulant for ballistic testing. Fresh deer brain, alginate (W:P ratio 91.5:8.5) and agar (W:P ratio 81:19) specimens (n=10) (11×22×33mm) were placed in transparent Perspex boxes of the same internal dimensions prior to shooting with a 0.22inch caliber high velocity air gun. Quantitative analysis to establish kinetic energy loss, vertical displacement elastic behavior and qualitative analysis to establish elasticity behavior was done via high-speed camera footage (SA5, Photron, Japan) using Photron Fastcam Viewer software (Version 3.5.1, Photron, Japan) and visual observation. Damage mechanisms and behavior were qualitatively established by observation of the materials during and after shooting. The qualitative analysis found that of the two simulant materials tested, agar behaved more like brain in terms of damage and showed similar mechanical response to brain during the passage of the projectile, in terms of energy absorption and vertical velocity displacement. In conclusion agar showed a mechanical and subsequent damage response that was similar to brain compared to alginate.

  1. Risk in the management of dental amalgam in dental medium and small entities in the department of Antioquia, Colombia

    Directory of Open Access Journals (Sweden)

    Jairo A. Ruiz

    2009-08-01

    Full Text Available This article is based on the applied research “Environmental Management of the Dental Amalgam in Antioquia, Colombia”, which was financed by the company New Stetic S. A. and the University of Antioquia. The research was carried out between 2005 and 2007 by the following groups: Biomedical Science and Technology, Precious Materials, and Pyrometallurgical and Materials Researches, and the Research and Development Division of the mentioned company. Objetive: to describe and characterize the activities about handling mercury, dental amalgam and its waste in 107 dental offices defined as medium and small, that is to say those with less than five dental chairs in the same workplace. Methodology: a poll was made in each institution filling a questionnaire about personal details of the interviewee, mercury and amalgam handling, occupational health, training, environmental conditions, and waste management. Each dental office was visited by a research engineer and an advanced engineering student who were trained in advance in order to collect the information. Results: a reflection aimed to establish integral actions and safe methodologies in the short term to promote a better quality service and a minimum risk for the people exposed to mercury and the ecosystem must be encouraged by dental and administrative staff, as well as by surveillance and control institutions and the educational institutions devoted to the formation of dental professionals.

  2. Moldable setting time evaluation between sodium alginate and bovine gelatine of glutinous rice mixture as dental putty materials

    Science.gov (United States)

    Takarini, V.; Hasratiningsih, Z.; Karlina, E.; Febrida, R.; Asri, L. A. T. W.; Purwasasmita, BS

    2017-02-01

    Putty elastomeric material is a viscous, moldable material that can be used as a dental impression to record and duplicate the tooth structure. Commercially available putty materials are hardly found in the Indonesian market. The aim of this work is to develop an alternative putty dental material from glutinous rice with two different gelling agents; sodium alginate and bovine gelatine. A commercially putty material was used as a control. The length of time required for the putty materials to set (setting time) was evaluated with compression set test. The result showed that sodium alginate and bovine gelatine gelling agents resulted in moldable putty materials that comparable to the commercial product. Glutinous rice mixed with sodium alginate gelling agent demonstrated longer setting time (more than 1 hours) compared to bovine gelatine (6 minutes). These may occur due to heat treatment applied to the bovine gelatine, while sodium alginate mixture has a chemical reaction since CaCl2 crosslink agent had been added to the mixture. Glutinous rice with bovine gelatine mixture is a promising candidate to be used as a dental putty material.

  3. Interactions of liposomes with dental restorative materials.

    Science.gov (United States)

    Nguyen, Sanko; Adamczak, Malgorzata; Hiorth, Marianne; Smistad, Gro; Kopperud, Hilde Molvig

    2015-12-01

    The in vitro adsorption and retention of liposomes onto four common types of dental restorative materials (conventional and silorane-based resin composites as well as conventional and resin-modified glass ionomer cements (GIC)) have been investigated due to their potential use in the oral cavity. Uncoated liposomes (positively and negatively charged) and pectin (low- and high-methoxylated) coated liposomes were prepared and characterized in terms of particle size and zeta potential. The adsorption of liposomes was performed by immersion, quantified by fluorescence detection, and visualized by fluorescence imaging and atomic force microscopy. Positive liposomes demonstrated the highest adsorption on all four types of materials likely due to their attractive surface charge. They also retained well (minimum 40% after 60 min) on both conventional resin composite and GIC even when exposed to simulated salivary flow. Although an intermediate initial level of adsorption was found for the pectin coated liposomes, at least 70% high methoxylated-pectin coated liposomes still remained on the conventional resin composite after 60 min flow exposure. This indicates significant contribution of hydrophobic interactions in the prolonged binding of liposomes to resin composites. Based on these results, the present paper suggests two new possible applications of liposomes in the preservation of dental restorations.

  4. Biomedical applications of the graphene-based materials.

    Science.gov (United States)

    Zhang, Baomei; Wang, Yang; Zhai, Guangxi

    2016-04-01

    Graphene, a rapidly rising star, has gained extensive research interests lately due to its excellent properties--such as the exceptional optical, electrical, thermal and mechanical features--which are superior to other materials, so it is called "two-dimensional magical materials". This article presents diverse types and various properties of graphene-based materials, and the current methods for the surface modifications of the graphene-based materials are briefly described. In addition, the in vivo and in vitro cytotoxicity of graphene-based materials are comprehensively discussed. What's more, a summary of its biomedical applications such as drug/gene delivery, photothermal therapy, photodynamic therapy and multimodality therapy is also offered. Finally, an outlook of the graphene-based materials and the challenges in this field are briefly discussed.

  5. Cell death effects of resin-based dental material compounds and mercurials in human gingival fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Reichl, Franz-Xaver [Walther-Straub-Institute of Pharmacology and Toxicology, Munich (Germany); Ludwig-Maximilians-University, Department of Operative Dentistry and Periodontology, Munich (Germany); Esters, Magali; Simon, Sabine; Seiss, Mario [Walther-Straub-Institute of Pharmacology and Toxicology, Munich (Germany); Kehe, Kai [Bundeswehr Institute of Pharmacology and Toxicology, Munich (Germany); Kleinsasser, Norbert [University of Regensburg, Head and Neck Surgery, Department of Otolaryngology, Regensburg (Germany); Folwaczny, Matthias; Glas, Juergen; Hickel, Reinhard [Ludwig-Maximilians-University, Department of Operative Dentistry and Periodontology, Munich (Germany)

    2006-06-15

    In order to test the hypothesis that released dental restorative materials can reach toxic levels in human oral tissues, the cytotoxicities of the resin-based dental (co)monomers hydroxyethylmethacrylate (HEMA), triethyleneglycoldimethacrylate (TEGDMA), urethanedimethacrylate (UDMA), and bisglycidylmethacrylate (BisGMA) compared with methyl mercury chloride (MeHgCl) and the amalgam component mercuric chloride (HgCl{sub 2}) were investigated on human gingival fibroblasts (HGF) using two different test systems: (1) the modified XTT-test and (2) the modified H 33342 staining assay. The HGF were exposed to various concentrations of the test-substances in all test systems for 24 h. All tested (co)monomers and mercury compounds significantly (P<0.05) decreased the formazan formation in the XTT-test. EC{sub 50} values in the XTT assay were obtained as half-maximum-effect concentrations from fitted curves. Following EC{sub 50} values were found (mean [mmol/l]; s.e.m. in parentheses; n=12; * significantly different to HEMA): HEMA 11.530 (0.600); TEGDMA* 3.460 (0.200); UDMA* 0.106 (0.005); BisGMA* 0.087 (0.001); HgCl{sub 2}* 0.013 (0.001); MeHgCl* 0.005 (0.001). Following relative toxicities were found: HEMA 1; TEGDMA 3; UDMA 109; BisGMA 133; HgCl{sub 2} 887; MeHgCl 2306. A significant (P<0.05) increase of the toxicity of (co)monomers and mercurials was found in the XTT-test in the following order: HEMA < TEGDMA < UDMA < BisGMA < HgCl{sub 2} < MeHgCl. TEGDMA and MeHgCl induced mainly apoptotic cell death. HEMA, UDMA, BisGMA, and HgCl{sub 2} induced mainly necrotic cell death. The results of this study indicate that resin composite components have a lower toxicity than mercury from amalgam in HGF. HEMA, BisGMA, UDMA, and HgCl{sub 2} induced mainly necrosis, but it is rather unlikely that eluted substances (solely) can reach concentrations, which might induce necrotic cell death in the human physiological situation, indicating that other (additional) factors may be involved in

  6. Matching the optical properties of direct esthetic dental restorative materials to those of human enamel and dentin

    Science.gov (United States)

    Ragain, James Carlton, Jr.

    One of the goals of the restorative dentist is to restore the appearance of the natural dentition. Clinical matching of teeth and restorative materials are seldom accurate and shade selection techniques are subjective. The first specific aim of this research was to characterize the optical absorption and scattering that occurs within enamel, dentin, and composite resin and compomer restorative materials and to relate those phenomena to translucency and color. The second aim was to evaluate small color differences among composite restorative materials which would be detectable by humans. The last aim was to lay the foundation for developing an improved model of specifying layers of dental restorative materials in order to match the translucency and color to those of human enamel. The Kubelka-Munk theory was validated for enamel, dentin, and the restorative materials. These tissues and materials were then characterized in terms of their color parameters. Tooth cores were also characterized in terms of color space parameters. Human subjects were evaluated for their abilities to discriminate small color differences in the dental composite resin materials. The following conclusions were derived from this study: (1) Kubelka-Munk theory accurately predicts the diffuse reflectance spectra of enamel, dentin, and the direct esthetic dental restorative materials studied. (2) Scattering and absorption coefficients of the dental tissues and esthetic restorative materials can be directly calculated from diffuse reflectance measurements of a uniformly thick slab of tissue/material using black and white backings and the appropriate refractive index. (3) For tooth cores, there is a positive correlation between L* and b* and a negative correlation between L* and a*. (4) The range of translucency parameters for the restorative materials studied does not match those of enamel and dentin. (5) None of the shades of the dental composite resin restorative materials studied fit into the

  7. Laser micro-structuring of surfaces for applications in materials and biomedical science

    Science.gov (United States)

    Sarzyński, Antoni; Marczak, Jan; Strzelec, Marek; Rycyk, Antoni; CzyŻ, Krzysztof; Chmielewska, Danuta

    2016-12-01

    Laser radiation is used, among others, for surface treatment of various materials. At the Institute of Optoelectronics, under the direction of the late Professor Jan Marczak, a number of works in the field of laser materials processing were performed. Among them special recognition deserves flagship work of Professor Jan Marczak: implementation in Poland laser cleaning method of artworks. Another big project involved the direct method of laser interference lithography. These two projects have already been widely discussed in many national and international scientific conferences. They will also be discussed at SLT2016. In addition to these two projects in the Laboratory of Lasers Applications many other works have been carried out, some of which will be separately presented at the SLT2016 Conference. These included laser decorating of ceramics and glass (three projects completed in cooperation with the Institute of Ceramics and Building Materials), interference structuring medical implants (together with the Warsaw University of Technology), testing the adhesion of thin layers (project implemented together with IFTR PAS), structuring layers of DLC for growing endothelial cells (together with IMMS PAS), engraving glass for microfluidic applications, metal marking, sapphire cutting and finally the production of microsieves for separating of blood cells.

  8. Textural Properties of Hybrid Biomedical Materials Made from Extracts of Tournefortia hirsutissima L. Imbibed and Deposited on Mesoporous and Microporous Materials

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Hernández

    2016-01-01

    Full Text Available Our research group has developed a group of hybrid biomedical materials potentially useful in the healing of diabetic foot ulcerations. The organic part of this type of hybrid materials consists of nanometric deposits, proceeding from the Mexican medicinal plant Tournefortia hirsutissima L., while the inorganic part is composed of a zeolite mixture that includes LTA, ZSM-5, clinoptilolite, and montmorillonite (PZX as well as a composite material, made of CaCO3 and montmorillonite (NABE. The organic part has been analyzed by GC-MS to detect the most abundant components present therein. In turn, the inorganic supports were characterized by XRD, SEM, and High Resolution Adsorption (HRADS of N2 at 76 K. Through this latter methodology, the external surface area of the hybrid materials was evaluated; besides, the most representative textural properties of each substrate such as total pore volume, pore size distribution, and, in some cases, the volume of micropores were calculated. The formation and stabilization of nanodeposits on the inorganic segments of the hybrid supports led to a partial blockage of the microporosity of the LTA and ZSM5 zeolites; this same effect occurred with the NABE and PZX substrates.

  9. Cellulose nanocrystals in nanocomposite approach: Green and high-performance materials for industrial, biomedical and agricultural applications

    Science.gov (United States)

    Fortunati, E.; Torre, L.

    2016-05-01

    The need to both avoid wastes and find new renewable resources has led to a new and promising research based on the possibility to revalorize the biomass producing sustainable chemicals and/or materials which may play a major role in replacing systems traditionally obtained from non-renewable sources. Most of the low-value biomass is termed lignocellulosic, referring to its main constituent biopolymers: cellulose, hemicelluloses and lignin. In this context, nanocellulose, and in particular cellulose nanocrystals (CNC), have gain considerable attention as nanoreinforcement for polymer matrices, mainly biodegradable. Derived from the most abundant polymeric resource in nature and with inherent biodegradability, nanocellulose is an interesting nanofiller for the development of nanocomposites for industrial, biomedical and agricultural applications. Due to the high amount of hydroxyl groups on their surface, cellulose nanocrystals are easy to functionalize. Well dispersed CNC are able, in fact, to enhance several properties of polymers, i.e.: thermal, mechanical, barrier, surface wettability, controlled of active compound and/or drug release. The main objective here is to give a general overview of CNC applications, summarizing our recent developments of bio-based nanocomposite formulations reinforced with cellulose nanocrystals extracted from different natural sources and/or wastes for food packaging, medical and agricultural sectors.

  10. Finite element calculation of residual stress in dental restorative material

    Science.gov (United States)

    Grassia, Luigi; D'Amore, Alberto

    2012-07-01

    A finite element methodology for residual stresses calculation in dental restorative materials is proposed. The material under concern is a multifunctional methacrylate-based composite for dental restorations, activated by visible light. Reaction kinetics, curing shrinkage, and viscoelastic relaxation functions were required as input data on a structural finite element solver. Post cure effects were considered in order to quantify the residual stresses coming out from natural contraction with respect to those debited to the chemical shrinkage. The analysis showed for a given test case that residual stresses frozen in the dental restoration at uniform temperature of 37°C are of the same order of magnitude of the strength of the dental composite material per se.

  11. Handbook of Coherent-Domain Optical Methods Biomedical Diagnostics, Environmental Monitoring, and Materials Science

    CERN Document Server

    2013-01-01

    This Handbook provides comprehensive coverage of laser and coherent-domain methods as applied to biomedicine, environmental monitoring, and materials science. Worldwide leaders in these fields describe the fundamentals of light interaction with random media and present an overview of basic research. The latest results on coherent and polarization properties of light scattered by random media, including tissues and blood, speckles formation in multiple scattering media, and other non-destructive interactions of coherent light with rough surfaces and tissues, allow the reader to understand the principles and applications of coherent diagnostic techniques. The expanded second edition has been thoroughly updated with particular emphasis on novel coherent-domain techniques and their applications in medicine and environmental science. Volume 1 describes state-of-the-art methods of coherent and polarization optical imaging, tomography and spectroscopy; diffusion wave spectroscopy; elastic, quasi-elastic and inelasti...

  12. Biomedical signals and systems

    CERN Document Server

    Tranquillo, Joseph V

    2013-01-01

    Biomedical Signals and Systems is meant to accompany a one-semester undergraduate signals and systems course. It may also serve as a quick-start for graduate students or faculty interested in how signals and systems techniques can be applied to living systems. The biological nature of the examples allows for systems thinking to be applied to electrical, mechanical, fluid, chemical, thermal and even optical systems. Each chapter focuses on a topic from classic signals and systems theory: System block diagrams, mathematical models, transforms, stability, feedback, system response, control, time

  13. Biomedical Sensors and Instruments

    CERN Document Server

    Tagawa, Tatsuo

    2011-01-01

    The living body is a difficult object to measure: accurate measurements of physiological signals require sensors and instruments capable of high specificity and selectivity that do not interfere with the systems under study. As a result, detailed knowledge of sensor and instrument properties is required to be able to select the "best" sensor from one of the many designed to meet these challenges. From the underlying principles to practical applications, this updated edition of Biomedical Sensors and Instruments provides an easy-to-understand introduction to the various kinds of biome

  14. Nanoparticulate zinc oxide as a coating material for orthopedic and dental implants.

    Science.gov (United States)

    Memarzadeh, Kaveh; Sharili, Amir S; Huang, Jie; Rawlinson, Simon C F; Allaker, Robert P

    2015-03-01

    Orthopedic and dental implants are prone to infection. In this study, we describe a novel system using zinc oxide nanoparticles (nZnO) as a coating material to inhibit bacterial adhesion and promote osteoblast growth. Electrohydrodynamic atomisation (EHDA) was employed to deposit mixtures of nZnO and nanohydroxyapatite (nHA) onto the surface of glass substrates. Nano-coated substrates were exposed to Staphylococcus aureus suspended in buffered saline or bovine serum to determine antimicrobial activity. Our results indicate that 100% nZnO and 75% nZnO/25% nHA composite-coated substrates have significant antimicrobial activity. Furthermore, osteoblast function was explored by exposing cells to nZnO. UMR-106 cells exposed to nZnO supernatants showed minimal toxicity. Similarly, MG-63 cells cultured on nZnO substrates did not show release of TNF-α and IL-6 cytokines. These results were reinforced by both proliferation and differentiation studies which revealed that a substrate coated with exclusively nZnO is more efficient than composite surface coatings. Finally, electron and light microscopy, together with immunofluorescence staining, revealed that all cell types tested, including human mesenchymal cell (hMSC), were able to maintain normal cell morphology when adhered onto the surface of the nano-coated substrates. Collectively, these findings indicate that nZnO can, on its own, provide an optimal coating for future bone implants that are both antimicrobial and biocompatible.

  15. Zirconium: biomedical and nephrological applications.

    Science.gov (United States)

    Lee, David B N; Roberts, Martin; Bluchel, Christian G; Odell, Ross A

    2010-01-01

    Recent years have witnessed a rapid increase in the use of zirconium (Zr)-containing compounds in artificial internal organs. Examples include dental implants and other restorative practices, total knee and hip replacement, and middle-ear ossicular chain reconstruction. In nephrological practice, Zr-containing sorbents have been used in hemofiltration, hemodialysis, peritoneal dialysis, and in the design and construction of wearable artificial kidneys. Zr compounds continue to be widely and extensively used in deodorant and antiperspirant preparations. In the public health arena, Zr compounds have been studied or used in controlling phosphorus pollution and in the reclamation of poison and bacteria-contaminated water. Experimental and clinical studies support the general consensus that Zr compounds are biocompatible and exhibit low toxicity. Reports on possible Zr-associated adverse reactions are rare and, in general, have not rigorously established a cause-and-effect relationship. Although publications on the use of Zr compounds have continued to increase in recent years, reports on Zr toxicity have virtually disappeared from the medical literature. Nevertheless, familiarity with, and continued vigilant monitoring of, the use of these compounds are warranted. This article provides an updated review on the biomedical use of Zr compounds.

  16. ELECTROCHEMICAL AND MECHANICAL EVALUATION OF SOME DENTAL MATERIALS EMPLOYED FOR IMMOBILIZATION DEVICES

    Directory of Open Access Journals (Sweden)

    ANA MARIA FATU

    2016-03-01

    Full Text Available Measurement of corrosion potential is a relatively simple concept, an unanimously accepted notion in industry for the monitorization of steel corrosion, in building industry and in other structures. Equally, in the last decades, this parameter has been intensively utilized for characterizing dental alloys in either natural oral environment or in simulated solutions. The corrosion potential may be measured directly versus a reference electrode, characterized by a highly stable semi-cell potential. In this respect, a reference electrode (or a separated sensor of the material to be monitorized is introduced in the corrosive medium together with the metal or alloy under study, and the potential is measured directly with a millivoltmeter with very high input impedance. Additional details on the processes occurring in the system may be acquired if analyzing the curves of cyclic polarization, for whose obtaining the potential of the electrode formed with the investigated alloy is increased, at constant rate, in positive direction, up to a pre-established value, followed by its scavenging in reverse direction (towards negative values until reaching the initial value or some other value. During scavenging of the potential, the electric power passing through the solution between the working electrode and an auxilliary (platinum-made electrode is measured.

  17. Evaluating the Effect of Dental Filling Material and Filling Depth on the Strength and Deformation of Filled Teeth

    Directory of Open Access Journals (Sweden)

    Seifollah Gholampour

    2016-10-01

    Full Text Available ackground and aim: It is important to evaluate the effect of the type of filling material on deformation and strength of tooth after filling and also the effect of filling depth on quality of restoration of a decayed tooth. Material and Methods: The Orthopantomogram (OPG of the first and second molars of a 28-year-old man was made and the teeth were 3D modeled. The stress-deformation analysis was then performed on the models in the three states of normal tooth, tooth filled with amalgam and tooth filled with composite using finite element method under a distributed load of 400N equivalent to chewing force. Two values (1/2 and 1/3 of the tooth height were considered for filling depth in the analyses. Results: The results showed that the normal first molar was exposed to a 7.2% greater risk of dental injuries compared to the normal second molar and also a greater stress is created in it when it is filled with composite. The first molar filled with a composite material is 13.7% weaker than the normal tooth while it is almost as strong as a normal tooth when it is filled with amalgam. The effect of the type of filling material on the strength and deformation of the second molar was trivial. Conclusion: Amalgam is a more proper dental filling material for the first molar although a 16.7% change in drilling depth is needed for tooth preparation. Dental filling material and filling depth have a small effect on the strength and deformation of filled second molars.

  18. Influence of the Light Source and Curing Parameters on Microhardness of a Silorane-Based Dental Composite Material

    OpenAIRE

    Malara P.; Czech Z.; Świderski W.

    2016-01-01

    The aim of the study was to determine the influence of the light source and the light-curing parameters (the distance of the material from the light source and time of light-curing) on microhardness of Flitek Silorane dental composite material. Standardized samples of Filtek Silorane material were cured using two types of Light Curing Units (LCUs) – halogen and LED. The distance of the light source and time of curing differed between samples. The Knoop’s microhardness was tested using microha...

  19. [Exploration of basic restorative dental materials teaching in the field of dental technology].

    Science.gov (United States)

    Jin, Yan-ting

    2012-12-01

    This study was to compare the difference of the existing course materials of basic restorative dental with the past materials, found out the weakness of teaching mode before the reform, and explored the reform in education through teaching content, method and evaluation, in order to improve the teaching quality.

  20. Evaluation of implant-materials as cell carriers for dental stem cells under in vitro conditions

    OpenAIRE

    Gosau, Martin; Viale-Bouroncle, Sandra; Eickhoff, Hannah; Prateeptongkum, Esthera; Reck, Anja; Götz, W.; Klingelhöffer, Christoph; Müller, Steffen; Morsczeck, Christian

    2015-01-01

    Background Dental stem cells in combination with implant materials may become an alternative to autologous bone transplants. For tissue engineering different types of soft and rigid implant materials are available, but little is known about the viability and the osteogenic differentiation of dental stem cells on these different types of materials. According to previous studies we proposed that rigid bone substitute materials are superior to soft materials for dental tissue engineering. Method...

  1. Micro energy-dispersive X-ray fluoresence mapping of enamel and dental materials after chemical erosion.

    Science.gov (United States)

    Soares, Luís Eduardo Silva; de Oliveira, Rodrigo; Nahórny, Sídnei; Santo, Ana Maria do Espírito; Martin, Airton Abrahão

    2012-10-01

    Energy-dispersive X-ray fluorescence was employed to test the hypothesis that beverage consumption or mouthwash utilization will change the chemical properties of dental materials and enamel mineral content. Bovine enamel samples (n = 45) each received two cavity preparations (n = 90), each pair filled with one of three dental materials (R: nanofilled composite resin; GIC: glass-ionomer cement; RMGIC: resin-modified GIC). Furthermore, they were treated with three different solutions (S: saliva; E: erosion/Pepsi Twist®; or EM: erosion+mouthwash/Colgate Plax®). It was found that mineral loss in enamel was greater in GICE samples than in RE > RMGICE > RMGICEM > REM > GICEM. An increased percentage of Zr was found in REM indicating organic matrix degradation. Dental materials tested (R, GIC, and RMGIC) were not able to protect adjacent enamel from acid erosion by the soft drink tested. The use of mouthwash promoted protection of enamel after erosion by the soft drink. To avoid chemical dissolution by mouthwashes, protection by resin composites with surface sealants is recommended.

  2. On the surface elemental composition of non-corroded and corroded dental ceramic materials in vitro.

    Science.gov (United States)

    Milleding, P; Karlsson, S; Nyborg, L

    2003-06-01

    Dental ceramics are traditionally looked upon as inert materials. As many are glass phased, it may be hypothesized that they will be subjected to glass corrosion in aqueous environments. The aim of the study was therefore to analyze the surface elemental composition of glass-phased and all-crystalline ceramics, before and after low- and high-intensity, in vitro corrosion (milli-Q-water at 37+/-2 degrees C for 18 h and 4% acetic acid at 80+/-2 degrees C for 18 h, respectively). The analysis of the surface elemental composition was performed using ESCA. The hypothesis was confirmed. After high-intensity corrosion, the complete wash out of alkali ions, alkaline-earth ions and elemental alumina was found, leaving behind a surface totally dominated by silica. The all-crystalline ceramics, densely sintered alumina and yttria-partially stabilized tetragonal zirconia, displayed only minor surface changes, even after high-intensity corrosion. In comparison to the corrosion testing in acid, the corrosion process in milli-Q-water did not produce different results in principle, except for the lower magnitude of the depletion of alkali ions and the virtually unchanged level of elemental alumina. Unexpectedly, no substantial difference in surface degradation was found between the glass ceramic and the ordinary porcelain-fused-to-metal ceramic or between ceramics of higher sintering temperature and those of low or ultra-low sintering temperature. The composition and microstructure alone did not appear to provide a full explanation for the inter-individual differences in surface corrosion when exposed to comparable environmental conditions.

  3. Progress in material design for biomedical applications.

    Science.gov (United States)

    Tibbitt, Mark W; Rodell, Christopher B; Burdick, Jason A; Anseth, Kristi S

    2015-11-24

    Biomaterials that interface with biological systems are used to deliver drugs safely and efficiently; to prevent, detect, and treat disease; to assist the body as it heals; and to engineer functional tissues outside of the body for organ replacement. The field has evolved beyond selecting materials that were originally designed for other applications with a primary focus on properties that enabled restoration of function and mitigation of acute pathology. Biomaterials are now designed rationally with controlled structure and dynamic functionality to integrate with biological complexity and perform tailored, high-level functions in the body. The transition has been from permissive to promoting biomaterials that are no longer bioinert but bioactive. This perspective surveys recent developments in the field of polymeric and soft biomaterials with a specific emphasis on advances in nano- to macroscale control, static to dynamic functionality, and biocomplex materials.

  4. HLA-Association in Patients with Intolerance to Mercury and Other Metals in Dental Materials

    Directory of Open Access Journals (Sweden)

    J. Procházková

    2000-01-01

    Full Text Available A group of selected 25 patients with serious intolerance to heavy metals used for dental restoration were examined for HLA antigens. A significant increase for HLA – B37, B47 and DR4 was found. The value of the relative risk is not significant after correction for the number of antigens tested and therefore further studies of more patients are needed.

  5. Various Effects of Sandblasting of Dental Restorative Materials.

    Directory of Open Access Journals (Sweden)

    Goro Nishigawa

    Full Text Available Sandblasting particles which remain on the surfaces of dental restorations are removed prior to cementation. It is probable that adhesive strength between luting material and sandblasting particle remnants might exceed that with restorative material. If that being the case, blasting particles adhere to sandblasted material surface could be instrumental to increasing adhesive strength like underlying bonding mechanism between luting material and silanized particles of tribochemical silica coating-treated surface. We hypothesize that ultrasonic cleaning of bonding surfaces, which were pretreated with sandblasting, may affect adhesive strength of a resin luting material to dental restorative materials.We therefore observed adhesive strength of resin luting material to aluminum oxide was greater than those to zirconia ceramic and cobalt-chromium alloy beforehand. To measure the shear bond strengths of resin luting material to zirconia ceramic and cobalt-chromium alloy, forty specimens of each restorative material were prepared. Bonding surfaces were polished with silicon abrasive paper and then treated with sandblasting. For each restorative material, 40 sandblasted specimens were equally divided into two groups: ultrasonic cleaning (USC group and non-ultrasonic cleaning (NUSC group. After resin luting material was polymerized on bonding surface, shear test was performed to evaluate effect of ultrasonic cleaning of bonding surfaces pretreated with sandblasting on bond strength.For both zirconia ceramic and cobalt-chromium alloy, NUSC group showed significantly higher shear bond strength than USC group.Ultrasonic cleaning of dental restorations after sandblasting should be avoided to retain improved bonding between these materials.

  6. Handbook of coherent domain optical methods biomedical diagnostics, environmental and material science

    CERN Document Server

    2004-01-01

    For the first time in one set of books, coherent-domain optical methods are discussed in the framework of various applications, which are characterized by a strong light scattering. A few chapters describe basic research containing the updated results on coherent and polarized light non-destructive interactions with a scattering medium, in particular, diffraction, interference, and speckle formation at multiple scattering. These chapters allow for understanding coherent-domain diagnostic techniques presented in later chapters. A large portion of Volume I is dedicated to analysis of various aspects of optical coherence tomography (OCT) - a very new and growing field of coherent optics. Two chapters on laser scanning confocal microscopy give insight to recent extraordinary results on in vivo imaging and compare the possibilities and achievements of confocol, excitation multiphoton, and OCT microscopy. This two volume reference contains descriptions of holography, interferometry and optical heterodyning techniqu...

  7. Polylactic Acid Based Nanocomposites: Promising Safe and Biodegradable Materials in Biomedical Field

    OpenAIRE

    Lili Sha; Zhaofeng Chen; Zhou Chen; Aili Zhang; Zhaogang Yang

    2016-01-01

    Polylactic acid (PLA) is widely used in biological areas due to its excellent compatibility, bioabsorbability, and degradation behavior in human bodies. Pure polylactic acid has difficulty in meeting all the requirements that specific field may demand. Therefore, PLA based nanocomposites are extensively investigated over the past few decades. PLA based nanocomposites include PLA based copolymers in nanometer size and nanocomposites with PLA or PLA copolymers as matrix and nanofillers as annex...

  8. Carbon nanotube-coated silicone as a flexible and electrically conductive biomedical material

    Energy Technology Data Exchange (ETDEWEB)

    Matsuoka, Makoto, E-mail: matsuoka@den.hokudai.ac.jp [Department of Oral and Maxillofacial Surgery, Graduate School of Dental Medicine, Hokkaido University, Kita 13 Nishi 7, Kita-ku, Sapporo 060-8586 (Japan); Japan Society for the Promotion of Science (Japan); Akasaka, Tsukasa [Department of Dental Materials and Engineering, Graduate School of Dental Medicine, Hokkaido University, Kita 13 Nishi 7, Kita-ku, Sapporo 060-8586 (Japan); Totsuka, Yasunori [Department of Oral and Maxillofacial Surgery, Graduate School of Dental Medicine, Hokkaido University, Kita 13 Nishi 7, Kita-ku, Sapporo 060-8586 (Japan); Watari, Fumio [Department of Dental Materials and Engineering, Graduate School of Dental Medicine, Hokkaido University, Kita 13 Nishi 7, Kita-ku, Sapporo 060-8586 (Japan)

    2012-04-01

    Artificial cell scaffolds that support cell adhesion, growth, and organization need to be fabricated for various purposes. Recently, there have been increasing reports of cell patterning using electrical fields. We fabricated scaffolds consisting of silicone sheets coated with single-walled (SW) or multi-walled (MW) carbon nanotubes (CNTs) and evaluated their electrical properties and biocompatibility. We also performed cell alignment with dielectrophoresis using CNT-coated sheets as electrodes. Silicone coated with 10 {mu}g/cm{sup 2} SWCNTs exhibited the least sheet resistance (0.8 k{Omega}/sq); its conductivity was maintained even after 100 stretching cycles. CNT coating also improved cell adhesion and proliferation. When an electric field was applied to the cell suspension introduced on the CNT-coated scaffold, the cells became aligned in a pearl-chain pattern. These results indicate that CNT coating not only provides electro-conductivity but also promotes cell adhesion to the silicone scaffold; cells seeded on the scaffold can be organized using electricity. These findings demonstrate that CNT-coated silicone can be useful as a biocompatible scaffold. - Highlights: Black-Right-Pointing-Pointer We fabricated a CNT-coated silicone which has conductivity and biocompatibility. Black-Right-Pointing-Pointer The conductivity was maintained after 100 cycles of stretching. Black-Right-Pointing-Pointer CNT coatings enabled C2C12 cells adhere to the silicone surface. Black-Right-Pointing-Pointer Cells were aligned with dielectrophoresis between CNT-coated silicone surfaces.

  9. Evidence-based dentistry as it relates to dental materials.

    Science.gov (United States)

    Bayne, Stephen C; Fitzgerald, Mark

    2014-01-01

    Evidence-based dentistry (EBD) is reviewed in depth to underscore the limitations for evidence-based dental materials information that exist at this time. Anecdotal estimates of evidence for dental practice are in the range of 8 percent to 10 percent. While the process of evaluating the literature base for dental evidence began 20 years ago, it was not practical to implement it until high-speed wireless connections, open access to journals, and omnipresent connections via smart phones became a reality. EBD includes five stages of information collection and analysis, starting with a careful definition of a clinical question using the PICO(T) approach. Clinical evidence in randomized control trials is considered the best. Clinical trial perspectives (prospective, cross-sectional, retrospective) and outcome designs (RCTs, SCTs, CCTs, cohort studies, case-control studies) are quite varied. Aggregation techniques (including meta-analyses) allow meaningful combinations of clinical data from trials with similar designs but with fewer rigors. Appraisals attempt to assess the entire evidence base without bias and answer clinical questions. Varying intensities to these approaches, Cochrane Collaboration, ADA-EBD Library, UTHSCSA CATs Library, are used to answer questions. Dental materials evidence from clinical trials is infrequent, short-term, and often not compliant with current guidelines (registration, CONSORT, PRISMA). Reports in current evidence libraries indicate less than 5 percent of evidence is related to restorative dental materials.

  10. Embryotoxicity assays for leached components from dental restorative materials

    OpenAIRE

    Mummolo Stefano; Tecco Simona; Gallusi Gianni; Farini Donatella; Klinger Francesca G; Marzo Giuseppe; Libonati Antonio; De Felici Massimo; Campanella Vincenzo

    2011-01-01

    Abstract Background Currently, there are no suitable assays available to evaluate the embryotoxicity of leached components from restorative dental materials. Methods The effect of the medium conditioned by composites and amalgam on mouse blastocysts in vitro was tested. The materials were also subcutaneously implanted, and the effect of the medium supplemented with serum from the host blood was evaluated in the embryotoxicity assay. The embryo implantation rate in the material-transplanted mo...

  11. Development of Biomedical Polymer-Silicate Nanocomposites: A Materials Science Perspective

    Directory of Open Access Journals (Sweden)

    Chia-Jung Wu

    2010-04-01

    Full Text Available Biomedical polymer-silicate nanocomposites have potential to become critically important to the development of biomedical applications, ranging from diagnostic and therapeutic devices, tissue regeneration and drug delivery matrixes to various bio-technologies that are inspired by biology but have only indirect biomedical relation. The fundamental understanding of polymer-nanoparticle interactions is absolutely necessary to control structure-property relationships of materials that need to work within the chemical, physical and biological constraints required by an application. This review summarizes the most recent published strategies to design and develop polymer-silicate nanocomposites (including clay based silicate nanoparticles and bioactive glass nanoparticles for a variety of biomedical applications. Emerging trends in bio-technological and biomedical nanocomposites are highlighted and potential new fields of applications are examined.

  12. Influence of metal dental materials on MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchihashi, Toshio; Chiba, Michiko; Yoshizawa, Satoshi; Sasaki, Sadayuki; Maki, Toshio; Kitagawa, Matsuo; Suzuki, Takeshi [Nippon Medical School, Tokyo (Japan). Main Hospital; Nakata, Minoru; Fujita, Isao

    1998-11-01

    Differences in magnetic susceptibility produce artifacts and signal loss in magnetic resonance imaging (MRI). This study was undertaken to compare the degree of artifacts on MRI caused by metallic dental materials. The influence on MRI of six types of dental alloys, a dental implant, orthodontic appliance, and magnetic attachment was investigated. Among the dental metals, nickel-chromium alloy and cobalt-chromium alloy, which have ferromagnetism, caused significant metal artifacts. Gold-platinum alloy, gold-silver-palladium alloy, silver alloy, and amalgam alloy produced slight metal artifacts. The orthodontic appliance mainly consisted of iron, and the keeper for its magnetic attachment was made of stainless steel. For these reasons, marked metal artifacts and signal loss could be seen in both of them owing to their ferromagnetism. These results suggest that orthodontic appliances and magnetic attachments impair evaluation of the GRE and EPI techniques. It is therefore preferable to use predominantly diamagnetic or paramagnetic dental materials for MRI of the head and neck. Removable keepers should be used more widely to prevent metal artifacts and enhance safety on MRI. (author)

  13. A new approach to influence contact angle and surface free energy of resin-based dental restorative materials.

    Science.gov (United States)

    Rüttermann, Stefan; Trellenkamp, Taina; Bergmann, Nora; Raab, Wolfgang H-M; Ritter, Helmut; Janda, Ralf

    2011-03-01

    The purpose of the present study was to identify novel delivery systems and active agents which increase the water contact angle and reduce the surface free energy when added to resin-based dental restorative materials. Two delivery systems based on zeolite or novel polymeric hollow beads (Poly-Pore), loaded with two low surface tension active agents (hydroxy functional polydimethylsiloxane and polydimethylsiloxane) or a polymerizable active agent (silicone polyether acrylate) were used to modify commonly formulated experimental dental resin composites. The non-modified resin was used as a standard (ST). Flexural strength, flexural modulus, water sorption, solubility, polymerization shrinkage, surface roughness Ra, contact angle θ, total surface free energy γS, and the apolar γSLW, polar γSAB, Lewis acid γS+ and base γS- components, and the active agents surface tensions γL were determined (Pmaterials had significantly higher θ but significantly lower γS, γSAB and γS- than the ST. A Poly-Pore/polydimethyl siloxane delivery system yielded the highest θ (110.9±3.5°) acceptable physical properties and the lowest values for γSLW and γS-. Among the modified materials the polymerizable materials containing active agents had the lowest γAB and the highest γS+ and γS-. Although not significant, both of the zeolite delivery systems yielded higher γSLW, γS+ and γS- but lower γSAB than the Poly-Pore delivery systems. Poly-Pore based delivery systems highly loaded with low surface tension active agents were found not to influence the physical properties but to significantly increase the water contact angle and thus reduce surface free energy of dental resin composites.

  14. [Dental prostheses and dental impressions from a hygienic viewpoint].

    Science.gov (United States)

    Engelhardt, J P

    1986-12-01

    Dentures, dental impressions, removable orthodontic appliances and all dental technical devices, which are part of any dental treatment are parts as well of a potential crosscontamination chain in dental treatment. Most of those items do not tolerate heat as a sure sterilization medium. For disinfection, chemical disinfectant solutions may be used as far as they work properly and as they are tolerated by the materials in question. Though, one can report some progress in disinfection of dentures and impressions, there are still questions open depending on safety and/or compatibility of the particular materials. For disinfection of removable dentures chlorine-yielding preparations such as Maranon can be recommended. Peracid preparations, such as Sekusept, Sekusept steril and Dentavon may be useful for disinfection of dental impressions. To do the possible means to reduce the infection risk for all persons involved in the dental treatment, patient, dentist, dental technician and all auxiliary persons. This includes both, active hygiene provisions as sterilization and disinfection, as well as possible passive self protection.

  15. Development of the CEREC dental system and cutting materials%CEREC系统及切削材料进展

    Institute of Scientific and Technical Information of China (English)

    王林虎; 董青山; 马毅慧

    2012-01-01

    CEREC (chairside economical restoration of esthetic ceramic)是一种椅旁计算机辅助设计和计算机辅助制作(com-puter aided design/computer aided manufacturing,CAD/CAM)系统,它引领着牙科数字化发展方向.作为一种高便捷、高质量、高审美的的数字化牙科修复系统,吸引了无数牙医和患者的青睐,临床应用日趋广泛.文中就CEREC的CAD/CAM系统的发展过程、构成及工作原理、CEREC系统发展以及可切削材料改进作一综述.%The CEREC system is a chairside CAD/CAM (computer aided design /computer aided manufacturing) dental restoration system. It leads the dental digital development. As a high-convenient, high-quality, high-aesthetic digital dental restoration system, it attracts many dentists and patients to favor. There is an increasingly wide range of its clinical application. This article describes the development of the CEREC system, its work principle, the newest product of CEREC system and the cutting materials used to fabricate the restoration.

  16. The impact of three strains of oral bacteria on the surface and mechanical properties of a dental resin material.

    Science.gov (United States)

    Gregson, Karen S; Shih, Han; Gregory, Richard L

    2012-08-01

    The purpose of this study was to determine if three strains of bacteria could impact the mechanical or surface properties of a dental resin material. Resin material specimens were incubated at 37°C in sterile saline, tryptic soy broth supplemented with sucrose (TSBS), or TSBS inoculated with Streptococcus mutans, Streptococcus gordonii, or Streptococcus sanguis. The specimens were subjected to Fourier transform infrared spectroscopy before and after incubation. The flexural strength test was performed once a week for 6 weeks. Microhardness and scanning electron microscopy (SEM) was performed on specimens at 1 and 6 weeks. Differences in the area under the carbonyl peak were statistically significant for the specimens incubated in the media inoculated with either S. mutans or S. gordonii. To determine why S. sanguis did not produce changes as the other bacteria did, triethylene glycol dimethacrylate, methacrylic acid, and triethylene glycol were added to bacterial cultures at increasing concentrations. Both methacrylic acid and triethylene glycol reduced the number of colony-forming units of S. sanguis. Specimens incubated in TSBS, saline or in culture with S. sanguis demonstrated a decrease in peak stress in week 1 of the flexure strength test. SEM demonstrated that surface topology changed for those specimens incubated in culture with S. mutans or S. gordonii. The changes in surface topology demonstrated here could contribute to the secondary caries and changes in esthetic properties seen clinically with the use of resin materials in dental restorations.

