ABSTRACT
Polyetheretherketone (PEEK) has been widely applied in orthopedics because of its excellent mechanical properties, radiolucency, and biocompatibility. However, the bioinertness and poor osteointegration of PEEK have greatly limited its further application. Growing evidence proves that physical factors of implants, including their architecture, surface morphology, stiffness, and mechanical stimulation, matter as much as the composition of their surface chemistry. This review focuses on the multiple strategies for the physical modification of PEEK implants through adjusting their architecture, surface morphology, and stiffness. Many research findings show that transforming the architecture and incorporating reinforcing fillers into PEEK can affect both its mechanical strength and cellular responses. Modified PEEK surfaces at the macro scale and micro/nano scale have positive effects on cell-substrate interactions. More investigations are necessary to reach consensus on the optimal design of PEEK implants and to explore the efficiency of various functional implant surfaces. Soft-tissue integration has been ignored, though evidence shows that physical modifications also improve the adhesion of soft tissue. In the future, ideal PEEK implants should have a desirable topological structure with better surface hydrophilicity and optimum surface chemistry.
Subject(s)
Benzophenones , Ketones/chemistry , Polyethylene Glycols/chemistry , Polymers/chemistry , Surface PropertiesABSTRACT
ABSTRACT: There is insufficient information about the chairside polishing methods of polyether ether ketone material. Therefore, it is aimed in this study to investigate the effects of different polishing processes on polyether ether ketone surface roughness and hardness. A total of 66 disc-shaped specimens made of polyether ether ketone were used in this study. The specimens were polished conventionally and randomly divided into three groups (n=22). One group was designated as the control group, and no further treatment was applied. In the other two groups, the specimens' surfaces were abraded with diamond burs and polished using two different polishing kits. Their surface roughness and Vickers hardness were measured, and environmental scanning electron microscopy and atomic force microscopy examinations were performed. The data were statistically analysed using analysis of variance and Tukey's honest significant difference test (α=0.05). There were no statistically significant differences between the control and polishing kit groups in terms of either surface roughness or Vickers hardness (p>0.05). The polishing kits can be used reliably and effectively for polishing polyether ether ketone materials.
RESUMEN: No existe información suficiente sobre los métodos de pulido del material poliéter éter cetona. Por tanto, este estudio tiene como objetivo evaluar el efecto de diferentes procedimientos de pulido sobre la rugosidad y dureza de superficie de un material a base de poliéter éter acetona. Un total de 66 muestras en forma de disco fueron realizadas. Los especímenes fueron divididos en tres grupos (n=22). Un grupo fue designado como grupo de control, siendo que no se aplicó ningún tratamiento. En los otros dos grupos, las superficies de las muestras se lijaron con fresas de diamante y se pulieron con dos kits de pulido diferentes. Se investigó la rugosidad de superficie y la dureza Vickers en los diferentes grupos. También fueron evaluadas muestras representativas en microscopía electrónica de barrido y microscopía de fuerza atómica. Los datos se analizaron estadísticamente mediante el análisis de varianza (ANOVA) y el método de Tukey (α=0.05). No hubo diferencias estadísticamente significativas entre los grupos en términos de rugosidad de superficie o Dureza Vickers (p>0,05). Los kits de pulido se pueden utilizar de forma eficaz para el pulido de materiales a base de poliéter éter acetona.