  17. COMPARATIVE CHARACTERISTICS OF MATERIALS USED IN DENTAL IMPLANTATION

    Directory of Open Access Journals (Sweden)

    A. A. Yegorov

    2014-01-01

    Full Text Available The objective of the research is a review of some characteristics of dental implants’ products and an analysis of prospects of using them in modern medicine.Dental implantation as a high-technology method of restoring the natural anatomical structure has no competitors at present. The advantages of dental implants consist in their high operational dependability, a longer life time, a higher functionality and a lesser rate of complications as compared to the use of complete or bridge prostheses.The materials used in dental implantation for this purpose are rather diverse. Doctors using them rely on extensive clinical experience, a developed industry of accessory materials, instruments, that is everything that ensures comfortable work and conveniences for the patient.At the same time, the data mentioned in the article testify to the effect that ceramic implants as compared to titanium alloy implants have comparable or better indices. This is guaranteed, for example, by the requirements of the new international standard ISO6474-2:2012: first-rate strength and wear resistance; thermal stability and corrosion resistance; ceramics’ four point bending strength over 750 MPa.The result of the conducted analysis is a review of using various materials in dental implantation. The author compares the aesthetic indices and durability of titanium or metal alloy implants to those of ceramic ones. The comparison shows that, under the current level of ceramic materials’ structural property, it is actual for dentistry to develop its own methodological approaches in relation to a wide use of ceramic implants and creation of various ceramic mono-implants with the purpose of improving the results of treatment of patients, suffering from secondary partial or complete adentia accompanied by bone tissue deficiency, by applying the methods of dental implantation.

  18. Biomedical Biopolymers, their Origin and Evolution in Biomedical Sciences: A Systematic Review.

    Science.gov (United States)

    Yadav, Preeti; Yadav, Harsh; Shah, Veena Gowri; Shah, Gaurav; Dhaka, Gaurav

    2015-09-01

    Biopolymers provide a plethora of applications in the pharmaceutical and medical applications. A material that can be used for biomedical applications like wound healing, drug delivery and tissue engineering should possess certain properties like biocompatibility, biodegradation to non-toxic products, low antigenicity, high bio-activity, processability to complicated shapes with appropriate porosity, ability to support cell growth and proliferation and appropriate mechanical properties, as well as maintaining mechanical strength. This paper reviews biodegradable biopolymers focusing on their potential in biomedical applications. Biopolymers most commonly used and most abundantly available have been described with focus on the properties relevant to biomedical importance.

  19. Developing Customized Dental Miniscrew Surgical Template from Thermoplastic Polymer Material Using Image Superimposition, CAD System, and 3D Printing

    Directory of Open Access Journals (Sweden)

    Yu-Tzu Wang

    2017-01-01

    Full Text Available This study integrates cone-beam computed tomography (CBCT/laser scan image superposition, computer-aided design (CAD, and 3D printing (3DP to develop a technology for producing customized dental (orthodontic miniscrew surgical templates using polymer material. Maxillary bone solid models with the bone and teeth reconstructed using CBCT images and teeth and mucosa outer profile acquired using laser scanning were superimposed to allow miniscrew visual insertion planning and permit surgical template fabrication. The customized surgical template CAD model was fabricated offset based on the teeth/mucosa/bracket contour profiles in the superimposition model and exported to duplicate the plastic template using the 3DP technique and polymer material. An anterior retraction and intrusion clinical test for the maxillary canines/incisors showed that two miniscrews were placed safely and did not produce inflammation or other discomfort symptoms one week after surgery. The fitness between the mucosa and template indicated that the average gap sizes were found smaller than 0.5 mm and confirmed that the surgical template presented good holding power and well-fitting adaption. This study addressed integrating CBCT and laser scan image superposition; CAD and 3DP techniques can be applied to fabricate an accurate customized surgical template for dental orthodontic miniscrews.

  20. Developing Customized Dental Miniscrew Surgical Template from Thermoplastic Polymer Material Using Image Superimposition, CAD System, and 3D Printing

    Science.gov (United States)

    Yu, Jian-Hong; Lo, Lun-Jou; Hsu, Pin-Hsin

    2017-01-01

    This study integrates cone-beam computed tomography (CBCT)/laser scan image superposition, computer-aided design (CAD), and 3D printing (3DP) to develop a technology for producing customized dental (orthodontic) miniscrew surgical templates using polymer material. Maxillary bone solid models with the bone and teeth reconstructed using CBCT images and teeth and mucosa outer profile acquired using laser scanning were superimposed to allow miniscrew visual insertion planning and permit surgical template fabrication. The customized surgical template CAD model was fabricated offset based on the teeth/mucosa/bracket contour profiles in the superimposition model and exported to duplicate the plastic template using the 3DP technique and polymer material. An anterior retraction and intrusion clinical test for the maxillary canines/incisors showed that two miniscrews were placed safely and did not produce inflammation or other discomfort symptoms one week after surgery. The fitness between the mucosa and template indicated that the average gap sizes were found smaller than 0.5 mm and confirmed that the surgical template presented good holding power and well-fitting adaption. This study addressed integrating CBCT and laser scan image superposition; CAD and 3DP techniques can be applied to fabricate an accurate customized surgical template for dental orthodontic miniscrews. PMID:28280726

  1. Biomedical engineering for health research and development.

    Science.gov (United States)

    Zhang, X-Y

    2015-01-01

    Biomedical engineering is a new area of research in medicine and biology, providing new concepts and designs for the diagnosis, treatment and prevention of various diseases. There are several types of biomedical engineering, such as tissue, genetic, neural and stem cells, as well as chemical and clinical engineering for health care. Many electronic and magnetic methods and equipments are used for the biomedical engineering such as Computed Tomography (CT) scans, Magnetic Resonance Imaging (MRI) scans, Electroencephalography (EEG), Ultrasound and regenerative medicine and stem cell cultures, preparations of artificial cells and organs, such as pancreas, urinary bladders, liver cells, and fibroblasts cells of foreskin and others. The principle of tissue engineering is described with various types of cells used for tissue engineering purposes. The use of several medical devices and bionics are mentioned with scaffold, cells and tissue cultures and various materials are used for biomedical engineering. The use of biomedical engineering methods is very important for the human health, and research and development of diseases. The bioreactors and preparations of artificial cells or tissues and organs are described here.

  2. Fifty years of Brazilian Dental Materials Group: scientific contributions of dental materials field evaluated by systematic review

    OpenAIRE

    Wellington Luiz de Oliveira ROSA; Tiago Machado SILVA; Lima, Giana da Silveira; SILVA, Adriana Fernandes; Piva,Evandro

    2016-01-01

    ABSTRACT Objective A systematic review was conducted to analyze Brazilian scientific and technological production related to the dental materials field over the past 50 years. Material and Methods This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (Prisma) statement. Searches were performed until December 2014 in six databases: MedLine (PubMed), Scopus, LILACS, IBECS, BBO, and the Cochrane Library. Additionally, the Brazilian patent database (INPI -...

  3. Injectable hydrogels as unique biomedical materials.

    Science.gov (United States)

    Yu, Lin; Ding, Jiandong

    2008-08-01

    A concentrated fish soup could be gelled in the winter and re-solled upon heating. In contrast, some synthetic copolymers exhibit an inverse sol-gel transition with spontaneous physical gelation upon heating instead of cooling. If the transition in water takes place below the body temperature and the chemicals are biocompatible and biodegradable, such gelling behavior makes the associated physical gels injectable biomaterials with unique applications in drug delivery and tissue engineering etc. Various therapeutic agents or cells can be entrapped in situ and form a depot merely by a syringe injection of their aqueous solutions at target sites with minimal invasiveness and pain. This tutorial review summarizes and comments on this soft matter, especially thermogelling poly(ethylene glycol)-(biodegradable polyester) block copolymers. The main types of injectable hydrogels are also briefly introduced, including both physical gels and chemical gels.

  4. An interview study of persons who attribute health problems to dental filling materials--part two in a triangulation study on 65 and 75 years old Swedes.

    Science.gov (United States)

    Ståhlnacke, Katri; Söderfeldt, Björn

    2013-01-01

    Dental materials are perceived as a health problem by some people, although scientists do not agree about possible causes of such problems. The aim of this paper was to gain a deeper knowledge and understanding of experiences from living with health problems attributed to dental materials. Addressed topics were the type of problem, both as to general and oral health, perceived causes of the problems,their experienced effect on life, and reception by health professionals. Persons, who in a previous large questionnaire study had answered that they had experienced troubles from dental materials and also agreed to answer follow-up questions, were contacted with a request to take part in an interview study. Eleven individual interviews were held.The interviews were transcribed verbatim and the material was analysed according to the Qualitative Content Analysis method. Meaning units were extracted and condensed into a number of codes, which were combined into subcategories, categories, and themes. Four themes were identified: 1) Long-term oral, mental, and somatic difficulties of varying character, caused by dental amalgam. 2) Problems treated mainly by replacement of dental material in fillings. 3) Powerful effects on life, mostly negative. 4) The reception by health professionals was generally good, but with elements of encounters where they felt treated with nonchalance and lack of respect. In conclusion, people who attributed their health difficulties to dental materials had a complex range of problems and the perception was that amalgam/mercury was the cause of the troubles. The reception from health professionals was perceived as generally good, although with occasional negative experiences.

  5. Marginal adaptation and performance of bioactive dental restorative materials in deciduous and young permanent teeth

    Directory of Open Access Journals (Sweden)

    Elizabeta Gjorgievska

    2008-02-01

    Full Text Available OBJECTIVE: The aim of this study was to investigate the adaptation of different types of restorations towards deciduous and young permanent teeth. MATERIAL AND METHODS: Class V cavities were prepared in deciduous and young permanent teeth and filled with different materials (a conventional glass-ionomer, a resin-modified glass-ionomer, a poly-acid-modified composite resin and a conventional composite resin. Specimens were aged in artificial saliva for 1, 6, 12 and 18 months, then examined by SEM. RESULTS: The composite resin and the polyacid-modified composite had better marginal adaptation than the glass-ionomers, though microcracks developed in the enamel of the tooth. The glass-ionomers showed inferior marginal quality and durability, but no microcracking of the enamel. The margins of the resin-modified glass-ionomer were slightly superior to the conventional glass-ionomer. Conditioning improved the adaptation of the composite resin, but the type of tooth made little or no difference to the performance of the restorative material. All materials were associated with the formation of crystals in the gaps between the filling and the tooth; the quantity and shape of these crystals varied with the material. CONCLUSIONS: Resin-based materials are generally better at forming sound, durable margins in deciduous and young permanent teeth than cements, but are associated with microcracks in the enamel. All fluoride-releasing materials give rise to crystalline deposits.

  6. Biomedical Imaging Principles and Applications

    CERN Document Server

    Salzer, Reiner

    2012-01-01

    This book presents and describes imaging technologies that can be used to study chemical processes and structural interactions in dynamic systems, principally in biomedical systems. The imaging technologies, largely biomedical imaging technologies such as MRT, Fluorescence mapping, raman mapping, nanoESCA, and CARS microscopy, have been selected according to their application range and to the chemical information content of their data. These technologies allow for the analysis and evaluation of delicate biological samples, which must not be disturbed during the profess. Ultimately, this may me

  7. Dielectric and electric properties of new chitosan-hydroxyapatite materials for biomedical application: Dielectric spectroscopy and corona treatment.

    Science.gov (United States)

    Petrov, Ivo; Kalinkevich, Oksana; Pogorielov, Maksym; Kalinkevich, Aleksei; Stanislavov, Aleksandr; Sklyar, Anatoly; Danilchenko, Sergei; Yovcheva, Temenuzhka

    2016-10-20

    Chitosan-hydroxyapatite composite materials were synthesized and the possibility to make their surface charged by corona discharge treatment has been evaluated. Dielectric and electric properties of the materials were studied by dielectric spectroscopy, including application of equivalent circuits method and computer simulations. Dielectric spectroscopy shows behavior of the materials quite different from that of both chitosan and HA alone. The obtained dielectric permittivity data are of particular interest in predicting the materials' behavior in electrostimulation after implantation. The ε values observed at physiological temperature in the frequency ranges applied are similar to ε data available for bone tissues.

  8. Marginal adaptation and performance of bioactive dental restorative materials in deciduous and young permanent teeth.

    OpenAIRE

    Elizabeta Gjorgievska; John W. Nicholson; Snezana Iljovska; Slipper, Ian J.

    2008-01-01

    Objective: The aim of this study was to investigate the adaptation of different types of restorations towards deciduous and young permanent teeth. Materials and Methods: Class V cavities were prepared in deciduous and young permanent teeth and filled with different materials (a conventional glass-ionomer, a resin-modified glass-ionomer, a poly-acid-modified composite resin and a conventional composite resin). Specimens were aged in artificial saliva for 1, 6, 12 and 18 months, then examined b...

  9. Bacteriostatic and anti-collagenolytic dental materials through the incorporation of polyacrylic acid modified CuI nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Renne, Walter George; Mennito, Anthony Samuel; Schmidt, Michael Gerard; Vuthiganon, Jompobe; Chumanov, George

    2015-05-19

    Provided are antibacterial and antimicrobial surface coatings and dental materials by utilizing the antimicrobial properties of copper chalcogenide and/or copper halide (CuQ, where Q=chalcogens including oxygen, or halogens, or nothing). An antimicrobial barrier is created by incorporation of CuQ nanoparticles of an appropriate size and at a concentration necessary and sufficient to create a unique bioelectrical environment. The unique bioelectrical environment results in biocidal effectiveness through a multi-factorial mechanism comprising a combination of the intrinsic quantum flux of copper (Cu.sup.0, Cu.sup.1+, Cu.sup.2+) ions and the high surface-to-volume electron sink facilitated by the nanoparticle. The result is the constant quantum flux of copper which manifests and establishes the antimicrobial environment preventing or inhibiting the growth of bacteria. The presence of CuQ results in inhibiting or delaying bacterial destruction and endogenous enzymatic breakdown of the zone of resin inter-diffusion, the integrity of which is essential for dental restoration longevity.

  10. Obtaining New Dental Materials Reinforced with Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    I.V. Zaporotskova

    2014-07-01

    Full Text Available The article seeks to explore the change of strength properties of composite polymer material on the basis of fast-hardening dental plastic "Carbogen", when reinforcing its coal-native nanotubes. Were discussed peculiarities of composition of Carboante, ways of creation of polymeric composition deposits by doping their carbon nanotubes, the results of measuring the strength characteristic characteristics obtained new polymer materials. On the basis of the analysis of the practical and the theoretical-sky research, conclusions were drawn on the feasibility of a new filling material with the use of carbon nanotubes with unique strength characteristics and use of their in dentistry.

  11. Engineering artificial machines from designable DNA materials for biomedical applications.

    Science.gov (United States)

    Qi, Hao; Huang, Guoyou; Han, Yulong; Zhang, Xiaohui; Li, Yuhui; Pingguan-Murphy, Belinda; Lu, Tian Jian; Xu, Feng; Wang, Lin

    2015-06-01

    Deoxyribonucleic acid (DNA) emerges as building bricks for the fabrication of nanostructure with complete artificial architecture and geometry. The amazing ability of DNA in building two- and three-dimensional structures raises the possibility of developing smart nanomachines with versatile controllability for various applications. Here, we overviewed the recent progresses in engineering DNA machines for specific bioengineering and biomedical applications.

  12. Application and safety evaluation of different dental implant materials%不同口腔种植材料的应用及安全性评价

    Institute of Scientific and Technical Information of China (English)

    宣永华

    2011-01-01

    背景:目前临床应用的牙种植体材料种类繁多,各有其优缺点,哪种材料更具临床应用价值及良好的生物相容性呢? 目的:综述不同口腔种植材料的研究进展,评价其种植后与宿主的相容性及临床应用前景.方法:应用计算机检索CNKI和PubMed数据库中2000-01/2011-03关于口腔种植材料应用的文章,在标题和摘要中以"口腔种植体;牙种植体;合金;陶瓷;高分子材料;复合材料"或"dental implant;polymer alloy composite material;ceramic/aluminum alloy"为检索词进行检索.选择内容与不同口腔种植材料的应用特点及安全性相关文章.初检得到126篇文献,根据纳入标准选择30篇文章进行综述.结果与结论:合金、陶瓷、高分子、复合材料及纳米材料在口腔种植方面发挥了重要作用.理想口腔植入材料的选择,需要对其生物相容性、生物力学性能、生物学形态、与周围组织的结合能力等各方面综合考虑,对细胞、组织等应无毒性、无刺激性、无致畸致突变性,同时与骨组织之间应形成骨性结合,具有良好的骨引导或骨诱导作用.%BACKGROUND: Currently, clinical dental implant materials are various with their own advantages and disadvantages, which one is better in clinical application and has good biocompatibility?OBJECTIVE: To review the progress of different dental implant materials and to evaluate the compatibility of dental implants with the host as well as their clinical prospect.METHODS: CNKI and PubMed (2000-01/2011-03) were retrieved for articles addressing application of dental implant materials using the keywords of “dental implant; polymer alloy composite material; ceramic/aluminum alloy” in English anddental implant;tooth implant; alloy; ceramic; polymer material; composite material” in Chinese. Articles about application characteristics of different dental implant materials and their safety were retrieved and 126 articles were found

  13. Artifacts by dental materials on magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Hyun Sook; Choi, Deuk Lin; Kim, Ki Jung [Soonchunhyang University Hospital, Asan (Korea, Republic of); Suh, Won Hyuck [Korea University Hospital, Seoul (Korea, Republic of)

    1992-05-15

    Magnetic resonance imaging (MRI) has proved to be a valuable method for evaluation of the head and neck. Unfortunately, metallic devices associated with certain dental fillings and appliances often cause variable artifacts that can obscure normal or pathologic conditions on MR and computed tomography. In this work, we assessed the MR appearance of dental prosthetic materials in vitro and in vivo including precious alloys, nonprecions alloys, resin, amalgam and titanium alloy. For in vivo studies, these materials were placed in healthy volunteer's mouths and then images were assessed. Analysis of the appearance of shape and extent of artifact, and observed influence of these artifacts on the image interpretation at 0.2 Tesla permanent type MR scanner were valuated. Material used as temporary or permanent filling of crowns such as amalgam, precious alloy and, microfilled resin did not cause artifact on the image. The size of the artifact produced by the nonprecious alloys was influenced by the ferromagnetism of the object and the volume prosthesis, and was related to the scanning sequence. Nonprecious alloys produced minimal local signal distortion, where precious alloys, and dental resin had no effect on the MR images in vivo. These results were mainly from a low field strength MR scanner used in this study.

  14. In vitro and in vivo studies of ultrafine-grain Ti as dental implant material processed by ECAP.

    Science.gov (United States)

    An, Baili; Li, Zhirui; Diao, Xiaoou; Xin, Haitao; Zhang, Qiang; Jia, Xiaorui; Wu, Yulu; Li, Kai; Guo, Yazhou

    2016-10-01

    The aim of this study was to investigate the surface characterization of ultrafine-grain pure titanium (UFG-Ti) after sandblasting and acid-etching (SLA) and to evaluate its biocompatibility as dental implant material in vitro and in vivo. UFG-Ti was produced by equal channel angular pressing (ECAP) using commercially pure titanium (CP-Ti). Microstructure and yield strength were investigated. The morphology, wettability and roughness of the specimens were analyzed after they were modified by SLA. MC3T3-E1 osteoblasts were seeded onto the specimens to evaluate its biocompatibility in vitro. For the in vivo study, UFG-Ti implants after SLA were embedded into the femurs of New Zealand rabbits. Osseointegration was investigated though micro-CT analysis, histological assessment and pull-out test. The control group was CP-Ti. UFG-Ti with enhanced mechanical properties was produced by four passes of ECAP in BC route at room temperature. After SLA modification, the hierarchical porous structure on its surface exhibited excellent wettability. The adhesion, proliferation and viability of cells cultured on the UFG-Ti were superior to that of CP-Ti. In the in vivo study, favorable osseointegration occurred between the implant and bone in CP and UFG-Ti groups. The combination intensity of UF- Ti with bone was higher according to the pull-out test. This study supports the claim that UFG-Ti has grain refinement with outstanding mechanical properties and, with its excellent biocompatibility, has potential for use as dental implant material.

  15. Education About Dental Hygienists' Roles in Public Dental Prevention Programs: Dental and Dental Hygiene Students' and Faculty Members' and Dental Hygienists' Perspectives.

    Science.gov (United States)

    Pervez, Anushey; Kinney, Janet S; Gwozdek, Anne; Farrell, Christine M; Inglehart, Marita R

    2016-09-01

    In 2005, Public Act No. 161 (PA 161) was passed in Michigan, allowing dental hygienists to practice in approved public dental prevention programs to provide services for underserved populations while utilizing a collaborative agreement with a supervising dentist. The aims of this study were to assess how well dental and dental hygiene students and faculty members and practicing dental hygienists have been educated about PA 161, what attitudes and knowledge about the act they have, and how interested they are in additional education about it. University of Michigan dental and dental hygiene students and faculty members, students in other Michigan dental hygiene programs, and dental hygienists in the state were surveyed. Respondents (response rate) were 160 dental students (50%), 63 dental hygiene students (82%), 30 dental faculty members (26%), and 12 dental hygiene faculty members (52%) at the University of Michigan; 143 dental hygiene students in other programs (20%); and 95 members of the Michigan Dental Hygienists' Association (10%). The results showed that the dental students were less educated about PA 161 than the dental hygiene students, and the dental faculty members were less informed than the dental hygiene faculty members and dental hygienists. Responding dental hygiene faculty members and dental hygienists had more positive attitudes about PA 161 than did the students and dental faculty members. Most of the dental hygiene faculty members and dental hygienists knew a person providing services in a PA 161 program. Most dental hygiene students, faculty members, and dental hygienists wanted more education about PA 161. Overall, the better educated about the program the respondents were, the more positive their attitudes, and the more interested they were in learning more.

  16. Carbon-Based Nanomaterials: Multi-Functional Materials for Biomedical Engineering

    Science.gov (United States)

    Cha, Chaenyung; Shin, Su Ryon; Annabi, Nasim; Dokmeci, Mehmet R.; Khademhosseini, Ali

    2013-01-01

    Functional carbon-based nanomaterials (CBNs) have become important due to their unique combinations of chemical and physical properties (i.e., thermal and electrical conductivity, high mechanical strength, and optical properties), extensive research efforts are being made to utilize these materials for various industrial applications, such as high-strength materials and electronics. These advantageous properties of CBNs are also actively investigated in several areas of biomedical engineering. This Perspective highlights different types of carbon-based nanomaterials currently used in biomedical applications. PMID:23560817

  17. National Institute of Biomedical Imaging and Bioengineering

    Science.gov (United States)

    ... Health & Human Services National Institutes of Health Creating Biomedical Technologies to Improve Health En Español | Site Map | ... 2016 VIEW MORE NEWS AND HIGHLIGHTS Design by Biomedical Undergraduate Teams Challenge RSS LISTSERV YOUTUBE FACEBOOK TWITTER ...

  18. Ex vivo and in vitro synchrotron-based micro-imaging of biocompatible materials applied in dental surgery

    Science.gov (United States)

    Rack, A.; Stiller, M.; Nelson, K.; Knabe, C.; Rack, T.; Zabler, S.; Dalügge, O.; Riesemeier, H.; Cecilia, A.; Goebbels, J.

    2010-09-01

    Biocompatible materials such as porous bioactive calcium phosphate ceramics or titanium are regularly applied in dental surgery: ceramics are used to support the local bone regeneration in a given defect, afterwards titanium implants replace lost teeth. The current gold standard for bone reconstruction in implant dentistry is the use of autogenous bone grafts. But the concept of guided bone regeneration (GBR) has become a predictable and well documented surgical approach using biomaterials (bioactive calcium phosphate ceramics) which qualify as bone substitutes for this kind of application as well. We applied high resolution synchrotron microtomography and subsequent 3d image analysis in order to investigate bone formation and degradation of the bone substitute material in a three-dimensional manner, extending the knowledge beyond the limits of classical histology. Following the bone regeneration, titanium-based implants to replace lost teeth call for high mechanical precision, especially when two-piece concepts are used in order to guaranty leak tightness. Here, synchrotron-based radiography in comparison with classical laboratory radiography yields high spatial resolution in combination with high contrast even when exploiting micro-sized features in these kind of highly attenuating objects. Therefore, we could study micro-gap formation at interfaces in two-piece dental implants with the specimen under different mechanical load. We could prove the existence of micro-gaps for implants with conical connections as well as to study the micromechanical behavior of the mating zone of conical implants during loading. The micro-gap is a potential issue of failure, i. e. bacterial leakage which can induce an inflammatory process.

  19. A Qualitative Evaluation of the Views of Community Workers on the Dental Health Education Material Available in New South Wales for Culturally and Linguistically Diverse Communities

    Science.gov (United States)

    Blinkhorn, Anthony; Gittani, Jamily

    2009-01-01

    Objective: To record the views of individuals whose main professional role is community liaison on dental health education material for culturally and linguistically diverse communities. Methods: Tape-recorded interviews were undertaken, reviewed by two individuals and themes identified. Results: Twenty four individuals were interviewed out of a…

  20. Health promotion and dental caries.

    Science.gov (United States)

    Maltz, Marisa; Jardim, Juliana Jobim; Alves, Luana Severo

    2010-01-01

    The central idea of the Brazilian health system is to prevent the establishment of disease or detect it as early as possible. Prevention and treatment of dental caries are related to behavioral factors, including dietary and oral hygiene habits, which are related to many chronic diseases. Dental health promotion therefore should be fully integrated into broadly based health-promoting strategies and actions such as food and health policies, and general hygiene (including oral hygiene), among others. For decades, a linear relationship between sugar consumption and caries has been observed. Recent data has indicated that this relationship is not as strong as it used to be before the widespread use of fluoride. However, diet is still a key factor acting in the carious process. Oral hygiene is a major aspect when it comes to caries, since dental biofilm is its etiological factor. Oral hygiene procedures are effective in controlling dental caries, especially if plaque removal is performed adequately and associated with fluoride. An alternative to a more efficient biofilm control in occlusal areas is the use of dental sealants, which are only indicated for caries-active individuals. If a cavity is formed as a consequence of the metabolic activity of the biofilm, a restorative material or a sealant can be placed to block access of the biofilm to the oral environment in order to prevent caries progress. The prevention of dental caries based on common risk-factor strategies (diet and hygiene) should be supplemented by more disease-specific policies such as rational use of fluoride, and evidence-based dental health care.

  1. Health promotion and dental caries

    Directory of Open Access Journals (Sweden)

    Marisa Maltz

    2010-01-01

    Full Text Available The central idea of the Brazilian health system is to prevent the establishment of disease or detect it as early as possible. Prevention and treatment of dental caries are related to behavioral factors, including dietary and oral hygiene habits, which are related to many chronic diseases. Dental health promotion therefore should be fully integrated into broadly based health-promoting strategies and actions such as food and health policies, and general hygiene (including oral hygiene, among others. For decades, a linear relationship between sugar consumption and caries has been observed. Recent data has indicated that this relationship is not as strong as it used to be before the widespread use of fluoride. However, diet is still a key factor acting in the carious process. Oral hygiene is a major aspect when it comes to caries, since dental biofilm is its etiological factor. Oral hygiene procedures are effective in controlling dental caries, especially if plaque removal is performed adequately and associated with fluoride. An alternative to a more efficient biofilm control in occlusal areas is the use of dental sealants, which are only indicated for caries-active individuals. If a cavity is formed as a consequence of the metabolic activity of the biofilm, a restorative material or a sealant can be placed to block access of the biofilm to the oral environment in order to prevent caries progress. The prevention of dental caries based on common risk-factor strategies (diet and hygiene should be supplemented by more disease-specific policies such as rational use of fluoride, and evidence-based dental health care.

  2. Inorganic nanolayers: structure, preparation, and biomedical applications

    Science.gov (United States)

    Saifullah, Bullo; Hussein, Mohd Zobir B

    2015-01-01

    Hydrotalcite-like compounds are two-dimensional inorganic nanolayers also known as clay minerals or anionic clays or layered double hydroxides/layered hydroxy salts, and have emerged as a single type of material with numerous biomedical applications, such as drug delivery, gene delivery, cosmetics, and biosensing. Inorganic nanolayers are promising materials due to their fascinating properties, such as ease of preparation, ability to intercalate different type of anions (inorganic, organic, biomolecules, and even genes), high thermal stability, delivery of intercalated anions in a sustained manner, high biocompatibility, and easy biodegradation. Inorganic nanolayers have been the focus for researchers over the last decade, resulting in widening application horizons, especially in the field of biomedical science. These nanolayers have been widely applied in drug and gene delivery. They have also been applied in biosensing technology, and most recently in bioimaging science. The suitability of inorganic nanolayers for application in drug delivery, gene delivery, biosensing technology, and bioimaging science makes them ideal materials to be applied for theranostic purposes. In this paper, we review the structure, methods of preparation, and latest advances made by inorganic nanolayers in such biomedical applications as drug delivery, gene delivery, biosensing, and bioimaging. PMID:26366081

  3. Inorganic nanolayers: structure, preparation, and biomedical applications.

    Science.gov (United States)

    Saifullah, Bullo; Hussein, Mohd Zobir B

    2015-01-01

    Hydrotalcite-like compounds are two-dimensional inorganic nanolayers also known as clay minerals or anionic clays or layered double hydroxides/layered hydroxy salts, and have emerged as a single type of material with numerous biomedical applications, such as drug delivery, gene delivery, cosmetics, and biosensing. Inorganic nanolayers are promising materials due to their fascinating properties, such as ease of preparation, ability to intercalate different type of anions (inorganic, organic, biomolecules, and even genes), high thermal stability, delivery of intercalated anions in a sustained manner, high biocompatibility, and easy biodegradation. Inorganic nanolayers have been the focus for researchers over the last decade, resulting in widening application horizons, especially in the field of biomedical science. These nanolayers have been widely applied in drug and gene delivery. They have also been applied in biosensing technology, and most recently in bioimaging science. The suitability of inorganic nanolayers for application in drug delivery, gene delivery, biosensing technology, and bioimaging science makes them ideal materials to be applied for theranostic purposes. In this paper, we review the structure, methods of preparation, and latest advances made by inorganic nanolayers in such biomedical applications as drug delivery, gene delivery, biosensing, and bioimaging.

  4. Updating Classifications of Ceramic Dental Materials: A Guide to Material Selection.

    Science.gov (United States)

    McLaren, Edward A; Figueira, Johan

    2015-06-01

    The indications for and composition of today's dental ceramic materials serve as the basis for determining the appropriate class of ceramics to use for a given case. By understanding the classifications, composition, and characteristics of the latest all-ceramic materials, which are presented in this article in order of most to least conservative, dentists and laboratory technicians can best determine the ideal material for a particular treatment.

  5. Xilitol and dental caries.

    NARCIS (Netherlands)

    Smits, Marten Titus

    1987-01-01

    Dental caries is a widespread multifactoral disease. The main sympthons are minaral loss from tooth enemal and dentine, eventually leading to total destruction of the teeth, pain, impairment of mastication and problems with facial esthetics. ... Zie: Summary

  6. Determination of dose rates from natural radionuclides in dental materials

    Energy Technology Data Exchange (ETDEWEB)

    Veronese, I. [Dipartimento di Fisica, Universita degli Studi di Milano, Milan (Italy) and INFN, Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Milan (Italy)]. E-mail: ivan.veronese@unimi.it; Guzzi, G. [AIRMEB - Italian Association for Metal and Biocompatibility Research, Milan (Italy); Giussani, A. [Dipartimento di Fisica, Universita degli Studi di Milano, Milan (Italy); INFN, Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Milan (Italy); Cantone, M.C. [Dipartimento di Fisica, Universita degli Studi di Milano, Milan (Italy); INFN, Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Milan (Italy); Ripamonti, D. [Dipartimento di Fisica, Universita degli Studi di Milano, Milan (Italy)

    2006-07-01

    Different types of materials used for dental prosthetics restoration, including feldspathic ceramics, glass ceramics, zirconia-based ceramics, alumina-based ceramics, and resin-based materials, were investigated with regard to content of natural radionuclides by means of thermoluminescence beta dosimetry and gamma spectrometry. The gross beta dose rate from feldspathic and glass ceramics was about ten times higher than the background measurement, whereas resin-based materials generated negligible beta dose rate, similarly to natural tooth samples. The specific activity of uranium and thorium was significantly below the levels found in the period when addition of uranium to dental porcelain materials was still permitted. The high-beta dose levels observed in feldspathic porcelains and glass ceramics are thus mainly ascribable to {sup 4}K, naturally present in these specimens. Although the measured values are below the recommended limits, results indicate that patients with prostheses are subject to higher dose levels than other members of the population. Alumina- and zirconia-based ceramics might be a promising alternative, as they have generally lower beta dose rates than the conventional porcelain materials. However, the dosimetry results, which imply the presence of inhomogeneously distributed clusters of radionuclides in the sample matrix, and the still unsuitable structural properties call for further optimization of these materials.

  7. Embryotoxicity assays for leached components from dental restorative materials

    Directory of Open Access Journals (Sweden)

    Mummolo Stefano

    2011-10-01

    Full Text Available Abstract Background Currently, there are no suitable assays available to evaluate the embryotoxicity of leached components from restorative dental materials. Methods The effect of the medium conditioned by composites and amalgam on mouse blastocysts in vitro was tested. The materials were also subcutaneously implanted, and the effect of the medium supplemented with serum from the host blood was evaluated in the embryotoxicity assay. The embryo implantation rate in the material-transplanted mothers was also evaluated. Results The results show that while the culture in media conditioned by amalgams did not affect blastocyst development, the medium conditioned by composites caused blastocyst degeneration and apoptosis. The development of blastocysts in a medium containing serum obtained from animals after transplantation was, however, without effect. Finally, inconsistent reduction in the implantation rate in transplanted mothers was observed. Conclusions In this study, we provide examples of in vitro and in vivo tests that may be used to evaluate embryotoxicity for dental materials. Our results show that leached components from our composite-material induced embryotoxicity in vitro, however, no toxicity was observed when subcutaneously implanted in vivo. This highlights the necessity of integrated in vitro and in vivo tests for valuable predictive estimation of embryotoxicity for complex materials.

  8. Surface detail reproduction of Type IV dental stones with selected polyvinyl siloxane impression materials.

    Science.gov (United States)

    Schelb, E; Cavazos, E; Troendle, K B; Prihoda, T J

    1991-01-01

    Four polyvinyl siloxane impression materials and 14 modified Type IV dental stones were evaluated for their abilities to reproduce surface detail. Each combination of impression material and dental stone was used to duplicate a 20-microns-wide line. Surface detail reproduction was observed by two paired-rater groups. The line was reproduced in all impression material specimens, but in only 32% of the stone cast specimens. Some combinations of impression material/dental stone reproduced the line all or most of the time, but 12 combinations did not reproduce the line at all.

  9. Terahertz biomedical science and technology

    CERN Document Server

    Son, Joo-Hiuk

    2014-01-01

    Introduction to Biomedical Studies Using Terahertz WavesJoo-Hiuk SonSection I Terahertz TechnologyTerahertz Sources and DetectorsHyunyong Choi and Joo-Hiuk SonTabletop High-Power Terahertz Pulse Generation TechniquesYun-Shik LeeTerahertz Imaging and Tomography TechniquesHyunyong Choi and Joo-Hiuk SonCompact Solid-State Electronic Terahertz Devices and CircuitsJae-Sung Rieh, Daekeun Yoon, and Jongwon Yun<

  10. Dosimetric consideration for patients with dental filling materials undergoing irradiation of oral cavity using RapidArc: challenges and solution

    Science.gov (United States)

    Mail, Noor; Albarakati, Y.; Khan, M. Ahmad; Saeedi, F.; Safadi, N.; Al-Ghamdi, S.; Saoudi, A.

    2012-03-01

    In this study, we investigate the effect of dental filling materials (DFM) on RapidArcTM treatment plans and delivery in a patient undergoing radiotherapy treatment. The presence of DFM creates uncertainties in CT number and causes long streaking artifacts in the reconstructed images which greatly affect the dose distribution inside the oral cavity. The influence of extensive dental filling artifacts on dose distribution was performed using a geometrically well defined head and neck IMRT verification phantom (PTW, Freiburg, Germany) together with inserts from DFM (Amalgam, 11.3 g/cm3). The phantom was scanned using Siemens SOMATOM Sensation CT simulator (Siemens AG, Germany) under standard head and neck imaging protocol (120 kV, 120 mAs, voxel size 1×1×2 mm3). Three RapidArcTM plans were created in the Varian Eclipse treatment planning System (TPS) to treat oral cavity using the same CT dataset including; 1) raw CT image, 2) streaking artifacts replaced with a mask of 10 HU and 3) 2 cm thick 6000 HU virtual filter (a volume around the teeth in TPS to mimic extra attenuation). The virtual filter thickness optimization was purely based on measured PDD data acquired with DFM and the calculation in Eclipse Planning System using direct beam. The dose delivery and distribution for the three plans was verified using Gafchromic EBT2 (International Specialty Product, Wayne, NJ, USA) film measurements. The artifact mask and virtual filter around the teeth in the planning was found very useful to reduce the discrepancies between the dose plan and delivery. From clinical point of view, these results can be helpful to understand the increase of mucositis in patient having DFM, and further investigation is underway for clinical solution.

  11. [Dental ceramics: its history and development].

    Science.gov (United States)

    Moureau, Thomas; Vanheusden, Alain

    2006-01-01

    This article presents an historical background of dental ceramics. It synthesises the evolution of such material and its technical improvements from the stone-age to our time. Focusing on the importance of dental aesthetics, it shows the investigations realised to upgrade the prosthetic results.

  12. Biomedical devices and their applications

    CERN Document Server

    2004-01-01

    This volume introduces readers to the basic concepts and recent advances in the field of biomedical devices. The text gives a detailed account of novel developments in drug delivery, protein electrophoresis, estrogen mimicking methods and medical devices. It also provides the necessary theoretical background as well as describing a wide range of practical applications. The level and style make this book accessible not only to scientific and medical researchers but also to graduate students.

  13. The impacts of dental filling materials on RapidArc treatment planning and dose delivery: Challenges and solution

    Energy Technology Data Exchange (ETDEWEB)

    Mail, Noor; Al-Ghamdi, S.; Saoudi, A. [Princess Norah Oncology Center, National Guard Health Affairs, Jeddah 21423, Saudi Arabia and King Abdullah International Medical Research Center, Jeddah 21423 (Saudi Arabia); Albarakati, Y.; Ahmad Khan, M.; Saeedi, F.; Safadi, N. [Princess Norah Oncology Center, National Guard Health Affairs, Jeddah 21423 (Saudi Arabia)

    2013-08-15

    Purpose: The presence of high-density material in the oral cavity creates dose perturbation in both downstream and upstream directions at the surfaces of dental filling materials (DFM). In this study, the authors have investigated the effect of DFM on head and neck RapidArc treatment plans and delivery. Solutions are proposed to address (1) the issue of downstream dose perturbation, which might cause target under dosage, and (2) to reduce the upstream dose from DFM which may be the primary source of mucositis. In addition, an investigation of the clinical role of a custom-made plastic dental mold/gutter (PDM) in sparing the oral mucosa and tongue reaction is outlined.Methods: The influence of the dental filling artifacts on dose distribution was investigated using a geometrically well-defined head and neck intensity modulated radiation therapy (IMRT) verification phantom (PTW, Freiberg, Germany) with DFM inserts called amalgam, which contained 50% mercury, 25% silver, 14% tin, 8% copper, and 3% other trace metals. Three RapidArc plans were generated in the Varian Eclipse System to treat the oral cavity using the same computer tomography (CT) dataset, including (1) a raw CT image, (2) a streaking artifacts region, which was replaced with a mask of 10 HU, and (3) a 2 cm-thick 6000 HU virtual filter [a volume created in treatment planning system to compensate for beam attenuation, where the thickness of this virtual filter is based on the measured percent depth dose (PDD) data and Eclipse calculation]. The dose delivery for the three plans was verified using Gafchromic-EBT2 film measurements. The custom-made PDM technique to reduce backscatter dose was clinically tested on four head and neck cancer patients (T3, N1, M0) with DFM, two patients with PDM and the other two patients without PDM. The thickness calculation of the PDM toward the mucosa and tongue was purely based on the measured upstream dose. Patients’ with oral mucosal reaction was clinically examined

  14. Bone remodeling induced by dental implants of functionally graded materials.

    Science.gov (United States)

    Lin, Daniel; Li, Qing; Li, Wei; Swain, Michael

    2010-02-01

    Functionally graded material (FGM) had been developed as a potential implant material to replace titanium for its improved capability of initial osseointegration. The idea behind FGM dental implant is that its properties can be tailored in accordance with the biomechanical needs at different regions adapting to its hosting bony tissues, therefore creating an improved overall integration and stability in the entire restoration. However, there have been very few reports available so far on predicting bone remodeling induced by FGM dental implants. This article aims to evaluate bone remodeling when replacing the titanium with a hydroxyapatite/collagen (HAP/Col) FGM model. A finite element model was constructed in the buccal-lingual section of a dental implant-bone structure generated from in vivo CT scan images. The remodeling simulation was performed over a 4 year healing period. Comparisons were made between the titanium implant and various FGM implants of this model. The FGM implants showed an improved bone remodeling outcome. The study is expected to provide a basis for future development of FGM implants.

  15. Depth of cure of dental resin composites: ISO 4049 depth and microhardness of types of materials and shades.

    Science.gov (United States)

    Moore, B Keith; Platt, Jeffrey A; Borges, Gilberto; Chu, Tien-Min Gabriel; Katsilieri, Iphigenia

    2008-01-01

    The optimal degree of curing throughout the bulk of a visible light-activated dental resin composite is acknowledged to be important to the clinical success of a resin composite restoration. Unfortunately, the dentist has no means of monitoring the cure of the resin surfaces not directly exposed to the curing light. Techniques, such as the layered buildup of restorations in 2 mm increments with longer activation times than 20 seconds, have been suggested. This study investigated the depth of cure (DOC) of a commercial resin composite in three types: flowable, hybrid and packable and in three shades: B1, A3 and D3 after 20 second activation with a quartz halogen light (620 mW/cm2). Depth of cure was measured by scraping the uncured material and by using a Knoop Hardness profile, starting from the surface exposed to the light. Using a minimum Knoop Hardness ratio of 0.8 bottom/top only, the flowable in shade B1 achieved a 2 mm DOC. Using the less restrictive scraping test, only the B1 shade of flowable and hybrid significantly exceeded a 2 mm DOC. Knoop Hardness at the DOC obtained by scraping ranged from 55%-70% of the top surface hardness. These data suggest that a 2 mm buildup layering technique may not result in adequate curing of the bottom layer for such a wide range of materials and that manufacturers need to provide quantitative information about DOC at specific activation times and light intensities for their entire range of resin materials and shades so that the dentist can devise a placement technique that will ensure adequate cure of the bulk of a restoration.

  16. Synthesis and characterizations of a fluoride-releasing dental restorative material.

    Science.gov (United States)

    Khan, Abdul Samad; Aamer, Sidra; Chaudhry, Aqif Anwar; Wong, Ferranti S L; Ur Rehman, Ihtesham

    2013-08-01

    The aim was to develop an obturating material which has the tendency to release fluoride and minimize interfaces with tooth. Nano-fluorapatite (nFA) powder was synthesized by sol-gel. The composite based on polyurethane (PU) was obtained by chemically binding the nFA (10, 15, 20%wt/wt) to the diisocyanate component by utilizing in-situ polymerization. The procedure involved stepwise addition of monomeric units of PU, and optimizing the reagent concentrations to synthesize composite. The structural, phase and morphological analysis of nFA was evaluated. The structural, fluoride release and in-vitro adhesion analysis with tooth structure of PU/nFA was conducted. For fluoride release analysis the samples were stored in artificial saliva and deionized water for periodical time intervals. Bond strength of composites was analyzed by push-out test. Chemical linkage was achieved between PU and nFA without intermediate coupling agent. The insignificant difference of fluoride release pattern was observed in artificial saliva and (p≥0.05) deionized water. The PU/nFA composite provided sustained release of fluoride over a long period of time. The composite showed more adhesion toward tooth structure with the increase in concentration of nFA. Bond strength of composite was in accordance with root canal filling material, hence, the material with anti-cariogenic properties can be used as an obturating material.

  17. Biomedical ethics and the biomedical engineer: a review.

    Science.gov (United States)

    Saha, S; Saha, P S

    1997-01-01

    Biomedical engineering is responsible for many of the dramatic advances in modern medicine. This has resulted in improved medical care and better quality of life for patients. However, biomedical technology has also contributed to new ethical dilemmas and has challenged some of our moral values. Bioengineers often lack adequate training in facing these moral and ethical problems. These include conflicts of interest, allocation of scarce resources, research misconduct, animal experimentation, and clinical trials for new medical devices. This paper is a compilation of our previous published papers on these topics, and it summarizes many complex ethical issues that a bioengineer may face during his or her research career or professional practice. The need for ethics training in the education of a bioengineering student is emphasized. We also advocate the adoption of a code of ethics for bioengineers.

  18. The Relationship between Biofilm and Physical-Chemical Properties of Implant Abutment Materials for Successful Dental Implants

    Directory of Open Access Journals (Sweden)

    Erica Dorigatti de Avila

    2014-05-01

    Full Text Available The aim of this review was to investigate the relationship between biofilm and peri-implant disease, with an emphasis on the types of implant abutment surfaces. Individuals with periodontal disease typically have a large amount of pathogenic microorganisms in the periodontal pocket. If the individuals lose their teeth, these microorganisms remain viable inside the mouth and can directly influence peri-implant microbiota. Metal implants offer a suitable solution, but similarly, these remaining bacteria can adhere on abutment implant surfaces, induce peri-implantitis causing potential destruction of the alveolar bone near to the implant threads and cause the subsequent loss of the implant. Studies have demonstrated differences in biofilm formation on dental materials and these variations can be associated with both physical and chemical characteristics of the surfaces. In the case of partially edentulous patients affected by periodontal disease, the ideal type of implant abutments utilized should be one that adheres the least or negligible amounts of periodontopathogenic bacteria. Therefore, it is of clinically relevance to know how the bacteria behave on different types of surfaces in order to develop new materials and/or new types of treatment surfaces, which will reduce or inhibit adhesion of pathogenic microorganisms, and, thus, restrict the use of the abutments with indication propensity for bacterial adhesion.

  19. Educational material of dental anatomy applied to study the morphology of permanent teeth.

    Science.gov (United States)

    Siéssere, Selma; Vitti, Mathias; de Sousa, Luiz Gustavo; Semprini, Marisa; Regalo, Simone Cecílio Hallak

    2004-01-01

    The purpose of this report is to present educational material that would allow the dental student to learn to easily identify the morphologic characteristics of permanent teeth, and how they fit together (occlusion). In order to do this, macro models of permanent teeth with no attrition were carved in wax and later molded with alginate. These molds were filled with plaster, dental stone and/or cold-cured acrylic resin. The large individual dental stone tooth models were mounted on a wax base, thus obtaining maxillary and mandibular arches which were occluded. These dental arches were molded with plaster or dental stone. The authors suggest that these types of macro models allow an excellent visualization of the morphologic characteristics of permanent teeth and occlusion. Dental students are able to carve the permanent dentition in wax with great facility when they can observe macro models.

  20. Health Instruction Packages: Permanent Teeth, Dental Deposits, and Dental Instruments. Dientes Permanentes, Depositos Dentales y Instrumentos Dentales.

    Science.gov (United States)

    Lind, Patricia; Germano, Catherine

    These five learning modules use text interspersed with illustrations and reinforcement exercises to instruct dental aide and dental hygiene students about jaw bones and gums, dental deposits, and dental instruments. The first four modules were prepared by Patricia Lind in both Spanish and English. "The Gum and Bone of Permanent Teeth"…

  1. Survey on the teaching and use in dental schools of resin-based materials for restoring posterior teeth.

    Science.gov (United States)

    Liew, Zunliang; Nguyen, Edward; Stella, Rita; Thong, Irene; Yip, Natalia; Zhang, Felix; Burrow, Michael F; Tyas, Martin J

    2011-02-01

    A survey was conducted of 100 dental schools worldwide to investigate the current teaching of posterior resin composite restorations. A 20 multi-part question questionnaire was emailed to the selected schools. Schools were selected by ability to understand and respond in English. The questionnaire consisted of four open-ended questions and 16 closed questions on topics such as material selection for restoring posterior teeth, preclinical teaching of resin composite for posterior teeth, restoration size, contraindications, matrix placement methods, lining use, adhesive selection and finishing. Forty-six schools responded. The outcomes showed all schools included the teaching of resin composite for posterior restorations but varied. The majority of schools (63%) no longer taught amalgam as the preferred posterior restorative material. Half of the schools surveyed set numerical clinical requirements for restoration placement. Australian schools had no requirements whilst 92% of Asian schools did. There was a consensus that larger restorations were less suitable for resin composite. Selection of adhesives depended on region. Generally, the schools surveyed showed minor variations philosophically in teaching of the use and placement of resin composite restorations.

  2. Equity in children’s dental caries before and after cessation of community water fluoridation: differential impact by dental insurance status and geographic material deprivation

    OpenAIRE

    McLaren, Lindsay; McNeil, Deborah A; Potestio, Melissa; Patterson, Steve; Thawer, Salima; Faris, Peter; Shi, Congshi; Shwart, Luke

    2016-01-01

    Background One of the main arguments made in favor of community water fluoridation is that it is equitable in its impact on dental caries (i.e., helps to offset inequities in dental caries). Although an equitable effect of fluoridation has been demonstrated in cross-sectional studies, it has not been studied in the context of cessation of community water fluoridation (CWF). The objective of this study was to compare the socio-economic patterns of children’s dental caries (tooth decay) in Calg...

  3. MICROWAVE PROPAGATION IN TOOTH AND DENTAL DEFECT

    Directory of Open Access Journals (Sweden)

    Maria Papezova

    2016-09-01

    Full Text Available INTRODUCTION:The most common method of conventional dental diagnosisinvolves X-rays, such as Radio Tomography (RT or Computer Tomography (CT. Such methods are used for diagnosing pores in dental material that can lead to premature failure of dental material. Diagnosis by X-ray provides an objective analysis. However, repeated radiation from X-rays can cause biological damage to human tissues. From this point of view, there is a significant need to progress to quantitative non-invasive and non-destructive testing (NDT methods to measure dental material and improve treatment options. This article focuses on applying microwave technology to characterize teeth and teeth replacements. Knowledge of microwave propagation in biomaterial with no defects, using a defined microwave frequency range, and subsequently comparing the result with defective material could provide a means of dental diagnosis without the risk of radiation for the patient, i.e. without X-ray. OBJECTIVES: The primary objective of this study was to examine microwave technology in the field of dental medical diagnosis as a new NDT method. METHODS: The basic concept of applying microwave technology to characterize teeth in dental diagnosis was examined using a basic algorithm designed in the MATLAB programming language. Tests used dielectric properties of tooth and tooth decay and propagated electromagnetic (EM waves to show different characteristics of chosen materials.RESULTS: The analyses of frequency dependent reflection and transmission coefficients of the chosen material, specificallyteeth, atfrequency range 0 GHz to 30 GHz, computed differences between healthy and defective dental material.CONCLUSION: Thus, this could be used in providing a dental diagnosis without exposing patients to radiation, i.e. without X-ray. The next stage will involve creating a complete model of a jaw with teeth, and designing a sensor for crack detection for comparisons using this basic algorithm.

  4. In vitro and in vivo studies of ultrafine-grain Ti as dental implant material processed by ECAP

    Energy Technology Data Exchange (ETDEWEB)

    An, Baili; Li, Zhirui; Diao, Xiaoou [State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi' an 710032 (China); National Clinical Research Center for Oral Diseases, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi' an 710032 (China); Shannxi Key Laboratory of Oral Diseases, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi' an 710032 (China); Xin, Haitao, E-mail: xhthmj@fmmu.edu.cn [State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi' an 710032 (China); National Clinical Research Center for Oral Diseases, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi' an 710032 (China); Shannxi Key Laboratory of Oral Diseases, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi' an 710032 (China); Zhang, Qiang; Jia, Xiaorui; Wu, Yulu; Li, Kai [State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi' an 710032 (China); National Clinical Research Center for Oral Diseases, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi' an 710032 (China); Shannxi Key Laboratory of Oral Diseases, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi' an 710032 (China); Guo, Yazhou [School of Aeronautics, Northwestern Polytechnical University, Xi' an 710032 (China)

    2016-10-01

    The aim of this study was to investigate the surface characterization of ultrafine-grain pure titanium (UFG-Ti) after sandblasting and acid-etching (SLA) and to evaluate its biocompatibility as dental implant material in vitro and in vivo. UFG-Ti was produced by equal channel angular pressing (ECAP) using commercially pure titanium (CP-Ti). Microstructure and yield strength were investigated. The morphology, wettability and roughness of the specimens were analyzed after they were modified by SLA. MC3T3-E1 osteoblasts were seeded onto the specimens to evaluate its biocompatibility in vitro. For the in vivo study, UFG-Ti implants after SLA were embedded into the femurs of New Zealand rabbits. Osseointegration was investigated though micro-CT analysis, histological assessment and pull-out test. The control group was CP-Ti. UFG-Ti with enhanced mechanical properties was produced by four passes of ECAP in B{sub C} route at room temperature. After SLA modification, the hierarchical porous structure on its surface exhibited excellent wettability. The adhesion, proliferation and viability of cells cultured on the UFG-Ti were superior to that of CP-Ti. In the in vivo study, favorable osseointegration occurred between the implant and bone in CP and UFG-Ti groups. The combination intensity of UF- Ti with bone was higher according to the pull-out test. This study supports the claim that UFG-Ti has grain refinement with outstanding mechanical properties and, with its excellent biocompatibility, has potential for use as dental implant material. - Highlights: • Yield strength and Vickers hardness of Ti are improved significantly after it is grain-refined by ECAP process. • The hierarchical micro-porous structure with superior wettability could be formed on the surface of ECAP Ti after SLA. • The results in vitro exhibited excellent cell biocompatibility of UFG-Ti after sandblasting and acid-etching. • The osseointegration between UFG-Ti implant and surrounding bone could

  5. In vitro study of biofilm formation and effectiveness of antimicrobial treatment on various dental material surfaces.

    Science.gov (United States)

    Li, L; Finnegan, M B; Özkan, S; Kim, Y; Lillehoj, P B; Ho, C-M; Lux, R; Mito, R; Loewy, Z; Shi, W

    2010-12-01

    Elevated proportions of Candida albicans in biofilms formed on dentures are associated with stomatitis whereas Streptococcus mutans accumulation on restorative materials can cause secondary caries. Candida albicans, S. mutans, saliva-derived and C. albicans/saliva-derived mixed biofilms were grown on different materials including acrylic denture, porcelain, hydroxyapatite (HA), and polystyrene. The resulting biomass was analysed by three-dimensional image quantification and assessment of colony-forming units. The efficacy of biofilm treatment with a dissolved denture cleansing tablet (Polident(®)) was also evaluated by colony counting. Biofilms formed on HA exhibited the most striking differences in biomass accumulation: biofilms comprising salivary bacteria accrued the highest total biomass whereas C. albicans biofilm formation was greatly reduced on the HA surface compared with other materials, including the acrylic denture surface. These results substantiate clinical findings that acrylic dentures can comprise a reservoir for C. albicans, which renders patients more susceptible to C. albicans infections and stomatitis. Additionally, treatment efficacy of the same type of biofilms varied significantly depending on the surface. Although single-species biofilms formed on polystyrene surfaces exhibited the highest susceptibility to the treatment, the most surviving cells were recovered from HA surfaces for all types of biofilms tested. This study demonstrates that the nature of a surface influences biofilm characteristics including biomass accumulation and susceptibility to antimicrobial treatments. Such treatments should therefore be evaluated on the surfaces colonized by the target pathogen(s).

  6. Cytogenetic Evaluation of the Physiological Saline Extract of a Newly Developed Dental Material "ORMO-48".

    Science.gov (United States)

    Mohanan, P V; Mol, Lizzy

    2011-07-01

    The ORMO-48 is a new indigenous material for dental applications, developed by the Dental Products Laboratory of our Institute. The aim of the present study was to evaluate the genotoxic effect of an indigenously developed dental material in Swiss albino mice. The genotoxic effect was evaluated by micronucleus and chromosomal aberration tests. Two grams of dental material was extracted in 10.0 ml of physiological saline at 70°C for 24 h. The extract was cooled to room temperature and was used for the experiment. The experimental designed had three groups each (six mice in each group) for micronucleus and chromosomal aberration tests. The first, second, and third groups were given a single exposure of physiological saline alone (control), dental material's extract (test), and cyclophosphamide (positive control) respectively for micronucleus and chromosomal aberration tests. The result of the study indicated that, the percentage of micronucleated PCE (polychromatic erythrocytes) and NCE (normochromatic erythrocytes) induced by the dental material (extract) treated group was well comparable with control group, whereas the positive control induced significantly high (P dental material extract treated group was similar to that of control group. The chromosomal anomalies such as chromatid/chromosomal breaks, centric rings, exchanges, dicentric, and acentric fragments were evaluated. The result showed that the anomalies of the dental material extract treated group were similar to control group, however, significant anomalies were observed in the cyclophosphamide treated group. Hence, the present study concluded that the indigenously developed biocompatible dental material, ORMO-48 is non genotoxic at our laboratory conditions.

  7. Survey of attitudes, materials and methods employed in endodontic treatment by general dental practitioners in North Jordan

    Directory of Open Access Journals (Sweden)

    Al-Omari Wael M

    2004-09-01

    Full Text Available Abstract Background General dental practitioners provide the majority of endodontic treatment in Jordan. The aim of this study was to gather information on the methods, materials and attitudes employed in root canal treatment by dentists in North Jordan, in order to evaluate and improve the quality of current practice. Methods A questionnaire was posted to all registered general dental practitioners working in private practice in Irbid Governate in North Jordan (n = 181. The questionnaire included information on methods, materials and techniques used in endodontic treatment. Results Reply rate was 72% (n = 131. The results demonstrated that only five dentists used rubber dam occasionally and not routinely. The majority used cotton rolls for isolation solely or in combination with a high volume saliva ejector (n = 116. The most widely used irrigants were sodium hypochlorite and hydrogen peroxide, which were used by 32.9% (n = 43 and 33.6% (n = 44 of the respondents, respectively. Forty eight percent of the respondents (n = 61 used the cold lateral condensation technique for canal obturation, 31.3% (n = 41 used single cone, 9.9% (n = 13 used vertical condensation and 12.2% (n = 16 used paste or cement only for the obturation. The majority used zinc oxide eugenol as a sealer (72.5%. All, but one, respondents used hand instruments for canal preparation and the technique of choice was step back (52.7%. More than 50% (n = 70 of the dentists took one radiograph for determining the working length, whilst 22.9% (n = 30 did not take any radiograph at all. Most practitioners performed treatment in three visits for teeth with two or more root canals, and in two visits for teeth with a single root canal. Conclusions This study indicates that dentists practicing in North Jordan do not comply with international quality standards and do not use recently introduced techniques. Many clinicians never take a radiograph for determining the working length and never

  8. Mechanical characterization of materials for dental applications; Caracterizacion mecanica de materiales para aplicaciones dentales

    Energy Technology Data Exchange (ETDEWEB)

    Pajares, A.; Miranda, P.; Guiberteau, F.; Cumbrera, F. I.

    2001-07-01

    An study of the damage induced in dental materials and model multilayer systems by masticatory contact stresses, simulated by hertz ian indentation test, have been performed. In particular, the nature of induced damage has been identified, and quantified from stress-strain curves and critical loads for yielding or crack initiation. For multilayer systems, test have been numerically simulated using finite element techniques (FEM). FEM simulations complement indentation test, allowing to justify the observed fracture modes from calculated stress fields. Practical implications can be derived from our results, relevant to the design of multilayer structures tolerant to contact damage. (Author) 34 refs.

  9. Comparative Studies of Electrospinning and Solution Blow Spinning Processes for the Production of Nanofibrous Poly(L-Lactic Acid Materials for Biomedical Engineering

    Directory of Open Access Journals (Sweden)

    Wojasiński Michal

    2014-06-01

    Full Text Available Comparative statistical analysis of the infiuence of processing parameters, for electrospinning (ES and solution blow spinning (SBS processes, on nanofibrous poly(L-lactic acid (PLLA material morphology and average fiber diameter was conducted in order to identify the key processing parameter for tailoring the product properties. Further, a comparative preliminary biocompatibility evaluation was performed. Based on Design of Experiment (DOE principles, analysis of standard effects of voltage, air pressure, solution feed rate and concentration, on nanofibers average diameter was performed with the Pareto’s charts and the best fitted surface charts. Nanofibers were analyzed by scanning electron microscopy (SEM. The preliminary biocompatibility comparative tests were performed based on SEM microphotographs of CP5 cells cultured on materials derived from ES and SBS. Polymer solution concentration was identified as the key parameter infiuencing morphology and dimensions of nanofibrous mat produced from both techniques. In both cases, when polymer concentration increases the average fiber diameter increase. The preliminary biocompatibility test suggests that nanofibers produced by ES as well as SBS are suitable as the biomedical engineering scaffold material.

  10. Bulimia and Anorexia Nervosa in Dental and Dental Hygiene Curricula.

    Science.gov (United States)

    Gross, Karen B. W.; And Others

    1990-01-01

    Dentists and dental hygienists are in a unique position to identify an eating disorder patient from observed oral manifestations and to refer the patient for psychological therapy. The inclusion of information on general and oral complications of bulimia and anorexia nervosa in dental and dental hygiene curriculum was examined. (MLW)

  11. Biomedical signal and image processing

    CERN Document Server

    Najarian, Kayvan

    2012-01-01

    INTRODUCTION TO DIGITAL SIGNAL AND IMAGE PROCESSINGSignals and Biomedical Signal ProcessingIntroduction and OverviewWhat is a ""Signal""?Analog, Discrete, and Digital SignalsProcessing and Transformation of SignalsSignal Processing for Feature ExtractionSome Characteristics of Digital ImagesSummaryProblemsFourier TransformIntroduction and OverviewOne-Dimensional Continuous Fourier TransformSampling and NYQUIST RateOne-Dimensional Discrete Fourier TransformTwo-Dimensional Discrete Fourier TransformFilter DesignSummaryProblemsImage Filtering, Enhancement, and RestorationIntroduction and Overview

  12. Preliminary validation of handheld X-ray fluorescence spectrometry: distinguishing osseous and dental tissue from nonbone material of similar chemical composition.

    Science.gov (United States)

    Zimmerman, Heather A; Schultz, John J; Sigman, Michael E

    2015-03-01

    One of the tasks of a forensic anthropologist is to sort human bone fragments from other materials, which can be difficult when dealing with highly fragmented and taphonomically modified material. The purpose of this research is to develop a method using handheld X-ray fluorescence (HHXRF) spectrometry to distinguish human and nonhuman bone/teeth from nonbone materials of similar chemical composition using multivariate statistical analyses. The sample materials were derived primarily from previous studies: human bone and teeth, nonhuman bone, nonbiological materials, nonbone biological materials, and taphonomically modified materials. The testing included two phases, testing both the reliability of the instrument and the accuracy of the technique. The results indicate that osseous and dental tissue can be distinguished from nonbone material of similar chemical composition with a high degree of accuracy (94%). While it was not possible to discriminate rock apatite and synthetic hydroxyapatite from bone/teeth, this technique successfully discriminated ivory and octocoral.

  13. Effect of gamma irradiation on fluoride release and antibacterial activity of resin dental materials

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Fabiola Galbiatti de; Fucio, Suzana Beatriz Portugal de; Correr-Sobrinho, Lourenco [Universidade Estadual de Campinas (UNICAMP), Piracicaba, SP (Brazil). Piracicaba Dental School. Dept. of Dental Materials; Pascon, Fernanda Miori; Kantovitz, Kamila Rosamilia; Puppin-Rontani, Regina Maria [Universidade Estadual de Campinas (UNICAMP), Piracicaba, SP (Brazil). Piracicaba Dental School. Dept. of Pedriatric Dentistry], e-mail: rmpuppin@fop.unicamp.br

    2009-07-01

    This study evaluated the effect of gamma irradiation on fluoride release and antibacterial activity of FluroShield (FS) and Clearfil Protect Bond (CPB). Four groups were formed: G1-FS + gamma; G2-FS without gamma; G3-CPB + gamma; G4-CPB without gamma. For fluoride release analysis, 12 disks of each material were prepared and covered with nail polish, except for one side (50.4 mm{sup 2} area). G1 and G3 were sterilized with a 14.5 KGy dose at 27 deg C for 24 h, while G2 and G4 (controls) were not sterilized and were maintained under the same time and temperature conditions. Fluoride release measurements were made in duplicate (n=6) by an ion specific electrode. The antibacterial activity of the CPB and FS against Streptococcus mutans after gamma sterilization was evaluated by the agar-disc diffusion method. The diameter of the zones of microbial growth inhibition was recorded after 48 h. Data were analyzed statistically by ANOVA and Tukey's test (alpha=5%). Gamma sterilization decreased the fluoride release of FS by approximately 50%, while CPB was not affected. There was no statistically significant difference (p>0.05) in the antibacterial effect of CPB between gamma and non-gamma sterilization groups. FS presented no antibacterial activity. Gamma irradiation decreased the fluoride release of FS, but did not affect the antibacterial activity of the studied materials. (author)

  14. Evaluation of conventional and digital radiography capacities for distinguishing dental materials on radiograms depending on the present radiopacifying agent

    Directory of Open Access Journals (Sweden)

    Antonijević Đorđe

    2014-01-01

    Full Text Available Bacgroun/Aim. The radiopacity of an endodontic material can considerably vary as measured on film and a digital sensor. Digital radiography offers numerous advantages over convential film-based radiography in dental clinical practice regarding both diagnostic capabilities and postintervention procedures. The aim of this study was to investigate the capacity of conventional and charge-conpled device (CCD based digital radiography to detect material on radiograph depending on the radio-pacifying agent present in the material. Methods. Experimental cements were formulated by mixing Portland cement with the following radiopacifying agents: zinc oxide (ZnO, zirconium oxide (ZrO2, titanium dioxide (TiO2, barium sulphate (BaSO4, iodoform (CHI3, bismuth oxide (Bi2O3 and ytterbium trifluoride (YbF3. In addition, 5 endodontic materials comprising Endomethasone®, Diaket®, N2®, Roth 801® and Acroseal® were investigated to serve as control. Per three specimens of each material were radiographed alongside an aluminum step wedge on film (Eastman Kodak Company®, Rochester, NY and a CCD-based digital sensor (Trophy Radiologie®, Cedex, France. Radiopacity values were calculated by converting the radiographic densities of the specimens expressed as a mean optical densities or mean grey scale values into equivalent thickness of aluminum. Results. Twoway ANOVA detected no significant differences with respect to the imaging system (p > 0.05, but the differences were significant with respect to radiopacifier (p < 0.001 and the interaction of the two factors (p < 0.05. Paired ttest revealed significant differences between the methods used for pure Portland cement, all concentrations of BaSO4 and CHI3, 10% and 20% additions of ZrO2 and Bi2O3 and 10% and 30% addition of YbF3 (p < 0.05. Conclusion. The materials which incorporate CHI3 or BaSO4 as radiopacifying agents are expected to be significantly more radiopaque on a digital sensor than on film. During clinical

  15. Release and toxicity of dental resin composite

    OpenAIRE

    Saurabh K Gupta; Saxena, Payal; Pant, Vandana A.; Pant, Aditya B.

    2012-01-01

    Dental resin composite that are tooth-colored materials have been considered as possible substitutes to mercury-containing silver amalgam filling. Despite the fact that dental resin composites have improved their physico-chemical properties, the concern for its intrinsic toxicity remains high. Some components of restorative composite resins are released in the oral environment initially during polymerization reaction and later due to degradation of the material. In vitro and in vivo studies h...

  16. Blood Thinners and Dental Care

    Science.gov (United States)

    ... a Doctor Patient Condition Information Publications & News OOOO Journal Newsroom Clinicians’ Guides Clinical Practice Statements Newsletters Latest ... Meeting Orlando, FL Our Partners Blood Thinners and Dental Care Many dental patients are taking “blood thinner” ...

  17. Dental Care - Medicaid and Chip

    Data.gov (United States)

    U.S. Department of Health & Human Services — Dental health is an important part of peoples overall health. States are required to provide dental benefits to children covered by Medicaid and the Childrens Health...

  18. Dental operatory design and equipment.

    Science.gov (United States)

    Floyd, M

    1993-08-01

    Improving and expanding the dental services of a practice can involve purchasing new equipment and even modifying or expanding the physical plant. Operatory design is important to the efficiency with which dental procedures can be performed. Equipment purchases to outfit the dental operatory should be made based on the specific needs and functions of a practice.

  19. ENLIGHT and LEIR biomedical facility.

    Science.gov (United States)

    Dosanjh, M; Cirilli, M; Navin, S

    2014-07-01

    Particle therapy (including protons and carbon ions) allows a highly conformal treatment of deep-seated tumours with good accuracy and minimal dose to surrounding tissues, compared to conventional radiotherapy using X-rays. Following impressive results from early phase trials, over the last decades particle therapy in Europe has made considerable progress in terms of new institutes dedicated to charged particle therapy in several countries. Particle therapy is a multidisciplinary subject that involves physicists, biologists, radio-oncologists, engineers and computer scientists. The European Network for Light Ion Hadron Therapy (ENLIGHT) was created in response to the growing needs of the European community to coordinate such efforts. A number of treatment centres are already operational and treating patients across Europe, including two dual ion (protons and carbon ions) centres in Heidelberg (the pioneer in Europe) and Pavia. However, much more research needs to be carried out and beamtime is limited. Hence there is a strong interest from the biomedical research community to have a facility with greater access to relevant beamtime. Such a facility would facilitate research in radiobiology and the development of more accurate techniques of dosimetry and imaging. The Low Energy Ion Ring (LEIR) accelerator at CERN presents such an opportunity, and relies partly on CERN's existing infrastructure. The ENLIGHT network, European Commission projects under the ENLIGHT umbrella and the future biomedical facility are discussed.

  20. Frontiers in biomedical engineering and biotechnology.

    Science.gov (United States)

    Liu, Feng; Goodarzi, Ali; Wang, Haifeng; Stasiak, Joanna; Sun, Jianbo; Zhou, Yu

    2014-01-01

    The 2nd International Conference on Biomedical Engineering and Biotechnology (iCBEB 2013), held in Wuhan on 11–13 October 2013, is an annual conference that aims at providing an opportunity for international and national researchers and practitioners to present the most recent advances and future challenges in the fields of Biomedical Information, Biomedical Engineering and Biotechnology. The papers published by this issue are selected from this conference, which witnesses the frontier in the field of Biomedical Engineering and Biotechnology, which particularly has helped improving the level of clinical diagnosis in medical work.

  1. Dental ethics and emotional intelligence.

    Science.gov (United States)

    Rosenblum, Alvin B; Wolf, Steve

    2014-01-01

    Dental ethics is often taught, viewed, and conducted as an intell enterprise, uninformed by other noncognitive factors. Emotional intelligence (EQ) is defined distinguished from the cognitive intelligence measured by Intelligence Quotient (IQ). This essay recommends more inclusion of emotional, noncognitive input to the ethical decision process in dental education and dental practice.

  2. Cytotoxic Evaluation of Elastomeric Dental Impression Materials on a Permanent Mouse Cell Line and on a Primary Human Gingival Fibroblast Culture

    Directory of Open Access Journals (Sweden)

    Roberta Tiozzo

    2009-08-01

    Full Text Available The need for clinically relevant in vitro tests of dental materials is widely recognized. Nearly all dental impression materials are introduced into the mouth just after mixing and allowed to set in contact with the oral tissues. Under these conditions, the materials may be toxic to cells or may sensitize the tissues. The aim of the present study is to evaluate the potential cytotoxicity of new preparations of elastomeric dental impression materials: A four vinylpolysiloxanes: Elite H-D Putty and Elite H-D Light Body (Zhermack, Badia Polesine, Rovigo, Italy; Express Putty and Express Light Body (3M ESPE AG Seefeld, Germany and B two polyethers: Impregum Penta and Permadyne Penta L (3M ESPE AG Seefeld, Germany. The cytotoxicity of these impression materials were examined using two different cell lines: Balb/c 3T3 (permanent cell line and human gingival fibroblasts (primary cell line and their effects were studied by indirect and direct tests. The direct tests are performed by placing one sample of the impression materials in the centre of the Petri dishes at the time of the seeding of cells. The cell growth was evaluated at the 12th and 24th hours by cell number. The indirect tests were performed by incubating a square of 1 cm diameter impression material in 5 mL of medium at 37 °C for 24 hours (“eluates”. Subconfluent cultures are incubated with “eluates” for 24 hours. The MTT-formazan production is the method used for measuring the cell viability. The results indicate that: a polyether materials are cytotoxic under both experimental conditions; b among vinylpolysiloxanes, only Express Light Body (3M ESPE AG Seefeld, Germany induces clear inhibition of cellular viability of Balb/c 3T3 evaluated by direct and indirect tests and c the primary cell line is less sensitive to the toxic effect than the permanent cell line.

  3. In vitro toothbrushing abrasion of dental resin composites: packable, microhybrid, nanohybrid and microfilled materials

    Directory of Open Access Journals (Sweden)

    Rafael Ratto de Moraes

    2008-06-01

    Full Text Available This study evaluated weight loss and surface roughening after toothbrushing of different resin composites: one packable (Solitaire 2, Heraeus Kulzer, one microhybrid (Charisma, Heraeus Kulzer, one nanohybrid (Simile, Pentron and one microfilled (Durafill VS, Heraeus Kulzer. Cylindrical specimens (n = 20 were prepared. Half of the samples were submitted to 60,000 strokes, at 4 Hz, with a dentifrice-water slurry. Control samples (n = 10 remained stored at 37°C. Pre- and post-abrasion parameters for weight (mg and surface roughness (Ra, µm were determined on an analytical balance and a surface profilometer. Data were separately submitted to Repeated Measures ANOVA and Tukey's test (a = 0.05. Percentages of weight loss were analyzed by ANOVA and Tukey's test (a = 0.05. The relationship between both evaluations was assessed by Pearson's test (a = 0.05. The means (% for weight loss (standard deviation were 0.65(0.2, 0.93(0.2, 1.25(0.6 and 1.25(0.4 for Simile, Durafill, Charisma and Solitaire, respectively. Baseline roughness means ranged from 0.065(0.01, 0.071(0.01, 0.066(0.02 and 0.074(0.01 for Simile, Durafill, Charisma and Solitaire, respectively, to 0.105(0.04, 0.117(0.03, 0.161(0.03 and 0.214(0.07 after testing. The composites with larger fillers presented higher weight loss and roughening than the finer materials (p < 0.05. For both evaluations, control specimens showed no significant alteration. No significant relationship between loss of weight and roughness alteration was detected (r = 0.322, p = 0.429.

  4. USE OF PLASTIC MATERIAL AND TRIPLE SCAN IN THE PREPARATION OF SURGICAL GUIDES FOR THE DENTAL IMPLANT TREATMENT-CASE REPORT

    OpenAIRE

    Rosen Borisov

    2016-01-01

    The use of surgical guides in implant treatment increases the accuracy of the dental implant positioning compared with manual methods. Regardless of how they are made, deviations of implants from their intended position are established in all kinds of surgical guides. This article considers the use of plastic material and new scanning technique for the production of CAD/CAM surgical guides that aim to overcome the deficiencies of the currently applied technologies in the production of surgica...

  5. Developing Interactive Video Resource Materials for Community Dental Health.

    Science.gov (United States)

    Bartoli, Claire; And Others

    1986-01-01

    Describes the creation of a series of interactive video modules on dental hygiene at Luzerne County Community College. These modules are intended to supplement instruction in a community dentistry and health education course and to guide students in an assignment to develop and implement dental health projects in their community. (MBR)

  6. What constitutes an ideal dental restorative material?

    Science.gov (United States)

    Rekow, E D; Bayne, S C; Carvalho, R M; Steele, J G

    2013-11-01

    Intense environmental concerns recently have prompted dentistry to evaluate the performance and environmental impact of existing restoration materials. Doing so entices us to explore the 'what if?' innovation in materials science to create more ideal restorative materials. Articulating a specification for our design and evaluation methods is proving to be more complicated than originally anticipated. Challenges exist not only in specifying how the material should be manipulated and perform clinically but also in understanding and incorporating implications of the skill of the operator placing the restoration, economic considerations, expectations patients have for their investment, cost-effectiveness, influences of the health care system on how and for whom restorations are to be placed, and global challenges that limit the types of materials available in different areas of the world. The quandary is to find ways to actively engage multiple stakeholders to agree on priorities and future actions to focus future directions on the creation of more ideal restorative materials that can be available throughout the world.

  7. Mouth and dental disorders

    NARCIS (Netherlands)

    de Baat, C.; van der Waal, I.; Jackson, S.H.D.; Jansen, P.A.F.; Mangoni, A.A.

    2009-01-01

    Summary This chapter contains sections titled: • Introduction • Periodontal disease • Dental caries • Odontogenic infections • Alveolar osteitis • Xerostomia and hyposalivation • Candidiasis • Angular cheilitis • Denture stomatitis • Burning mouth syndrome • Recurrent aphthous stomatitis • Recurrent

  8. Biomedical wellness challenges and opportunities

    Science.gov (United States)

    Tangney, John F.

    2012-06-01

    The mission of ONR's Human and Bioengineered Systems Division is to direct, plan, foster, and encourage Science and Technology in cognitive science, computational neuroscience, bioscience and bio-mimetic technology, social/organizational science, training, human factors, and decision making as related to future Naval needs. This paper highlights current programs that contribute to future biomedical wellness needs in context of humanitarian assistance and disaster relief. ONR supports fundamental research and related technology demonstrations in several related areas, including biometrics and human activity recognition; cognitive sciences; computational neurosciences and bio-robotics; human factors, organizational design and decision research; social, cultural and behavioral modeling; and training, education and human performance. In context of a possible future with automated casualty evacuation, elements of current science and technology programs are illustrated.

  9. Scattering Anisotropy Measurements in Dental Tissues and Biomaterials

    Science.gov (United States)

    Fernandez-Oliveras, A.; Rubiño, M.; Perez, M. M.

    2012-05-01

    Understanding the behaviour of light propagation in biological materials is essential for biomedical engineering and applications, and even more so when dealing with incoming biomaterials. Many methods for determining optical parameters from biological media assume that scattered light is isotropically distributed over all angles. However, an angular dependence of light scattering may exist and affect the optical behaviour of biological media. The present work seeks to experimentally analyze the scattering anisotropy in different dental tissues (enamel and dentine) and their potential substitute biomaterials (hybrid dental-resin, nano-filled composite, and zirconia ceramic) and comparatively study them. Goniometric measurements were made for four wavelengths in the visible range, allowing a spectral characterization of the materials studied. Previously, for each material, measurements were made with two different sample thicknesses at the same wavelength, checking the behaviour of the angular scattering profile. The asymmetry of experimental phase functions was considered in the recovery of the scattering anisotropy factor. The results demonstrate that the thicker sample yielded a less forward-directed scattering profile than did the thinner sample. The biomaterials analysed show angular scattering comparable to those of the tissues that they may replace. Comparisons can be made by virtue of the low uncertainties found.

  10. A NEW METHOD TO PREPARE CHITOSAN MEMBRANE AS A BIOMEDICAL MATERIAL

    Institute of Scientific and Technical Information of China (English)

    Qiao-ling Hu; Zheng-ping Fang; YingZhao; Cheng-wei Xu

    2001-01-01

    This paper reports a new method to prepare chitosan membrane which could be used as a biomedical material.Addition of a fixation agent composed of alcohol, glycerol and potassium hydroxide can accelerate the sol-gel transformation process and hence shorten the preparation period. The present method takes about 6 h to get a flexible membrane with fine appearance. The physical and biological properties of the membrane were also investigated and compared with the membrane prepared by conventional method.``

  11. Dental anxiety and quality of life: the effect of dental treatment

    NARCIS (Netherlands)

    Vermaire, J.H.; de Jongh, A.; Aartman, I.H.A.

    2008-01-01

    Objective: The aim of the present study was to determine the association between dental anxiety and quality of life (QoL) and to test the hypothesis that treatment of highly anxious patients would significantly enhance QoL. Material and methods: Subjects were 35 highly anxious dental patients of a D

  12. Exploration of different school of thoughts among undergraduate dental students regarding dental caries and periodontal diseases

    Directory of Open Access Journals (Sweden)

    Anmol Mathur

    2015-01-01

    Full Text Available Introduction: The concepts about dental caries and periodontal diseases are learned at dental schools may directly influence the conduct of the future dentists regarding the control and treatment of these diseases. Aim: To assess the variation in the understanding of the concepts of dental caries and periodontal diseases among first to final year undergraduate dental students. Materials and Methods: A cross-sectional, questionnaire-based study was conducted among 400 students pursuing their graduation in a private dental college situated in Sri Ganganagar city, Rajasthan, India. Descriptive analysis was done, and Chi-square test with a significance level of 5% was done to compare the frequency based data. Results: For concepts related to dental caries, the 1st year students' response showed shift toward biological concept, which was also present for the 2nd year but the 3rd year onwards the majority of students cited the comprehensive multi-factorial concept (P = 0.0002. Final year students were more knowledgeable than the 1st, 2nd, and 3rd year students regarding gingival bleeding, swelling, redness, and bad breath being the most important signs of periodontal disease (P = 0.004. Conclusion: Significant variation in the school of thoughts and limited knowledge regarding the concepts of common dental diseases among dental undergraduate students is seen. There might be a need to reform the initial concept building methods utilized in dental institutions to improve the basic knowledge of undergraduate students of the common dental diseases.

  13. Cytogenetic Evaluation of the Physiological Saline Extract of a Newly Developed Dental Material “ORMO-48”

    OpenAIRE

    Mohanan, P. V.; Mol, Lizzy

    2011-01-01

    The ORMO-48 is a new indigenous material for dental applications, developed by the Dental Products Laboratory of our Institute. The aim of the present study was to evaluate the genotoxic effect of an indigenously developed dental material in Swiss albino mice. The genotoxic effect was evaluated by micronucleus and chromosomal aberration tests. Two grams of dental material was extracted in 10.0 ml of physiological saline at 70°C for 24 h. The extract was cooled to room temperature and was used...

  14. The addition of Si to the Ti–35Nb alloy and its effect on the corrosion resistance, when applied to biomedical materials

    Energy Technology Data Exchange (ETDEWEB)

    Tavares, A.M.G.; Fernandes, B.S.; Souza, S.A.; Batista, W.W.; Cunha, F.G.C. [Department of Materials Science and Engineering, Federal University of Sergipe, 49100-000 São Cristóvão, SE (Brazil); Landers, R. [Institute of Physics Gleb Wataghin, State University of Campinas – UNICAMP, 13083-859 Campinas, SP (Brazil); Macedo, M.C.S.S., E-mail: michellecardinales@gmail.com [Department of Materials Science and Engineering, Federal University of Sergipe, 49100-000 São Cristóvão, SE (Brazil)

    2014-04-05

    Highlights: • An investigation of the corrosion resistance of Ti–Nb–Si was proposed. • The study was based on polarization curves, OCP, electrochemical impedance, XPS. • The addition of Si to 0.35% increased the corrosion resistance of the alloys. • Data suggest that the studied alloys are promising for biomedical applications. -- Abstract: Alloy elements such as niobium and silicon have been added to titanium as an alternative for new materials to be used in orthopedic implants once they present biocompatibility and favor reductions in the elastic modulus. However, these new materials’ behavior, in face of corrosion is still demanding careful investigations because they will be subjected to an aggressive environ, such as the human body. The corrosion resistance of the Ti–35Nb–(0; 0.15; 0.35; 0.55)Si (% in mass) when in physiological medium was assessed by means of polarization curves, open circuit potential and electrochemical impedance spectroscopy. The compositions of the passive films were analyzed by X-ray photoelectron spectroscopy (XPS). Outcomes show that the alloys presented good rapid repassivation capacity after film breaking under high potentials. The high values of resistance to polarization – Rp – pinpoint that the formed oxide films are resistive. They work as a protecting barrier against aggressive ions. Data suggest that the studied alloys are promising for orthopedic implant applications.

  15. Advanced manufacturing of ceramics for biomedical applications: Subjection methods for biocompatible materials

    OpenAIRE

    Minguella Canela, Joaquim; Cuiñas, D; Uceda, Roger; Rodríguez, J. V.; Vivancos Calvet, Joan

    2013-01-01

    The continuously growing utilization of ceramic compounds in the field of medicine, industry and aerospace, among others, imply a high degree of specialization in terms of the material properties and functionalization due to the diversity of the requirements of the ceramic parts. The necessity of lightweight final parts with suitable surface properties oriented to biomedic applications demands innovative ceramic compounds whose machining is, in many cases, considerably difficult due to the fr...

  16. A rare allergy to a polyether dental impression material.

    Science.gov (United States)

    Mittermüller, Pauline; Szeimies, Rolf-Markus; Landthaler, Michael; Schmalz, Gottfried

    2012-08-01

    Polyether impression materials have been used in dentistry for more than 40 years. Allergic reactions to these materials such as reported in the 1970s ceased after replacement of a catalyst. Very recently, however, patients have started to report symptoms that suggest a new allergic reaction from polyether impression materials. Here, we report on the results of allergy testing with polyether impression materials as well as with its components. Eight patients with clinical symptoms of a contact allergy (swelling, redness or blisters) after exposure to a polyether impression material were subjected to patch tests, two of them additionally to a prick test. A further patient with atypical symptoms of an allergy (nausea and vomiting after contact with a polyether impression material in the oral cavity) but with a history of other allergic reaction was also patch tested. The prick tests showed no immediate reactions in the two patients tested. In the patch tests, all eight patients with typical clinical symptoms showed positive reactions to the mixed polyether impression materials, to the base paste or to a base paste component. The patient with the atypical clinical symptoms did not show any positive patch test reactions. Polyether impression materials may evoke type IV allergic reactions. The causative agent was a component of the base paste. In consideration of the widespread use of this impression material (millions of applications per year) and in comparison to the number of adverse reactions from other dental materials, the number of such allergic reactions is very low. In very scarce cases, positive allergic reactions to polyether impression materials are possible.