Subject(s)
Polyethylenes , Dental Polishing , Dentifrices/analysisABSTRACT
OBJECTIVE@#To provide the basis for the clinical development of ultrasonic shoulder preparation by comparing the roughness and three-dimensional topography of shoulder surface between ultrasonic instruments and conventional rotary instruments, to make preliminary suggestions for clinical use of ultrasonic instruments.@*METHODS@#(1) Four areas of buccal and palatal surfaces of six extracted human premolars were prepared with different grit size of rotary instruments. Polyether was used to take impression of the shoulder area, 3-D topography measurement laser microscope (3-D TMLM) was used to scan the impressions and compare the shoulder surface roughness of the four areas. (2) Six extracted human premolars were prepared, mesial half of the shoulder was finished with traditional rotary instruments and distal half with ultrasonic instruments. Polyether was used to take impression of the shoulder area, 3-D TMLM was used to scan the impressions and compare the shoulder surface roughness and 3-D topography, and the shoulder surface morphology was observed by surgical microscope (×25 magnification). (3) Twenty extracted human maxillary symmetrical homonymous anterior teeth were poured into die stone using artificial gingiva, ultrasonic instruments group and rotary instruments group were divided randomly. After preparing the teeth and taking the shoulder impression with polyether in dental simulate on the training system, the surface roughness of the shoulder impression in mesial, middle and distal areas was scanned and compared. The data were analyzed using SPSS 25.0 software package.@*RESULTS@#(1) There was no significant difference in Ra and Rz values between the abutment shoulder and impression shoulder in different areas. (2) The surface roughness of the shoulder impression prepared by ultrasonic instruments [Ra:(6.59±2.33) μm, Rz:(34.69±7.29) μm] was significantly smaller than that of the rotary instruments [Ra:(21.79±4.89) μm, Rz:(91.69±14.82) μm] (P < 0.05). The morphology of the shoulder prepared by ultrasonic instruments was clear and continuous under microscope observation. (3) The surface roughness of each area of the shoulder prepared by ultrasonic instruments was significantly lower than that of the rotary instruments (P < 0.001); there was no significant difference of the surface roughness (Ra) in each area of the shoulder impression after ultrasonic instrument preparation, while the shoulder impression roughness in the mesial and distal areas was significantly higher than that in the middle area (P < 0.001) after rotary instrument preparation.@*CONCLUSION@#Compared with the rotary instruments, the ultrasonic instruments can obtain a smoother shoulder surface, especially can significantly improve the shoulder preparation effect near the proximal surface.
Subject(s)
Humans , Bicuspid , Microscopy, Electron, Scanning , Shoulder , Surface Properties , UltrasonicsABSTRACT
Objective: To propose a method for making organ-on-a-chip based on 3D printing, and study the relationship between cell growth on the chips and various factors. Methods: Through 3D printing technology and surface microstructure transfer method, ulcer-like and ridge-like mi-crostructures of the tumor surface and the intestinal villi were fabricated on a polydimethylsiloxane (PDMS) chip. Combined with fluorescence imaging, the effects of surface modification, shapes and heights of microstructures, and culture time on the surface coverage and density of Caco-2 cells on the chip were measured. Results:The PDMS chip was more likely to induce cell adhesion and growth rather than the 3D printing resin chip. On the surface of three-dimensional structure, cell surface coverage and cell density increased after the surface was treated with rat tail collagen (P0.05). Conclusion: The intestinal villi and tumor topological organ chips can be fabricated by 3D printing technology and surface microstructure transfer method. The surface modification and microstructure height affect the cell growth on the surface.
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Abstract This report introduced the description of two different species of digenean parasites isolated from the intestine of Rhinopoma hardwickii with new host and locality records in Egypt. The recovered helminthes were studied morphologically and morphometrically by light microscopy and the surface topography of the two species was elucidated by scanning electron microscopy (SEM). Urotrema scabridum had an elongated body, testes were tandem, ovaries were pretesticular, and vitelline follicles were observed in 2 lateral fields. SEM showed that the anterior half was covered with random and backwardly directed tegument spines. The lumen of the oral sucker was as a longitudinal slit encircled with type I dome-shaped papillae. The ventral sucker was wrinkled and covered by tongue-shaped tegument spines and several scattered papillae. Renschetrema indicum had a fusiform body with minute spines densely distributed in the anterior part of the body; testes sub-triangular, ovary fusiform; vitellaria were randomly distributed around the ceca and genital organs. SEM showed that the fore-body was ventrally concave and surrounded by cytoplasmic ridges equipped with numerous closely packed claw-shaped spines. The oral sucker was externally surrounded by two circles of papillae while the lip of the ventral sucker was rounded and surrounded by three papillae located in its upper end and anterolaterally.