  17. Dental repair material: a resin-modified glass-ionomer bioactive ionic resin-based composite.

    Science.gov (United States)

    Croll, Theodore P; Berg, Joel H; Donly, Kevin J

    2015-01-01

    This report documents treatment and repair of three carious teeth that were restored with a new dental repair material that features the characteristics of both resin-modified glass-ionomer restorative cement (RMGI) and resin-based composite (RBC). The restorative products presented are reported by the manufacturer to be the first bioactive dental materials with an ionic resin matrix, a shock-absorbing resin component, and bioactive fillers that mimic the physical and chemical properties of natural teeth. The restorative material and base/liner, which feature three hardening mechanisms, could prove to be a notable advancement in the adhesive dentistry restorative materials continuum.

  18. Designing Multiagent Dental Materials for Enhanced Resistance to Biofilm Damage at the Bonded Interface.

    Science.gov (United States)

    Melo, Mary Anne; Orrego, Santiago; Weir, Michael D; Xu, Huakun H K; Arola, Dwayne D

    2016-05-11

    The oral environment is considered to be an asperous environment for restored tooth structure. Recurrent dental caries is a common cause of failure of tooth-colored restorations. Bacterial acids, microleakage, and cyclic stresses can lead to deterioration of the polymeric resin-tooth bonded interface. Research on the incorporation of cutting-edge anticaries agents for the design of new, long-lasting, bioactive resin-based dental materials is demanding and provoking work. Released antibacterial agents such as silver nanoparticles (NAg), nonreleased antibacterial macromolecules (DMAHDM, dimethylaminohexadecyl methacrylate), and released acid neutralizer amorphous calcium phosphate nanoparticles (NACP) have shown potential as individual and dual anticaries approaches. In this study, these agents were synthesized, and a prospective combination was incorporated into all the dental materials required to perform a composite restoration: dental primer, adhesive, and composite. We focused on combining different dental materials loaded with multiagents to improve the durability of the complex dental bonding interface. A combined effect of bacterial acid attack and fatigue on the bonding interface simulated the harsh oral environment. Human saliva-derived oral biofilm was grown on each sample prior to the cyclic loading. The oral biofilm viability during the fatigue performance was monitored by the live-dead assay. Damage of the samples that developed during the test was quantified from the fatigue life distributions. Results indicate that the resultant multiagent dental composite materials were able to reduce the acidic impact of the oral biofilm, thereby improving the strength and resistance to fatigue failure of the dentin-resin bonded interface. In summary, this study shows that dental restorative materials containing multiple therapeutic agents of different chemical characteristics can be beneficial toward improving resistance to mechanical and acidic challenges in oral

  19. Design and analysis of biomedical studies

    DEFF Research Database (Denmark)

    Hansen, Merete Kjær

    Biomedicine is a field that has great influence on the majority of mankind. The constant development has considerably changed our way of life during the last centuries. This has been achieved through the dedication of biomedical researchers along with the tremendous ressources that over time have...... been allocated this field. It is utterly important to utilize these ressources responsibly and efficiently by constantly striving to ensure high-quality biomedical studies. This involves the use of a sound statistical methodology regarding both the design and analysis of biomedical studies. The focus...... for biomedical studies are a recurring theme in this thesis. Data collected in some biomedical studies are positively skewed; hence methods relying on the normal distribution are not directly applicable. We investigated how data from one of these studies are suitably analyzed. We extracted 23 different summary...

  20. Experiments of Applying the Rare-Earth Modifying Agents in New Dental Materials Preparation

    Institute of Scientific and Technical Information of China (English)

    Chen Xiaohu; Wang Hua; Wang Qin; Li Xiaodi; Ma Rui

    2007-01-01

    Harmless rare-earth modifying agents were prepared by orthogonal experiments. A new resin material was synthesized with the qualities such as rigidity, rubbing abrasion, aging, luster and plasticity better than the dental resin materials in common used. It could be used as the substitutes for the applied resin teeth materials.

  1. Nanomaterials and nanofabrication for biomedical applications

    Science.gov (United States)

    Cheng, Chao-Min; Chia-Wen Wu, Kevin

    2013-08-01

    Traditional boundaries between materials science and engineering and life sciences are rapidly disintegrating as interdisciplinary research teams develop new materials-science-based tools for exploring fundamental issues in both medicine and biology. With recent technological advances in multiple research fields such as materials science, cell and molecular biology and micro-/nano-technology, much attention is shifting toward evaluating the functional advantages of nanomaterials and nanofabrication, at the cellular and molecular levels, for specific, biomedically relevant applications. The pursuit of this direction enhances the understanding of the mechanisms of, and therapeutic potentials for, some of the most lethal diseases, including cardiovascular diseases, organ fibrosis and cancers. This interdisciplinary approach has generated great interest among researchers working in a wide variety of communities including industry, universities and research laboratories. The purpose of this focus issue in Science and Technology of Advanced Materials is to bridge nanotechnology and biology with medicine, focusing more on the applications of nanomaterials and nanofabrication in biomedically relevant issues. This focus issue, we believe, will provide a more comprehensive understanding of (i) the preparation of nanomaterials and the underlying mechanisms of nanofabrication, and (ii) the linkage of nanomaterials and nanofabrication with biomedical applications. The multidisciplinary focus issue that we have attempted to organize is of interest to various research fields including biomaterials and tissue engineering, bioengineering, nanotechnology and nanomaterials, i.e. chemistry, physics and engineering. Nanomaterials and nanofabrication topics addressed in this focus issue include sensing and diagnosis (e.g. immunosensing and diagnostic devices for diseases), cellular and molecular biology (e.g. probing cellular behaviors and stem cell differentiation) and drug delivery

  2. Dental Training Films.

    Science.gov (United States)

    Veterans Administration Medical Center, Washington, DC.

    This dental training films catalog is organized into two sections. Section I is a category listing of the films by number and title, indexed according to generalized headings; categories are as follow: anatomy, articulator systems, complete dentures, dental assisting, dental laboratory technology, dental materials, dental office emergencies,…

  3. In situ reaction kinetic analysis of dental restorative materials

    Science.gov (United States)

    Younas, Basma; Samad Khan, Abdul; Muzaffar, Danish; Hussain, Ijaz; Chaudhry, Aqif Anwar; Rehman, Ihtesham Ur

    2013-12-01

    The objective of this study was to evaluate in situ structural and thermal changes of dental restorative materials at periodical time intervals. The commercial materials included zinc oxide eugenol (ZOE), zinc phosphate type I (ZnPO4), glass ionomer cement type II (GIC) and resin-based nano-omposite (Filtek Z350 XT). These materials were processed according to manufacturer's instructions. For the structural analysis Fourier transform infrared spectroscopy (FTIR) was used at high resolution. TGA was used to evaluate thermal weight-loss. The FTIR spectra were collected at periodic time intervals. FTIR spectra showed that with time passing all materials exhibited an increase in peak intensities and a new appearance of shoulders and shifting of peaks for example, ZnPO4 (P-O), ZOE (C═O, C═N, C-O-C), GIC (COO-, C-H, Si-OH), composites (C═O, C═C, C═N, C-N-H). The peaks were replaced by bands and these bands became broader with time interval. Composites showed a degree of conversion and new peaks corresponded to the cross-linking of polymer composites. TGA analysis showed that significant changes in weight loss of set materials were observed after 24 h, where ZOE showed continuous changes in thermal degradation. The spectral changes and thermal degradation with time interval elucidated in situ setting behaviour and understanding of their bonding compatibility with tooth structure and change in relation to time.

  4. Dental students' motivation and the context of learning

    DEFF Research Database (Denmark)

    Kristensen, Bettina Tjagvad; Netterstrom, Ingeborg; Kayser, Lars

    2009-01-01

    This qualitative study shows dental students' motives for choosing the dental education and how the motives influence their motivation at the first semester of study. Further the study demonstrates the relevance of the context of learning. This issue is of importance when planning a curriculum...... for the dental education. The material consists of interviews with eight dental students. The results show that dental students were focused on their future professional role, its practical dimensions and their future working conditions. Their motivation for choosing the dental education was found to influence...... their motivation for studying and their experience of the relevance of the first semester. The dental students who had co-education with the medical students at the first year of study missed a dental context and courses with clinically relevant contents. In conclusion, our data signify the importance...

  5. Microstructure and thermal diffusivity in hydroxyapatite, dense bone and metals for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Mendez, M.; Diaz G, J.A.I.; Calderon, A. [CICATA-IPN, Legaria 694, 11500 Mexico D.F. (Mexico)

    2006-07-01

    We report X-Ray diffraction and SEM analysis in hydroxyapatite obtained in powder form, as well as a SEM analysis in titanium, 316l stainless steel and dense bone in longitudinal and transversal cutting. Moreover, we realized a thermal diffusivity measurement in these materials in order to obtain the thermal compatibility between them. We use the photoacoustic technique in heat transmission configuration in order to obtain the thermal diffusivity values in the samples. Our results show a good thermal compatibility (74%) between hydroxyapatite and bone. Finally, it was obtained a one order of magnitude difference between the thermal diffusivity values of metallic samples and those corresponding values to bone and HA being this difference greater in titanium than in stainless steel, which is important to consider in some biomedical and dental applications. (Author)

  6. Dental pulp response to bacterial cell wall material.

    Science.gov (United States)

    Warfvinge, J; Dahlén, G; Bergenholtz, G

    1985-08-01

    Lipopolysaccharides (LPS) from Bacteroides oralis and Veillonella parvula and cell wall material from Lactobacillus casei were studied for their capacity to induce leukocyte migration in the dental pulp and in an implanted wound chamber. Three adult monkeys were challenged using lyophilized material sealed into buccal Class V cavities prepared in dentin. Pulp tissue responses were observed histologically eight and 72 hours after initiation of the experiment. Subjacent to cut dentinal tubules, bacterial materials induced polymorphonuclear leukocyte (PMN's) infiltration in the pulp tissue of the majority of test teeth examined. Responses were similar for the three bacterial test materials at both time periods. Topical applications of bovine serum albumin (BSA), used as a control, induced significantly less accumulation of PMN's. Assessments of induced exudate volumes and leukocyte densities in chambers implanted in rats showed comparable rankings with pulpal experiment between test (i.e., bacterial) and control (BSA) materials. Analysis of the data indicates that high-molecular-weight complexes of bacterial cell walls may adversely affect pulpal tissue across freshly exposed dentin.

  7. [Dental restoration materials in pediatric dentistry].

    Science.gov (United States)

    Davidson, C L

    1997-02-01

    Restorative materials in pediatric dentistry have to fulfill special requirements. They should be easy to handle and applicable in a not always dry mouth. They should potentially be adhesive in order to avoid too much mechanical preparation. They do not have to be extremely wear resistant as the dwell time of the restorations is relatively short. Glass-ionomer cements and in particular the resin modified types possess properties which make them almost ideal for the required purpose.

  8. Stretchable conducting materials with multi-scale hierarchical structures for biomedical applications

    Science.gov (United States)

    Kim, Hyun; Shim, Bong Sup

    2014-08-01

    Electrogenetic tissues in human body such as central and peripheral nerve systems, muscular and cardiomuscular systems are soft and stretchable materials. However, most of the artificial materials, interfacing with those conductive tissues, such as neural electrodes and cardiac pacemakers, have stiff mechanical properties. The rather contradictory properties between natural and artificial materials usually cause critical incompatibility problems in implanting bodymachine interfaces for wide ranges of biomedical devices. Thus, we developed a stretchable and electrically conductive material with complex hierarchical structures; multi-scale microstructures and nanostructural electrical pathways. For biomedical purposes, an implantable polycaprolactone (PCL) membrane was coated by molecularly controlled layer-bylayer (LBL) assembly of single-walled carbon nanotubes (SWNTs) or poly(3,4-ethylenedioxythiophene) (PEDOT). The soft PCL membrane with asymmetric micro- and nano-pores provides elastic properties, while conductive SWNT or PEDOT coating preserves stable electrical conductivity even in a fully stretched state. This electrical conductivity enhanced ionic cell transmission and cell-to-cell interactions as well as electrical cellular stimulation on the membrane. Our novel stretchable conducting materials will overcome long-lasting challenges for bioelectronic applications by significantly reducing mechanical property gaps between tissues and artificial materials and by providing 3D interconnected electro-active pathways which can be available even at a fully stretched state.

  9. Biomedical Optical Imaging Technologies Design and Applications

    CERN Document Server

    2013-01-01

    This book provides an introduction to design of biomedical optical imaging technologies and their applications. The main topics include: fluorescence imaging, confocal imaging, micro-endoscope, polarization imaging, hyperspectral imaging, OCT imaging, multimodal imaging and spectroscopic systems. Each chapter is written by the world leaders of the respective fields, and will cover: principles and limitations of optical imaging technology, system design and practical implementation for one or two specific applications, including design guidelines, system configuration, optical design, component requirements and selection, system optimization and design examples, recent advances and applications in biomedical researches and clinical imaging. This book serves as a reference for students and researchers in optics and biomedical engineering.

  10. Translational Bioinformatics and Clinical Research (Biomedical) Informatics.

    Science.gov (United States)

    Sirintrapun, S Joseph; Zehir, Ahmet; Syed, Aijazuddin; Gao, JianJiong; Schultz, Nikolaus; Cheng, Donavan T

    2016-03-01

    Translational bioinformatics and clinical research (biomedical) informatics are the primary domains related to informatics activities that support translational research. Translational bioinformatics focuses on computational techniques in genetics, molecular biology, and systems biology. Clinical research (biomedical) informatics involves the use of informatics in discovery and management of new knowledge relating to health and disease. This article details 3 projects that are hybrid applications of translational bioinformatics and clinical research (biomedical) informatics: The Cancer Genome Atlas, the cBioPortal for Cancer Genomics, and the Memorial Sloan Kettering Cancer Center clinical variants and results database, all designed to facilitate insights into cancer biology and clinical/therapeutic correlations.

  11. Dental anxiety and salivary cortisol levels before urgent dental care.

    Science.gov (United States)

    Kanegane, Kazue; Penha, Sibele S; Munhoz, Carolina D; Rocha, Rodney G

    2009-12-01

    Dental anxiety is still prevalent, despite advances in treatment, and affects the utilization of health care services. The purpose of this cross-sectional study was to determine if patients with different degrees of dental anxiety and pain undergoing emergency dental care have different stress reactions as measured by salivary cortisol. Seventy three patients completed the modified dental anxiety scale (MDAS), and described any previous dental traumatic experience. Their socio-demographic characteristics were also recorded. They also rated pain intensity on a 100 mm visual analogue scale (VAS). A saliva sample was collected before the procedure, and analyzed by enzyme immunoassay. Thirty patients were dentally anxious and forty one complained of pain. In this sample, dental anxiety was not related to gender, age, educational level and family income; however, a previous traumatic event was related to dental anxiety. There was no association between salivary cortisol concentrations and gender or dental anxiety. Patients with pain showed higher cortisol levels. When gathering patient information, the dentist should note patients' negative dental experiences in order to provide more effective, less traumatic treatment.

  12. Longevity of dental amalgam in comparison to composite materials

    Directory of Open Access Journals (Sweden)

    Windisch, Friederike

    2008-11-01

    fillings in posterior teeth is difficult. Apart from the difficulties in conducting a randomized, controlled long-term study comparing the longevity of direct fillings, the fact that composites and adhesives used in a study have often already been replaced by the next generation of the product at the time of study publication presents an additional problem. Not only the filling material, but also patient parameters and local, intraoral factors (e. g. localisation of the filling as well as the treating dentist have an impact on the longevity of dental fillings. In evaluating economic studies, one has to refer to the heterogeneity of data on longevity in the medical evaluation. The only effect parameter used in the studies is longevity, other aspects (e. g. long-term functionality are only referred to in discussions. Extensive counselling of patients regarding the selection of the appropriate filling material is important. Conclusions: Amalgam fillings show a longer longevity than composite fillings. Two out of six systematic reviews conclude that the expected survival time of composite fillings can be comparable to amalgam fillings. However, these conclusions are based on the results of short-term studies which usually overestimate the longevity of filling materials. From an economic standpoint, amalgam is the more economic filling material compared to direct composite fillings in posterior teeth when considering longevity as the only result parameter. Other aspects than longevity need to be considered in individually choosing the appropriate dental filling material. For future studies aiming to compare the longevity of amalgam and composite fillings, a sufficient sample size and study period, preferably in the setting of a private dental practice, should be aimed for. An evaluation of the cost-effectiveness of amalgam and composite fillings should take the functionality of teeth over a longer time period into account, as well as patients’ preferences. The rapid

  13. Telechelic Poly(2-oxazoline)s with a biocidal and a polymerizable terminal as collagenase inhibiting additive for long-term active antimicrobial dental materials

    Science.gov (United States)

    Fik, Christoph P.; Konieczny, Stefan; Pashley, David H.; Waschinski, Christian J.; Ladisch, Reinhild S.; Salz, Ulrich; Bock, Thorsten; Tiller, Joerg C.

    2015-01-01

    Although modern dental repair materials show excellent mechanical and adhesion properties, they still face two major problems: First, any microbes that remain alive below the composite fillings actively decompose dentin and thus, subsequently cause secondary caries. Second, even if those microbes are killed, the extracellular proteases such as MMP, remain active and can still degrade collagenousdental tissue. In order to address both problems, a poly(2-methyloxazoline) with a biocidal quaternary ammonium and a polymerizable methacrylate terminal was explored as additive for a commercial dental adhesive. It could be demonstrated that the adhesive rendered the adhesive contact-active antimicrobial against S. mutans at a concentration of only 2.5 wt% and even constant washing with water for 101 days did not diminish this effect. Increasing the amount of the additive to 5 wt% allowed killing S. mutans cells in the tubuli of bovinedentin upon application of the adhesive. Further, the additive fully inhibited bacterial collagenase at a concentration of 0.5 wt% and reduced human recombinant collagenase MMP-9 to 13% of its original activity at that concentration. Human MMPs naturally bound to dentin were inhibited by more than 96% in a medium containing 5 wt% of the additive. Moreover, no adverse effect on the enamel/dentine shear bond strength was detected in combination with a dental composite. PMID:25130877

  14. Bioceramic in dental implants: A review

    OpenAIRE

    Gaurav P Jayaswal; Dange, S. P.; Khalikar, A. N.

    2010-01-01

    Biomaterials are non-drug substance suitable for inclusion in system which augment or replace the function of bodily tissue or organ. Orthopedic and dental applications represent approximately 55% of the total biomaterials market. Changes in biologic responses and device design have been the direct result of advances in material science. Bioceramics fulfill a unique function as biomedical materials. Bioceramics are non-toxic and bioinert, bioactive or bioresorbable. Bioceramics continue to be...

  15. Degradation of a dental filling material after high caries challenge

    Directory of Open Access Journals (Sweden)

    Márcio Antonio Paraizo

    2004-12-01

    Full Text Available New types of copolymers using monomers which form inorganic polymers network (glass-like and organic networks have been developed, known as ormocers. The aim of this work was to study how a particular dental filling material is degraded when subjected to a caries challenge by using low pH solutions. The supernadants were studied by HPLC to detect the presence of molecules from the resin, while the changes of the material surface were evaluated by contact angle. An organic modified ceromer (ormocer called Definite® (Degussa was tested. Samples were built following manufacturer's instructions. After pH cycles, solutions were injected in a HPLC. The contact angle was obtained using a goniometer after and before the cycles. HPLC results showed material degradation, only detected in acid solutions. Bis-GMA and TEGDMA were detected in Definite® residues. Means and S.D. of contact angle were (p < 0,05: baseline: 85.16° ± 3.90° and after pH cycles: 69.77° ± 7.12°. The authors concluded that an ormocer filling material degraded on a caries simulated environment.

  16. [Dental records and responsibility

    NARCIS (Netherlands)

    Brands, W.G.

    2006-01-01

    Dental records are more than a small part of the bookkeeping. In most dental practises, keeping records is the task of a dental assistant. In civil court, the dentist is in most countries liable for the mistakes of his employees. In disciplinary court however there may be doubt whether the dentist i

  17. Bacterial cellulose-kaolin nanocomposites for application as biomedical wound healing materials

    Science.gov (United States)

    Wanna, Dwi; Alam, Catharina; Toivola, Diana M.; Alam, Parvez

    2013-12-01

    This short communication provides preliminary experimental details on the structure-property relationships of novel biomedical kaolin-bacterial cellulose nanocomposites. Bacterial cellulose is an effective binding agent for kaolin particles forming reticulated structures at kaolin-cellulose interfaces and entanglements when the cellulose fraction is sufficiently high. The mechanical performance of these materials hence improves with an increased fraction of bacterial cellulose, though this also causes the rate of blood clotting to decrease. These composites have combined potential as both short-term (kaolin) and long-term (bacterial cellulose) wound healing materials.

  18. Cognitive vulnerability and dental fear

    Directory of Open Access Journals (Sweden)

    Spencer A John

    2008-01-01

    Full Text Available Abstract Background The Cognitive Vulnerability Model proposes that perceptions of certain characteristics of a situation are critical determinants of fear. Although the model is applicable to all animal, natural environment and situational fears, it has not yet been applied specifically to dental fear. This study therefore aimed to examine the association between dental fear and perceptions of dental visits as uncontrollable, unpredictable and dangerous. Methods The study used a clustered, stratified national sample of Australians aged 15 years and over. All participants were asked in a telephone interview survey to indicate their level of dental fear. Participants who received an oral examination were subsequently provided with a self-complete questionnaire in which they rated their perceptions of uncontrollability, unpredictability and dangerousness associated with dental visiting. Results 3937 participants were recruited. Each of the three vulnerability-related perceptions was strongly associated with the prevalence of high dental fear. In a logistic regression analysis, uncontrollability and dangerousness perceptions were significantly associated with high dental fear after controlling for age and sex. However, unpredictability perceptions did not have a statistically significant independent association with dental fear after controlling for all other variables. Conclusion Results are mostly consistent with the Cognitive Vulnerability Model of the etiology of fear, with perceptions of uncontrollability, unpredictability and dangerousness each showing a strong bivariate relationship with high dental fear prevalence. However, more extensive measures of vulnerability perceptions would be valuable in future investigations.

  19. Effect of disinfection of irreversible hydrocolloid impression materials with 1% sodium hypochlorite on surface roughness and dimensional accuracy of dental stone casts

    Directory of Open Access Journals (Sweden)

    Andressa Rodrigues Dorner

    2014-01-01

    Full Text Available Aim: The aim of this study was to evaluate the effect of disinfection of commercially available irreversible hydrocolloid impression materials with 1% sodium hypochlorite on the surface roughness and dimensional accuracy of dies produced using type IV dental stone. Materials and Methods: Four different brands of irreversible hydrocolloid impression materials were used as follows: Jeltrate Plus without disinfection (GJ, Jeltrate Plus with disinfection (GJD, Hydrogum without disinfection (GH, Hidrogun with disinfection (GHD, Hidrogum 5 Days without disinfection (GH5, Hidrogum 5 Days with disinfection (GH5D, Cavex without disinfection (GC, and Cavex with disinfection (GCD. A total of 80 dies were poured using type IV dental stone and their mean surface roughness was evaluated using rugosimeter (Mitutoyo SJ-400. To conduct the dimensional alteration analysis, type IV dental stone casts were obtained from a matrix made of chemically-activated resin. They were analyzed in a coordinate-measuring machine (Brown and Sharpe. Statistics Analysis: Numerical data were analyzed using analysis of variance (ANOVA with Tukey′s post hoc test at 5% confi dence interval. Results: Hidrogun 5 Days and Cavex showed the least surface roughness value even after 5 days. There were no significant differences in the dimensional alteration of Jeltrate (GJ and GJD and Hidrogum (GH and GHD in relation to the "new brands" Hidrogum 5 (GH5 and GH5D and Cavex (GC and GCD, even after 5 days of storage. Conclusion: Considering the results obtained, it can be concluded that there was a roughness increase in the die stones poured from irreversible hydrocolloids disinfected with sodium hypochlorite.

  20. Evaluation of the effect of tooth and dental restoration material on electron dose distribution and production of photon contamination in electron beam radiotherapy.

    Science.gov (United States)

    Bahreyni Toossi, Mohammad Taghi; Ghorbani, Mahdi; Akbari, Fatemeh; Mehrpouyan, Mohammad; Sobhkhiz Sabet, Leila

    2016-03-01

    The aim of this study is to evaluate the effect of tooth and dental restoration materials on electron dose distribution and photon contamination production in electron beams of a medical linac. This evaluation was performed on 8, 12 and 14 MeV electron beams of a Siemens Primus linac. MCNPX Monte Carlo code was utilized and a 10 × 10 cm(2) applicator was simulated in the cases of tooth and combinations of tooth and Ceramco C3 ceramic veneer, tooth and Eclipse alloy and tooth and amalgam restoration materials in a soft tissue phantom. The relative electron and photon contamination doses were calculated for these materials. The presence of tooth and dental restoration material changed the electron dose distribution and photon contamination in phantom, depending on the type of the restoration material and electron beam's energy. The maximum relative electron dose was 1.07 in the presence of tooth including amalgam for 14 MeV electron beam. When 100.00 cGy was prescribed for the reference point, the maximum absolute electron dose was 105.10 cGy in the presence of amalgam for 12 MeV electron beam and the maximum absolute photon contamination dose was 376.67 μGy for tooth in 14 MeV electron beam. The change in electron dose distribution should be considered in treatment planning, when teeth are irradiated in electron beam radiotherapy. If treatment planning can be performed in such a way that the teeth are excluded from primary irradiation, the potential errors in dose delivery to the tumour and normal tissues can be avoided.

  1. Dental Anxiety among Medical and Paramedical Undergraduate Students of Malaysia

    Science.gov (United States)

    Parkar, Sujal

    2017-01-01

    Aim. To assess the dental anxiety level among dental, medical, and pharmacy students of MAHSA University, Malaysia. Materials and Methods. A cross-sectional questionnaire study was conducted among 1500 undergraduate students of MAHSA University. The Modified Dental Anxiety Scale (MDAS) was used to measure dental anxiety among the study population. The responses were assessed by 5-point likert scale ranging from 1 to 5. The level of anxiety was categorized into lowly anxious (5–11), moderately anxious (12–18), and severely anxious ≥19. Out of 1500 students enrolled, 1024 students (342 males and 682 females) completed and returned the questionnaire having response rate of 68.26%. Results. There was a statistically significant difference (P < 0.001) when the mean dental anxiety scores were compared among the three faculties and dental students had lowest mean score (11.95 ± 4.21). The fifth year (senior) dental students scored significantly (P = 0.02) lower mean anxiety score as compared to the first dental students (junior). The students were anxious mostly about tooth drilling and local anesthetic injection. Conclusions. Dental students have a significantly low level of dental anxiety as compared with medical and pharmacy students. Incorporation of dental health education in preuniversity and other nondental university curriculums may reduce dental anxiety among the students.

  2. A Program on Biochemical and Biomedical Engineering.

    Science.gov (United States)

    San, Ka-Yiu; McIntire, Larry V.

    1989-01-01

    Presents an introduction to the Biochemical and Biomedical Engineering program at Rice University. Describes the development of the academic and enhancement programs, including organizational structure and research project titles. (YP)

  3. Biomedical applications of polymers

    CERN Document Server

    Gebelein, C G

    1991-01-01

    The biomedical applications of polymers span an extremely wide spectrum of uses, including artificial organs, skin and soft tissue replacements, orthopaedic applications, dental applications, and controlled release of medications. No single, short review can possibly cover all these items in detail, and dozens of books andhundreds of reviews exist on biomedical polymers. Only a few relatively recent examples will be cited here;additional reviews are listed under most of the major topics in this book. We will consider each of the majorclassifications of biomedical polymers to some extent, inclu

  4. Biomedical image understanding methods and applications

    CERN Document Server

    Lim, Joo-Hwee; Xiong, Wei

    2015-01-01

    A comprehensive guide to understanding and interpreting digital images in medical and functional applications Biomedical Image Understanding focuses on image understanding and semantic interpretation, with clear introductions to related concepts, in-depth theoretical analysis, and detailed descriptions of important biomedical applications. It covers image processing, image filtering, enhancement, de-noising, restoration, and reconstruction; image segmentation and feature extraction; registration; clustering, pattern classification, and data fusion. With contributions from ex

  5. Biomedical engineering fundamentals

    CERN Document Server

    Bronzino, Joseph D

    2014-01-01

    Known as the bible of biomedical engineering, The Biomedical Engineering Handbook, Fourth Edition, sets the standard against which all other references of this nature are measured. As such, it has served as a major resource for both skilled professionals and novices to biomedical engineering.Biomedical Engineering Fundamentals, the first volume of the handbook, presents material from respected scientists with diverse backgrounds in physiological systems, biomechanics, biomaterials, bioelectric phenomena, and neuroengineering. More than three dozen specific topics are examined, including cardia

  6. Photoreconfigurable polymers for biomedical applications: chemistry and macromolecular engineering.

    Science.gov (United States)

    Zhu, Congcong; Ninh, Chi; Bettinger, Christopher J

    2014-10-13

    Stimuli-responsive polymers play an important role in many biomedical technologies. Light responsive polymers are particularly desirable because the parameters of irradiated light and diverse photoactive chemistries produce a large number of combinations between functional materials and associated stimuli. This Review summarizes recent advances in utilizing photoactive chemistries in macromolecules for prospective use in biomedical applications. Special focus is granted to selection criterion when choosing photofunctional groups. Synthetic strategies to incorporate these functionalities into polymers and networks with different topologies are also highlighted herein. Prospective applications of these materials are discussed including programmable matrices for controlled release, dynamic scaffolds for tissue engineering, and functional coatings for medical devices. The article concludes by summarizing the state of the art in photoresponsive polymers for biomedical applications including current challenges and future opportunities.

  7. Porous silicon nanoparticles for nanomedicine: preparation and biomedical applications.

    Science.gov (United States)

    Santos, Hélder A; Mäkilä, Ermei; Airaksinen, Anu J; Bimbo, Luis M; Hirvonen, Jouni

    2014-04-01

    The research on porous silicon (PSi) materials for biomedical applications has expanded greatly since the early studies of Leigh Canham more than 25 years ago. Currently, PSi nanoparticles are receiving growing attention from the scientific biomedical community. These nanostructured materials have emerged as promising multifunctional and versatile platforms for nanomedicine in drug delivery, diagnostics and therapy. The outstanding properties of PSi, including excellent in vivo biocompatibility and biodegradability, have led to many applications of PSi for delivery of therapeutic agents. In this review, we highlight current advances and recent efforts on PSi nanoparticles regarding the production properties, efficient drug delivery, multidrug delivery, permeation across biological barriers, biosafety and in vivo tracking for biomedical applications. The constant boost on successful preclinical in vivo data reported so far makes this the 'golden age' for PSi, which is expected to finally be translated into the clinic in the near future.

  8. Pharmaceutical and biomedical applications of quantum dots.

    Science.gov (United States)

    Bajwa, Neha; Mehra, Neelesh K; Jain, Keerti; Jain, Narendra K

    2016-05-01

    Quantum dots (QDs) have captured the fascination and attention of scientists due to their simultaneous targeting and imaging potential in drug delivery, in pharmaceutical and biomedical applications. In the present study, we have exhaustively reviewed various aspects of QDs, highlighting their pharmaceutical and biomedical applications, pharmacology, interactions, and toxicological manifestations. The eventual use of QDs is to dramatically improve clinical diagnostic tests for early detection of cancer. In recent years, QDs were introduced to cell biology as an alternative fluorescent probe.

  9. Biomedical photonics handbook therapeutics and advanced biophotonics

    CERN Document Server

    Vo-Dinh, Tuan

    2014-01-01

    Shaped by Quantum Theory, Technology, and the Genomics RevolutionThe integration of photonics, electronics, biomaterials, and nanotechnology holds great promise for the future of medicine. This topic has recently experienced an explosive growth due to the noninvasive or minimally invasive nature and the cost-effectiveness of photonic modalities in medical diagnostics and therapy. The second edition of the Biomedical Photonics Handbook presents recent fundamental developments as well as important applications of biomedical photonics of interest to scientists, engineers, manufacturers, teachers,

  10. METHACRYLATE AND ACRYLATE ALLERGY IN DENTAL STUDENTS.

    Directory of Open Access Journals (Sweden)

    Maya Lyapina

    2013-09-01

    Full Text Available A multitude of acrylic monomers is used in dentistry, and when dental personnel, patients or students of dental medicine become sensitized, it is of great importance to identify the dental ;acrylic preparations to which the sensitized individual can be exposed. Numerous studies confirm high incidence of sensitization to (meth acrylates in dentatal professionals, as well as in patients undergoing dental treatment and exposed to resin-based materials. Quite a few studies are available aiming to evaluate the incidence of sensitization in students of dental medicineThe purpose of the study is to evaluate the incidence of contact sensitization to some (meth acrylates in students of dental medicine at the time of their education, in dental professionals (dentists, nurses and attendants and in patients, the manifestation of co-reactivity.A total of 139 participants were included in the study, divided into four groups: occupationally exposed to (methacrylates and acrylic monomers dental professionals, 3-4 year-of-education students of dental medicine, 6th year–of-education students of dental medicine and patients with suspected or established sensitization to acrylates, without occupational exposure. All of them were patch-tested with methyl methacrylate (MMA, triethyleneglycol dimethacrylate (TREGDMA, ethyleneglycol dimethacrylate (EGDMA, 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy phenyl]propane (bis-GMA, 2-hydroxyethyl methacrylate (2-HEMA, and tetrahidrofurfuril metacrylate. The overall sensitization rates to methacrylates in the studied population are comparative high – from 25.9% for MMA to 31.7% for TREGDMA. Significantly higher incidence of sensitization in the group of 3-4 course students compared to the one in the group of dental professionals for MMA and TREGDMA was observed. Highest was the incidence of sensitization to ethyleneglycol dimethacrylate, BIS-GMA, 2-HEMA and tetrahydrofurfuryl methacrylate in the group of patients, with

  11. Preparation and characterization of new dental porcelains, using K-feldspar and quartz raw materials. Effect of B2O3 additions on sintering and mechanical properties.

    Science.gov (United States)

    Harabi, Abdelhamid; Guerfa, Fatiha; Harabi, Esma; Benhassine, Mohamed-Tayeb; Foughali, Lazhar; Zaiou, Soumia

    2016-08-01

    The aim of this work was to determine the effect of temperature and boric oxide (B2O3) addition on sintering and mechanical properties of a newly developed dental porcelain (DP) prepared from local Algerian raw materials. Based on a preliminary work, the new selected composition was 75wt.% feldspar, 20wt.% quartz and 5wt.% kaolin. It was prepared by sintering the mixture at different temperatures (1100-1250°C). The optimum sintering conditions gave a relatively higher density (2.47g/cm(3)) and excellent mechanical properties. The three point flexural strength (3PFS) and Martens micro-hardness of dental porcelains were 149MPa and 2600MPa, respectively. This obtained 3PFS value is more than four times greater than that of hydroxyapatite (HA) value (about 37MPa) sintered under the same conditions. However, the sintering temperature was lowered by about 25 and 50°C for 3 and 5wt.% B2O3 additions, respectively. But, it did not improve furthermore the samples density and their mechanical properties. It has also been found that B2O3 additions provoke a glass matrix composition variation which delays the leucite formation during sintering.

  12. Dentistry and Dental Hygiene Handbook.

    Science.gov (United States)

    New York State Education Dept., Albany. Office of the Professions.

    The handbook contains laws, rules, and regulations of the New York State Education Department that govern dentistry and dental hygiene practice in the state. It describes licensure requirements and includes complete application forms and instructions for obtaining license and first registration as a dentist and dental hygienist. Applicants are…

  13. Prevalence of Dental Fear and Anxiety amongst Patients in Selected Dental Clinics in Ghana

    Science.gov (United States)

    Ofori, Marian A.; Adu-Ababio, F.; Nyako, E. A.; Ndanu, Tom A.

    2009-01-01

    Objective: To find out the prevalence of dental anxiety and fear amongst patients in various selected dental clinics in Accra, Ghana. Study design: Dental patients (n = 279) who had either been exposed to dental treatments or had no prior dental exposure, attending four selected dental clinics in Accra were randomly sampled. They were interviewed…

  14. Competition and dental services.

    Science.gov (United States)

    Grytten, J; Sørensen, R

    2000-07-01

    Dental services for adults are different from all other Norwegian health services in that they are provided by private producers (dentists) who have full freedom to establish a practice. They have had this freedom since the end of World War II. A further liberalization of the market for dental services occurred in November 1995, when the so-called normal tariff was repealed. The system changed from a fixed fee system to a deregulated fee system. In principle, the market for dental services for adults operates as a free competitive market, in which dentists must compete for a market share. The aim of this study was to study the short-term effects of competition. A comprehensive set of data on fees, practice characteristics, treatment profiles and factors that dentists take into account when determining fees was analysed. The main finding was that competition has a weak effect. No support was found for the theory that the level of fees is the result of monopolistic competition or monopoly. The results also provided some evidence against the inducement hypothesis. At this stage, it is interesting to notice that dentists do not seem to exploit the power they have to control the market. One explanation, which is consistent with the more recent literature, is that physicians' behaviour to a large extent is influenced by professional norms and caring concerns about their patients. Financial incentives are important, but these incentives are constrained by norms other than self-interest. The interpretation of the results should also take into account that the deregulation has operated for a short time and that dentists and patients may not yet have adjusted to changes in the characteristics of the market.

  15. Biomedical engineering and society: policy and ethics.

    Science.gov (United States)

    Flexman, J A; Lazareck, L

    2007-01-01

    Biomedical engineering impacts health care and contributes to fundamental knowledge in medicine and biology. Policy, such as through regulation and research funding, has the potential to dramatically affect biomedical engineering research and commercialization. New developments, in turn, may affect society in new ways. The intersection of biomedical engineering and society and related policy issues must be discussed between scientists and engineers, policy-makers and the public. As a student, there are many ways to become engaged in the issues surrounding science and technology policy. At the University of Washington in Seattle, the Forum on Science Ethics and Policy (FOSEP, www.fosep.org) was started by graduate students and post-doctoral fellows interested in improving the dialogue between scientists, policymakers and the public and has received support from upper-level administration. This is just one example of how students can start thinking about science policy and ethics early in their careers.

  16. Engineering a material for biomedical applications with electric field assisted processing

    Science.gov (United States)

    Ahmad, Z.; Nangrejo, M.; Edirisinghe, M.; Stride, E.; Colombo, P.; Zhang, H. B.

    2009-10-01

    In this work, using multiple co-flows we demonstrate in-situ encapsulation of nano-particles, liquids and/or gases in different structural morphologies, which can also be deposited in a designated pattern by a direct write method and surface modification can be controlled to release encapsulated material. The range of possibilities offered by exposing a material solution to an applied electric field can result in a plethora of structures which can accommodate a whole host of biomedical applications from microfluidic devices (microchannels, loaded with various materials), printed 3D structures and patterns, lab-on-a-chip devices to encapsulated materials (capsules, tubes, fibres, dense multi-layered fibrous networks) for drug delivery and tissue engineering. The structures obtained in this way can vary in size from micrometer to the nanometer range and the processing is viable for all states of matter. The work shown demonstrates some novel structures and methodologies for processing a biomaterial.

  17. Dentistry and Dental Hygiene Handbook.

    Science.gov (United States)

    New York State Education Dept., Albany. Office of the Professions.

    A reference guide to laws, rules, and regulations that govern dentistry and dental hygiene practice in New York State is presented. In addition to identifying licensing requirements/procedures for dentists and dental hygienists, general provisions of Title VIII of the Education Law are covered, along with state management, professional misconduct,…

  18. Social support and dental utilization among children of Latina immigrants.

    Science.gov (United States)

    Nahouraii, Helen; Wasserman, Melanie; Bender, Deborah E; Rozier, R Gary

    2008-05-01

    Latino children use fewer professional dental services and experience more dental decay than non-Hispanic White and non-Hispanic Black children. This study tested the association between four types of social support (information, influence, material aid, emotional aid) and dental use among children of Latina immigrants in North Carolina. Latina mothers age 15-44 years (N=174) were sampled from four counties using a multistage church-based sampling design. Each mother reported dental care use for her oldest child younger than 11 years of age. Instrumental aid (information) alone was not associated with dental care use, but receiving any of the other types of social support was associated with dental care use at the bivariate level (pdental-related social support could help Latina immigrant mothers overcome barriers to dental care for their children.

  19. Holography And Holometry Applications In Dental Research

    Science.gov (United States)

    Willenborg, George C.

    1987-06-01

    The earliest reference to holographic applications appeared in the dental literature in 1972 when Wictorin, Bjelkhagen and Abramson described a method to study elastic deformation of defective gold solder joints in simulated fixed bridges. Their paper, published in the Swedish dental literature, offered a concise presentation of the interferometry technique which led to the development of other research applications of holographic interferometry(holometry) in dentistry. In this presentation, the development and application of the interferometry technique in the dental field will be discussed. Various interesting and potentially useful applications of holography have appeared in the dental literature over the past decade. Some of these, which will be discussed, include the use of holograms as a storage medium for dental study models, multiplexing of computer(CT) scan sections to form white light viewable holograms and the potential application of holographic training aids in the teaching of the basic courses of dental anatomy and restorative dentistry. In addition, some unique related applications will be mentioned including a laser reflection method for accurate non-contact measurement of tooth mobility/movement and a technique for contour mapping of occlusal surfaces to measure wear of restorative materials.

  20. Dental health and dental treatment needs in patients with thalassemia major

    Directory of Open Access Journals (Sweden)

    Marieh Honarmand

    2010-09-01

    Full Text Available Background: Patients with thalassemia major needs more dental care due to their medically compromised condition. The aim of this study was to evaluate the dental health and dental treatment needs of these patients at Zahedan university school of Dentistry in 2009.Materials and Method: In this descriptive-analytical study, 75 patients with thalassemia major were selected in which 42 boys and 33 girls with mean age of 10.79±6.2 referred to community dentistry center as the case group and 75 patients' relatives referred to Zahedan school of Dentistry as the control group. Two groups matched for age and sex. The studied variables were patient's educational level and their parents, dental caries and treatment needs. Statistical analysis was carried out by chi-squared test and t-test.Results: Thalassemic patient had increased average dental caries and missing (d=2.24, m=0.13, D=2.49, M=0.52 than the control group (d=2.13, m=0.05, D=0.97, M=0.35. Pulp therapy was the most needed treatment in patient group and in the other group filling dental caries was needed more. Conclusion: According to the high incidence of dental caries in patient with thalassemic major, effective preventive measures, health education and dental treatment are needed for this group.

  1. Ensuring the global availability of high-quality dental restorative materials.

    Science.gov (United States)

    Ferracane, J; Fisher, J; Eiselé, J L; Fox, C H

    2013-11-01

    The Minamata Convention, a global legally binding instrument (treaty) on mercury, has been the catalyst for the emerging agenda on global dental materials research. If the current and future challenges of oral health maintenance and healing on a global scale are to be met, a logical and effective research agenda for the discovery and introduction of new, environmentally sustainable, dental materials must be developed through a coordinated effort involving materials scientists, dental clinicians, representatives of industry, members of regional and national regulatory bodies, and advocacy from research organizations. For universal impact, this agenda should be created with awareness of several important ongoing initiatives, such as the WHO non-communicable diseases action plan, the UN sustainable development agenda, and the IADR Global Oral Health In Inequalities Research Agenda (GOHIRA). A significant contributor to this cause is the FDI and its membership, who, through their Vision 2020 initiative, acknowledge their role and responsibility in globally preventing and managing dental disease and providing leadership to the profession in terms of information dissemination and affecting change. Dental researchers also have an obligation to advocate for appropriate funding to match the identified research needs, thus enhancing the possibility that key decision-makers will provide the needed support to achieve the research agenda agreed upon by this diverse group of stakeholders.

  2. The Swedish national dental insurance and dental health care policy

    DEFF Research Database (Denmark)

    Moore, Rod

    1981-01-01

    Sweden initiated a dental health care insurance in 1973. The health insurance is outlined, current problems and political issues are described. The benefits and limitations are described.......Sweden initiated a dental health care insurance in 1973. The health insurance is outlined, current problems and political issues are described. The benefits and limitations are described....

  3. Unilateral and bilateral dental transpositions in the maxilla

    DEFF Research Database (Denmark)

    Danielsen, Jakob Christian; Karimian, K; Ciarlantini, R;

    2015-01-01

    AIM: This was to elucidate dental and skeletal findings in individuals with unilateral and bilateral maxillary dental transpositions. MATERIAL AND METHODS: The sample comprised of radiographic materials from 63 individuals with maxillary dental transpositions from the Departments of Odontology...... and lateral incisor (Type 2). The dentitions were analysed regarding agenesis and dental morphological anomalies on panoramic radiographs, and craniofacial aspects were cephalometrically analysed on profile images The results were statistically evaluated. RESULTS: All groups demonstrated increased occurrences...... retrognathia (more pronounced in Type 1B). Type 2 showed a significant posterior inclination of the maxilla. CONCLUSION: Transpositions of maxillary canines involve dental and skeletal deviations. Dental deviations were predominantly taurodontic root morphology and agenesis. Regarding skeletal deviations...

  4. Tetracycline Loaded Collagen/Hydroxyapatite Composite Materials for Biomedical Applications

    OpenAIRE

    2015-01-01

    The paper describes the preparation, characterisation, and testing of tetracycline loaded collagen-carboxymethylcellulose/hydroxyapatite ternary composite materials. The synthesis of this drug delivery system consists in two steps: the first step is the mineralization of collagen-carboxymethylcellulose gel while the second step corresponds to the loading of the ternary composite material with tetracycline. The obtained DDS is characterised by physicochemical, morphological, and release behavi...

  5. Mandatory Clinical Practice for Dental and Dental Hygiene Faculty.

    Science.gov (United States)

    Cameron, Cheryl A.; And Others

    1982-01-01

    Dental and dental hygiene faculty should maintain their clinical skills through regular practice, to improve their ability to relate to students through instruction, provide an additional source of income, and improve their image in the community. Institutional policies fostering and regulating faculty practice plans are suggested. (Author/MSE)

  6. Release and toxicity of dental resin composite.

    Science.gov (United States)

    Gupta, Saurabh K; Saxena, Payal; Pant, Vandana A; Pant, Aditya B

    2012-09-01

    Dental resin composite that are tooth-colored materials have been considered as possible substitutes to mercury-containing silver amalgam filling. Despite the fact that dental resin composites have improved their physico-chemical properties, the concern for its intrinsic toxicity remains high. Some components of restorative composite resins are released in the oral environment initially during polymerization reaction and later due to degradation of the material. In vitro and in vivo studies have clearly identified that these components of restorative composite resins are toxic. But there is a large gap between the results published by research laboratories and clinical reports. The objective of this manuscript was to review the literature on release phenomenon as well as in vitro and in vivo toxicity of dental resin composite. Interpretation made from the recent data was also outlined.

  7. Quantification of Staphylococcus aureus adhesion forces on various dental restorative materials using atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Merghni, Abderrahmen, E-mail: abderrahmen_merghni@yahoo.fr [Laboratoire des Maladies Transmissibles et Substances biologiquement actives (LR99ES27) Faculté de Pharmacie de Monastir, Université de Monastir (Tunisia); Kammoun, Dorra [Laboratoire de Biomatériaux et Biotechnologie, Faculté de Médecine Dentaire, Monastir (Tunisia); Hentati, Hajer [Laboratoire de Recherche en Santé Orale et Réhabilitation Bucco-Faciale (LR12ES11), Faculté de Médecine Dentaire de Monastir, Université de Monastir (Tunisia); Janel, Sébastien [BioImaging Center Lille-FR3642, Lille (France); Popoff, Michka [Cellular Microbiology and Physics of Infection-CNRS UMR8204, INSERM U1019, Institut Pasteur de Lille, Lille University (France); Lafont, Frank [BioImaging Center Lille-FR3642, Lille (France); Cellular Microbiology and Physics of Infection-CNRS UMR8204, INSERM U1019, Institut Pasteur de Lille, Lille University (France); Aouni, Mahjoub [Laboratoire des Maladies Transmissibles et Substances biologiquement actives (LR99ES27) Faculté de Pharmacie de Monastir, Université de Monastir (Tunisia); Mastouri, Maha [Laboratoire des Maladies Transmissibles et Substances biologiquement actives (LR99ES27) Faculté de Pharmacie de Monastir, Université de Monastir (Tunisia); Laboratoire de Microbiologie, CHU Fattouma Bourguiba de Monastir (Tunisia)

    2016-08-30

    Highlights: • 4 dental restorative materials were characterized for roughness, angle contact water and surface free energy. • AFM adhesion forces of S. aureus to tested materials were achieved in presence and absence of salivary conditioning film. • S. aureus initial adhesion is dependent on the surface free energy and roughness. - Abstract: In the oral cavity dental restorative biomaterials can act as a reservoir for infection with opportunistic Staphylococcus aureus pathogen, which can lead to the occurrence of secondary caries and treatment failures. Our aim was to evaluate the adhesion forces by S. aureus on four dental restorative biomaterials and to correlate this finding to differences in specific surface characteristics. Additionally, the influence of salivary conditioning films in exerted adhesion forces was investigated. The substrate hydrophobicity was measured by goniometer and the surface free energy was calculated using the equilibrium advancing contact angle values of water, formamide, and diiodomethane on the tested surfaces. The surface roughness was determined using atomic force microscope (AFM). Additionally, cell force spectroscopy was achieved to quantify the forces that drive cell-substrate interactions. S. aureus bacterium exerted a considerable adhesion forces on various dental restorative materials, which decreased in the presence of saliva conditioning film. The influence of the surface roughness and free energy in initial adhesion appears to be more important than the effect of hydrophobicity, either in presence or absence of saliva coating. Hence, control of surface properties of dental restorative biomaterials is of crucial importance in preventing the attachment and subsequent the biofilm formation.

  8. A new method for training of ear framework creation by silicon dental impression material.

    Science.gov (United States)

    Thadani, Sandeep M; Ladani, Parit S

    2012-01-01

    This article presents the novel method of training of creating cartilage framework for total ear reconstruction in microtia. Replica of costal cartilage harvested for real surgery was simulated by silicon dental impression material. Carving of framework was done with wood carving instruments. Silicon dental impression material gives the consistency and texture almost comparable to real costal cartilage. Sequential steps similar to actual surgery were simulated to create the three-dimensional framework.By using this novel technique, novice surgeons can practice creating ear framework and improvise their results in the actual surgery.

  9. Legal analysis of information displayed on dental material packages: An exploratory research

    Directory of Open Access Journals (Sweden)

    Bhumika Rathore

    2016-01-01

    Full Text Available Introduction: Some of the dental materials possess occupational hazards, preprocedural errors, and patient allergies as suggested by evidence. With due consideration to safety of the patients and dental professionals, it is essential that the trade of these materials is in conformity with the law. Aim: To perform the legal analysis of the information displayed on the packaging of dental materials. Materials and Methods: The Bureau of Indian Standards sets guidelines for packaging and marketing of dental products in India. An exploratory cross-sectional study was performed using various search engines and websites to access the laws and regulations existing pertaining to dental materials packaging. Based on the data obtained, a unique packaging standardization checklist was developed. Dental laboratory and impression plasters, alginates, and endodontic instruments were surveyed for all the available brands. This study considered 16 brands of plasters and alginates and 42 brands of endodontic instruments for legal analysis. Legal analysis was performed using the direct observation checklist. Descriptive statistics were obtained using SPSS version 19. Results: The guidelines set by the Bureau of Indian Standards do exist but are not updated and stand as oblivious guards for marketing standards. Overall compliance to the guidelines was reported to be 18.5% by brands of alginates, 4.1% by plaster of Paris, and 11.11% by endodontic instruments. Wave One™ File reported maximum adherence with the guidelines as 66.7%. Conclusion: This study found lower rate of adherence to the guidelines, thus indicating insufficient information being disclosed to the consumers.

  10. Enzymes, Dentinogenesis and Dental Caries: a Literature Review

    OpenAIRE

    2014-01-01

    ABSTRACT Objectives Search in PubMed with keywords “enzymes, dentinogenesis, and dental caries” revealed only 4 items, but when combined with “enzymes, osteogenesis, and osteoporosis” as high as 404 items resulted. Dental caries was associated with an order of magnitude fewer studies than the chronic bone disease, osteoporosis. This observation motivated this review. Material and Methods A comprehensive review of the available literature on role of enzymes in dentinogenesis and dental caries ...

  11. A survey on the use of techniques, materials in dental implantology practice

    Directory of Open Access Journals (Sweden)

    R Chowdhary

    2012-01-01

    Full Text Available Purpose: To present results of a survey on the status of an implantology amongst implant-practicing dentist across the world in 2009. Materials and Methods: A questionnaire was sent to the members of EAO (European Association of Osseointegration, ICOI (International Congress of Osseointegrated Implants, ISOI (Indian Society of Oral Implantologists, Asian Academy of Osseointegration (AAO, Deutsche Gasellschaft Fur Orale Implantologie (DGOI, Philippines Implant Organization, Korean Society of Oral Implantologist, Japanese Association of OralIimplantologists, Chinese Dental Association, Pakistan Dental Association, asking for the personal (anonymous background data and their implantology concepts. Specific questions dealt with level of recognition of implants, use of implants, superstructures, techniques followed, and materials used. Results: A total of 1500 (63.6% of the 2358 questionnaires were answered. Dental implants were the most preferred treatment modality for restoring the missing teeth. Threaded implants were the most preferred. Cement retained implant prosthesis was the most preferred restoration procedure. Dentists believe that the general dentist should practice dental implant treatment modality, preferably teamwork. Immediate loading was the much-accepted concept among the dentists of the developed nations. Conclusion: Dental implants were much accepted treatment modality for the replacement of missing teeth. Most the dentists follow the well documented technique and proven materials, which have been documented in the literature, an evidenced based practice, thus, delivering the best to their patients. Dentists from the developing nations agreed to have standardization in implants.

  12. Determination of setting expansion of dental materials using fibre optical sensing

    Science.gov (United States)

    Milczewski, M. S.; da Silva, J. C. C.; Abe, I.; Carvalho, L.; Nogueira, R. N.; Paterno, A. S.; Kalinowski, H. J.; Pinto, J. L.

    2006-05-01

    The use of fibre Bragg grating sensors to study dental materials like resin-based composite and gypsum products is reported. Two commercially available composite resins and three types of gypsum products were tested in order to determine polymerization contraction and setting expansion. Temperature and strain evolution during the hardening phase of the material were also obtained. The presented technique can be a good tool for dentists in order to better manipulate a material and predict how it will behave in vivo.

  13. A Study of Hybrid Composite Hydroxyapatite (HA-Geopolymers as a Material for Biomedical Application

    Directory of Open Access Journals (Sweden)

    Saleha

    2017-01-01

    Full Text Available The main purpose of this research is to study the physical properties and microstructure characters of hybrid composites HA-geopolymers as a material for biomedical application. Hybrid composite HA–geopolymers were produced through alkaline activation method of metakaolin as a matrix and HA as the filler. HA was synthesized from eggshell particles by using a precipitation method. The addition of HA in metakaolin paste was varied from 0.5%, 1.0%, 1.5%, and 2.0% relative the weight of metakaolin. FTIR was used to examine the absorption bands the composites. X-ray diffraction (XRD was used to study the crystal structure of the starting and the resulting materials. Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS was used to investigate the surface morphology of the composites. The thermal properties of the samples was examined by means of Differential Scanning Calorimetry (DSC. Capacitance measurement was conducted to investigate the bioactive properties of HA. The study results suggest that hybrid composite HA-geopolymers has a potential to be applied as a biomedical such as biosensor material.

  14. Innovation of dental education system for researcher, dentist, dental hygienist and dental technician in Hiroshima University

    OpenAIRE

    Kurihara, Hidemi

    2006-01-01

    Hiroshima University Faculty of Dentistry's goal is to become the worldwide research and education center in Dentistry. It seems to constitute the dental education by two missions: core and characteristic. Hiroshima University Faculty of Dentistry has clarified their characteristic mission and improved dental education system to reinforce the innovative part of the education. We started two programs to cultivate researchers/educators who will be a world-wide leader of dental research and educ...

  15. Effect of an Experimental Direct Pulp-capping Material on the Properties and Osteogenic Differentiation of Human Dental Pulp Stem Cells

    Science.gov (United States)

    Yu, Fan; Dong, Yan; Yang, Yan-Wei; Lin, Ping-Ting; Yu, Hao-Han; Sun, Xiang; Sun, Xue-Fei; Zhou, Huan; Huang, Li; Chen, Ji-Hua

    2016-10-01

    Effective pulp-capping materials must have antibacterial properties and induce dentin bridge formation; however, many current materials do not satisfy clinical requirements. Accordingly, the effects of an experiment pulp-capping material (Exp) composed of an antibacterial resin monomer (MAE-DB) and Portland cement (PC) on the viability, adhesion, migration, and differentiation of human dental pulp stem cells (hDPSCs) were examined. Based on a Cell Counting Kit-8 assay, hDPSCs exposed to Exp extracts showed limited viability at 24 and 48 h, but displayed comparable viability to the control at 72 h. hDPSC treatment with Exp extracts enhanced cellular adhesion and migration according to in vitro scratch wound healing and Transwell migration assays. Exp significantly upregulated the expression of osteogenesis-related genes. The hDPSCs cultured with Exp exhibited higher ALP activity and calcium deposition in vitro compared with the control group. The novel material showed comparable cytocompatibility to control cells and promoted the adhesion, migration, and osteogenic differentiation of hDPSCs, indicating excellent biocompatibility. This new direct pulp-capping material containing MAE-DB and PC shows promise as a potential alternative to conventional materials for direct pulp capping.

  16. Effect of an Experimental Direct Pulp-capping Material on the Properties and Osteogenic Differentiation of Human Dental Pulp Stem Cells

    Science.gov (United States)

    Yu, Fan; Dong, Yan; Yang, Yan-wei; Lin, Ping-ting; Yu, Hao-han; Sun, Xiang; Sun, Xue-fei; Zhou, Huan; Huang, Li; Chen, Ji-hua

    2016-01-01

    Effective pulp-capping materials must have antibacterial properties and induce dentin bridge formation; however, many current materials do not satisfy clinical requirements. Accordingly, the effects of an experiment pulp-capping material (Exp) composed of an antibacterial resin monomer (MAE-DB) and Portland cement (PC) on the viability, adhesion, migration, and differentiation of human dental pulp stem cells (hDPSCs) were examined. Based on a Cell Counting Kit-8 assay, hDPSCs exposed to Exp extracts showed limited viability at 24 and 48 h, but displayed comparable viability to the control at 72 h. hDPSC treatment with Exp extracts enhanced cellular adhesion and migration according to in vitro scratch wound healing and Transwell migration assays. Exp significantly upregulated the expression of osteogenesis-related genes. The hDPSCs cultured with Exp exhibited higher ALP activity and calcium deposition in vitro compared with the control group. The novel material showed comparable cytocompatibility to control cells and promoted the adhesion, migration, and osteogenic differentiation of hDPSCs, indicating excellent biocompatibility. This new direct pulp-capping material containing MAE-DB and PC shows promise as a potential alternative to conventional materials for direct pulp capping. PMID:27698421

  17. Integrating systems biology models and biomedical ontologies

    Directory of Open Access Journals (Sweden)

    de Bono Bernard

    2011-08-01

    Full Text Available Abstract Background Systems biology is an approach to biology that emphasizes the structure and dynamic behavior of biological systems and the interactions that occur within them. To succeed, systems biology crucially depends on the accessibility and integration of data across domains and levels of granularity. Biomedical ontologies were developed to facilitate such an integration of data and are often used to annotate biosimulation models in systems biology. Results We provide a framework to integrate representations of in silico systems biology with those of in vivo biology as described by biomedical ontologies and demonstrate this framework using the Systems Biology Markup Language. We developed the SBML Harvester software that automatically converts annotated SBML models into OWL and we apply our software to those biosimulation models that are contained in the BioModels Database. We utilize the resulting knowledge base for complex biological queries that can bridge levels of granularity, verify models based on the biological phenomenon they represent and provide a means to establish a basic qualitative layer on which to express the semantics of biosimulation models. Conclusions We establish an information flow between biomedical ontologies and biosimulation models and we demonstrate that the integration of annotated biosimulation models and biomedical ontologies enables the verification of models as well as expressive queries. Establishing a bi-directional information flow between systems biology and biomedical ontologies has the potential to enable large-scale analyses of biological systems that span levels of granularity from molecules to organisms.

  18. Tetracycline Loaded Collagen/Hydroxyapatite Composite Materials for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Laura Cristina Rusu

    2015-01-01

    Full Text Available The paper describes the preparation, characterisation, and testing of tetracycline loaded collagen-carboxymethylcellulose/hydroxyapatite ternary composite materials. The synthesis of this drug delivery system consists in two steps: the first step is the mineralization of collagen-carboxymethylcellulose gel while the second step corresponds to the loading of the ternary composite material with tetracycline. The obtained DDS is characterised by physicochemical, morphological, and release behaviour by using FTIR spectroscopy and microscopy, scanning electron microscopy, and UV-VIS spectroscopy. Based on the release study, it can be assumed that tetracycline is released in a prolonged way, assuring at least 6 days of antiseptic properties.

  19. Chewing ability and dental functional status

    NARCIS (Netherlands)

    Nguyen, T.C.; Witter, D.J.; Bronkhorst, E.M.; Gerritsen, A.E.; Creugers, N.H.J.

    2011-01-01

    PURPOSE: The aim of this research was to explore the relationship between chewing ability and dental functional status, perceived oral health-related quality of life, and a number of background variables in a Vietnamese population. MATERIALS AND METHODS: The cluster stratified sample consisted of 2,

  20. Child dental fear and behavior: The role of environmental factors in a hospital cohort

    OpenAIRE

    B S Suprabha; Arathi Rao; Shwetha Choudhary; Ramya Shenoy

    2011-01-01

    Introduction: Information on the origin of dental fear and uncooperative behavior in a child patient is important for behavior management strategy. The effects of environmental factors have been comparatively less studied, especially in an Indian scenario. Objectives: To find the association of (1) age, gender, family characteristics, previous medical, and dental experiences with dental fear and behavior (2) dental fear with dental behavior. Materials and Methods: A cross-sectional questionna...

  1. Biofilm and Dental Biomaterials

    Directory of Open Access Journals (Sweden)

    Marit Øilo

    2015-05-01

    Full Text Available All treatment involving the use of biomaterials in the body can affect the host in positive or negative ways. The microbiological environment in the oral cavity is affected by the composition and shape of the biomaterials used for oral restorations. This may impair the patients’ oral health and sometimes their general health as well. Many factors determine the composition of the microbiota and the formation of biofilm in relation to biomaterials such as, surface roughness, surface energy and chemical composition, This paper aims to give an overview of the scientific literature regarding the association between the chemical, mechanical and physical properties of dental biomaterials and oral biofilm formation, with emphasis on current research and future perspectives.

  2. Optimum gradient material for a functionally graded dental implant using metaheuristic algorithms.

    Science.gov (United States)

    Sadollah, Ali; Bahreininejad, Ardeshir

    2011-10-01

    Despite dental implantation being a great success, one of the key issues facing it is a mismatch of mechanical properties between engineered and native biomaterials, which makes osseointegration and bone remodeling problematical. Functionally graded material (FGM) has been proposed as a potential upgrade to some conventional implant materials such as titanium for selection in prosthetic dentistry. The idea of an FGM dental implant is that the property would vary in a certain pattern to match the biomechanical characteristics required at different regions in the hosting bone. However, matching the properties does not necessarily guarantee the best osseointegration and bone remodeling. Little existing research has been reported on developing an optimal design of an FGM dental implant for promoting long-term success. Based upon remodeling results, metaheuristic algorithms such as the genetic algorithms (GAs) and simulated annealing (SA) have been adopted to develop a multi-objective optimal design for FGM implantation design. The results are compared with those in literature.

  3. Evaluation of simulation learning materials use to fill the gap in Japanese dental English education.

    Science.gov (United States)

    Seki, Naoko; Moross, Janelle; Sunaga, Masayo; Hobo, Koki; Miyoshi, Tomoe; Nitta, Hiroshi; Kinoshita, Atsuhiro; Morio, Ikuko

    2016-01-01

    Even though English is most frequently the common language when the patient's native language differs from that of a dentist, the opportunities for Japanese undergraduate dental students to learn dental English are now quite limited. The purposes of our study were to investigate: the effectiveness and feasibility of the computer-assisted simulation materials as one solution strategy for dental English education in Japan, and the needs and demands for dental English from the learners' side. Interactive simulation materials for medical interviews in English and clinical cases which were translated to English, were delivered via Learning Management System (LMS) to nineteen trainee residents of dentistry (residents). Evaluation for the materials, learners' knowledge and interests in the contents, and ease of operation were obtained by post-questionnaire (response rates were 100% and 95%, respectively). Both questionnaire-surveys received positive feedback toward the materials, yet 47% answered that they lacked the level of knowledge about contents of the medical interview in English. Results were sufficient to suggest that the residents would like to have the opportunity to study or practice medical interview in English, or English related to dentistry, and that the simulation materials could be one of the solution strategies for opportunity provision.

  4. Biomedical and environmental applications of magnetic nanoparticles

    Science.gov (United States)

    Tran, Dai Lam; Le, Van Hong; Linh Pham, Hoai; Nhung Hoang, Thi My; Quy Nguyen, Thi; Luong, Thien Tai; Thu Ha, Phuong; Phuc Nguyen, Xuan

    2010-12-01

    This paper presents an overview of syntheses and applications of magnetic nanoparticles (MNPs) at the Institute of Materials Science, Vietnam Academy of Science and Technology. Three families of oxide MNPs, magnetite, manganite and spinel ferrite materials, were prepared in various ways: coprecipitation, sol-gel and high energy mechanical milling. Basic properties of MNPs were characterized by Vibrating Sample Magnetometer (VSM) and Physical Properties Measurement Systems (PPMS). As for biomedical application, the aim was to design a novel multifunctional, nanosized magnetofluorescent water-dispersible Fe3O4-curcumin conjugate, and its ability to label, target and treat tumor cells was described. The conjugate possesses a magnetic nano Fe3O4 core, chitosan (CS) or Oleic acid (OL) as an outer shell and entrapped curcumin (Cur), serving the dual function of naturally autofluorescent dye as well as antitumor model drug. Fe3O4-Cur conjugate exhibited a high loading cellular uptake with the help of a macrophage, which was clearly visualized dually by Fluorescence Microscope and Laser Scanning Confocal Microscope (LSCM), as well as by magnetization measurement (PPMS). A preliminary magnetic resonance imaging (MRI) study also showed a clear contrast enhancement by using the conjugate. As for the environmental aspect, the use of magnetite MNPs for the removal of heavy toxic metals, such as Arsenic (As) and Lead (Pb), from contaminated water was studied.

  5. Neck and Back Pain in Undergraduate Dental Students at a UK Dental School

    OpenAIRE

    2016-01-01

    Objective Limited data exist on musculoskeletal problems within dental students: we aimed to determine the prevalence of these disorders. Design Single centre cross-sectional study Setting A UK Dental School 2015. Subjects (materials) and methods Students completed a modified Nordic pain questionnaire. Main outcome measures Self-reported frequency and severity of pain, fitness and coping strategies. Results 63% of 390 respondents were female and 75% aged under 23. Seventy-nine percent experie...

  6. Biomedical engineering education--status and perspectives.

    Science.gov (United States)

    Magjarevic, Ratko; Zequera Diaz, Martha L

    2014-01-01

    Biomedical Engineering programs are present at a large number of universities all over the world with an increasing trend. New generations of biomedical engineers have to face the challenges of health care systems round the world which need a large number of professionals not only to support the present technology in the health care system but to develop new devices and services. Health care stakeholders would like to have innovative solutions directed towards solving problems of the world growing incidence of chronic disease and ageing population. These new solutions have to meet the requirements for continuous monitoring, support or care outside clinical settlements. Presence of these needs can be tracked through data from the Labor Organization in the U.S. showing that biomedical engineering jobs have the largest growth at the engineering labor market with expected 72% growth rate in the period from 2008-2018. In European Union the number of patents (i.e. innovation) is the highest in the category of biomedical technology. Biomedical engineering curricula have to adopt to the new needs and for expectations of the future. In this paper we want to give an overview of engineering professions in related to engineering in medicine and biology and the current status of BME education in some regions, as a base for further discussions.

  7. “Struggle to obtain redress”: Women’s experiences of living with symptoms attributed to dental restorative materials and/or electromagnetic fields

    Directory of Open Access Journals (Sweden)

    Lena Mårell

    2016-12-01

    Full Text Available The aim of this study was to explore the experiences of illness and the encounters with health care professionals among women who attributed their symptoms and illness to either dental restorative materials and/or electromagnetic fields, despite the fact that research on health effects from dental fillings or electricity has failed to substantiate the reported symptoms. Thirteen women (aged 37–63 years were invited to the study and a qualitative approach was chosen as the study design, and data were collected using semi-structured interviews. The analysis was conducted with a constant comparative method, according to Grounded Theory. The analysis of the results can be described with the core category, “Struggle to obtain redress,” the two categories, “Stricken with illness” and “A blot in the protocol,” and five subcategories. The core category represents the women's fight for approval and arose in the conflict between their experience of developing a severe illness and the doctors’ or dentists’ rejection of the symptoms as a disease, which made the women feel like malingerers. The informants experienced better support and confirmation from alternative medicine practitioners. However, sick-leave certificates from alternative medicine practitioners were not approved and this led to a continuous cycle of visits in the health care system. To avoid conflicting encounters, it is important for caregivers to listen to the patient's explanatory models and experience of illness, even if a medical answer cannot be given.

  8. “Struggle to obtain redress”: Women’s experiences of living with symptoms attributed to dental restorative materials and/or electromagnetic fields

    Science.gov (United States)

    Mårell, Lena; Lindgren, Monica; Ternulf Nyhlin, Kerstin; Ahlgren, Christina; Berglund, Anders

    2016-01-01

    The aim of this study was to explore the experiences of illness and the encounters with health care professionals among women who attributed their symptoms and illness to either dental restorative materials and/or electromagnetic fields, despite the fact that research on health effects from dental fillings or electricity has failed to substantiate the reported symptoms. Thirteen women (aged 37–63 years) were invited to the study and a qualitative approach was chosen as the study design, and data were collected using semi-structured interviews. The analysis was conducted with a constant comparative method, according to Grounded Theory. The analysis of the results can be described with the core category, “Struggle to obtain redress,” the two categories, “Stricken with illness” and “A blot in the protocol,” and five subcategories. The core category represents the women's fight for approval and arose in the conflict between their experience of developing a severe illness and the doctors’ or dentists’ rejection of the symptoms as a disease, which made the women feel like malingerers. The informants experienced better support and confirmation from alternative medicine practitioners. However, sick-leave certificates from alternative medicine practitioners were not approved and this led to a continuous cycle of visits in the health care system. To avoid conflicting encounters, it is important for caregivers to listen to the patient's explanatory models and experience of illness, even if a medical answer cannot be given. PMID:27938629

  9. NASA Biomedical Informatics Capabilities and Needs

    Science.gov (United States)

    Johnson-Throop, Kathy A.

    2009-01-01

    To improve on-orbit clinical capabilities by developing and providing operational support for intelligent, robust, reliable, and secure, enterprise-wide and comprehensive health care and biomedical informatics systems with increasing levels of autonomy, for use on Earth, low Earth orbit & exploration class missions. Biomedical Informatics is an emerging discipline that has been defined as the study, invention, and implementation of structures and algorithms to improve communication, understanding and management of medical information. The end objective of biomedical informatics is the coalescing of data, knowledge, and the tools necessary to apply that data and knowledge in the decision-making process, at the time and place that a decision needs to be made.

  10. Effects of radio-opacifier addition in dental impression material

    Directory of Open Access Journals (Sweden)

    Mota Eduardo

    2010-01-01

    Full Text Available Objective: The aim of this in vitro study was to determine the effects of barium sulfate addition in two dental impression materials previously proved as radiolucent. Materials and Methods: An irreversible hydrocolloid (IH and polyether (PE were tested for optical density, linear dimension stability and detail reproduction. Statistical Analysis Used: The optical density data were submitted to Kolmogorov-Smirnov normality test and compared with two-way ANOVA and Tukey (alpha=0.05. Results: The results of optical density (pixel were: IH control 45.24 f (±7.6, PE control 54.93 e (±4.45, PE 5Wt% 60.43 d (±6.27, IH 1Wt% 61.54 cd (±5.3, PE 1Wt% 66.9 bc (±5.05, IH 5Wt% 67.17 b (±6.01, PE 10Wt% 84.55 a (±5.14, IH 10Wt% 85.33 a (±5.53. On detail reproduction, polyether control was able to copy the 6 μm line. Adding 1 or 5Wt% of barium sulfate have not change this characteristic. For the irreversible hydrocolloid, the control group was able to copy a line with 14 μm, however, adding 1Wt% barium sulfate, the capability decreased to 22 μm. Adding barium sulfate in the polyether promoted an increase in between the copied lines, for the control, the average distance was 931.6 μm, 936 μm to 1Wt% and 954.5 μm to 5 Wt%. For the IH, the control presented 975 μm in comparison to 987.25 μm for 1 Wt% samples. Conclusion: The addition of barium sulfate was capable of increasing significantly the optical density of tested material, have changed the linear dimension stability, however, have not interfered in detail reproduction only for PE.

  11. Silicatein: nanobiotechnological and biomedical applications.

    Science.gov (United States)

    Schröder, Heinz C; Schlossmacher, Ute; Boreiko, Alexandra; Natalio, Filipe; Baranowska, Malgorzata; Brandt, David; Wang, Xiaohong; Tremel, Wolfgang; Wiens, Matthias; Müller, Werner E G

    2009-01-01

    Silica-based materials are used in many high-tech products including microelectronics, optoelectronics, and catalysts. Siliceous sponges (Demospongiae and Hexactinellida) are unique in their ability to synthesize silica enzymatically. We have cloned the silica-forming enzymes, silicateins, from both demosponges (marine and freshwater sponges) and hexactinellid sponges. The recombinant enzymes allow the synthesis of silica under environmentally benign ambient conditions, while the technical (chemical) production of silica commonly requires high temperatures and pressures, and extremes of pH. Silicateins can be used for the fabrication of highly-ordered inorganic-organic composite materials with defined optical, electrical, and mechanical properties. The simple self-assembly properties of silicateins which are able to form silica and other metal oxides in aqueous solution allow the development of novel products in nano(bio)technology, medicine, and dentistry.

  12. OBTAINING HYSTERESIS LOOPS AT LOW FREQUENCY FOR CHARACTERIZATION OF MATERIALS TO BE USED IN BIOMEDICAL APPLICATIONS

    Directory of Open Access Journals (Sweden)

    Atika Arshad

    2015-05-01

    Full Text Available The promising development of magnetic sensors in biomedical field demands an appropriate level of understanding of the magnetic properties of the materials used in their fabrication. To date only few of the types of magnetic materials are encountered where their magnetic properties, characterization techniques and magnetization behavior are yet to be explored more suitably in the light of their applications. This research work studies the characterization of materials by using a cost effective and simple circuit consisting of inductive transducer and an OP-AMP as a voltage integrator. In this approach the circuit was simulated using PSPICE and experiments have been conducted to achieve the desired results. The simulation and experimental results are obtained for three test materials namely iron, steel and plastic. The novelty lies in applying the simple circuit for material testing and characterization via obtaining simulation results and validating these results through experiment. The magnetic properties in low external magnetic field are studied with materials under test. The magnetization effect of a magneto-inductive sensor is detected in low frequency range for different magnetic core materials. The results have shown magnetization behaviour of magnetic materials due to the variation of permeability and magnetism. The resulted hysteresis loops appeared to have different shapes for different materials. The magnetic hysteresis loop found for iron core demonstrated a bigger coercive force and larger reversals of magnetism than these of steel core, thus obtaining its magnetic saturation at a larger magnetic field strength. The shape of the hysteresis loop itself is found to be varying upon the nature of the material in use. The resulted magnetization behaviors of the materials proved their possible applicability for use in sensing devices. The key concern of this work is found upon selecting the appropriate magnetic materials at the desired

  13. Computational Biomechanics Theoretical Background and BiologicalBiomedical Problems

    CERN Document Server

    Tanaka, Masao; Nakamura, Masanori

    2012-01-01

    Rapid developments have taken place in biological/biomedical measurement and imaging technologies as well as in computer analysis and information technologies. The increase in data obtained with such technologies invites the reader into a virtual world that represents realistic biological tissue or organ structures in digital form and allows for simulation and what is called “in silico medicine.” This volume is the third in a textbook series and covers both the basics of continuum mechanics of biosolids and biofluids and the theoretical core of computational methods for continuum mechanics analyses. Several biomechanics problems are provided for better understanding of computational modeling and analysis. Topics include the mechanics of solid and fluid bodies, fundamental characteristics of biosolids and biofluids, computational methods in biomechanics analysis/simulation, practical problems in orthopedic biomechanics, dental biomechanics, ophthalmic biomechanics, cardiovascular biomechanics, hemodynamics...

  14. Profile of accidents with biological material at a dental school

    Directory of Open Access Journals (Sweden)

    Sandra Aragão de Almeida Sasamoto

    2014-09-01

    Full Text Available http://dx.doi.org/10.4025/actascihealthsci.v36i1.14976 Current research characterizes the epidemiological profile of accidents with biological material (BM that occurred in a government-run dental school and identifies the post-exposure behavior taken by the injured subjects. The cross-sectional retrospective study comprises professors, students and technical-administration personnel who worked in the laboratory from 2001 to 2008 (n = 566. An electronic questionnaire, prepared by software developed for this purpose, was sent to subjects between May and August 2008 for data collection. Ninety-one (34.2% out of 266 participants reported some type of exposure to BM. There was no difference between the occurrence of accidents according to the subjects’ category (p = 0.496 and sex (p = 0.261. Most of the subjects reported cutaneous exposure (76.9% comprising saliva (68.1% and blood (48.3%. The fingers were the body members most affected. Accidents occurred mostly during clinical (34.1% and surgical (30.8% procedures. Although the use of protection equipments was high (82.9%, only 26.4% of subjects reported the accident and only 28.6% sought immediate help. Most of the injured subjects failed to report the accidents and did not comply with the guidelines. Others trivialized basic behavior such as the interruption of the procedure to seek medical assistance.

  15. Functionalized Gold Nanoparticles and Their Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Shree R. Singh

    2011-06-01

    Full Text Available Metal nanoparticles are being extensively used in various biomedical applications due to their small size to volume ratio and extensive thermal stability. Gold nanoparticles (GNPs are an obvious choice due to their amenability of synthesis and functionalization, less toxicity and ease of detection. The present review focuses on various methods of functionalization of GNPs and their applications in biomedical research. Functionalization facilitates targeted delivery of these nanoparticles to various cell types, bioimaging, gene delivery, drug delivery and other therapeutic and diagnostic applications. This review is an amalgamation of recent advances in the field of functionalization of gold nanoparticles and their potential applications in the field of medicine and biology.

  16. Developing biomedical devices design, innovation and protection

    CERN Document Server

    Andreoni, Giuseppe; Colombo, Barbara

    2013-01-01

    During the past two decades incredible progress has been achieved in the instruments and devices used in the biomedical field. This progress stems from continuous scientific research that has taken advantage of many findings and advances in technology made available by universities and industry. Innovation is the key word, and in this context legal protection and intellectual property rights (IPR) are of crucial importance. This book provides students and practitioners with the fundamentals for designing biomedical devices and explains basic design principles. Furthermore, as an aid to the dev

  17. Recommendations for conducting controlled clinical studies of dental restorative materials. Science Committee Project 2/98--FDI World Dental Federation study design (Part I) and criteria for evaluation (Part II) of direct and indirect restorations including onlays and partial crowns.

    Science.gov (United States)

    Hickel, Reinhard; Roulet, Jean-François; Bayne, Stephen; Heintze, Siegward D; Mjör, Ivar A; Peters, Mathilde; Rousson, Valentin; Randall, Ros; Schmalz, Gottfried; Tyas, Martin; Vanherle, Guido

    2007-01-01

    clinical trial designs, guidelines for design, randomization, number of subjects, characteristics of participants, clinical assessment, standards and calibration, categories for assessment, criteria for evaluation, and supplemental documentation. Part 2 of the review considers categories of assessment for esthetic evaluation, functional assessment, biological responses to restorative materials, and statistical analysis of results. The overall review represents a considerable effort to include a range of clinical research interests over the past years. As part of the recognition of the importance of these suggestions, the review is being published simultaneously in identical form in both the Journal of Adhesive Dentistry and Clinical Oral Investigations. Additionally, an extended abstract will be published in the International Dental Journal, giving a link to the web full version. This should help to introduce these considerations more quickly to the scientific community.

  18. Biomedical Applications of Terahertz Spectroscopy and Imaging.

    Science.gov (United States)

    Yang, Xiang; Zhao, Xiang; Yang, Ke; Liu, Yueping; Liu, Yu; Fu, Weiling; Luo, Yang

    2016-10-01

    Terahertz (THz=10(12)Hz) radiation has attracted wide attention for its unprecedented sensing ability and its noninvasive and nonionizing properties. Tremendous strides in THz instrumentation have prompted impressive breakthroughs in THz biomedical research. Here, we review the current state of THz spectroscopy and imaging in various biomedical applications ranging from biomolecules, including DNA/RNA, amino acids/peptides, proteins, and carbohydrates, to cells and tissues. We also address the potential biological effects of THz radiation during its biological applications and propose future prospects for this cutting-edge technology.

  19. Preparation and biomedical applications of chitin and chitosan nanofibers.

    Science.gov (United States)

    Azuma, Kazuo; Ifuku, Shinsuke; Osaki, Tomohiro; Okamoto, Yoshiharu; Minami, Saburo

    2014-10-01

    Chitin (β-(1-4)-poly-N-acetyl-D-glucosamine) is widely distributed in nature and is the second most abundant polysaccharide after cellulose. Chitin occurs in nature as ordered macrofibrils. It is the major structural component in the exoskeleton of crab and shrimp shells and the cell wall of fungi and yeast. As chitin is not readily dissolved in common solvents, it is often converted to its more deacetylated derivative, chitosan. Chitin, chitosan, and its derivatives are widely used in tissue engineering, wound healing, and as functional foods. Recently, easy methods for the preparation of chitin and chitosan nanofibers have been developed, and studies on biomedical applications of chitin and chitosan nanofibers are ongoing. Chitin and chitosan nanofibers are considered to have great potential for various biomedical applications, because they have several useful properties such as high specific surface area and high porosity. This review summarizes methods for the preparation of chitin and chitosan nanofibers. Further, biomedical applications of chitin and chitosan nanofibers in (i) tissue engineering, (ii) wound dressing, (iii) cosmetic and skin health, (iv) stem cell technology, (v) anti-cancer treatments and drug delivery, (vi) anti-inflammatory treatments, and (vii) obesity treatment are summarized. Many studies indicate that chitin and chitosan nanofibers are suitable materials for various biomedical applications.

  20. Effect of dental materials on gluconeogenesis in rat kidney tubules

    NARCIS (Netherlands)

    Reichl, F.X.; Durner, J.; Mückter, H.; Elsenhans, B.; Forth, W.; Kunzelmann, K.H.; Hickel, R.; Spahl, W.; Hume, W.R.; Moes, G.W.

    1999-01-01

    The effect of dental composite components triethyleneglycoldimethacrylate (TEGDMA) and hydroxyethylmethacrylate (HEMA) as well as mercuric chloride (HgCl2) and methylmercury chloride (MeHgCl) on gluconeogenesis was investigated in isolated rat kidney tubules. From starved rats kidney tubules were pr

  1. Periodical Microstructures Based on Novel Piezoelectric Material for Biomedical Applications.

    Science.gov (United States)

    Janusas, Giedrius; Ponelyte, Sigita; Brunius, Alfredas; Guobiene, Asta; Prosycevas, Igoris; Vilkauskas, Andrius; Palevicius, Arvydas

    2015-12-15

    A novel cantilever type piezoelectric sensing element was developed. Cost-effective and simple fabrication design allows the use of this element for various applications in the areas of biomedicine, pharmacy, environmental analysis and biosensing. This paper proposes a novel piezoelectric composite material whose basic element is PZT and a sensing platform where this material was integrated. Results showed that a designed novel cantilever-type element is able to generate a voltage of up to 80 µV at 50 Hz frequency. To use this element for sensing purposes, a four micron periodical microstructure was imprinted. Silver nanoparticles were precipitated on the grating to increase the sensitivity of the designed element, i.e., Surface Plasmon Resonance (SPR) effect appears in the element. To tackle some issues (a lack of sensitivity, signal delays) the element must have certain electronic and optical properties. One possible solution, proposed in this paper, is a combination of piezoelectricity and SPR in a single element.

  2. Calcium phosphates in biomedical applications: materials for the future?

    Directory of Open Access Journals (Sweden)

    Wouter Habraken

    2016-03-01

    Full Text Available Our populations are aging. Some experts predict that 30% of hospital beds will soon be occupied by osteoporosis patients. Statistics show that 20% of patients suffering from an osteoporotic hip fracture do not survive the first year after surgery, all this showing that there is a tremendous need for better therapies for diseased and damaged bone. Human bone consists for about 70% of calcium phosphate (CaP mineral, therefore CaPs are the materials of choice to repair damaged bone. To do this successfully, the process of CaP biomineralization and the interaction of CaPs and biological environment in the body need to be fully understood. First commercial CaP bone graft substitutes were launched 40 years ago, and they are currently often regarded as ‘old biomaterials’ or even as an ‘obsolete’ research topic. Some even talk about ‘stones’. The aim of this manuscript is to highlight the tremendous improvements achieved in CaP materials research in the past 15 years, in particular in the field of biomineralization, as carrier for gene or ion delivery, as biologically active agent, and as bone graft substitute. Besides an outstanding biological performance, CaPs are easily and inexpensively produced, are safe, and can be relatively easily certified for clinical use. As such, CaP materials have won their spurs, but they also offer a great promise for the future.