Resumo O trabalho descreve duas espécies diferentes de parasitas digêneos isolados do intestino de Rhinopoma hardwickii, com novos registros de hospedeiros e localidade no Egito. Os helmintos recuperados foram estudados morfologicamente e morfometricamente por microscopia óptica, e a topografia superficial das duas espécies foi verificada por microscopia eletrônica de varredura (MEV). Urotrema scabridum apresenta um corpo alongado, testículos em tandem, ovários localizados pré-testiculares e os folículos vitelinos foram observados em 2 campos laterais. A microscopia eletrônica (ME) mostrou que a metade anterior do tegumento estava coberta com espinhos aleatoriamente e voltados para trás. O lúmen da ventosa oral apresentava-se como uma fenda longitudinal cercada de papilas em forma de cúpula tipo I. A ventosa ventral estava enrrugada e coberta por espinhos no tegumento em forma de língua e com várias papilas dispersas. Renschetrema indicum tinha um corpo fusiforme com espinhos diminutos densamente distribuídos na parte anterior do corpo; testículos sub-triangulares, ovários fusiformes; as glândulas vitelínicas estavam distribuídas aleatoriamente em torno do ceco e dos órgãos genitais. À ME a região anterior mostrou-se ventralmente côncava e cercada por cristas citoplasmáticas equipadas com numerosos espinhos em forma de unhas muito próximos. A ventosa oral apresentou-se externamente cercada por duas fileiras de papilas, enquanto a borda da ventosa ventral mostrou-se arredondada e cercada por três papilas localizadas na sua extremidade superior e antero-lateralmente.
Subject(s)
Animals , Male , Female , Trematoda/ultrastructure , Chiroptera/parasitology , Trematoda/isolation & purification , Trematoda/classification , Microscopy, Electron, Scanning , Chiroptera/classification , EgyptABSTRACT
Objective To investigate the application of 3-D scanning in the diagnosis and evaluation of pectus excava-tum.Methods From July 2016 to June 2017, chest CT concomitant 3-D scanning were performed in 90 pectus excavatum pa-tients before Nuss procudure.Another 30 cases underwent chest CT scanning for non-chest deformity causes were chosen as a control group.The transverse and anterior-posterior maximum diameter through the deepest point of chest wall deformity were measured.The surface topography index and Haller index were calculated respectively .Results There was a positive correla-tion between CT and 3-D scanning diameters of the transverse and anterior-posterior maximum diameters, and consistency rates were 94% and 82%, respectively.There was significant difference between pectus excavatum group 1.82 ±0.21 and control group 1.41 ±0.07 in the STI(P<0.001).There was a positive correlation between Haller index 5.12 ±3.36 and STI 1.82 ± 0.21, and consistency rate was 89%.The Delong's test showed no significant difference between ROC of HI and STI(Z =1.18, P=0.28).Conclusion 3-D scanning and STI of pectus excavatum is a validated alternative for CT and Haller index, especially in the infant and non-surgical treatment PE cases.
ABSTRACT
Objective@#To investigate the effect of pure titanium surface of large diameter TiO2 nanotubes modified by RGD peptide on the adhesion and proliferation of MG63 osteoblasts. to provide theoretical proof for developing titanium implants.@*Methods@#Commercially pure titanium discs were divided into four groups and treated with SLA to obtain a microrough surface (SLA group). Then, nanotubes were imposed on this microrough surface by anodization (SLA+80 group). The surface was then modified by dopamine (DOPA) (DOPA Group), after which bioactive RGD peptide layers were generated on the TiO2 nanotube surfaces via electrochemical and molecular self-assembly techniques (RGD group). The titanium surface morphology and elemental composition of each group were characterized by field emission scanning electron microscopy (FE-SEM) and X-ray photoelectron spectroscopy (XPS). MG63 cells were cultured in vitro to evaluate biological activities of titanium before and after treatment, including the evaluation of early-stage cell adhesion capacity by fluorescence microscopy, proliferation capacity by MTS assay, and mRNA expression of the cell osteoblast-related genes alkaline phosphatase (ALP) and osteocalcin (OCN) by qRT-PCR.@*Results@#FE-SEM and XPS showed that hierarchical micro/nanosurfaces decorated with TiO2 nanotubes were produced on titanium using sandblasting and large grit etching combined with anodization, dopamine was then self-polymerized to form a polydopamine film on the TiO2 nanotube surfaces, and RGD peptides were then conjugated to the polydopamine film, finally forming RGD peptide-modified bioactive layers. In vitro experiments showed that compared with the other three materials, the RGD-modified material was more conducive to cell adhesion and proliferation (P < 0.05). The expression levels of ALP and OCN mRNA in the RGD group were significantly higher than those in the SLA group and DOPA group (P < 0.05).@*Conclusion@#Hierarchical micro/nanosurfaces decorated with TiO2 nanotubes functionally modified with RGD peptides have good biocompatibility and could be used for developing titanium implants and further improving early osseointegration.