  3. Dental Care Utilization and Satisfaction of Residential University Students

    Directory of Open Access Journals (Sweden)

    Bamise CT

    2008-01-01

    Full Text Available Aim: The objective of this study was to provide information on the level of utilization and satisfaction of residential university students with the dental services provided by the dental clinic of a teaching hospital. Volunteers and Material: A stratified sampling technique was used to recruit volunteers from the outpatient clinic of the Obafemi Awolowo University Teaching Hospital Complex, Ile-Ife, Nigeria. Information was collected by a self-administered questionnaire composed of questions that measure the level of utilization and satisfaction with the dental services provided. Questionnaires were provided to 650 randomly chosen students residing in the University hostels. There were 39 refusals, and 6 incomplete questionnaires were discarded. This left a sample size of 605 volunteers. Results: Forty seven students (7.8% indicated that they visited the dental hospital within the last 12 months. Males and females utilized the dental services equally, and utilization increased with age and the number of years spent on campus. Anticipation of painful dental treatment, high dental charges, long waiting times and being too busy for a dental visit were cited as the most important impediments to seeking dental treatment. Females expressed greater satisfaction with the services. Conclusion: Dental service utilization among the students was found to be low. Oral health awareness campaigns, improving the quality of the services, and shortening the waiting time are expected to increase service utilization and satisfaction.

  4. Optimization and Data Analysis in Biomedical Informatics

    CERN Document Server

    Pardalos, Panos M; Xanthopoulos, Petros

    2012-01-01

    This volume covers some of the topics that are related to the rapidly growing field of biomedical informatics. In June 11-12, 2010 a workshop entitled 'Optimization and Data Analysis in Biomedical Informatics' was organized at The Fields Institute. Following this event invited contributions were gathered based on the talks presented at the workshop, and additional invited chapters were chosen from world's leading experts. In this publication, the authors share their expertise in the form of state-of-the-art research and review chapters, bringing together researchers from different disciplines

  5. The performance of human dental pulp stem cells on different three-dimensional scaffold materials.

    NARCIS (Netherlands)

    Zhang, W.; Walboomers, X.F.; Kuppevelt, A.H.M.S.M. van; Daamen, W.F.; Bian, Z.; Jansen, J.A.

    2006-01-01

    The aim of this study was to investigate the in vitro and in vivo behavior of human dental pulp stem cells (DPSCs) isolated from impacted third molars, when seeded onto different 3-dimensional (3-D) scaffold materials: i.e. a spongeous collagen, a porous ceramic, and a fibrous titanium mesh. Scaffol

  6. Cytogenetic genotoxic investigation in peripheral blood lymphocytes of subjects with dental composite restorative filling materials.

    Science.gov (United States)

    Pettini, F; Savino, M; Corsalini, M; Cantore, S; Ballini, A

    2015-01-01

    Dental composite resins are biomaterials commonly used to aesthetically restore the structure and function of teeth impaired by caries, erosion, or fracture. Residual monomers released from resin restorations as a result of incomplete polymerization processes interact with living oral tissues. The objective of this study was to evaluate the genotoxicity of a common dental composite material (Enamel Plus-HFO), in subjects with average 13 filled teeth with the same material, compared to a control group (subjects having neither amalgam nor composite resin fillings). Genotoxicity assessment of composite materials was carried out in vitro in human peripheral blood leukocytes using sister-chromatid exchange (SCE) and chromosomal aberrations (CA) cytogenetic tests. The results of correlation and multiple regression analyses confirmed the absence of a relationship between SCE/cell, high frequency of SCE(HFC) or CA frequencies and exposure to dental composite materials. These results indicate that composite resins used for dental restorations differ extensively in vivo in their cytotoxic and genotoxic potential and in their ability to affect chromosomal integrity, cell-cycle progression, DNA replication and repair.

  7. [Scientometrics and bibliometrics of biomedical engineering periodicals and papers].

    Science.gov (United States)

    Zhao, Ping; Xu, Ping; Li, Bingyan; Wang, Zhengrong

    2003-09-01

    This investigation was made to reveal the current status, research trend and research level of biomedical engineering in Chinese mainland by means of scientometrics and to assess the quality of the four domestic publications by bibliometrics. We identified all articles of four related publications by searching Chinese and foreign databases from 1997 to 2001. All articles collected or cited by these databases were searched and statistically analyzed for finding out the relevant distributions, including databases, years, authors, institutions, subject headings and subheadings. The source of sustentation funds and the related articles were analyzed too. The results showed that two journals were cited by two foreign databases and five Chinese databases simultaneously. The output of Journal of Biomedical Engineering was the highest. Its quantity of original papers cited by EI, CA and the totality of papers sponsored by funds were higher than those of the others, but the quantity and percentage per year of biomedical articles cited by EI were decreased in all. Inland core authors and institutions had come into being in the field of biomedical engineering. Their research topics were mainly concentrated on ten subject headings which included biocompatible materials, computer-assisted signal processing, electrocardiography, computer-assisted image processing, biomechanics, algorithms, electroencephalography, automatic data processing, mechanical stress, hemodynamics, mathematical computing, microcomputers, theoretical models, etc. The main subheadings were concentrated on instrumentation, physiopathology, diagnosis, therapy, ultrasonography, physiology, analysis, surgery, pathology, method, etc.

  8. Molecular engineering of polymer actuators for biomedical and industrial use

    Science.gov (United States)

    Banister, Mark; Eichorst, Rebecca; Gurr, Amy; Schweitzer, Georgette; Geronov, Yordan; Rao, Pavalli; McGrath, Dominic

    2012-04-01

    Five key materials engineering components and how each component impacted the working performance of a polymer actuator material are investigated. In our research we investigated the change of actuation performance that occurred with each change we made to the material. We investigated polymer crosslink density, polymer chain length, polymer gelation, type and density of reactive units, as well as the addition of binders to the polymer matrix. All five play a significant role and need to be addressed at the molecular level to optimize a polymer gel for use as a practical actuator material for biomedical and industrial use.

  9. Child dental fear and behavior: The role of environmental factors in a hospital cohort

    Directory of Open Access Journals (Sweden)

    B S Suprabha

    2011-01-01

    Full Text Available Introduction: Information on the origin of dental fear and uncooperative behavior in a child patient is important for behavior management strategy. The effects of environmental factors have been comparatively less studied, especially in an Indian scenario. Objectives: To find the association of (1 age, gender, family characteristics, previous medical, and dental experiences with dental fear and behavior (2 dental fear with dental behavior. Materials and Methods: A cross-sectional questionnaire study involving 125 children aged between 7 and 14 years undergoing dental treatment under local anesthesia. The parent completed a questionnaire on family situation, medical history, and past dental experiences of the child. Child′s dental fear was recorded using Children′s Fear Survey Schedule-Dental Subscale and behavior was rated using Frankl Behaviour Rating Scale. Statistical Analysis: Data were analyzed using chi square test and binary logistic regression analysis. Results: Unpleasant experience in dental clinic and age of the child significantly influenced dental behavior. Visited pediatrician in the past one year, prior history of hospital admission, previous visit to dentist, experience at the first dental visit, and age of the child were contributing factors for dental fear. There was also significant association between dental fear levels and behavior. Conclusions: In 7 to 14 year olds, dental fear influences dental behavior, but the factors affecting them are not the same. Although dental fear decreases and dental behavior improves with age, experiences at the previous dental visits seem to influence both dental fear and behavior. Past medical experiences are likely to influence dental fear but not dental behavior.

  10. Immortalized gingival fibroblasts as a cytotoxicity test model for dental materials.

    Science.gov (United States)

    Illeperuma, Rasika P; Park, Young J; Kim, Jin M; Bae, Jung Y; Che, Zhong M; Son, Hwa K; Han, Mi R; Kim, Kwang M; Kim, Jin

    2012-03-01

    In vitro cytotoxicity test is an initial step to identify the harmful effects of new dental materials. Aim of this study was to develop a stable human cell line derived from normal gingival fibroblasts (hNOF) and to assess its feasibility in in vitro cytotoxicity testing. Immortalized human gingival fibroblasts (hTERT-hNOF) were successfully established with human telomerase reverse transcriptase gene transfection, preserving its phenotypical characteristics, replicative potential and biological properties. Utilizing standard cytotoxicity test modeling and dental materials, hTERT-hNOF were evaluated for their feasibility in cytotoxicity testing, compared with hNOF and L929 cells. Similar pattern of cytotoxic response was observed among hNOF, hTERT-hNOF and L929 cells. Cytotoxicity response of hTERT-hNOF was significantly similar to hNOF, moreover hTERT-hNOF and hNOF were found to be more sensitive towards the tested dental materials compared to L929 cells. This study suggested that hTERT-hNOF is an effective cytotoxic test model for dental materials.

  11. First-year dental students’ motivation and attitudes for choosing the dental profession

    Directory of Open Access Journals (Sweden)

    Nadya Avramova

    2014-11-01

    Full Text Available Objective. To determine first-year dental students’ current motivation and attitudes for choosing the dental profession at the Faculty of Dental Medicine, Medical University – Sofia, Bulgaria. Material and methods. An anonymous questionnaire, consisting of 12 questions about students’ socio-demographic profile and their motivation for choosing dentistry, was administered to 119 first-year dental students at the Faculty of Dental Medicine of the Medical University of Sofia. The study was conducted at the beginning of the 2012-2013 academic year. The data was processed and analyzed with the following software: Microsoft Windows Server 2008 R2; Microsoft SQL Server 2008; Internet Information Server 7.5.; Microsoft SharePoint Server 2010. Results. The majority of the students (73% were self-motivated for choosing dentistry as a career; 61% of them did not have relatives in the medical profession; 43% chose dental medicine because it is a prestigious, humane and noble profession; 50% – for financial security; 59% – because of the independence that it provides. There were no significant differences in the motivation between males and females. Conclusion. Independence, financial security and ‘prestige’ were the predominant motivating factors in this group of first-year dental students. Determining the reasons for choosing dentistry has important implications for the selection and training of students as well as for their future job satisfaction.

  12. [Dental materials. A critical assessment from the viewpoint of alternative medicine].

    Science.gov (United States)

    Weilenmann, Urs

    2009-01-01

    Practical experience with unconventional treatments suggests that the paradigm used by conventional medical science to assess the impact of dental materials must be broadened. First, several diagnostic methods commonly employed to evaluate allergies and toxicological burdens are described and subjected to a critical analysis. These diagnostics include test methods used in the field of complementary medicine in addition to the traditional epicutaneous tests, the Lymphocyte Transformation Test and quantitative analysis of blood and urine. Finally, the fundamentals of toxicology in the low-dose range are discussed; in this context special attention is paid to possible factors enhancing the effect of various substance groups. The impact of dental materials is also viewed from the perspective of environmental toxicology. In addition, the authors discuss various paradigms for obtaining evidence of multifactorial causes and show why nonuniform results are obtained with dental materials. Reference is also made to new theories broadening our understanding of biological processes such as the Biphoton Theory, which has been the subject of increased discussion among quantum physicists in recent years. It becomes evident in this context that there are to date no evidence-based methods for demonstrating the absolute non-toxicity of dental materials. Finally, it is shown - on the basis of various reports provided by a practitioner of complementary medicine in private practice - that, in patients with chronic diseases, unconventional therapies integrating these insights may by the only effective therapeutic options to succeed.

  13. Nanomedicine: magnetic nanoparticles and their biomedical applications.

    Science.gov (United States)

    Banerjee, Reshmi; Katsenovich, Yelena; Lagos, Leonel; McIintosh, M; Zhang, Xueji; Li, Chen-Zhong

    2010-01-01

    During this past decade, science and engineering have seen a rapid increase in interest for nanoscale materials with dimensions less than 100 nm, which lie in the intermediate state between atoms and bulk (solid) materials. Their attributes are significantly altered relative to the corresponding bulk materials as they exhibit size dependent behavior such as quantum size effects (depending on bulk Bohr radius), optical absorption and emission, coulomb staircase behavior (electrical transport), superparamagnetism and various unique properties. They are active components of ferrofluids, recording tape, flexible disk recording media along with potential future applications in spintronics: a new paradigm of electronics utilizing intrinsic charge and spin of electrons for ultra-high-density data storage and quantum computing. They are used in a gamut of biomedical applications: bioseparation of biological entities, therapeutic drugs and gene delivery, radiofrequency-induced destruction of cells and tumors (hyperthermia), and contrast-enhancement agents for magnetic resonance imaging (MRI). The magnetic nanoparticles have optimizable, controllable sizes enabling their comparison to cells (10-100 µm), viruses (20-250 nm), proteins (3-50 nm), and genes (10-100 nm). Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) provide necessary characterization methods that enable accurate structural and functional analysis of interaction of the biofunctional particles with the target bioentities. The goal of the present discussion is to provide a broad review of magnetic nanoparticle research with a special focus on the synthesis, functionalization and medical applications of these particles, which have been carried out during the past decade, and to examine several prospective directions.

  14. Compressive fatigue limit of four types of dental restorative materials.

    Science.gov (United States)

    Chen, Song; Öhman, Caroline; Jefferies, Steven R; Gray, Holly; Xia, Wei; Engqvist, Håkan

    2016-08-01

    The purpose of this study was to evaluate the quasi-static compressive strength and the compressive fatigue limit of four different dental restorative materials, before and after aging in distilled water for 30 days. A conventional glass ionomer cement (Fuji IX GP; IG), a zinc-reinforced glass ionomer cement (Chemfil rock; CF), a light curable resin-reinforced glass ionomer cement (Fuji II LC; LC) and a resin-based composite (Quixfil; QF) were investigated. Cylindrical specimens (4mm in diameter and 6mm in height) were prepared according to the manufacturer׳s instructions. The compressive fatigue limit was obtained using the staircase method. Samples were tested in distilled water at 37°C, at a frequency of 10Hz with 10(5) cycles set as run-out. 17 fatigue samples were tested for each group. Two-way ANOVA and one-way ANOVA followed by Tukey׳s post-hoc test were used to analyze the results. Among the four types of materials, the resin-based composite exhibited the highest compressive strength (244±13.0MPa) and compressive fatigue limit (134±7.8MPa), followed by the light-cured resin reinforced glass ionomer cement (168±8.5MPa and 92±6.6MPa, respectively) after one day of storage in distilled water. After being stored for 30 days, all specimens showed an increase in compressive strength. Aging showed no effect on the compressive fatigue limit of the resin-based composite and the light-cured resin reinforced glass ionomer cement, however, the conventional glass ionomer cements showed a drastic decrease (37% for IG, 31% for CF) in compressive fatigue limit. In conclusion, in the present study, resin modified GIC and resin-based composite were found to have superior mechanical properties to conventional GIC.

  15. 78 FR 36556 - National Institute of Dental and Craniofacial Research; Notice of Closed Meeting

    Science.gov (United States)

    2013-06-18

    ... HUMAN SERVICES National Institutes of Health National Institute of Dental and Craniofacial Research... commercial property such as patentable material, and personal information concerning individuals associated... personal privacy. Name of Committee: National Institute of Dental and Craniofacial Research...

  16. 78 FR 59708 - National Institute of Dental and Craniofacial Research; Notice of Closed Meeting

    Science.gov (United States)

    2013-09-27

    ... HUMAN SERVICES National Institutes of Health National Institute of Dental and Craniofacial Research... commercial property such as patentable material, and personal information concerning individuals associated... personal privacy. Name of Committee: National Institute of Dental and Craniofacial Research...

  17. 77 FR 74676 - National Institute of Dental and Craniofacial Research; Notice of Closed Meeting

    Science.gov (United States)

    2012-12-17

    ... HUMAN SERVICES National Institutes of Health National Institute of Dental and Craniofacial Research... commercial property such as patentable material, and personal information concerning individuals associated... personal privacy. Name of Committee: National Institute of Dental and Craniofacial Research...

  18. 77 FR 6812 - National Institute of Dental and Craniofacial Research, Notice of Closed Meeting

    Science.gov (United States)

    2012-02-09

    ... HUMAN SERVICES National Institutes of Health National Institute of Dental and Craniofacial Research... commercial property such as patentable material, and personal information concerning individuals associated... personal privacy. Name of Committee: National Institute of Dental and Craniofacial Research...

  19. 77 FR 11563 - National Institute of Dental and Craniofacial Research; Notice of Closed Meeting

    Science.gov (United States)

    2012-02-27

    ... HUMAN SERVICES National Institutes of Health National Institute of Dental and Craniofacial Research... commercial property such as patentable material, and personal information concerning individuals associated... personal privacy. Name of Committee: National Institute of Dental and Craniofacial Research...

  20. 75 FR 28028 - National Institute of Dental and Craniofacial Research; Notice of Closed Meeting

    Science.gov (United States)

    2010-05-19

    ... HUMAN SERVICES National Institutes of Health National Institute of Dental and Craniofacial Research... commercial property such as patentable material, and personal information concerning individuals associated... personal privacy. Name of Committee: National Institute of Dental and Craniofacial Research...

  1. 76 FR 58284 - National Institute of Dental and Craniofacial Research; Notice of Closed Meetings

    Science.gov (United States)

    2011-09-20

    ... HUMAN SERVICES National Institutes of Health National Institute of Dental and Craniofacial Research... commercial property such as patentable material, and personal information concerning individuals associated... personal privacy. Name of Committee: National Institute of Dental and Craniofacial Research...

  2. BIG: a Grid Portal for Biomedical Data and Images

    Directory of Open Access Journals (Sweden)

    Giovanni Aloisio

    2004-06-01

    Full Text Available Modern management of biomedical systems involves the use of many distributed resources, such as high performance computational resources to analyze biomedical data, mass storage systems to store them, medical instruments (microscopes, tomographs, etc., advanced visualization and rendering tools. Grids offer the computational power, security and availability needed by such novel applications. This paper presents BIG (Biomedical Imaging Grid, a Web-based Grid portal for management of biomedical information (data and images in a distributed environment. BIG is an interactive environment that deals with complex user's requests, regarding the acquisition of biomedical data, the "processing" and "delivering" of biomedical images, using the power and security of Computational Grids.

  3. Three-dimensional assessment of dental casts' occlusal surfaces using two impression materials.

    Science.gov (United States)

    Tarawneh, F M; Panos, P G; Athanasiou, A E

    2008-11-01

    The aim of this study was to assess by means of a three-dimensional computed tomography scanning system the occlusal surface characteristics of dental casts made using two different impression materials. Alginate and polyvinyl siloxane impressions were taken of 20 dental students resulting in 40 dental casts. The casts were paired for each student separately so that each pair consisted of an alginate poured cast and a polyvinyl siloxane poured out cast. The casts were scanned using FlashCT scanner and for each cast, a three-dimensional digital image was obtained. The digitized casts were processed using the three-dimensional imaging software Geomagic Studio 9. A total of 464 paired teeth were digitally separated and superimposed. For each tooth, two measurements were obtained corresponding to the two different impression materials used. The two sets of volumes for all digitally separated teeth were compared and analysed using the Wilcoxon signed test. Larger volume measurements were obtained for teeth separated from alginate poured out casts than from their corresponding ones from polyvinyl siloxane casts (P = 0.005). When the teeth were divided into the groups of incisors, canines and premolars/molars, only the last one exhibited significant difference (P = 0.00). The mean difference between the volumes measured for all 464 teeth separated was 0.041 mm(3) (+/-0.33). The occlusal surfaces of teeth appear differently in dental casts depending on the impression materials used. Impressions of dental casts should be utilized with caution in relation to their research application and in reference with dental wear studies.

  4. [Functional dental anatomy and amalgam].

    Science.gov (United States)

    Tavernier, B; Colon, P

    1989-01-01

    Very often, the functional dental anatomy are reflected during the rehabilitation of posterior quadrants. However, the placement, the shaping in correct relation of the different dental components are indispensable conditions to respect, in order to achieve an adequate integration of the restoration within the neuro-muscular system. A clinical protocol is proposed in order to reconcile the anatomical and biological prerequisite and the setting time of modern alloys.

  5. Evaluating the Effect of Dental Filling Material and Filling Depth on the Strength and Deformation of Filled Teeth

    OpenAIRE

    Seifollah Gholampour; Ghazale Zoorazma; Ehsan Shakouri

    2016-01-01

    ackground and aim: It is important to evaluate the effect of the type of filling material on deformation and strength of tooth after filling and also the effect of filling depth on quality of restoration of a decayed tooth. Material and Methods: The Orthopantomogram (OPG) of the first and second molars of a 28-year-old man was made and the teeth were 3D modeled. The stress-deformation analysis was then performed on the models in the three states of normal tooth, tooth filled with amalgam and ...

  6. Biomedical Big Data Training Collaborative (BBDTC): An effort to bridge the talent gap in biomedical science and research.

    Science.gov (United States)

    Purawat, Shweta; Cowart, Charles; Amaro, Rommie E; Altintas, Ilkay

    2016-06-01

    The BBDTC (https://biobigdata.ucsd.edu) is a community-oriented platform to encourage high-quality knowledge dissemination with the aim of growing a well-informed biomedical big data community through collaborative efforts on training and education. The BBDTC collaborative is an e-learning platform that supports the biomedical community to access, develop and deploy open training materials. The BBDTC supports Big Data skill training for biomedical scientists at all levels, and from varied backgrounds. The natural hierarchy of courses allows them to be broken into and handled as modules. Modules can be reused in the context of multiple courses and reshuffled, producing a new and different, dynamic course called a playlist. Users may create playlists to suit their learning requirements and share it with individual users or the wider public. BBDTC leverages the maturity and design of the HUBzero content-management platform for delivering educational content. To facilitate the migration of existing content, the BBDTC supports importing and exporting course material from the edX platform. Migration tools will be extended in the future to support other platforms. Hands-on training software packages, i.e., toolboxes, are supported through Amazon EC2 and Virtualbox virtualization technologies, and they are available as: (i) downloadable lightweight Virtualbox Images providing a standardized software tool environment with software packages and test data on their personal machines, and (ii) remotely accessible Amazon EC2 Virtual Machines for accessing biomedical big data tools and scalable big data experiments. At the moment, the BBDTC site contains three open Biomedical big data training courses with lecture contents, videos and hands-on training utilizing VM toolboxes, covering diverse topics. The courses have enhanced the hands-on learning environment by providing structured content that users can use at their own pace. A four course biomedical big data series is planned

  7. Biomedical Big Data Training Collaborative (BBDTC): An effort to bridge the talent gap in biomedical science and research

    Science.gov (United States)

    Purawat, Shweta; Cowart, Charles; Amaro, Rommie E.; Altintas, Ilkay

    2016-01-01

    The BBDTC (https://biobigdata.ucsd.edu) is a community-oriented platform to encourage high-quality knowledge dissemination with the aim of growing a well-informed biomedical big data community through collaborative efforts on training and education. The BBDTC collaborative is an e-learning platform that supports the biomedical community to access, develop and deploy open training materials. The BBDTC supports Big Data skill training for biomedical scientists at all levels, and from varied backgrounds. The natural hierarchy of courses allows them to be broken into and handled as modules. Modules can be reused in the context of multiple courses and reshuffled, producing a new and different, dynamic course called a playlist. Users may create playlists to suit their learning requirements and share it with individual users or the wider public. BBDTC leverages the maturity and design of the HUBzero content-management platform for delivering educational content. To facilitate the migration of existing content, the BBDTC supports importing and exporting course material from the edX platform. Migration tools will be extended in the future to support other platforms. Hands-on training software packages, i.e., toolboxes, are supported through Amazon EC2 and Virtualbox virtualization technologies, and they are available as: (i) downloadable lightweight Virtualbox Images providing a standardized software tool environment with software packages and test data on their personal machines, and (ii) remotely accessible Amazon EC2 Virtual Machines for accessing biomedical big data tools and scalable big data experiments. At the moment, the BBDTC site contains three open Biomedical big data training courses with lecture contents, videos and hands-on training utilizing VM toolboxes, covering diverse topics. The courses have enhanced the hands-on learning environment by providing structured content that users can use at their own pace. A four course biomedical big data series is planned

  8. Dental Calculus Arrest of Dental Caries

    Science.gov (United States)

    Keyes, Paul H.; Rams, Thomas E.

    2016-01-01

    Background An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human teeth for the presence and location of dental caries, dental calculus, and dental plaque biofilms. Materials and methods A total of 1,200 teeth were preserved in 10% buffered formal saline, and viewed while moist by a single experienced examiner using a research stereomicroscope at 15-25× magnification. Representative teeth were sectioned and photographed, and their dental plaque biofilms subjected to gram-stain examination with light microscopy at 100× magnification. Results Dental calculus was observed on 1,140 (95%) of the extracted human teeth, and no dental carious lesions were found underlying dental calculus-covered surfaces on 1,139 of these teeth. However, dental calculus arrest of dental caries was found on one (0.54%) of 187 evaluated teeth that presented with unrestored proximal enamel caries. On the distal surface of a maxillary premolar tooth, dental calculus mineralization filled the outer surface cavitation of an incipient dental caries lesion. The dental calculus-covered carious lesion extended only slightly into enamel, and exhibited a brown pigmentation characteristic of inactive or arrested dental caries. In contrast, the tooth's mesial surface, without a superficial layer of dental calculus, had a large carious lesion going through enamel and deep into dentin. Conclusions These observations further document the potential protective effects of dental calculus mineralization against dental caries. PMID:27446993

  9. Developing core dental public health competencies for predoctoral dental and dental hygiene students.

    Science.gov (United States)

    Mascarenhas, Ana Karina; Atchison, Kathryn Ann

    2015-01-01

    Dental professionals are an "underutilized" workforce, when it comes to advocating for prevention and wellness in populations. The goal of this HRSA-funded project is to develop dental public health (DPH) competencies and curriculum for US predoctoral dental and dental hygiene programs. These competencies and accompanying curriculum are designed to better prepare the oral health workforce to meet the needs of the entire population, including the chronically underserved, those challenged by poor health literacy, or communities encountering barriers to accessing oral health care. By increasing the DPH competency of all graduating dental providers, in population-based approaches to preventing oral diseases rather than the existing exclusive focus on treatment, the number of providers who can respond to a population or the public's unmet needs and challenges, both in private practices and publicly supported clinics, will increase. This paper describes the competency development process and the eight competencies that were identified.

  10. Femtosecond laser micromachining of dielectric materials for biomedical applications

    Science.gov (United States)

    Farson, Dave F.; Choi, Hae Woon; Zimmerman, Burr; Steach, Jeremy K.; Chalmers, Jeffery J.; Olesik, Susan V.; Lee, L. James

    2008-03-01

    Techniques for microfluidic channel fabrication in soda-lime glass and fused quartz using femtosecond laser ablation and ablation in conjunction with polymer coating for surface roughness improvement were tested. Systematic experiments were done to characterize how process variables (laser fluence, scanning speed and focus spot overlap, and material properties) affect the machining feature size and quality. Laser fluence and focus spot overlap showed the strongest influence on channel depth and roughness. At high fluence, the surface roughness was measured to be between 395 nm and 731 nm RMS. At low fluence, roughness decreased to 100 nm-350 nm RMS and showed a greater dependence on overlap. The surface roughness of laser ablation was also dependent on the material properties. For the same laser ablation parameters, soda-lime glass surfaces were smoother than fused quartz. For some applications, especially those using quartz, smoother channels are desired. A hydroxyethyl methacrylate (HEMA) polymer coating was applied and the roughness of the coated channels was improved to 10-50 nm RMS.

  11. Processing of New Materials by Additive Manufacturing: Iron-Based Alloys Containing Silver for Biomedical Applications

    Science.gov (United States)

    Niendorf, Thomas; Brenne, Florian; Hoyer, Peter; Schwarze, Dieter; Schaper, Mirko; Grothe, Richard; Wiesener, Markus; Grundmeier, Guido; Maier, Hans Jürgen

    2015-07-01

    In the biomedical sector, production of bioresorbable implants remains challenging due to improper dissolution rates or deficient strength of many candidate alloys. Promising materials for overcoming the prevalent drawbacks are iron-based alloys containing silver. However, due to immiscibility of iron and silver these alloys cannot be manufactured based on conventional processing routes. In this study, iron-manganese-silver alloys were for the first time synthesized by means of additive manufacturing. Based on combined mechanical, microscopic, and electrochemical studies, it is shown that silver particles well distributed in the matrix can be obtained, leading to cathodic sites in the composite material. Eventually, this results in an increased dissolution rate of the alloy. Stress-strain curves showed that the incorporation of silver barely affects the mechanical properties.

  12. Micro and Nano Manipulations for Biomedical Applications

    CERN Document Server

    Yih, Tachung C

    2007-01-01

    Taking bio-device research and development to "the next level," this book covers the latest advances in biomedical microelectromechanical systems (MEMS) and nanoelectromechanical systems (NEMS). The book presents new developments in the synthesis and use of metallic nanoparticles in bio-sensing and drug delivery, including quantum dots semiconductors nanocrystals.

  13. Biomedical engineering at UCT - challenges and opportunities.

    Science.gov (United States)

    Douglas, Tania S

    2012-03-02

    The biomedical engineering programme at the University of Cape Town has the potential to address some of South Africa's unique public health challenges and to contribute to growth of the local medical device industry, directly and indirectly, through research activities and postgraduate education. Full realisation of this potential requires engagement with the clinical practice environment and with industry.

  14. Techniques and Materials Used by General Dentists during Root Canal Treatment Procedures: Findings from the National Dental Practice-Based Research Network

    Science.gov (United States)

    Eleazer, Paul D.; Gilbert, Gregg H.; Funkhouser, Ellen; Reams, G.J.; Law, A.S.; Benjamin, Paul L.

    2015-01-01

    Background Little is known about which materials and techniques general dentists (GDs) use during root canal procedures. The objectives were to: (1) quantify GD’s use of specific endodontic armamentarium; (2) quantify inappropriate use; and (3) ascertain if inappropriate use is associated with dentists’ practice characteristics. Methods GDs in the National Dental Practice-Based Research Network reported in a questionnaire materials and techniques they use during root canal procedures. Results 1,490 (87%) of eligible GDs participated. Most (93%; n=1,383) used sodium hypochlorite to irrigate. The most commonly used sealers were zinc oxide-eugenol (43%) and resin (40%), followed by calcium hydroxide (26%). A majority (62%; n=920) used a compaction obturation technique; 36% (n=534) used a carrier-based method. Most (96%; n=1,423) used gutta percha as a filler; 5% used paste fillers. Few used irrigants (n=46), sealers (n=4), techniques (n=49) or fillers (n=10) that investigators classified as ‘inappropriate’. Conclusions GDs use a broad range of endodontic techniques and materials, often adapting to newer technologies as they become available. Few GDs use armamentarium that the investigators classified as inappropriate. Practical Implications GDs use many types of endodontic techniques and materials, but only a very small percentage is not appropriate. PMID:26562726

  15. Hydroxyapatite coatings for biomedical applications

    CERN Document Server

    Zhang, Sam

    2013-01-01

    Hydroxyapatite coatings are of great importance in the biological and biomedical coatings fields, especially in the current era of nanotechnology and bioapplications. With a bonelike structure that promotes osseointegration, hydroxyapatite coating can be applied to otherwise bioinactive implants to make their surface bioactive, thus achieving faster healing and recovery. In addition to applications in orthopedic and dental implants, this coating can also be used in drug delivery. Hydroxyapatite Coatings for Biomedical Applications explores developments in the processing and property characteri

  16. Periodical Microstructures Based on Novel Piezoelectric Material for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Giedrius Janusas

    2015-12-01

    Full Text Available A novel cantilever type piezoelectric sensing element was developed. Cost-effective and simple fabrication design allows the use of this element for various applications in the areas of biomedicine, pharmacy, environmental analysis and biosensing. This paper proposes a novel piezoelectric composite material whose basic element is PZT and a sensing platform where this material was integrated. Results showed that a designed novel cantilever-type element is able to generate a voltage of up to 80 µV at 50 Hz frequency. To use this element for sensing purposes, a four micron periodical microstructure was imprinted. Silver nanoparticles were precipitated on the grating to increase the sensitivity of the designed element, i.e., Surface Plasmon Resonance (SPR effect appears in the element. To tackle some issues (a lack of sensitivity, signal delays the element must have certain electronic and optical properties. One possible solution, proposed in this paper, is a combination of piezoelectricity and SPR in a single element.

  17. Biomedical Engineering and Cognitive Science Secondary Science Curriculum Development: A Three Year Study

    Science.gov (United States)

    Klein, Stacy S.; Sherwood, Robert D.

    2005-01-01

    This study reports on a multi-year effort to create and evaluate cognitive-based curricular materials for secondary school science classrooms. A team of secondary teachers, educational researchers, and academic biomedical engineers developed a series of curriculum units that are based in biomedical engineering for secondary level students in…

  18. Industry-Sponsored Dental Health Teaching Aids: Selection Criteria and Program Examples.

    Science.gov (United States)

    Travis, Donna L.

    1982-01-01

    Ten questions are provided to facilitate selection and evaluation of materials for a dental health curriculum. Examples of industry-sponsored dental health programs available free or at minimal cost are given. (JN)

  19. Peptides and metallic nanoparticles for biomedical applications.

    NARCIS (Netherlands)

    Kogan, M.J.; Olmedo, I.; Hosta, L.; Guerrero, A.R.; Cruz Ricondo, L.J.; Albericio, F.

    2007-01-01

    In this review, we describe the contribution of peptides to the biomedical applications of metallic nanoparticles. We also discuss strategies for the preparation of peptide-nanoparticle conjugates and the synthesis of the peptides and metallic nanoparticles. An overview of the techniques used for th

  20. Biomedical Visual Computing: Case Studies and Challenges

    KAUST Repository

    Johnson, Christopher

    2012-01-01

    Advances in computational geometric modeling, imaging, and simulation let researchers build and test models of increasing complexity, generating unprecedented amounts of data. As recent research in biomedical applications illustrates, visualization will be critical in making this vast amount of data usable; it\\'s also fundamental to understanding models of complex phenomena. © 2012 IEEE.

  1. Clinical analysis of biocompatibility of different dental restorative materials and 3 kinds of materials to ifll the proximal dental caries of accessional teeth%不同牙科修复材料生物相容性及3种材料充填恒磨牙邻面龋的临床分析

    Institute of Scientific and Technical Information of China (English)

    马海英

    2016-01-01

    ObjectiveTo analyze the clinical effect of different dental restorative materials on the proximal dental caries of accessional teeth.MethodA retrospective analysis of clinical data of 444 patients with proximal dental caries of accessional teeth treated in our hospital from May 2010 to May 2012 was performed, according to the different iflling materials, the patients were divided into group A (glass-ionomer cement), group B (light-cured composite resin) and group C (silver amalgam), analyzed the success rate of different dental restorative materials.ResultFollowed-up 1 and 3 years respectively, the success rate of group A was signiifcantly lower than that of group B and group C (P0.05); after 3 years of restoration, the success rate of group B was higher than group C (P<0.05).ConclusionLight-cured composite resin is helpful to improve the success rate of proximal dental caries of accessional teeth, and it is worth to be popularized in clinic.%目的:研究并分析不同牙科修复材料充填恒磨牙邻面龋的临床效果。方法回顾性分析2010年5月至2012年5月收治的444例恒磨牙邻面龋患者的临床资料。按照充填材料不同将入选患者分为A组(玻璃离子水门汀充填)、B组(光固化复合树脂充填)、C组(银汞合金充填),分析不同牙科修复材料对患牙的修复成功率。结果修复后1年和3年复诊,A组患牙修复成功率明显低于B组和C组(P<0.05)。修复后1年,B组与C组患牙修复成功率比较差异无显著性(P>0.05);修复后3年,B组患牙修复成功率高于C组(P<0.05)。结论光固化复合树脂有助于提高恒磨牙邻面龋的修复成功率,值得临床推广。

  2. [Development and application of electroanalytical methods in biomedical fields].

    Science.gov (United States)

    Kusu, Fumiyo

    2015-01-01

    To summarize our electroanalytical research in the biomedical field over the past 43 years, this review describes studies on specular reflection measurement, redox potential determination, amperometric acid sensing, HPLC with electrochemical detection, and potential oscillation across a liquid membrane. The specular reflection method was used for clarifying the adsorption of neurotransmitters and their related drugs onto a gold electrode and the interaction between dental alloys and compound iodine glycerin. A voltammetric screening test using a redox potential for the antioxidative effect of flavonoids was proposed. Amperometric acid sensing based on the measurement of the reduction prepeak current of 2-methyl-1,4-naphthoquinone (VK3) or 3,5-di-tert-buty1-1,2-benzoquinone (DBBQ) was applied to determine acid values of fats and oils, titrable acidity of coffee, and enzyme activity of lipase, free fatty acids (FFAs) in serum, short-chain fatty acids in feces, etc. The electrode reactions of phenothiazines, catechins, and cholesterol were applied to biomedical analysis using HPLC with electrochemical detection. A three-channel electrochemical detection system was utilized for the sensitive determination of redox compounds in Chinese herbal medicines. The behavior of barbituric acid derivatives was examined based on potential oscillation measurements.

  3. Inorganic nanolayers: structure, preparation, and biomedical applications

    Directory of Open Access Journals (Sweden)

    Saifullah B

    2015-09-01

    Full Text Available Bullo Saifullah, Mohd Zobir B HusseinMaterials Synthesis and Characterization Laboratory, Institute of Advanced Technology (ITMA, Universiti Putra Malaysia, Serdang, MalaysiaAbstract: Hydrotalcite-like compounds are two-dimensional inorganic nanolayers also known as clay minerals or anionic clays or layered double hydroxides/layered hydroxy salts, and have emerged as a single type of material with numerous biomedical applications, such as drug delivery, gene delivery, cosmetics, and biosensing. Inorganic nanolayers are promising materials due to their fascinating properties, such as ease of preparation, ability to intercalate different type of anions (inorganic, organic, biomolecules, and even genes, high thermal stability, delivery of intercalated anions in a sustained manner, high biocompatibility, and easy biodegradation. Inorganic nanolayers have been the focus for researchers over the last decade, resulting in widening application horizons, especially in the field of biomedical science. These nanolayers have been widely applied in drug and gene delivery. They have also been applied in biosensing technology, and most recently in bioimaging science. The suitability of inorganic nanolayers for application in drug delivery, gene delivery, biosensing technology, and bioimaging science makes them ideal materials to be applied for theranostic purposes. In this paper, we review the structure, methods of preparation, and latest advances made by inorganic nanolayers in such biomedical applications as drug delivery, gene delivery, biosensing, and bioimaging.Keywords: inorganic nanolayers, layered double hydroxides, layered hydroxy salts, drug delivery, biosensors, bioimaging

  4. Polymeric amines and biomedical uses thereof

    NARCIS (Netherlands)

    Broekhuis, Antonius; Zhang, Youchum; Picchioni, Francesco; Roks, Antonius

    2010-01-01

    The invention relates to the field of polymers and biomedical applications thereof. In particular, it relates to the use of polymeric amines derived from alternating polyketones.Provided is the use of a polymeric amine for modulating or supporting cellular behavior, said polymeric amine being an alt

  5. International Symposium on Biomedical Engineering and Medical Physics

    CERN Document Server

    Katashev, Alexei; Lancere, Linda

    2013-01-01

    This volume presents the proceedings of the International Symposium on Biomedical Engineering and Medical Physics and is dedicated to the 150 anniversary of the Riga Technical University, Latvia. The content includes various hot topics in biomedical engineering and medical physics.

  6. Elastomeric networks based on trimethylene carbonate polymers for biomedical applications : physical properties and degradation behaviour

    NARCIS (Netherlands)

    Bat, Erhan

    2010-01-01

    The number of applications for biomedical technologies is ever-increasing, and there is a need to develop new materials with properties that can conform to the requirements of a specific application. Synthetic polymers are of great importance in the biomedical field as they can be designed to exhibi

  7. Calculation of the shrinkage-induced residual stress in a viscoelastic dental restorative material

    Science.gov (United States)

    Grassia, Luigi; D'Amore, Alberto

    2013-02-01

    A procedure able to describe the curing process of a particulate composite material used in a dental restoration is developed in the ANSYS environment. The material under concern is a multifunctional methacrylate-based composite for dental restoration, activated by visible light. The model accounts for the dependence of the viscoelastic functions on temperature and degree of cure. Three geometries have been considered in the analysis that are representative of three different classes of dental restoration and mainly differ by the C (constrained)-factor, (i.e. the bounded to unbounded surface ratio). It was found that the temperature could give a necrosis in the vicinity of the tooth nerve and that the average stress at the interface between the composite and the tooth scales exponentially with the C-factor. The residual stress at the dental restoration interface is also compared with the uniaxial tensile strength of twelve commercially available composite materials: it clearly appears that the level of residual stress may overcome the strength of the composite, especially at high C-factors.

  8. About Dental Amalgam Fillings

    Science.gov (United States)

    ... Medical Procedures Dental Devices Dental Amalgam About Dental Amalgam Fillings Share Tweet Linkedin Pin it More sharing ... I have my fillings removed? What is dental amalgam? Dental amalgam is a dental filling material used ...

  9. Dental coping strategies, general anxiety, and depression among adult patients with dental anxiety but with different dental-attendance patterns.

    Science.gov (United States)

    Bernson, Jenny M; Elfström, Magnus L; Hakeberg, Magnus

    2013-06-01

    The aim of the present study was to investigate dental coping strategies, general anxiety, and depression in relation to regularity of dental treatment among persons with either regular dental care or phobic avoidance, whilst controlling for sociodemographic factors. Psychometric questionnaires on dental anxiety, dental coping strategies, general anxiety, and depression were delivered to 263 adult patients with dental phobic avoidance behavior who were seeking help from a specialized dental fear clinic and to 141 adult patients with dental anxiety who were receiving regular dental care from various public dental clinics. The results showed that the levels of dental and general anxiety and of depression were significantly higher among irregular attendees compared with regular attendees. Irregular attendees admitted fewer adaptive coping strategies. Predictive of irregular dental care were gender, dental anxiety, general anxiety, and the nonuse of the coping strategy 'optimism'. This study further confirms earlier preliminary results that the use of optimistic thinking is predictive for regular dental attendance habits and that male gender is a risk factor for irregular attendance. Moreover, this study adds that a high level of general anxiety indicates a higher risk for irregular dental care.

  10. Initial dental needs and a projection of needed dental capacity in the Iowa Department of Corrections.

    Science.gov (United States)

    Ringgenberg, Wendy J

    2011-04-01

    The dental health data for the Iowa Department of Corrections (IDOC) inmate population were analyzed to better understand dental health issues experienced by inmates and IDOC's system for responding to those dental needs. Each inmate is given a dental health assessment upon admission to Iowa's prison system. These data were analyzed for frequency of dental health needs and frequency of dental health services. In addition, emergency dental health services were analyzed. The findings show that each inmate has approximately 7.6 dental codes, including the initial exam, dental services provided, and dental needs not yet addressed. When reviewing only dental needs (and not the initial exam), 32% (5,110) identified dental needs were completed and 66% (10,572) were not.

  11. Dental, Dental Hygiene, and Graduate Students' and Faculty Perspectives on Dental Hygienists' Professional Role and the Potential Contribution of a Peer Teaching Program.

    Science.gov (United States)

    McComas, Martha J; Inglehart, Marita R

    2016-09-01

    The changing role of dental hygienists deserves dental and dental hygiene educators' attention. The first aim of this survey study was to assess University of Michigan dental, dental hygiene, and graduate students' and faculty members' perceptions of dental hygienists' roles; their attitudes and behaviors related to clinical interactions between dental and dental hygiene students; and perceived benefits of engaging dental hygiene students as peer teachers for dental students. The second aim was to assess whether one group of dental students' experiences with dental hygiene student peer teaching affected their perceptions of the dental hygiene profession. Survey respondents were 57 dental hygiene students in all three years of the program (response rate 60% to 100%); 476 dental students in all four years (response rate 56% to 100%); 28 dental and dental hygiene graduate students (response rate 28%); and 67 dental and dental hygiene faculty members (response rate 56%). Compared to the other groups, dental students reported the lowest average number of services dental hygienists can provide (p≤0.001) and the lowest average number of patient groups for which dental hygienists can provide periodontal care (phygiene and dental students (phygiene student peer teaching (phygiene student peer teaching, the dental students' perceptions of dental hygienists' roles, attitudes about clinical interactions with dental hygienists, and perceived benefits of dental hygiene student peer teachers improved and were more positive than the responses of their peers with no peer teaching experiences. These results suggest that dental hygiene student peer teaching may improve dental students' perceptions of dental hygienists' roles and attitudes about intraprofessional care.

  12. 不同种齿科修复材料与牙釉质磨损性能的临床评价%Different types of dental restoration materials and clinical evaluation of enamel wear performance

    Institute of Scientific and Technical Information of China (English)

    马福军; 王占红

    2011-01-01

    背景:冠修复体的严重磨耗会失去咬合功能甚至被磨穿,直接影响修复效果.目的:评价不同种类常用的牙齿修复材料与牙釉质之间的磨耗性能,寻求与天然牙釉质适应性较好的材料.方法:由第一作者检索1990-01/2010-02 PubMed数据及万方数据库有关牙齿修补材料及不同修复材料与牙釉质磨损性能关系的相关文献,英文检索词为"dental materials;composite resins; dental enamel;abrasive wear",中文检索词为"牙釉质;修复材料;磨损;烤瓷;纳米复合体".根据纳入标准,排除重复性研究,保留20篇文献进行分析.结果与结论:口腔是一个复杂的电解质环境,酸性饮食,茵斑堆积,细菌新陈代谢作用产生酸性物质,不论是无机酸还是有机酸,都会对金属的耐腐蚀性能产生不良影响.金属材料的化学稳定性好,耐腐蚀性强,与其表面形成的钝化膜有关,而非金属材料的耐腐蚀性则出现很大不同,参差不齐.磨耗性能牙科材料性能优良与否的主要因素,很多实验从牙科材料结构本身、牙齿磨损测量等多方面进行了深入研究,但对牙科材料的磨损机制研究还有待进一步深入.%BACKGROUND: Severe wear can lead to the loss of occlusal function or the crown restoration will be worn out, which directlyaffects the restoration results.OBJECTIVE: To evaluate the wear property between different types of dental restoration materials and dental enamel, and toseek a material adapting to natural enamel.METHODS: The first author retrieved PubMed database and Wanfang database from 1990 to 2010 for studies about dentalrepair materials and their wear relationships with dental enamel. English key words were “dental materials; composite resins;dental enamel; abrasive wear”, and Chinese key words were “enamel; repair materials; wear; porcelain; nanocomposite”. Therepetitive research was excluded. Twenty papers meeting the inclusion criteria were included in further

  13. Evaluating Stress Level Causes by Studying Environment and Related Factors in Dental Students of Yazd Dental College in 2014

    OpenAIRE

    Mirsaifi; Daneshkazemi; Sadeghian; Vosooghi

    2015-01-01

    Background Studying dentistry environment is important to assess stress causes, which is harmful for educational system. Objectives The present study was accomplished to evaluate the level of stress caused by studying environment and related factors in dental students of Yazd, IR Iran. Materials and Methods This was a cross-sectional study accomplished on 150 dental students. Data ...

  14. Dental Attitudes, Perceptions, and Treatment Needs in a University Population.

    Science.gov (United States)

    Cohen, Leonard A.; And Others

    1980-01-01

    Dental attitudes of college students were examined: frequency of past visits; subceptibility to dental conditions; seriousness, preventability, and treatability of dental conditions; and satisfaction with dentists, practices, and other dental conditions. (Authors/CJ)

  15. Chitin and chitosan based polyurethanes: A review of recent advances and prospective biomedical applications.

    Science.gov (United States)

    Usman, Ali; Zia, Khalid Mahmood; Zuber, Mohammad; Tabasum, Shazia; Rehman, Saima; Zia, Fatima

    2016-05-01

    Chitin and chitosan are amino polysaccharides having massive structural propensities to produce bioactive materials with innovative properties, functions and diverse applications particularly in biomedical field. The specific physico-chemical, mechanical, biological and degradation properties offer efficient way to blend these biopolymers with synthetic ones. Polyurethane (PU) gained substantial attention owing to its structure-properties relationship. The immense activities of chitin/chitosan are successfully utilized to enhance the bioactive properties of polyurethanes. This review shed a light on chitin and chitosan based PU materials with their potential applications especially focusing the bio-medical field. All the technical scientific issues have been addressed highlighting the recent advancement in the biomedical field.

  16. Synthesis and biomedical applications of aerogels: Possibilities and challenges.

    Science.gov (United States)

    Maleki, Hajar; Durães, Luisa; García-González, Carlos A; Del Gaudio, Pasquale; Portugal, António; Mahmoudi, Morteza

    2016-10-01

    Aerogels are an exceptional group of nanoporous materials with outstanding physicochemical properties. Due to their unique physical, chemical, and mechanical properties, aerogels are recognized as promising candidates for diverse applications including, thermal insulation, catalysis, environmental cleaning up, chemical sensors, acoustic transducers, energy storage devices, metal casting molds and water repellant coatings. Here, we have provided a comprehensive overview on the synthesis, processing and drying methods of the mostly investigated types of aerogels used in the biological and biomedical contexts, including silica aerogels, silica-polymer composites, polymeric and biopolymer aerogels. In addition, the very recent challenges on these aerogels with regard to their applicability in biomedical field as well as for personalized medicine applications are considered and explained in detail.

  17. Relationship between untreated dental caries and dental neglect among mentally handicapped children: A cross-sectional study

    Directory of Open Access Journals (Sweden)

    Amit Kumar

    2015-01-01

    Full Text Available Introduction: Dental caries is the most prevalent disease among mentally handicapped (MH children worldwide. Dental neglect may throw light on complex relationships between individual behavior, environmental factors, and dental caries in children. Objectives: The objective was to assess the prevalence and severity of untreated dental caries and to explore the relationship between untreated dental caries and dental neglect among MH children and healthy children in Bangalore city. Materials and Methods: A cross-sectional comparative study was conducted on 130, 6-17 years MH and 152 healthy school children in Bangalore city. A questionnaire on the children′s sociodemographic background, oral health-related behaviors, and dental neglect scale was completed by the parents. Caries was assessed according to World Health Organization criteria (1997. Odontogenic infections were recorded using the pufa/PUFA index. Statistical tests such as Mann-Whitney U-test, Chi-square test, Spearmans correlation, and step-wise linear regression were performed at significance level P < 0.05. Results: Dental caries was present in 89.2% of MH children as compared with 88.15% of the healthy children. Caries experience significantly correlated with consequences of untreated dental caries in both the groups (P = 0.001. No statistical significant correlation was observed between dental neglect and dental caries experience and its consequences in both the groups. Conclusions: High prevalence of dental caries and dental neglect in both the groups calls for an integrated approach. Oral health promotion and intervention programs should be targeted and concentrated toward these risk groups.

  18. Dental students' motivation and the context of learning.

    Science.gov (United States)

    Kristensen, Bettina Tjagvad; Netterstrom, Ingeborg; Kayser, Lars

    2009-02-01

    This qualitative study shows dental students' motives for choosing the dental education and how the motives influence their motivation at the first semester of study. Further the study demonstrates the relevance of the context of learning. This issue is of importance when planning a curriculum for the dental education. The material consists of interviews with eight dental students. The results show that dental students were focused on their future professional role, its practical dimensions and their future working conditions. Their motivation for choosing the dental education was found to influence their motivation for studying and their experience of the relevance of the first semester. The dental students who had co-education with the medical students at the first year of study missed a dental context and courses with clinically relevant contents. In conclusion, our data signify the importance of the context of learning. It is recommended that a future curriculum for the dental school should be designed in a way where basic science subjects are taught with both theoretically as well as practically oriented subjects and in a context which is meaningful for the students.

  19. Association between Childhood Dental Experiences and Dental Fear among Dental, Psychology and Mathematics Undergraduates in Brazil

    Directory of Open Access Journals (Sweden)

    Júnia M. Serra-Negra

    2012-12-01

    Full Text Available The aim of the present study was to evaluate the association between childhood dental experiences and dental fear in adulthood among dentistry, psychology and mathematics undergraduate students. A cross-sectional study of 1,256 students from the city of Belo Horizonte, Brazil, was performed. Students responded to the Brazilian version of the Dental Fear Survey (DFS and a questionnaire regarding previous dental experiences. Both the DFS and the questionnaire were self-administered. Association was tested using descriptive, bivariate and multivariate linear regression analysis, with a 5% significance level. Dentistry undergraduates reported lower scores than psychology (p < 0.001 and mathematics undergraduates (p < 0.05 for all three dimensions of the DFS. Negative dental experiences in childhood was associated with dimensions of Avoidance (B = 2.70, p < 0.001, Physiological arousal (B = 1.42, p < 0.001 and Fears of specific stimuli/situations (B = 3.44, p < 0.001. The reason for first visit to dentist was associated with dimensions of Physiological arousal (B = 0.76, p < 0.01 and Fears of specific stimuli/situations (B = 1.29, p < 0.01. Dentists should be encouraged to evaluate the dental fear of their patients before treatment. The DFS has been found to be an effective instrument for this purpose.

  20. Mining biomedical images towards valuable information retrieval in biomedical and life sciences.

    Science.gov (United States)

    Ahmed, Zeeshan; Zeeshan, Saman; Dandekar, Thomas

    2016-01-01

    Biomedical images are helpful sources for the scientists and practitioners in drawing significant hypotheses, exemplifying approaches and describing experimental results in published biomedical literature. In last decades, there has been an enormous increase in the amount of heterogeneous biomedical image production and publication, which results in a need for bioimaging platforms for feature extraction and analysis of text and content in biomedical images to take advantage in implementing effective information retrieval systems. In this review, we summarize technologies related to data mining of figures. We describe and compare the potential of different approaches in terms of their developmental aspects, used methodologies, produced results, achieved accuracies and limitations. Our comparative conclusions include current challenges for bioimaging software with selective image mining, embedded text extraction and processing of complex natural language queries.

  1. Medical and biomedical applications of shock waves

    CERN Document Server

    Loske, Achim M

    2017-01-01

    This book provides current, comprehensive, and clear explanations of the physics behind medical and biomedical applications of shock waves. Extracorporeal shock wave lithotripsy is one of the greatest medical advances of our time, and its techniques and clinical devices are continuously evolving. Further research continues to improve the understanding of calculi fragmentation and tissue-damaging mechanisms. Shock waves are also used in orthopedics and traumatology. Possible applications in oncology, cardiology, dentistry, gene therapy, cell transfection, transformation of fungi and bacteria, as well as the inactivation of microorganisms are promising approaches for clinical treatment, industrial applications and research. Medical and Biomedical Applications of Shock Waves is useful as a guide for students, technicians and researchers working in universities and laboratories. Chemists, biologists, physicians and veterinarians, involved in research or clinical practice will find useful advice, but also engineer...

  2. Anodization of Ti-based materials for biomedical applications: A review

    Directory of Open Access Journals (Sweden)

    Dragana R. Barjaktarević

    2016-09-01

    Full Text Available Commercially pure titanium (cpTi and titanium alloys are the most commonly used metallic biomaterials. Biomedical requirements for the successful usage of metallic implant materials include their high mechanical strength, low elastic modulus, excellent biocompatibility and high corrosion resistance. It is evident that the response of a biomaterial implanted into the human body depends entirely on its biocompatibility and surface properties. Therefore, in order to improve the performance of biomaterials in biological systems modification of their surface is necessary. One of most commonly used method of implant materials surface modification is electrochemical anodization and this method is reviewed in the present work.Aim of the presented review article is to explain the electrochemical anodization process and the way in which the nanotubes are formed by anodization on the metallic material surface. Influence of anodizing parameters on the nanotubes characteristics, such as nanotube diameter, length and nanotubular layer thickness, are described, as well as the anodized nanotubes influence on the material surface properties, corrosion resistance and biocompatibility.

  3. A Review on Dental Amalgam Corrosion and Its Consequences

    Directory of Open Access Journals (Sweden)

    M Fathi

    2004-02-01

    Full Text Available Dental amalgam is still the most useful restorative material for posterior teeth and has been successfully used for over a century. Dental amalgam has been widely used as a direct filling material due to its favorable mechanical properties as well as low cost and easy placement. However, the mercury it contains raises concerns about its biological toxicity and environmental hazard. Although in use for more than 150 years, dental amalgam has always been suspected more or less vigorously due to its alleged health hazard. Amalgam restorations often tarnish and corrode in oral environment. Corrosion of dental amalgam can cause galvanic action. Ion release as a result of corrosion is most important. Humans are exposed to mercury and other main dental metals via vapor or corrosion products in swallowed saliva and also direct absorption into blood from oral mucosa. During recent decades the use of dental amalgam has been discussed with respect to potential toxic effects of mercury components. In this article, the mechanisms of dental amalgam corrosion are described and results of researches are reviewed. It finally covers the corrosion of amalgams since this is the means by which metals, including mercury, can be released within oral cavity. Keywords: Dental amalgam, Amalgam corrosion, Biocompatibility, Mercury release, Amalgam restoration

  4. Stress and morale of academic biomedical scientists.

    Science.gov (United States)

    Holleman, Warren L; Cofta-Woerpel, Ludmila M; Gritz, Ellen R

    2015-05-01

    Extensive research has shown high rates of burnout among physicians, including those who work in academic health centers. Little is known, however, about stress, burnout, and morale of academic biomedical scientists. The authors interviewed department chairs at one U.S. institution and were told that morale has plummeted in the past five years. Chairs identified three major sources of stress: fear of not maintaining sufficient funding to keep their positions and sustain a career; frustration over the amount of time spent doing paperwork and administrative duties; and distrust due to an increasingly adversarial relationship with the executive leadership.In this Commentary, the authors explore whether declining morale and concerns about funding, bureaucracy, and faculty-administration conflict are part of a larger national pattern. The authors also suggest ways that the federal government, research sponsors, and academic institutions can address these concerns and thereby reduce stress and burnout, increase productivity, and improve overall morale of academic biomedical scientists.

  5. Implantable biomedical microsystems design principles and applications

    CERN Document Server

    Bhunia, Swarup; Sawan, Mohamad

    2015-01-01

    Research and innovation in areas such as circuits, microsystems, packaging, biocompatibility, miniaturization, power supplies, remote control, reliability, and lifespan are leading to a rapid increase in the range of devices and corresponding applications in the field of wearable and implantable biomedical microsystems, which are used for monitoring, diagnosing, and controlling the health conditions of the human body. This book provides comprehensive coverage of the fundamental design principles and validation for implantable microsystems, as well as several major application areas. Each co

  6. The Effect of Surface Properties of Biomedical Materials on Their Blood Compatibility

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The effect of surface properties of six types of biomedical materials on their blood compatibility was investigated in this study. The surface roughness of biomaterials was determined by confocal laser scanning microscopy (CLSM). The contact angle was observed by contact angle measurement (CAM). Then the surface free energy ( SFE ) and interfacial free energy ( IFE ) were calculated by the contact angle value based on the Owens-Wendt (OW) theoretical model and Young's equation. Meanwhile, hemolytic assay was employed to evaluate the haemolysis. The experimental results showed that the greater roughness was, the greater contact angle would be; the less proportion of polar component in surface free energy (SFE) was, the lower haemolysis would be.

  7. Effects of Different pH-Values on the Nanomechanical Surface Properties of PEEK and CFR-PEEK Compared to Dental Resin-Based Materials

    Directory of Open Access Journals (Sweden)

    Shuai Gao

    2015-07-01

    Full Text Available The study determines the stability and durability of polyetheretherketone (PEEK and a carbon fiber-reinforced PEEK (CFR-PEEK with 30% short carbon fibers, a dental composite based on Bis-GMA and polymethylmethacrylate (PMMA under the influence of different pH-values of the oral environment in vitro. Nanomechanical properties were investigated by nanoindentation and nanoscratch tests before and after incubation of the specimens at 37 °C for 30 days in artificial saliva with pH-values of 3, 7 and 10, respectively. Nanoindentation and nanoscratching tests were performed using the Hysitron TI950 TriboIndenter to evaluate the reduced elastic moduli, nanohardness, viscoelasticity, friction coefficient and residual scratch profiles. After treatment, the nanomechanical properties of unfilled PEEK did not change. The reduced elastic moduli and nanohardness of the carbon fiber-reinforced PEEK increased significantly. The reduced elastic moduli and nanohardness of CHARISMA decreased. The plasticity of all materials except that of the unfilled PEEK increased. This indicates that different pH-values of the artificial saliva solutions had no obvious influences on the nanomechanical properties of the PEEK matrix. Therefore, the aging resistance of the unfilled PEEK was higher than those of other materials. It can be deduced that the PEEK matrix without filler was more stable than with filler in the nanoscale.

  8. Biomedical Device Technology Principles and Design

    CERN Document Server

    Chan, Anthony Y K

    2008-01-01

    For many years, the tools available to physicians were limited to a few simple handpieces such as stethoscopes, thermometers and syringes; medical professionals primarily relied on their senses and skills to perform diagnosis and disease mitigation. Today, diagnosis of medical problems is heavily dependent on the analysis of information made available by sophisticated medical machineries such as electrocardiographs, ultrasound scanners and laboratory analyzers. Patient treatments often involve specialized equipment such as cardiac pacemakers and electrosurgical units. Such biomedical instrumen

  9. Biomedical engineering frontier research and converging technologies

    CERN Document Server

    Jun, Ho-Wook; Shin, Jennifer; Lee, SangHoon

    2016-01-01

    This book provides readers with an integrative overview of the latest research and developments in the broad field of biomedical engineering. Each of the chapters offers a timely review written by leading biomedical engineers and aims at showing how the convergence of scientific and engineering fields with medicine has created a new basis for practically solving problems concerning human health, wellbeing and disease. While some of the latest frontiers of biomedicine, such as neuroscience and regenerative medicine, are becoming increasingly dependent on new ideas and tools from other disciplines, the paradigm shift caused by technological innovations in the fields of information science, nanotechnology, and robotics is opening new opportunities in healthcare, besides dramatically changing the ways we actually practice science. At the same time, a new generation of engineers, fluent in many different scientific “languages,” is creating entirely new fields of research that approach the “old” questions f...

  10. Advanced silk material spun by a transgenic silkworm promotes cell proliferation for biomedical application.

    Science.gov (United States)

    Wang, Feng; Xu, Hanfu; Wang, Yuancheng; Wang, Riyuan; Yuan, Lin; Ding, Huan; Song, Chunnuan; Ma, Sanyuan; Peng, Zhixin; Peng, Zhangchuan; Zhao, Ping; Xia, Qingyou

    2014-12-01

    Natural silk fiber spun by the silkworm Bombyx mori is widely used not only for textile materials, but also for biofunctional materials. In the present study, we genetically engineered an advanced silk material, named hSFSV, using a transgenic silkworm, in which the recombinant human acidic fibroblast growth factor (hFGF1) protein was specifically synthesized in the middle silk gland and secreted into the sericin layer to surround the silk fiber using our previously optimized sericin1 expression system. The content of the recombinant hFGF1 in the hSFSV silk was estimated to be approximate 0.07% of the cocoon shell weight. The mechanical properties of hSFSV raw silk fiber were enhanced slightly compared to those of the wild-type raw silk fiber, probably due to the presence of the recombinant of hFGF1 in the sericin layer. Remarkably, the hSFSV raw silk significantly stimulated the cell growth and proliferation of NIH/3T3 mouse embryonic fibroblast cells, suggesting that the mitogenic activity of recombinant hFGF1 was well maintained and functioned in the sericin layer of hSFSV raw silk. These results show that the genetically engineered raw silk hSFSV could be used directly as a fine biomedical material for mass application. In addition, the strategy whereby functional recombinant proteins are expressed in the sericin layer of silk might be used to create more genetically engineered silks with various biofunctions and applications.

  11. Dried fruit and dental health.

    Science.gov (United States)

    Sadler, Michèle Jeanne

    2016-12-01

    A comprehensive review of the literature has found that the common perceptions that dried fruits are "sticky", adhere to teeth, and are detrimental to dental health on account of their sugar content are based on weak evidence. There is a lack of good quality scientific data to support restrictive advice for dried fruit intake on the basis of dental health parameters and further research is required. A number of potentially positive attributes for dental health, such as the need to chew dried fruits which encourages salivary flow, and the presence of anti-microbial compounds and of sorbitol, also require investigation to establish the extent of their effects and whether they balance against any potentially negative attributes of dried fruit. Advice on dried fruit consumption should also take account of the nutritional benefits of dried fruit, being high in fibre, low in fat and containing useful levels of micronutrients.

  12. Production and Biomedical Applications of Probiotic Biosurfactants.

    Science.gov (United States)

    Fariq, Anila; Saeed, Ayesha

    2016-04-01

    Biosurfactants have been widely used for environmental and industrial applications. However, their use in medical field is still limited. Probiotic biosurfactants possess an immense antimicrobial, anti-adhesive, antitumor, and antibiofilm potential. Moreover, they have an additional advantage over conventional microbial surfactants because probiotics are an integral part of normal human microflora and their biosurfactants are innocuous to human. So, they can be effectively exploited for medicinal use. Present review is aimed to discourse the production and biomedical applications of probiotic biosurfactants.

  13. Cyanine polyene reactivity: scope and biomedical applications.

    Science.gov (United States)

    Gorka, Alexander P; Nani, Roger R; Schnermann, Martin J

    2015-07-28

    Cyanines are indispensable fluorophores that form the chemical basis of many fluorescence-based applications. A feature that distinguishes cyanines from other common fluorophores is an exposed polyene linker that is both crucial to absorption and emission and subject to covalent reactions that dramatically alter these optical properties. Over the past decade, reactions involving the cyanine polyene have been used as foundational elements for a range of biomedical techniques. These include the optical sensing of biological analytes, super-resolution imaging, and near-IR light-initiated uncaging. This review surveys the chemical reactivity of the cyanine polyene and the biomedical methods enabled by these reactions. The overarching goal is to highlight the multifaceted nature of cyanine chemistry and biology, as well as to point out the key role of reactivity-based insights in this promising area.

  14. Morphological Study Of Border Area Of Pulp-Capping Materials And Er:YAG Laser Prepared Hard Dental Surface

    Directory of Open Access Journals (Sweden)

    Stefanova Vessela P.

    2015-03-01

    Full Text Available Introduction: Vital pulp therapy involves biologically based therapeutic activities aimed at restoring health and preserving the vitality of cariously or traumatically damaged pulp. Adaptation of pulp-capping materials to the prepared tooth surface may be the key to the success of biological tooth treatment.

  15. Biomedical Applications of NASA Science and Technology

    Science.gov (United States)

    Brown, James N., Jr.

    1968-01-01

    During the period 15 September 1968 to 14 December 1968, the NASA supported Biomedical Application Team at the Research Triangle Institute has identified 6 new problems, performed significant activities on 15 of the active problems identified previously, performed 5 computer searches of the NASA aerospace literature, and maintained one current awareness search. As a partial result of these activities, one technology transfer was accomplished. As a part of continuing problem review, 13 problems were classified inactive. Activities during the quarter involved all phases of team activity with respect to biomedical problems. As has been observed in preceding years, it has been exceedingly difficult to arrange meetings with medical investigators during the fourth quarter of the calendar year. This is a result of a combination of factors. Teaching requirements, submission of grant applications and holidays are the most significant factors involved. As a result, the numbers of new problems identified and of transfers and potential transfers are relatively low during this quarter. Most of our activities have thus been directed toward obtaining information related to problems already identified. Consequently, during the next quarter we will follow up on these activities with the expectation that transfers will be accomplished on a number of them. In addition, the normal availability of researchers to the team is expected to be restored during this quarter, permitting an increase in new problem identification activities as well as follow-up with other researchers on old problems. Another activity scheduled for the next quarter is consultation with several interested biomedical equipment manufacturers to explore means of effective interaction between the Biomedical Application Team and these companies.

  16. Biocompatibility of dental materials used in contemporary endodontic therapy: a review. Part 1. Intracanal drugs and substances.

    Science.gov (United States)

    Hauman, C H J; Love, R M

    2003-02-01

    Irrigation solutions and intracanal medicaments are used within the root canal to clean and aid in disinfecting the dentinal walls. Although these materials are intended to be contained within the root canal, they invariably contact the periapical tissues, either through inadvertent extrusion through the apex or leaching. This paper is a review on the methodology involved in biocompatibility testing followed by a discussion on biocompatibility of contemporary intracanal drugs and substances used in endodontics.

  17. Strand I - Physical Health; Dental Health for Grades K-3. Special Edition for Evaluation and Discussion.

    Science.gov (United States)

    New York State Education Dept., Albany. Curriculum Development Center.

    This is a curriculum guide for teaching dental health material to early elementary grade students. This outline emphasizes the prevention and treatment of dental diseases, and is designed to provide the knowledge and develop the habits necessary for a lifetime of good dental health. A list of seven pupil objectives is presented to develop good…

  18. The biomedical disciplines and the structure of biomedical and clinical knowledge.

    Science.gov (United States)

    Nederbragt, H

    2000-11-01

    The relation between biomedical knowledge and clinical knowledge is discussed by comparing their respective structures. The knowledge of a disease as a biological phenomenon is constructed by the interaction of facts and theories from the main biomedical disciplines: epidemiology, diagnostics, clinical trial, therapy development and pathogenesis. Although these facts and theories are based on probabilities and extrapolations, the interaction provides a reliable and coherent structure, comparable to a Kuhnian paradigma. In the structure of clinical knowledge, i.e. knowledge of the patient with the disease, not only biomedical knowledge contributes to the structure but also economic and social relations, ethics and personal experience. However, the interaction between each of the participating "knowledges" in clinical knowledge is not based on mutual dependency and accumulation of different arguments from each, as in biomedical knowledge, but on competition and partial exclusion. Therefore, the structure of biomedical knowledge is different from that of clinical knowledge. This difference is used as the basis for a discussion in which the place of technology, evidence-based medicine and the gap between scientific and clinical knowledge are evaluated.

  19. Facial and Dental Injuries Facial and Dental Injuries in Karate.

    Science.gov (United States)

    Vidovic-Stesevic, Vesna; Verna, Carlalberta; Krastl, Gabriel; Kuhl, Sebastian; Filippi, Andreas

    2015-01-01

    Karate is a martial art that carries a high trauma risk. Trauma-related Swiss and European karate data are currently unavailable. This survey seeks to increase knowledge of the incidence of traumatic facial and dental injuries, their emergency management, awareness of tooth rescue boxes, the use of mouthguards and their modifications. Interviews were conducted with 420 karate fighters from 43 European countries using a standardized questionnaire. All the participants were semi-professionals. The data were evaluated with respect to gender, kumite level (where a karate practitioner trains against an adversary), and country. Of the 420 fighters interviewed, 213 had experienced facial trauma and 44 had already had dental trauma. A total of 192 athletes had hurt their opponent by inflicting a facial or dental injury, and 290 knew about the possibility of tooth replantation following an avulsion. Only 50 interviewees knew about tooth rescue boxes. Nearly all the individuals interviewed wore a mouthguard (n = 412), and 178 of them had made their own modifications to the guard. The results of the present survey suggest that more information and education in wearing protective gear are required to reduce the incidence of dental injuries in karate.

  20. Bisphenol A in dental sealants and its estrogen like effect

    Directory of Open Access Journals (Sweden)

    Manu Rathee

    2012-01-01

    Full Text Available Bisphenol A or BPA-based epoxy resins are widely used in the manufacture of commercial products, including dental resins, polycarbonate plastics, and the inner coating of food cans. BPA is a precursor to the resin monomer Bis-GMA. During the manufacturing process of Bis-GMA dental sealants, Bisphenol A (BPA might be present as an impurity or as a degradation product of Bis-DMA through esterases present in saliva. Leaching of these monomers from resins can occur during the initial setting period and in conjunction with fluid sorption and desorption over time and this chemical leach from dental sealants may be bioactive. Researchers found an estrogenic effect with BPA, Bis-DMA, and Bis-GMA because BPA lacks structural specificity as a natural ligand to the estrogen receptor. It generated considerable concern regarding the safety of dental resin materials. This review focuses on the BPA in dental sealants and its estrogen-like effect.

  1. Nutrition and Experimental Dental Caries

    OpenAIRE

    田村,俊吉; タムラ, シュンキチ; Shunkichi, TAMURA

    1983-01-01

    Nutrition is an effective factor for the inhibition of the development of dental caries. The constitution of diet has a strong bearing on the development of dental caries. However the theoretical background regarding the development of dental caries has not been sastifactorily established. Experimentally, we have clarified the relation of nutrition and dental caries in rats. Experimental animals used in this study were Wistar strain Albino rats (closed colony, Tamura, 1950). Young rats of 21 ...

  2. Anxiety and pain during dental injections

    NARCIS (Netherlands)

    A.J. van Wijk; J. Hoogstraten

    2009-01-01

    Objectives: The aim of this study was to study the relationship between anxiety and pain felt during a dental injection in a sample of ‘normal’ patients about to undergo ‘invasive’ dental treatment. Methods: Duration and intensity of pain during a dental injection were measured within a sample of 24

  3. Effect of the disinfection technique on the linear dimensional stability of dental impression materials

    OpenAIRE

    Silva, Sávio Marcelo Leite Moreira da; Salvador, Milton Carlos Gonçalves

    2004-01-01

    The purpose of this study was to evaluate the dimensional stability of heavy and light bodied condensation silicones after immersion in disinfectant solution for 10 or 20 minutes. The impression materials were Optosil Comfort and Xantopren VL Plus and the disinfectant solutions were 1% sodium hypochlorite and 2% glutaraldehyde. Impressions were made on a perforated stainless steel tray, according to the American Dental Association specification No. 19, adding up to a total of 50 samples. The ...

  4. Anti-fouling Coatings of Poly(dimethylsiloxane) Devices for Biological and Biomedical Applications

    OpenAIRE

    Zhang, Hongbin; Chiao, Mu

    2015-01-01

    Fouling initiated by nonspecific protein adsorption is a great challenge in biomedical applications, including biosensors, bioanalytical devices, and implants. Poly(dimethylsiloxane) (PDMS), a popular material with many attractive properties for device fabrication in the biomedical field, suffers serious fouling problems from protein adsorption due to its hydrophobic nature, which limits the practical use of PDMS-based devices. Effort has been made to develop biocompatible materials for anti-...

  5. Prevalence and distribution of selected dental anomalies among saudi children in Abha, Saudi Arabia

    OpenAIRE

    Yassin, Syed M.

    2016-01-01

    Background Dental anomalies are not an unusual finding in routine dental examination. The effect of dental anomalies can lead to functional, esthetic and occlusal problems. The Purpose of the study was to determine the prevalence and distribution of selected developmental dental anomalies in Saudi children. Material and Methods The study was based on clinical examination and Panoramic radiographs of children who visited the Pediatric dentistry clinics at King Khalid University College of Dent...

  6. 生物医用材料与3D打印技术的完美结合%The Binding of Bio-medical Materials and 3D Printing

    Institute of Scientific and Technical Information of China (English)

    陈贤明; 陆国英

    2015-01-01

    Bio-medical materials have been consider for implants or in combination with biological tissue with no bad influence. As a typical example of smart manufacturing,3D printing is a method of manufacturing in which materials, such as plastic or metal, are deposited onto one another in layers to produce a three dimensional object, such as a pair of eye glasses or other 3D objects. 3D priting can been used to print out quickly and accurately for different bio-medical materials. Therefore, for further explore its application in the bio-medical ifeld, 3D priting technology wil be more widly applied and developed.%生物医用材料指的是用于医疗上能够植入生物体或与生物组织相结合,而对生物体组织不会产生不良影响的材料。3D打印技术,即快速成型技术的一种,它是一种以数字模型文件为基础,配合机械制造和材料科学,使材料在液态或是气态时直接固化成所需结构。临床医学研究人员可根据不同患者的需求,采用3D打印技术快速精确打印出适合不同患者的个性化生物医用生物材料,同时,还可以对材料的微观结构进行精确控制。因此,这种新兴生物医用材料的研制结合3D打印技术,在未来生物医学领域将会得到更广泛的应用和发展。

  7. Quantification of Staphylococcus aureus adhesion forces on various dental restorative materials using atomic force microscopy

    Science.gov (United States)

    Merghni, Abderrahmen; Kammoun, Dorra; Hentati, Hajer; Janel, Sébastien; Popoff, Michka; Lafont, Frank; Aouni, Mahjoub; Mastouri, Maha

    2016-08-01

    In the oral cavity dental restorative biomaterials can act as a reservoir for infection with opportunistic Staphylococcus aureus pathogen, which can lead to the occurrence of secondary caries and treatment failures. Our aim was to evaluate the adhesion forces by S. aureus on four dental restorative biomaterials and to correlate this finding to differences in specific surface characteristics. Additionally, the influence of salivary conditioning films in exerted adhesion forces was investigated. The substrate hydrophobicity was measured by goniometer and the surface free energy was calculated using the equilibrium advancing contact angle values of water, formamide, and diiodomethane on the tested surfaces. The surface roughness was determined using atomic force microscope (AFM). Additionally, cell force spectroscopy was achieved to quantify the forces that drive cell-substrate interactions. S. aureus bacterium exerted a considerable adhesion forces on various dental restorative materials, which decreased in the presence of saliva conditioning film. The influence of the surface roughness and free energy in initial adhesion appears to be more important than the effect of hydrophobicity, either in presence or absence of saliva coating. Hence, control of surface properties of dental restorative biomaterials is of crucial importance in preventing the attachment and subsequent the biofilm formation.

  8. Methods of improving mechanical and biomedical properties of Ca-Si-based ceramics and scaffolds.

    Science.gov (United States)

    Wu, Chengtie

    2009-05-01

    CaSiO3 ceramics and porous scaffolds are regarded as potential materials for bone tissue regeneration owing to their excellent bioactivity. However, their low mechanical strength and high dissolution limit their further biomedical application. In this report, we introduce three methods to improve the mechanical and biomedical properties of CaSiO3 ceramics and scaffolds. Positive ions and polymer modification are two promising ways to improve the mechanical and biomedical properties of CaSiO3 ceramics and scaffolds for bone tissue regeneration.

  9. Experiences of Dental Care and Dental Anxiety in Adults with Autism Spectrum Disorder

    Directory of Open Access Journals (Sweden)

    My Blomqvist

    2014-01-01

    Full Text Available Dental anxiety is associated with previous distressing dental experiences, such as lack of understanding of the dentist intentions, perceptions of uncontrollability and experiences of pain during dental treatment. People with autism spectrum disorder (ASD are impaired in building flexible predictions and expectations, which is very much needed during a dental visit. The aims of the study were to investigate if people with ASD have more negative dental experiences and a higher level of dental anxiety compared to a matched control group. Forty-seven adults with ASD and of normal intellectual performance, and 69 age- and sex-matched typically developing controls completed questionnaires on previous dental experiences and dental anxiety, the Dental Anxiety Scale, and the Dental Beliefs Survey. The ASD group experienced pain during dental treatments more often than the controls and 22% had repeatedly experienced being forced to dental treatment they were not prepared for, compared to 3% of the controls. A higher level of dental anxiety was reported by the ASD group. Dental treatment and methods for supporting the communication with patients with ASD need to be developed, in order to reduce the negative dental experiences and dental anxiety in people with ASD.

  10. Prevention and dental health services.

    Science.gov (United States)

    Widström, Eeva

    2004-01-01

    There has been, and still is a firm belief that regular use of dental services is beneficial for all. Thus governments in most European countries have shown some interest in training oral health care professionals, distributing the dental workforce and cost sharing. Constantly evolving treatment options and the introduction of new methods make dental clinicians feel uncertain as to which treatments are most useful, who would benefit from them, and which treatments will achieve cost-effective health gain. Although there is a considerable quantity of scientific literature showing that most available preventive measures are effective, and the number of sensible best-practice guidelines in prevention is growing, there are few studies on cost-efficiency of different methods and, secondly, the prevention and treatment guidelines are poorly known among general practitioners. In the eyes of the public, it is obvious that preventive methods practised by patients at home have been eclipsed by clinical procedures performed in dental clinics. Reliance on an increasingly individualistic approach to health care leads to the medicalisation of issues that are not originally health or medical problems. It is important to move general oral disease prevention back to the people who must integrate this in their daily routines. Prevention primarily based on healthy lifestyles, highlighted in the new public health strategy of the European Union (EU), is the key to future health policy.

  11. Biomedical Effects and Nanomaterials: Nanosafety of Engineered Recent Progress%Biomedical Effects and Nanomaterials: Nanosafety of Engineered Recent Progress

    Institute of Scientific and Technical Information of China (English)

    王晓峰; 朱墨桃; 李敬源

    2012-01-01

    With the development of nanotechnology, there are growing concerns about biological effects and biosafety of engineered nanomaterials. On the other hand, nanoparticles are widely used in medical fields based on their novel interactions with biological entities. However, there are still a lot of challenges to establish systematic knowledge about nanotoxicology and develop biologically safer biomedical materials due to the variety of factors determining their biomedical effects and nanotoxicity. Understanding the interactions of engineered nanomaterials with the bio- logical entities becomes crucial to the further development of nanoscience and nanotechnology. In the past decade, colleagues in our laboratory intensively studied the toxic properties of various kinds of nanomaterials and their chemical mechanisms. In this paper we review the recent advance in the research on the biological effects of engi- neered nanomaterials and nanosafety issue, by focusing on the studies about representative nanomaterials in our la- boratory.

  12. Signal and image analysis for biomedical and life sciences

    CERN Document Server

    Sun, Changming; Pham, Tuan D; Vallotton, Pascal; Wang, Dadong

    2014-01-01

    With an emphasis on applications of computational models for solving modern challenging problems in biomedical and life sciences, this book aims to bring collections of articles from biologists, medical/biomedical and health science researchers together with computational scientists to focus on problems at the frontier of biomedical and life sciences. The goals of this book are to build interactions of scientists across several disciplines and to help industrial users apply advanced computational techniques for solving practical biomedical and life science problems. This book is for users in t

  13. An in vitro study of dental enamel wear by restorative materials using radiometric method; Estudo in vitro do desgaste do esmalte dental pelos materiais restauradores utilizando metodo radiometrico

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Lena Katekawa

    2000-07-01

    There is an increasing demand and interest to study the dental materials wear as well as about the abrasion effect on antagonistic teeth. Due to the fact that the existent restorative materials have no specifications about their abrasiveness, it is necessary the establishment of degrees of comparison among them to support clinical application. In this work, the radiometric method was applied to study the enamel wear caused by another enamel and by restorative materials (Ceramco II, Noritake and Finesse porcelains, Artglass and Targis). The dental enamel made radioactive by irradiation at the IEA-R1m nuclear research reactor under a thermal neutron flux was submitted to wear in a machine which allows sliding motion of an antagonistic surface in contact with this radioactive enamel. The enamel wear was evaluated by measuring beta activity of {sup 32}P transferred to water from this irradiated tooth. Results obtained indicated that dental porcelains cause pronounced enamel wear when compared with that provoked by another enamel or by resin materials. Resin materials caused less enamel wear than another enamel. Vickers microhardness data obtained for antagonistic materials showed a correlation with the wear caused to the enamel. This study allowed to conclude that the radiometric method proposed can be used satisfactorily in the evaluation of enamel wear by restorative materials. This method presents advantages due to quick responses and ease of analyses There is (author)

  14. Aptamers: Biomedical Interest and Applications

    Directory of Open Access Journals (Sweden)

    Cristina Romero-López

    2017-03-01

    Full Text Available Aptamers are short DNA or RNA oligonucleotides specialized in the specific and efficient binding to a target molecule. They are obtained by in vitro selection or evolution processes. It was in 1990 that two independent research groups described the bases of a new in vitro technology for the identification of RNA molecules able to specifically bind to a target [1,2]. Tuerk and Gold established the principals of the in vitro selection process that was named SELEX (Systematic Evolution of Ligands by Exponential enrichment, which is based on iterative cycles of binding, partitioning, and amplification of oligonucleotides from a pool of variant sequences [2]. Ellington and Szostak coined the term aptamer to define the selected molecules by the application of this method [1]. To date, numerous reports have described the isolation of aptamers directed against a great variety of targets covering a wide diversity of molecules varying in nature, size, and complexity ranging from ions to whole cells, including small molecules (e.g., aminoacids, nucleotides, antibiotics, peptides, proteins, nucleic acids, and viruses, among others (for example, see [3–6]. Modifications and optimization of the SELEX procedure aimed to get newly modified aptamers has also attracted much interest (examples can be found in [7,8]. These advances along with the parallel progresses in the nucleic acids chemistry and cellular delivery fields have allowed for the rise of a new hope in developing aptamers as efficient molecular tools for diagnostics and therapeutics (for recent comprehensive reviews, see [9–11].

  15. Biomedical engineering and rehabilitation techniques

    Energy Technology Data Exchange (ETDEWEB)

    Gaussens, G.; Jouve, B.; Laizier, J. (Office des Rayonnements Ionisants, CEN Saclay (France))

    The authors outline the programmes set up by the ORIS for the development of biomaterials and rehabilitation products using the radiochemical techniques. They then discuss the development of instruments designed to make the handling and use of radioactive isotopes easier for users.

  16. Synchrotron radiation and biomedical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Luccio, A.

    1986-08-01

    In this lecture we describe the characteristics of Synchrotron radiation as a source of X rays. We discuss the properties of SR arc sources, wigglers, undulators and the use of backscattering of laser light. Applications to angiography, X ray microscopy and tomography are reviewed. 16 refs., 23 figs.

  17. Disinfection of dental impressions and occlusal records by ultraviolet radiation.

    Science.gov (United States)

    Larsen, T; Fiehn, N E; Peutzfeldt, A; Owall, B

    2000-06-01

    As chemical disinfection of dental impressions may cause adverse effects on materials and the dental personnel this study examined disinfection by ultraviolet radiation. Alginate, addition silicone rubber and red wax contaminated by Streptococcus salivarius, Fusobacterium nucleatum and five other bacteria in different suspension media were radiated for up to 18 min, and the number of colony forming units was compared to non-radiated controls. The effect of ultraviolet radiation differed among bacterial species and depended on the organic content in the suspension. Generally, the bacterial reduction after ultraviolet radiation was below 4 log steps and thus insufficient for disinfection of dental impressions.