ABSTRACT
Aim: To evaluate the changes in surface topography and roughness of stainless steel (SS), nickel‑titanium and beta‑titanium (β‑Ti) archwires after clinical use and sterilization. Settings and Design: Thirty wires each of SS, nitinol, and β‑Ti (3M Unitek) were tested in as received, as received and autoclaved, and clinically retrieved then autoclaved conditions. Materials and Methods: A sterilization protocol of 134°C for 18 min was performed using an autoclave. Surface topography of specimens from each subgroup was examined using an environmental scanning electron microscope (ESEM model Quanta 200, The Netherlands) at ×100, ×1000, and ×2500 magnifications. Surface roughness was measured using arithmetic mean roughness (Ra) values obtained from optical profilometric scanning (Taylor Hobson, Leicester, UK). Statistical Analysis: Data were analyzed by one‑way analysis of variance and Tukey’s post‑hoc procedures. Results: Scanning electron microscope images revealed an increase in surface irregularities in SS and nitinol wires after clinical use. There was a significant increase in Ra values of SS orthodontic wires after intra‑oral exposure (P = 0.0002). Conclusion: Surface roughness of SS wires increased significantly after clinical use. Autoclave sterilization did not affect considerably on surface characteristics of any archwire.
ABSTRACT
PURPOSE: To describe and characterize the surface topography and cleanliness of CAD/CAM manufactured zirconia abutments after steaming and ultrasonic cleaning. MATERIALS AND METHODS: A total of 12 ceramic CAD/CAM implant abutments of various manufacturers were produced and randomly divided into two groups of six samples each (control and test group). Four two-piece hybrid abutments and two one-piece abutments made of zirconium-dioxide were assessed per each group. In the control group, cleaning by steam was performed. The test group underwent an ultrasonic cleaning procedure with acetone, ethyl alcohol and antibacterial solution. Groups were subjected to scanning electron microscope (SEM) analysis and Energy-dispersive X-ray spectroscopy (EDX) to verify and characterize contaminant chemical characterization non-quantitatively. RESULTS: All zirconia CAD/CAM abutments in the present study displayed production-induced wear particles, debris as well as organic and inorganic contaminants. The abutments of the test group showed reduction of surface contamination after undergoing an ultrasonic cleaning procedure. However, an absolute removal of pollutants could not be achieved. CONCLUSION: The presence of debris on the transmucosal surface of CAD/CAM zirconia abutments of various manufacturers was confirmed. Within the limits of the study design, the results suggest that a defined ultrasonic cleaning process can be advantageously employed to reduce such debris, thus, supposedly enhancing soft tissue healing. Although the adverse long-term influence of abutment contamination on the biological stability of peri-implant tissues has been evidenced, a standardized and validated polishing and cleaning protocol still has to be implemented.
Subject(s)
Acetone , Ceramics , Ethanol , Spectrum Analysis , Steam , UltrasonicsABSTRACT
PURPOSE: To describe and characterize the surface topography and cleanliness of CAD/CAM manufactured zirconia abutments after steaming and ultrasonic cleaning. MATERIALS AND METHODS: A total of 12 ceramic CAD/CAM implant abutments of various manufacturers were produced and randomly divided into two groups of six samples each (control and test group). Four two-piece hybrid abutments and two one-piece abutments made of zirconium-dioxide were assessed per each group. In the control group, cleaning by steam was performed. The test group underwent an ultrasonic cleaning procedure with acetone, ethyl alcohol and antibacterial solution. Groups were subjected to scanning electron microscope (SEM) analysis and Energy-dispersive X-ray spectroscopy (EDX) to verify and characterize contaminant chemical characterization non-quantitatively. RESULTS: All zirconia CAD/CAM abutments in the present study displayed production-induced wear particles, debris as well as organic and inorganic contaminants. The abutments of the test group showed reduction of surface contamination after undergoing an ultrasonic cleaning procedure. However, an absolute removal of pollutants could not be achieved. CONCLUSION: The presence of debris on the transmucosal surface of CAD/CAM zirconia abutments of various manufacturers was confirmed. Within the limits of the study design, the results suggest that a defined ultrasonic cleaning process can be advantageously employed to reduce such debris, thus, supposedly enhancing soft tissue healing. Although the adverse long-term influence of abutment contamination on the biological stability of peri-implant tissues has been evidenced, a standardized and validated polishing and cleaning protocol still has to be implemented.
Subject(s)
Acetone , Ceramics , Ethanol , Spectrum Analysis , Steam , UltrasonicsABSTRACT
Tissue engineering is a new field of which the main purpose is to regenerate and repair the damaged tissues. Scaffolds serve as three dimensional matrices for neo-organogenesis and their substance can be biologic or synthetic. Natural polymers have good interactions with the cells and synthetic biomaterials are also highly useful in biomedical application because of their biocompatible properties. In addition to scaffold substance, surface properties of biomaterials have an important role in tissue engineering. In this study, we examined whether substrate substance is important for wound healing or its surface topography. Therefore, we fabricated two matrices, electrospun polycaprolactone (PCL) nanofibers and collagen/chitosan film, and implanted them to the same rat models. After 2 weeks, the sizes of healing wounds were measured and their cellular structures were evaluated by histochemistry and mmunohistochemistry. Histological staining showed a good level of cellularization and epidermis-dermis formation in PCL implant while no determinable epithelium was observed after 2 weeks in collagen-chitosan graft. Immunohistochemical study demonstrated the highly expressed pancytokeratin in PCL graft while its expression was weak in underdeveloped epidermis of collagen-chitosan implantation. In conclusion, this study suggested that PCL nanofibers with high surface area had a more ideal property than natural collagen-chitosan film, therefore the structure and topography of a matrix seemed to be more important in wound healing than its material substance.
Subject(s)
Biocompatible Materials , Cellular Structures , Collagen , Epidermis , Epithelium , Models, Animal , Nanofibers , Polymers , Skin , Surface Properties , Tissue Engineering , Transplants , Wound Healing , Wounds and InjuriesABSTRACT
Copper NiTi wires were This latest innovation in the evolutionary scale gives us the opportunity of choosing the force level by choosing the temperature at which the wires will deliver its optimum force level. With so many advantages and their ability to return to their original form coupled with the high cost of copper NiTi many clinicians started reusing the wire. This raises concern about disinfecting/sterilizing the wire before using in another patient for prevention of cross infection. Hence, various sterilization procedures like cold sterilization using 2% acidic Glutaraldehyde, dry heat sterilization and autoclaving were used to prevent this cross infection . Aim: The main aim of this study is used to evaluate the effects of different kinds of sterilization on Modulus of elasticity and surface topography of the 0.016 copper NiTi wires before and after sterilization procedure Materials and Methods: In the present study, Three point bending test along with tensile test was performed to evaluate the modulus of elasticity. Scanning electron microscope pictures were used to evaluate surface topography changes. Results: Pretreatment and post treatment values were statistically analyzed by one way ANOVA test. No detrimental changes were detected in tensile properties of copper NiTi were after single cycle of sterilization with any of the stated sterilants. Very minimal non significant changes occurred during the second cycle of sterilization procedure. There was no changes in surface topography of the wire either with dry heat or autoclaving. However, on second treatment cycle with 2% glutaraldehyde, some amount of surface pitting was seen. Conclusion: Dry heat sterilization and autoclaving have been found to have very minimal changes on the tensile properties of these wires after one or two cycles of sterilization procedures, but not statistically significant. No detrimental effect was found on surface topography with dry heat or autoclaving. Results support the use of these sterilization procedures as part of infection control process, if the clinician select to reuse these wires for one time only. However, of late, since there is easy availability and modest cost of these wires it is recommended to use new wires which are supplied sealed sterilized packs for each patient to comply with present admissible standard of hygiene and sterilization.
ABSTRACT
Gotocotyla acanthura (Parona & Perugia, 1896) Meserve, 1938 collected from the gills of Pomatomus saltatrix from the coast of the state of Rio de Janeiro state was analyzed using scanning electron microscopy (SEM). The study demonstrated the presence of a buccal cavity, a genital atrium on the ventral surface and a muscular structure on the dorsal surface at the level of the body constriction. An elongated haptor with 80 to 120 pedunculated clamps symmetrically distributed in two rows, with rib-like thickenings and a curved lappet bearing a pair of hooks at the posterior extremity of the body were also observed. The cirrus could be seen protruding from the genital atrium, armed with pectinate spines along its length and presenting up to eight pointed spines around the genital atrium.