  18. Biomedical and Environmental Sciences INFORMATION FOR AUTHORS

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Biomedical and Environmental Sciences, an international journal with emphasis on scientific findings in China, publishes articles dealing with biologic and toxic effects of environmental pollutants on man and other forms of life. The effects may be measured with pharmacological, biochemical, pathological, and immunological techniques. The journal also publishes reports dealing with the entry, transport, and fate of natural and anthropogenic chemicals in the biosphere, and their impact on human health and well-being.Papers describing biochemical, pharmacological, pathological, toxicological and immunological studies of pharmaceuticals (biotechnological products) are also welcome.

  19. 42 CFR Appendix G to Part 75 - Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography G Appendix G to Part 75 Public Health PUBLIC HEALTH SERVICE... EDUCATIONAL PROGRAMS FOR AND THE CREDENTIALING OF RADIOLOGIC PERSONNEL Pt. 75, App. G Appendix G to Part...

  20. 21 CFR 872.3240 - Dental bur.

    Science.gov (United States)

    2010-04-01

    ... materials intended for use in the fabrication of dental devices. (b) Classification. Class I (general... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dental bur. 872.3240 Section 872.3240 Food and... DENTAL DEVICES Prosthetic Devices § 872.3240 Dental bur. (a) Identification. A dental bur is a...

  1. 碳酸饮料对口腔健康及口腔材料的影响%Effects of Carbonated Drinks on Oral Health and Dental Material

    Institute of Scientific and Technical Information of China (English)

    袁荃; 张彬; 李金源

    2016-01-01

    ABSTRACT:Carbonated drinks as a fashion drink more and more popular with consumers.Especially young long-term heavy drinking carbonated beverages or other drinks instead of water phenomenon has become more prominent.And the problems caused by the health of carbonated beverages are gradually being concerned by scholars at home and abroad.Through access to information about carbonated drinks to the inlfuence of oral health and dental materials were reviewed as follows.%碳酸饮料作为一种时尚饮品越来越受到消费者欢迎,尤其是青少年长期大量饮用碳酸饮料替代水或其他饮品的现象也越发突出。而碳酸饮料对人体健康引起的问题也逐渐受到国内外学者的关注。通过查阅资料就有关碳酸饮料对口腔健康以及口腔材料方面的影响做如下综述。

  2. Radiographic signs and diagnosis of dental disease.

    Science.gov (United States)

    Bellows, J

    1993-08-01

    Dental radiographs are critical for the complete assessment and treatment of dental diseases. Dental radiography is commonly used to evaluate congenital dental defects, periodontal disease, orthodontic manipulations, oral tumors, endodontic treatments, oral trauma, and any situation where an abnormality is suspected. Although standard radiographic equipment and film can be used to produce dental radiographs, dental X-ray equipment and film provide superior quality images and greater convenience of animal patient positioning. An understanding of normal dental radiographic anatomy is important when interpreting dental radiographs. Stage III periodontitis is the earliest stage of periodontal disease at which radiographic abnormalities become apparent. Bone loss associated with periodontal disease can be classified as either horizontal or vertical. Periapical radiolucencies can represent granulomas, cysts, or abscesses, whereas periapical radiodensities may represent sclerotic bone or condensing osteitis. Lytic lesions of the bone of the jaw often represent oral neoplasms. Neoplasms also can displace or disrupt teeth in the dental arch. Resorptive lesions can be external or internal and appear as radiolucent areas involving the external surface of the root or the pulp cavity, respectively. Feline dental resorptive lesions, also known as odontoclastic resorptions, are a specific form of dental resorptive lesions unique to cats.

  3. "Smart" polymeric nanospheres as new materials for possible biomedical applications.

    Science.gov (United States)

    Szczubiałka, Krzysztof; Jankowska, Monika; Nowakowska, Maria

    2003-08-01

    Novel random terpolymers of N-isopropylacrylamide (NIPAM), sodium 2-acrylamido-2-methyl-1-propanesulfonate (AMPS), and cinnamoyloxyethylmethacrylate (CEMA) were synthesized by free radical copolymerization using AIBN as an initiator. Five terpolymers were obtained by copolymerization of the monomer mixtures containing a fixed amount of 10 mol % of AMPS while the content of CEMA ranged from 5 to 25 mol % and was changed in 5 mol % increments. The terpolymers obtained are water-soluble. Because of their amphiphilic nature they undergo self-organization in the aqueous solution with the formation of micelles capable of solubilizing sparingly water soluble organic compounds, such as drugs. The terpolymers are susceptible to three external stimuli, i.e. temperature, ionic strength and UV light. Due to the presence of NIPAM in the terpolymers they display the lower critical solution temperature (LCST), the presence of AMPS makes them sensitive to the ionic strength of the solution, while the light-responsiveness of the terpolymers is due to the presence of cinnamoyl chromophores, which undergo photodimerization when irradiated with UV light at about 280 nm. Application of any of these stimuli alone or in combination with other stimuli allows changing the copolymer properties in a controlled way.

  4. A Novel Approach to Design Chitosan-Polyester Materials for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Tatiana A. Akopova

    2012-01-01

    Full Text Available A novel approach to design chitosan-polyester materials is reported. The method is based on mechanical activation and effective intermixing of the substrates under high pressure and shear deformation in the course of solid-state reactive blending. The marked departure of this approach from previous practice resides on exploitation of a variety of chemical transformations of the solid polymers that become feasible under conditions of plastic flow. Low temperatures (above Tg but below the melting points of the crystalline polymers are maintained throughout the process, minimizing mechanical and oxidative degradation of the polymers. Morphology as well as structural, mechanical, and relaxation properties of those prepared blends of chitosan with semicrystalline poly(L,L-lactide and amorphous poly(D,L-lactide-co-glycolide has been studied. Grafting of polyester moieties onto chitosan chains was found to occur under employed pressures and shear stresses. The prepared polymer blends have demonstrated an amphiphilic behavior with a propensity to disperse in organic solvents that widens possibilities to transform them into promising materials for various biomedical applications.

  5. CMT for biomedical and other applications

    Energy Technology Data Exchange (ETDEWEB)

    Spanne, P. [ESRF, Grenoble (France)

    1997-02-01

    This session includes two presentations describing applications for x-ray tomography using synchrotron radiation for biomedical uses and fluid flow modeling, and outlines advantages for using monoenergetic x-rays. Contrast mechanisms are briefly described and several graphs of absorbed doses and scattering of x-rays are included. Also presented are schematic diagrams of computerized tomographic instrumentation with camera head. A brief description of goals for a real time tomographic system and expected improvements to the system are described. Color photomicrographs of the Berea Sandstone and human bone are provided, as well as a 3-D microtomographic reconstruction of a human vertebra sample.

  6. Zirconia as a Dental Biomaterial

    Directory of Open Access Journals (Sweden)

    Alvaro Della Bona

    2015-08-01

    Full Text Available Ceramics are very important in the science of dental biomaterials. Among all dental ceramics, zirconia is in evidence as a dental biomaterial and it is the material of choice in contemporary restorative dentistry. Zirconia has been applied as structural material for dental bridges, crowns, inserts, and implants, mostly because of its biocompatibility, high fracture toughness, and radiopacity. However, the clinical success of restorative dentistry has to consider the adhesion to different substrates, which has offered a great challenge to dental zirconia research and development. This study characterizes zirconia as a dental biomaterial, presenting the current consensus and challenges to its dental applications.

  7. 3rd International Conference on Nanotechnologies and Biomedical Engineering

    CERN Document Server

    Tiginyanu, Ion

    2016-01-01

    This volume presents the proceedings of the 3rd International Conference on Nanotechnologies and Biomedical Engineering which was held on September 23-26, 2015 in Chisinau, Republic of Moldova. ICNBME-2015 continues the series of International Conferences in the field of nanotechnologies and biomedical engineering. It aims at bringing together scientists and engineers dealing with fundamental and applied research for reporting on the latest theoretical developments and applications involved in the fields. Topics include Nanotechnologies and nanomaterials Plasmonics and metamaterials Bio-micro/nano technologies Biomaterials Biosensors and sensors systems Biomedical instrumentation Biomedical signal processing Biomedical imaging and image processing Molecular, cellular and tissue engineering Clinical engineering, health technology management and assessment; Health informatics, e-health and telemedicine Biomedical engineering education Nuclear and radiation safety and security Innovations and technology transfer...

  8. Influence of dental filling material type on the concentration of interleukin 9 in the samples of gingival crevicular fluid

    Directory of Open Access Journals (Sweden)

    Stefanović Vladimir

    2016-01-01

    Full Text Available Background/Aim. Several cytokines and lymphokines (IL1β, ENA78, IL6, TNFα, IL8 and S100A8 are expressed during dental pulp inflammation. Analysis of gingival crevicu-lar fluid (GCF offers a non-invasive means of studying gen-eral host response in oral cavity. Although GCF levels of various mediators could reflect the state of inflammation both in dental pulp and gingiva adjacent to a tooth, GCF samples of those without significant gingivitis could be inter-preted as reflection of pulpal process. The aim of this study was to investigate IL9 GCF values in patients with dental car-ies and to assess possible influence of various dental fillings materials on local IL9 production. Methods. The study group included 90 patients, aged 18–70, with inclusion and exclusion criteria in the prospective clinical study. Of the 6 types of material used for the restoration of prepared cavities, 3 were intended for temporary and 3 for definitive restora-tion. According to dental fillings weight, all the participants were divided into 3 groups: those with fillings lighter than 0.50 g, those with 0.50–1.00 g, and those with fillings heavier than 1.00 g. Samples were taken from gingival sulcus using the filter paper technique. Clinical parameters were deter-mined by bleeding index, plaque index (Silness-Lou, 0–3, gingival index (0–3, and gingival sulcus depth. Cytokine con-centrations were assessed using commercially available cy-tomix. Results. According to the weight of dental fillings, there was a clear decreament trend of IL9 values meaning that dental defects greater than 1.00 g of dental filling were associated with lower GCF IL9 concentration. The IL9 val-ues correlated with the degree of gingival index and depth of gingival sulcus, being higher with more advanced gingivitis and more pronounced anatomical changes in the tooth edge. Different filling materials exerted various local IL9 responses. Zink polycarbonate cement and amalgam fillings induced

  9. AAHA dental care guidelines for dogs and cats.

    Science.gov (United States)

    Holmstrom, Steven E; Bellows, Jan; Colmery, Ben; Conway, M Lana; Knutson, Kate; Vitoux, Jeanne

    2005-01-01

    The purpose of this document is to provide guidelines for the practice of companion animal dentistry for the veterinary profession. Dental care is necessary to provide optimum health and quality of life. Diseases of the oral cavity, if left untreated, are often painful and can contribute to other local or systemic diseases. This paper includes guidelines for materials and equipment, dental cleaning and evaluation, client communication, and pet home care.

  10. Trends in material choice for posterior restorations in an Israeli dental school: composite resin versus amalgam.

    Science.gov (United States)

    Ben-Gal, Gilad; Weiss, Ervin I

    2011-12-01

    According to a recent American Dental Association survey, posterior composite resin restorations now outnumber amalgam restorations in the United States. Dental schools around the world vary considerably in the extent to which they teach the use of composite resins. We aimed to determine if there has been an increase in the placement of posterior composite restorations in an Israeli dental school and if faculty experience affects the type of posterior restoration placed. In this retrospective study, we recorded and analyzed all the restorations performed by undergraduate students in the last five academic years at the Hebrew University Hadassah School of Dental Medicine in Jerusalem. All clinical records of student treatments between 2004 and 2009 were screened, and direct restorations were registered. Out of 6,094 posterior restorations performed during the study period, 42.3 percent were made of composite resin, increasing from 36.8 percent in 2004-05 to 48.5 percent in 2008-09, an increase of 11.7 percent. When clinical instructors were asked to state their preference if they themselves were to undergo posterior restoration, similar results were obtained. Instructors with less than ten years' experience preferred posterior composite resin restorations in 54.8 percent of the hypothetical situations, compared with 37.2 percent preferred by instructors with ten years of experience or more. It appears that the use of composite resin was influenced mainly by the prevailing trend and was not based on scientific evidence. Dental faculties should define criteria, based on up-to-date clinical studies, for using new materials, taking into consideration differences among instructors regarding treatment concept.

  11. Effects of Various Dental Materials on Alkaline Phosphatase Extracted from Pulp: An Experiment for the Biochemistry Laboratory.

    Science.gov (United States)

    Thompson, Lorin R.

    1980-01-01

    A laboratory experiment that demonstrates the effects of various dental materials on a representative enzyme from the pulp is outlined. The experiment encourages students to consider the effects that various restorative materials and techniques might have on enzymes in the living pulp. (Author/MLW)

  12. Pneumoconiosis and respiratory problems in dental laboratory technicians: Analysis of 893 dental technicians

    Directory of Open Access Journals (Sweden)

    Dilek Ergün

    2014-10-01

    Full Text Available Objectives: To explore the rate of pneumoconiosis in dental technicians (DTP and to evaluate the risk factors. Material and Methods: Data of 893 dental technicians, who were admitted to our hospital in the period January 2007–May 2012, from 170 dental laboratories were retrospectively examined. Demographic data, respiratory symptoms, smoking status, work duration, working fields, exposure to sandblasting, physical examination findings, chest radiographs, pulmonary function tests and high-resolution computed tomography results were evaluated. Results: Dental technicians’ pneumoconiosis rate was 10.1% among 893 cases. The disease was more common among males and in those exposed to sandblasting who had 77-fold higher risk of DTP. The highest profusion subcategory was 3/+ (according to the International Labour Organization (ILO 2011 standards and the large opacity rate was 13.3%. Conclusions: To the best of our knowledge, it was the largest DTP case series (N = 893/90 in the literature in English. Health screenings should be performed regularly for the early diagnosis of pneumoconiosis, which is an important occupational disease for dental technicians.

  13. World Congress on Medical Physics and Biomedical Engineering

    CERN Document Server

    2015-01-01

    This book presents the proceedings of the IUPESM World Biomedical Engineering and Medical Physics, a tri-annual high-level policy meeting dedicated exclusively to furthering the role of biomedical engineering and medical physics in medicine. The book offers papers about emerging issues related to the development and sustainability of the role and impact of medical physicists and biomedical engineers in medicine and healthcare. It provides a unique and important forum to secure a coordinated, multileveled global response to the need, demand, and importance of creating and supporting strong academic and clinical teams of biomedical engineers and medical physicists for the benefit of human health.

  14. Biomedical journals: keeping up and reading critically.

    Science.gov (United States)

    Chase, Karen L; DiGiacomo, Ronald F; Van Hoosier, Gerald L

    2006-09-01

    By extrapolation from studies of physicians, knowledge and practice of laboratory animal medicine and science are expected to become progressively more outdated the longer practitioners are out of school. Keeping up with current literature and practice is a challenge that necessitates the use of many different sources of continuing education. Both veterinarians and physicians consistently list journals as the most beneficial source of new information. Accordingly, they must select from the veterinary and biomedical literature articles that report original studies and systematic reviews and recognize and respond to valid new knowledge to improve diagnostic and therapeutic approaches and maintain consistent clinical skills. Other objectives include selecting journals for general information and for information relevant or specific to one's field of research. Lastly, candidates for board certification need to read articles from journals that potentially provide the basis for questions on the examination. 'High-impact' journals should be identified, and articles should be reviewed critically. In a survey of recent candidates for laboratory animal medicine board examination, these journals included Contemporary Topics (now JAALAS), Comparative Medicine, ILAR Journal, and Laboratory Animals. Strategies for coping with the challenge of staying current with the literature include wise use of technology, journal clubs, and consultation with colleagues. A laboratory animal practitioner can become a better scientist and clinician by evaluating the research performed by others. Thorough, critical review of biomedical literature is paramount to these goals.

  15. Localization and Tracking of Implantable Biomedical Sensors

    Directory of Open Access Journals (Sweden)

    Ilknur Umay

    2017-03-01

    Full Text Available Implantable sensor systems are effective tools for biomedical diagnosis, visualization and treatment of various health conditions, attracting the interest of researchers, as well as healthcare practitioners. These systems efficiently and conveniently provide essential data of the body part being diagnosed, such as gastrointestinal (temperature, pH, pressure parameter values, blood glucose and pressure levels and electrocardiogram data. Such data are first transmitted from the implantable sensor units to an external receiver node or network and then to a central monitoring and control (computer unit for analysis, diagnosis and/or treatment. Implantable sensor units are typically in the form of mobile microrobotic capsules or implanted stationary (body-fixed units. In particular, capsule-based systems have attracted significant research interest recently, with a variety of applications, including endoscopy, microsurgery, drug delivery and biopsy. In such implantable sensor systems, one of the most challenging problems is the accurate localization and tracking of the microrobotic sensor unit (e.g., robotic capsule inside the human body. This article presents a literature review of the existing localization and tracking techniques for robotic implantable sensor systems with their merits and limitations and possible solutions of the proposed localization methods. The article also provides a brief discussion on the connection and cooperation of such techniques with wearable biomedical sensor systems.

  16. Localization and Tracking of Implantable Biomedical Sensors.

    Science.gov (United States)

    Umay, Ilknur; Fidan, Barış; Barshan, Billur

    2017-03-13

    Implantable sensor systems are effective tools for biomedical diagnosis, visualization and treatment of various health conditions, attracting the interest of researchers, as well as healthcare practitioners. These systems efficiently and conveniently provide essential data of the body part being diagnosed, such as gastrointestinal (temperature, pH, pressure) parameter values, blood glucose and pressure levels and electrocardiogram data. Such data are first transmitted from the implantable sensor units to an external receiver node or network and then to a central monitoring and control (computer) unit for analysis, diagnosis and/or treatment. Implantable sensor units are typically in the form of mobile microrobotic capsules or implanted stationary (body-fixed) units. In particular, capsule-based systems have attracted significant research interest recently, with a variety of applications, including endoscopy, microsurgery, drug delivery and biopsy. In such implantable sensor systems, one of the most challenging problems is the accurate localization and tracking of the microrobotic sensor unit (e.g., robotic capsule) inside the human body. This article presents a literature review of the existing localization and tracking techniques for robotic implantable sensor systems with their merits and limitations and possible solutions of the proposed localization methods. The article also provides a brief discussion on the connection and cooperation of such techniques with wearable biomedical sensor systems.

  17. Localization and Tracking of Implantable Biomedical Sensors

    Science.gov (United States)

    Umay, Ilknur; Fidan, Barış; Barshan, Billur

    2017-01-01

    Implantable sensor systems are effective tools for biomedical diagnosis, visualization and treatment of various health conditions, attracting the interest of researchers, as well as healthcare practitioners. These systems efficiently and conveniently provide essential data of the body part being diagnosed, such as gastrointestinal (temperature, pH, pressure) parameter values, blood glucose and pressure levels and electrocardiogram data. Such data are first transmitted from the implantable sensor units to an external receiver node or network and then to a central monitoring and control (computer) unit for analysis, diagnosis and/or treatment. Implantable sensor units are typically in the form of mobile microrobotic capsules or implanted stationary (body-fixed) units. In particular, capsule-based systems have attracted significant research interest recently, with a variety of applications, including endoscopy, microsurgery, drug delivery and biopsy. In such implantable sensor systems, one of the most challenging problems is the accurate localization and tracking of the microrobotic sensor unit (e.g., robotic capsule) inside the human body. This article presents a literature review of the existing localization and tracking techniques for robotic implantable sensor systems with their merits and limitations and possible solutions of the proposed localization methods. The article also provides a brief discussion on the connection and cooperation of such techniques with wearable biomedical sensor systems. PMID:28335384

  18. Influence of dental restorative material properties on bond interface reliability: a finite element analysis

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yan-tao; ZHANG Yu-mei; HOU Shu-xun; KONG Liang; LIN Jun; ZHAO Yi-min; HUO Na

    2013-01-01

    Background Varieties of restorative materials are widely used in dentistry.The aim of this study is to explore the influence of different dental restorative materials on bond interface reliability.Methods A two-dimensional finite element analysis method was adopted to simulate the shear-bond efficacy test.The influence of elastic modulus and Poisson's ratio were investigated separately.Several dental restorative materials including resins,metals,and ceramics were analyzed in this study.Results The deformation and peak equivalent stress level of the dentin-adhesive interface rose sharply following a decrease in the elasticity of restorative materials,especially those with a low elastic modulus range.The influence of the Poisson's coefficient was not significant.Ceramics and gold alloy were preferred to resin composite in restorations bearing extensive shear load during service.Conclusions Restorative materials with an elastic modulus similar to that of teeth are not always the best clinical choice.This research provides a helpful guide for the application of different restorative materials in clinical practice.

  19. Process Development of Porcelain Ceramic Material with Binder Jetting Process for Dental Applications

    Science.gov (United States)

    Miyanaji, Hadi; Zhang, Shanshan; Lassell, Austin; Zandinejad, Amirali; Yang, Li

    2016-03-01

    Custom ceramic structures possess significant potentials in many applications such as dentistry and aerospace where extreme environments are present. Specifically, highly customized geometries with adequate performance are needed for various dental prostheses applications. This paper demonstrates the development of process and post-process parameters for a dental porcelain ceramic material using binder jetting additive manufacturing (AM). Various process parameters such as binder amount, drying power level, drying time and powder spread speed were studied experimentally for their effect on geometrical and mechanical characteristics of green parts. In addition, the effects of sintering and printing parameters on the qualities of the densified ceramic structures were also investigated experimentally. The results provide insights into the process-property relationships for the binder jetting AM process, and some of the challenges of the process that need to be further characterized for the successful adoption of the binder jetting technology in high quality ceramic fabrications are discussed.

  20. Fusing Manual and Machine Feedback in Biomedical Domain

    Science.gov (United States)

    2014-11-01

    Fusing manual and machine feedback in biomedical domain 1Jainisha Sankhavara, 1Fenny Thakrar, 2Shamayeeta Sarkar, 1Prasenjit Majumder 1DA-IICT...to obtain efficient biomedical document retrieval. We focused on fusing manual and machine feedback runs. Fusion run performs better and gives...retrieval of biomedical articles relevant for answering generic clini- cal questions about medical records. There are 30 topics provided, each

  1. Nanomaterials driven energy, environmental and biomedical research

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Prakash C.; Srinivasan, Sesha S.; Wilson, Jeremiah F. [Department of Physics, College of Arts and Sciences, Tuskegee University, Tuskegee, AL 36088 (United States)

    2014-03-31

    We have developed state-of-the-art nanomaterials such as nanofibers, nanotubes, nanoparticles, nanocatalysts and nanostructures for clean energy, environmental and biomedical research. Energy can neither be created nor be destroyed, but it can be converted from one form to another. Based on this principle, chemical energy such as hydrogen has been produced from water electrolysis at a much lower voltage using RuO{sub 2} nanoparticles on the Si wafer substrate. Once the hydrogen is produced from the clean sources such as solar energy and water, it has to be stored by physisorption or chemisorption processes on to the solid state systems. For the successful physical adsorption of hydrogen molecule, we have developed novel polyaniline nanostructures via chemical templating and electrospinning routes. Chemical or complex hydrides involving nano MgH{sub 2} and transition metal nanocatalysts have been synthesized to tailor both the thermodynamics and kinetics of hydrogen (chemi) sorption respectively. Utilization of solar energy (UV-Vis) and a coupling of novel semiconductor oxide nanoparticles have been recently demonstrated with enhancement in photo-oxidation and/or photo-reduction processes for the water/air detoxification and sustainable liquid fuel production respectively. Magnetic nanoparticles such as ZnFe{sub 2}O{sub 4} have been synthesized and optimized for biomedical applications such as targeted drug delivery and tumor diagnostic sensing (MRI)

  2. Nanomaterials driven energy, environmental and biomedical research

    Science.gov (United States)

    Sharma, Prakash C.; Srinivasan, Sesha S.; Wilson, Jeremiah F.

    2014-03-01

    We have developed state-of-the-art nanomaterials such as nanofibers, nanotubes, nanoparticles, nanocatalysts and nanostructures for clean energy, environmental and biomedical research. Energy can neither be created nor be destroyed, but it can be converted from one form to another. Based on this principle, chemical energy such as hydrogen has been produced from water electrolysis at a much lower voltage using RuO2 nanoparticles on the Si wafer substrate. Once the hydrogen is produced from the clean sources such as solar energy and water, it has to be stored by physisorption or chemisorption processes on to the solid state systems. For the successful physical adsorption of hydrogen molecule, we have developed novel polyaniline nanostructures via chemical templating and electrospinning routes. Chemical or complex hydrides involving nano MgH2 and transition metal nanocatalysts have been synthesized to tailor both the thermodynamics and kinetics of hydrogen (chemi) sorption respectively. Utilization of solar energy (UV-Vis) and a coupling of novel semiconductor oxide nanoparticles have been recently demonstrated with enhancement in photo-oxidation and/or photo-reduction processes for the water/air detoxification and sustainable liquid fuel production respectively. Magnetic nanoparticles such as ZnFe2O4 have been synthesized and optimized for biomedical applications such as targeted drug delivery and tumor diagnostic sensing (MRI).

  3. Advances in biomedical engineering and biotechnology during 2013-2014.

    Science.gov (United States)

    Liu, Feng; Wang, Ying; Burkhart, Timothy A; González Penedo, Manuel Francisco; Ma, Shaodong

    2014-01-01

    The 3rd International Conference on Biomedical Engineering and Biotechnology (iCBEB 2014), held in Beijing from the 25th to the 28th of September 2014, is an annual conference that intends to provide an opportunity for researchers and practitioners around the world to present the most recent advances and future challenges in the fields of biomedical engineering, biomaterials, bioinformatics and computational biology, biomedical imaging and signal processing, biomechanical engineering and biotechnology, amongst others. The papers published in this issue are selected from this conference, which witnesses the advances in biomedical engineering and biotechnology during 2013-2014.

  4. Polymer and polymer-hybrid nanoparticles from synthesis to biomedical applications

    CERN Document Server

    Rangelov, Stanislav

    2013-01-01

    Polymeric and hybrid nanoparticles have received increased scientific interest in terms of basic research as well as commercial applications, promising a variety of uses for nanostructures in fields including bionanotechnology and medicine. Condensing the relevant research into a comprehensive reference, Polymer and Polymer-Hybrid Nanoparticles: From Synthesis to Biomedical Applications covers an array of topics from synthetic procedures and macromolecular design to possible biomedical applications of nanoparticles and materials based on original and unique polymers. The book presents a well-r

  5. USE OF PLASTIC MATERIAL AND TRIPLE SCAN IN THE PREPARATION OF SURGICAL GUIDES FOR THE DENTAL IMPLANT TREATMENT-CASE REPORT

    Directory of Open Access Journals (Sweden)

    Rosen Borisov

    2016-09-01

    Full Text Available The use of surgical guides in implant treatment increases the accuracy of the dental implant positioning compared with manual methods. Regardless of how they are made, deviations of implants from their intended position are established in all kinds of surgical guides. This article considers the use of plastic material and new scanning technique for the production of CAD/CAM surgical guides that aim to overcome the deficiencies of the currently applied technologies in the production of surgical guides. Materials and methods: The study shows the techniques used to overcome degraded by metal artifacts CBCT images in implant treatment of patients with partial edentulism, and located medially to the defect metal-ceramic crowns. When planning implant treatment, a triple scan method has been implied. At the beginning, CBCT scan of the patient with a silicone impression material is made in the zone of interest. Secondly, CBCT scan only of the silicon impression is made, and thirdly - intraoral scanning of the patient with an intraoral scanner. Virtual analogues have been created of images from the three scans and have been repositioned one over another; as thereby an intraoral image have been accurately positioned over the CBCT image of the patient. Virtual planning of the implant positioning has been performed, and a model of surgical guide has been made for their placement. The guide has been printed with an SLA 3D printer technology of photopolymer with dualistic characteristics-rigid in the working part and plastic in the fixing part. Through it, implants have been placed to the treatment planning. Postoperative CBCT has been done on the patient to measure the implant deviation to their position in the treatment planning. Results: Axes angular deviation of the planned and placed implants has not been established. Average linear displacement of 240 μ (+/- 40 μ has been found. Conclusions: Using the triple scan method is possible to overcome the

  6. Application of ionizing radiation processing in biomedical engineering and microelectronics

    Energy Technology Data Exchange (ETDEWEB)

    Hongfej, H.; Jilan, W.

    1988-01-01

    The applied radiation chemistry has made great contributions to the development of polymeric industrial materials by the characteristics reaction means such as crosslinking, graft copolymerization and low-temperature or solid-phase polymerization, and become a important field on peaceful use of atomic energy. A brief review on the applications of ionizing radiation processing in biomedical engineering and microelectronics is presented. The examples of this technique were the studies on biocompatible and biofunctional polymers for medical use and on resists of lithography in microelectronics.

  7. Analysis of dental materials as an aid to identification in aircraft accidents

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, G.S.; Cruickshanks-Boyd, D.W.

    1982-04-01

    The failure to achieve positive identification of aircrew following an aircraft accident need not prevent a full autopsy and toxicological examination to ascertain possible medical factors involved in the accident. Energy-dispersive electron microprobe analysis provides morphological, qualitative, and accurate quantitative analysis of the composition of dental amalgam. Wet chemical analysis can be used to determine the elemental composition of crowns, bridges and partial dentures. Unfilled resin can be analyzed by infrared spectroscopy. Detailed analysis of filled composite restorative resins has not yet been achieved in the as-set condition to permit discrimination between manufacturers' products. Future work will involve filler studies and pyrolysis of the composite resins by thermogravimetric analysis to determine percentage weight loss when the sample examined is subjected to a controlled heating regime. With these available techniques, corroborative evidence achieved from the scientific study of materials can augment standard forensic dental results to obtain a positive identification.

  8. Dental Charting. Learning Activities, Unit Tests, Progress Chart, and Work Sheet.

    Science.gov (United States)

    Texas Univ., Austin. Center for Occupational Curriculum Development.

    These materials are part of a series dealing with skills and information needed by students in dental assisting. The individualized student materials are suitable for classroom, laboratory, or cooperative training programs. These student materials, designed to be used with the Dental Charting Student Manual, consist of learning activities, unit…

  9. Dental fear, regularity of dental attendance and subjective evaluation of dental erosion in women with eating disorders.

    Science.gov (United States)

    Willumsen, Tiril; Graugaard, Peter K

    2005-08-01

    This questionnaire study, with a response rate of 53%, examined self-induced vomiting, erosions and dental attendance in women with eating disorders (EDs) as well as dental fear and its effect on attendance and communication with the dentist. A survey of 371 responding women with EDs, who were recruited from a self-help organization, revealed that dental fear was higher in women with EDs compared to the general population. Dental fear was present in 32.1% of women with EDs, and very high dental fear was present in 16.5% of women with EDs. Of those with very high dental fear, 32.3% had not visited a dental clinic at all in the preceding 2 yr, and 43.5% only initiated contact when they had symptoms. Self-induced vomiting was especially frequent in women with bulimia nervosa (87.9%) and in those with more than one ED (the 'mixed group') (80.6%). Among those with self-induced vomiting, 45.3% thought that they had erosions, although only 28.4% had erosions diagnosed by a dentist. Of women with EDs, 61.4% failed to disclose their condition. High dental fear did not affect willingness to disclose the ED. We conclude that dentists should examine ED patients carefully for dental erosions. Moreover, they should realize that most ED patients avoid disclosing their disorder and that dental fear further complicates dental treatment in these patients.

  10. The chewing robot: a new biologically-inspired way to evaluate dental restorative materials.

    Science.gov (United States)

    Raabe, D; Alemzadeh, K; Harrison, A L; Ireland, A J

    2009-01-01

    This paper presents a novel in vitro dental wear simulator based on 6-6 parallel kinematics to replicate mechanical wear formation on dental materials and components, such as individual teeth, crowns or bridges. The human mandible, guided by a range of passive structures moves with up to six degrees of freedom (DOF). Currently available wear simulators lack the ability to perform these complex chewing movements. In addition simulators are unable to replicate the normal range of chewing forces as they have no control system able to mimic the natural muscle function controlled by the human central nervous system. Such discrepancies between true in vivo and simulated in vitro movements will influence the outcome and reliability of wear studies using such approaches. This paper summarizes the development of a new dynamic jaw simulator based on the kinematics of the human jaw.

  11. Biomedical Image Analysis by Program "Vision Assistant" and "Labview"

    Directory of Open Access Journals (Sweden)

    Peter Izak

    2005-01-01

    Full Text Available This paper introduces application in image analysis of biomedical images. General task is focused on analysis and diagnosis biomedical images obtained from program ImageJ. There are described methods which can be used for images in biomedical application. The main idea is based on particle analysis, pattern matching techniques. For this task was chosensophistication method by program Vision Assistant, which is a part of program LabVIEW.

  12. Analysis and modeling of noise in biomedical systems.

    Science.gov (United States)

    Ranjbaran, Mina; Jalaleddini, Kian; Lopez, Diego Guarin; Kearney, Robert E; Galiana, Henrietta L

    2013-01-01

    Noise characteristics play an important role in evaluating tools developed to study biomedical systems. Despite usual assumptions, noise in biomedical systems is often nonwhite or non-Gaussian. In this paper, we present a method to analyze the noise component of a biomedical system. We demonstrate the effectiveness of the method in the analysis of noise in voluntary ankle torque measured by a torque transducer and eye movements measured by electro-oculography (EOG).

  13. Keynote Lecture: The Problems and Challenges in Biomedical Sciences

    OpenAIRE

    Bruce Albert

    2015-01-01

    Distressed by the perverse incentives that have generated the current hyper-competitive biomedical research environment in the United States, four of us published an open-access article in April 2014 entitled: Rescuing US biomedical research from its systemic flaws (Alberts, B., Kirschner, Marc W., Tilghman, Shirley, and  Varmus, H.; Proc. Natl. Acad. Sci. USA 111, 5773-5777 (2014)). As announced in our follow-up piece, Opinion: Addressing systemic problems in the biomedical research enterpri...

  14. Modeling and control in the biomedical sciences

    CERN Document Server

    Banks, H T

    1975-01-01

    These notes are based on (i) a series of lectures that I gave at the 14th Biennial Seminar of the Canadian Mathematical Congress held at the University of Western Ontario August 12-24, 1973 and (li) some of my lectures in a modeling course that I have cotaught in the Division of Bio-Medical Sciences at Brown during the past several years. An earlier version of these notes appeared in the Center for Dynamical Systems Lectures Notes series (CDS LN 73-1, November 1973). I have in this revised and extended version of those earlier notes incorporated a number of changes based both on classroom experience and on my research efforts with several colleagues during the intervening period. The narrow viewpoint of the present notes (use of optimization and control theory in biomedical problems) reflects more the scope of the CMC lectures given in August, 1973 than the scope of my own interests. Indeed, my real interests have included the modeling process itself as well as the contributions made by investiga­ tors who e...

  15. Fraud and deceit in biomedical research

    Directory of Open Access Journals (Sweden)

    Buitrago Juliana

    2004-05-01

    Full Text Available History: Scientists are supposed to be moved by lofty ideals and be taught to work restlessly in pursue of the truth, but sadly fraud in biomedical research can be traced through the entire history of science. Definition: Nowadays, typology of fraud is clearly defined. Principal types of misconduct are reviewed. Consequences: It is impossible to know to what extent the damage will remain. Fraud threats public confidence in the integrity of science and may change professional attitudes and health public policies leading to serious social consequences. Evaluation of the problem: Prevalence of research fraud is unknown but in almost every country where investigation has been largely developed, at least a corroborated case of mis-conduct has been known. Policies on the scientific process may eventually contribute to fraudulent behaviour. Situation in Colombia: Colombia lacks of comprehensive policies to deal with fraud in research. How to tackle this problem: Finally, some recommendations are given to prevent, detect and deal with fraud in biomedical research.

  16. Elastomeric networks based on trimethylene carbonate polymers for biomedical applications : physical properties and degradation behaviour

    OpenAIRE

    Bat, Erhan

    2010-01-01

    The number of applications for biomedical technologies is ever-increasing, and there is a need to develop new materials with properties that can conform to the requirements of a specific application. Synthetic polymers are of great importance in the biomedical field as they can be designed to exhibit a wide range of physical- and biological properties and a range of degradation profiles. Interest in biodegradable elastomers is increasing, particularly for the engineering of soft and elastic t...

  17. Medical and biomedical research productivity from the Kingdom of Saudi Arabia (2008-2012)

    OpenAIRE

    Rabia Latif

    2015-01-01

    Background: Biomedical publications from a country mirror the standard of Medical Education and practice in that country. It is important that the performance of the health profession is occasionally documented. Aims: This study aimed to analyze the quantity and quality of biomedical publications from the Kingdom of Saudi Arabia (KSA) in international journals indexed in PubMed between 2008 and 2012. Materials and Methods: PubMed was searched for publications associated with KSA from 2008 to ...

  18. Soft skills and dental education.

    Science.gov (United States)

    Gonzalez, M A G; Abu Kasim, N H; Naimie, Z

    2013-05-01

    Soft skills and hard skills are essential in the practice of dentistry. While hard skills deal with technical proficiency, soft skills relate to a personal values and interpersonal skills that determine a person's ability to fit in a particular situation. These skills contribute to the success of organisations that deal face-to-face with clients. Effective soft skills benefit the dental practice. However, the teaching of soft skills remains a challenge to dental schools. This paper discusses the different soft skills, how they are taught and assessed and the issues that need to be addressed in their teaching and assessment. The use of the module by the Faculty of Dentistry, University of Malaya for development of soft skills for institutions of higher learning introduced by the Ministry of Higher Education, Malaysia.

  19. Mobile and portable dental services catering to the basic oral health needs of the underserved population in developing countries: a proposed model.

    Science.gov (United States)

    Ganavadiya, R; Chandrashekar, Br; Goel, P; Hongal, Sg; Jain, M

    2014-05-01

    India is the second most populous country in the world with an extensive rural population (68.8%). Children less than 18 years constitute about 40% of the population. Approximately, 23.5% of the urban population resides in urban slums. The extensive rural population, school children and the urban slum dwellers are denied of even the basic dental services though there is continuous advancement in the field of dentistry. The dentist to population ratio has dramatically improved in the last one to two decades with no significant improvement in the oral health status of the general population. The various studies have revealed an increasing trend in oral diseases in the recent times especially among this underserved population. Alternate strategies have to be thought about rather than the traditional oral health-care delivery through private dentists on fee for service basis. Mobile and portable dental services are a viable option to take the sophisticated oral health services to the doorsteps of the underserved population. The databases were searched for publications from 1900 to the present (2013) using terms such as Mobile dental services, Portable dental services and Mobile and portable dental services with key articles obtained primarily from MEDLINE. This paper reviews the published and unpublished literature from different sources on the various mobile dental service programs successfully implemented in some developed and developing countries. Though the mobile and portable systems have some practical difficulties like financial considerations, they still seem to be the only way to reach every section of the community in the absence of national oral health policy and organized school dental health programs in India. The material for the present review was obtained mainly by searching the biomedical databases for primary research material using the search engine with key words such as mobile and/or portable dental services in developed and developing countries

  20. Effect of dental materials on gluconeogenesis in rat kidney tubules

    Energy Technology Data Exchange (ETDEWEB)

    Reichl, F.X.; Durner, J.; Mueckter, H.; Elsenhans, B.; Forth, W. [Muenchen Univ. (Germany). Walter-Straub-Institut fuer Pharmakologie und Toxikologie; Kunzelmann, K.H.; Hickel, R. [Department of Operative/Restorative Dentistry, Periodontology and Pedodontics, Ludwig-Maximilians-University of Munich (Germany); Spahl, W. [Institute of Organic Chemistry, Ludwig-Maximilians-University of Munich (Germany); Hume, W.R. [Dental Research Institute, Univ. of California, Los Angeles, CA (United States); Moes, G.W. [TNO Prins-Maurits-Laboratorium, Rijswijk (Netherlands)

    1999-09-01

    The effect of dental composite components triethyleneglycoldimethacrylate (TEGDMA) and hydroxyethylmethacrylate (HEMA) as well as mercuric chloride (HgCl{sub 2}) and methylmercury chloride (MeHgCl) on gluconeogenesis was investigated in isolated rat kidney tubules. From starved rats kidney tubules were prepared and isolated by digestion with collagenase. Every 10 min up to 60 min 1-ml samples were drawn from the cell suspension for quantitating the glucose content. Glucose formation in controls was 3.3 {+-} 0.2 nmol/mg . per min (mean {+-} SEM, n=21). Relative rates of glucose formation were obtained by expressing individual rates as a percentage of the corresponding control. X-Y concentration curves (effective concentration, EC) of the substances were calculated by fitting a four-parametric sigmoid function to the relative rates of glucose formation at various test concentrations. At the end of the incubation period cell viability was assessed by trypan blue exclusion. Cell viability decreased within the 60 min interval from 90 to approx. 80% (controls), <25 (HEMA), <20 (TEGDMA), <10 (MeHgCl), and <10% (HgCl{sub 2}). Values of 50% effective concentration (EC{sub 50}) were calculated from fitted curves. EC{sub 50} values were (mmol; mean {+-} SEM; n=4): HEMA, 17.7 {+-} 2.9; TEGDMA, 1.8 {+-} 0.2; MeHgCl, 0.018 {+-} 0.0005; and HgCl{sub 2}, 0.0016 {+-} 0.0005. The toxic effect of HgCl{sub 2} was {proportional{underscore}to}1000 or 10 000 higher than that of the dental composite components TEGDMA or HEMA, respectively. (orig.)

  1. Biomedical Engineering Desk Reference

    CERN Document Server

    Ratner, Buddy D; Schoen, Frederick J; Lemons, Jack E; Dyro, Joseph; Martinsen, Orjan G; Kyle, Richard; Preim, Bernhard; Bartz, Dirk; Grimnes, Sverre; Vallero, Daniel; Semmlow, John; Murray, W Bosseau; Perez, Reinaldo; Bankman, Isaac; Dunn, Stanley; Ikada, Yoshito; Moghe, Prabhas V; Constantinides, Alkis

    2009-01-01

    A one-stop Desk Reference, for Biomedical Engineers involved in the ever expanding and very fast moving area; this is a book that will not gather dust on the shelf. It brings together the essential professional reference content from leading international contributors in the biomedical engineering field. Material covers a broad range of topics including: Biomechanics and Biomaterials; Tissue Engineering; and Biosignal Processing* A hard-working desk reference providing all the essential material needed by biomedical and clinical engineers on a day-to-day basis * Fundamentals, key techniques,

  2. Disparities in unmet dental need and dental care received by pregnant women in Maryland.

    Science.gov (United States)

    Singhal, Astha; Chattopadhyay, Amit; Garcia, A Isabel; Adams, Amy B; Cheng, Diana

    2014-09-01

    To examine prenatal dental care needs, utilization and oral health counseling among Maryland women who delivered a live infant during 2001-2003 and identify the factors associated with having a dental visit and having an unmet dental need during pregnancy. Pregnancy Risk Assessment Monitoring System is an ongoing population based surveillance system that collects information of women's attitudes and experiences before, during, and shortly after pregnancy. Logistic regression was used to model dental visits and unmet dental need using predictor variables for Maryland 2001-2003 births. Less than half of all women reported having a dental visit and receiving oral health advice during pregnancy. Twenty-five percent of women reported a need for dental care, of which 33 % did not receive dental care despite their perceived need. Multivariate