Gotocotyla acanthura (Parona & Perugia, 1896) Meserve, 1938, coletado das brânquias de Pomatomus saltatrix do litoral do Estado do Rio de Janeiro, foi estudado por microscopia eletrônica de varredura (MEV). O estudo demonstrou a presença de uma cavidade bucal, átrio genital na superfície ventral e uma estrutura muscular na superficie dorsal ao nível da constricção do corpo. Na extremidade posterior do corpo, foi observado o haptor alongado, apresentando 80 a 120 pinças pedunculadas, distribuídas em duas fileiras simétricas e uma porção terminal curvada provida de um par de ganchos. O cirro foi visualizado projetando-se do átrio genital, armado com espinhos pectinados ao longo do seu comprimento, apresentando até 8 espinhos pontiagudos ao redor do átrio.
Subject(s)
Animals , Perciformes/parasitology , Platyhelminths/ultrastructure , Brazil , Microscopy, Electron, Scanning , Platyhelminths/isolation & purificationABSTRACT
The attachment of cells to titanium surfaces is an important phenomenon in the area of clinical implant dentistry. A major consideration in designing implants has been to produce surfaces that promote desirable responses in the cells and tissues. To achieve these requirements, the titanium implant surface can be modified in various ways. This review mainly focuses on the surface topography of dental implants currently in use, emphasizing the association of reported variables with biological outcome.
Subject(s)
Biocompatible Materials/chemistry , Coated Materials, Biocompatible/chemistry , Dental Etching/methods , Dental Implants , Dental Materials/chemistry , Dental Prosthesis Design , Humans , Osseointegration/physiology , Surface Properties , Titanium/chemistryABSTRACT
Objective To evaluate the biological potential of surface topography of biomimetic matrix combined PRP gels with RGD modification. Methods Surface topography of nβ-TCP/Cs/PCL matrix was made by Nd: YAG laser, tissue-engineered bone was constructed in the following ways: ADSCs were loaded to nβ-TCP/Cs/PCL matrix with PRP gels plus RGD modification (group A), ADSCs were cultured to nβ-TCP/Cs/PCL matrix with RGD modification (group B), ADSCs implantation with topography-surfaced treatment of matrix (group C), ADSCs cultivation with smooth-surfaced treatment of matrix (group D). SEM and CLM were used to observe cellular pattern, survival rate, cell activity, ALP and collagen type Ⅰ level were detected at 1, 4, 8, 12, 16, 20, 24,28 days. Runx2 and OPG expressions were assayed at different interval. Results Under observation of SEM and CLM, new tissue showed more remarkable cell proliferation with abundant ECM in group A. Compared with other groups, the survival rate in group A was significantly higher (88.16 ± 1.29, P ＜ 0.05),and the level of cell activity, ALP, collagen type Ⅰ were significantly higher (0.92± 0.13, 87.27 ± 3.08, 93.27 ± 3.91, P＜ 0.05), and remarkable expression of Runx2 and OPG was also seen. Conclusion Topography-surfaced treatment of matrix combined PRP gels with RGD modification enhances the cell proliferation and acts as a feasible osteopromotive method.
ABSTRACT
El éxito de la oseointegración de los implantes dentales endóseos depende de una técnica quirúrgica y protésica apropiada, el diseño del implante y las propiedades del material del implante. Debido a los múltiples sistemas de implantes dentales existentes en el mercado, con diferentes diseños y materiales, se dificulta la selección de un sistema de implante ideal para una situación clínica específica. Las aleaciones metálicas y los cuerpos cerámicos son los materiales más comunes utilizados para la fabricación de los implantes dentales endóseos. Existen diferentes tratamientos para modificar la topografía superficial del implante, como los recubrimientos de hidroxiapatita (HA), el arenado con partículas de óxido de aluminio (Al2O3), el rociado con plasma de titanio (T.P.S.) y el grabado ácido. La rugosidad superficial de estos recubrimientos le permiten al tejido óseo penetrar en las irregularidades superficiales y aumentar la interacción biomecánica del implante con el hueso y aumentar la cantidad de hueso alrededor del implante dental
The success of dental implant osseointegration depends on the right surgical-prosthodontic protocol, implant design and material properties. Because of the many implant systems availables in the market with different material and designs it is difficult to choose which system is suitable for a specific clinical situation. Alloys and ceramics are the most frequent material used to fabricate dental implants. There are different treatments to modify the implant surface topography, these includes hydroxyapatite-coatings, titanium plasma-sprayed, sandblasted, and acid-ethed.The surface roughness obtained by these surface treatments promotes the penetration and growth of osseous tissue in the irregularities of the surface.The bone growth in the surface irregularities obtained by these treatments improved the implant-bone interface, and the extension of the bone around the dental implant
Subject(s)
Female , Dental Implants , Osseointegration , Surgery, Oral , DentistryABSTRACT
STATEMENT OF PROBLEM: In its preceding work, change in surface characteristics were investigated in consideration that both microtopograpy and macroscopic configuration of implants surface are two of the most important factors, in that they can construct agreeable environment by raising surface energy, to affect osseointegration and biocompatibility explained by cell proliferation. PURPOSE: This study focused on examining cytocompatibility of dental implants materials Ti-Ag alloys, of which mechanical and electrochemical superiority to cp-Ti or Ti6Al4V were verified, in comparison with that of cp-Ti, and Ti6Al4V. MATERIALS AND METHODS: In this regard, MTT tests for L-929, the fibroblast connective tissues and cell proliferation tests for osteoprogenitor cells, MC3T3-E1 were performed on cp-Ti, Ti6Al4V, and Ti-Ag alloys following thermal oxidation according to appropriate heat treatment temperature(untreated, 400, 600, 800degrees C) and heat treatment duration(untreated, 0.5, 1, 4 hr). RESULTS: The MTT tests on fibroblasts L-929 resulted in cell viability of over 90% in all experimental group entities, where, especially, the 100% of the viability for Ti-Ag alloys specimens accounted for the slightest adverse effect of ions release from those alloys on the cell. In MC3T3-E1 proliferation tests, the population of cells in the experimental group was roughly increased as experimentation proceeded, after two to four days. Proliferation showed highest viability for most of specimens, including Ti2.0Ag, treated at 600degrees C. CONCLUSION: In conclusion, it is the heat treatment temperature, not the duration that has considerable effects on thermal oxidation of specimens. Ti-Ag alloys treated at 600degrees C proved to have the best surface morphology as well as cytocompatibility when compared with Ti or Ti6Al4V for short-term biocompatibility tests.
Subject(s)
Alloys , Cell Proliferation , Cell Survival , Connective Tissue , Dental Implants , Fibroblasts , Hot Temperature , Ions , OsseointegrationABSTRACT
The purpose of this study was to investigate the property of a new Korean stainless steel wire(Jinsung Ind.) comparing with other foreign products. Five types of stainless steel wires (Standard, Resilient, HI-T of Unitek, Stainless steel of Ormco and Jinsung Ind.) in 0.016x0.022 and 0.019x0.025were tested to observe for composition analysis, size difference, tensile properties, flexure bending property, tortion property, surface hardness and surface topography by means of SEM. The findings suggest that: 1. In maximum tensile strength of tensile properties, Unitek Hi-T showed the greatest value, followed by Unitek Resilient, Jinsung Stainless Steel, Ormco Stainless Steel, Unitek Standard in 0.016x0.022, and Unitek Hi-T showed highest value, followed by Jinsung Stainless Steel, Ormco Stainless Steel, Unitek Resilient, Unitek Standard in 0.019x0.025. 2. In elongation rate, Unitek Standard showed the greatest value, followed by Ormco Stainless Steel, Unitek Hi-T, Unitek Resilient, Jinsung Stainless Steel in 0.016x0.022, and Unitek Hi-T showed the highest value, followed by Unitek Standard, Ormco Stainless Steel, Jinsung Stainless Steel, Unitek Resilient in 0.019x0.025. 3. In modulus of elasticity, Jinsung Stainless Steel showed the greatest value, followed by Unitek Hi-T, Unitek Resilient, Ormco Stainless Steel, Unitek Standard in 0.016x0.022, and Unitek Resilient showed the highest value followed by Jinsung Stainless Steel, Ormco Stainless Steel, Unitek Hi-T, Unitek Standard in 0.019x0.025. 4. In bending fatigue test, Jinsung Stainless Steel showed the greatest fracture resistance, followed by Unitek Hi-T, Unitek Standard, Unitek Resilient, Ormco Stainless Steel in 0.016x0.022, and Unitek Hi-T showed the greatest fracture resistance followed by Jinsung Stainless Steel, Unitek Resilient, Unitek Standard, Ormco Stainless Steel in 0.019x0.025. 5. In twist test, Unitek Resilient showed the greatest fracture resistance, followed by Jinsung Stainless Steel, Unitek Hi-T, Ormco Stainless Steel, Unitek Standard in 0.016x0.022, and Jinsung showed the greatest fracture resistance, followed by Unitek Resilient, Unitek Standard, Ormco Stainless Steel, Unitek Hi-T. 6. In surface topography, every products showed indentation and pitting. Jinsung stainless steel wire showed long thin indentation and relatively smooth surface. Unitek wires showed indentation and pitting and Ormco wire showed a lot of irregular pittings.
Subject(s)
Elastic Modulus , Fatigue , Hardness , Stainless Steel , Surface Properties , Tensile StrengthABSTRACT
The purpose of this study was to investigate the change of mechanical properties, surface topography and frictional force of various nickel titanium wires after recycling. Three types of nickel-titanium wires and one type of stainless steel wire were divided to three groups: as-received condition(TO:control group), treated in artificial saliva for four weeks(T1) and autoclaved after being treated in artificial saliva(T2). Some changes were observed for the selected mechanical properties in tensile test, surface topography by means of SEM and 3D profilogram, and frictional coefficient, The findings suggest that 1. Nickel-titanium wires demonstrated no statistically significant differences in maximum tensile strength, elongation rate and modulus of elasticity, but stainless steel wire demonstrated statistically significant differences in maximum tensile strength, elongation rate and modulus of elasticity between the groups(p<0.05). 2. NiTi, Optimalloy, Stainless Steel wires demonstrated increased pitting and corrosion in SEM finding. 3. Recycled NiTi, Optimalloy and stainless steel wires demonstrated significantly greater surface roughness(Ra and Rq) through 3D profilogram when compared with the control wires(p<0.05), but Sentalloy didn't demonstrate significant difference. 4. Recycled NiTi, Optimalloy and stainless steel wires demonstrated significantly greater maximum frictional coefficient when compared with the control wires(P<0.05), but Sentalloy didn't demonstrate significant difference. The changes of surface roughness and frictional coefficient in NiTi and Optimalloy had no clinical implication. Consequently recycled nickel- titanium wires demonstrated no clinical problem in tensile properties, surface topography and frictional coefficient.
Subject(s)
Alloys , Corrosion , Elastic Modulus , Friction , Nickel , Recycling , Saliva, Artificial , Stainless Steel , Surface Properties , Tensile Strength , TitaniumABSTRACT
The purpose of this study is to investigate the changes of mechanical properties and surface topography of various nickel titanium wires after heat sterilization for recycling with quantitative method. The materials used were four kinds of nickel titanium orthodontic wires including a Korean product. Experimental specimens were treated with two kinds of heat sterilization methods; dry heat (180degrees C, 60snin) and autoclave (121degrees C, 15-20psi, 30min). Mechanical properties were evaluated by tensile test with Instron 4466 (load cell capacity : 1000 kg, cross head speed : 5mm/min, grip distance : 40mm, in room temperature). Surface topography of various wires was compared with each other qualitatively by using scanning electron microscopy and quantitatively by using profilometer. The findings were analyzed statistically with student t-tests. The results were as follows; 1. Neither method of heat sterilization hod any effects on tensile properties of the nickel-titanium wires used in this experiment. 2. Before heat sterilization, the surface smoothness was highest in Optimalloy, followed by Align and Sentailoy, with NiTi showing the lowest smoothness value. 3. In surface topography, Align and Optimalloy were not influenced by heat sterilization. NiTi, on the other hand, had increased roughness after dry heat sterilization and Sentalloy showed the same tendency after each of the two heat sterilization procedures.