Download or read book Microtomographic Evaluation of a New Implant Surface in a Challenging Bone Model Study in Rabbit written by Bruna Ghiraldini and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Background: Surface characteristics of dental implants, such as roughness and chemistry, have a direct influence on bone response. Previous studies have shown that changes in implant microtopography may increase in vivo bone-to-implant contact and lead to improved bone anchorage. Sinus lift procedure is a safe and predictable method to gain bone height for implant placement. Diverse bone substitutes have been used for sinus lifting, with results comparable to those achieved when using autogenous bone.Aim: To micro-tomographically evaluate, in a challenging bone model (sinus lift procedure with anorganic bovine bone and immediate implant placement), the biologic response to a new implant surface, modified by the addition of nano-hydroxyapatite, comparing it to a double acid etched implant surface.Material and Methods: Sinus lifting procedures were performed bilaterally in 8 rabbits. Bone windows were prepared using a trephine bur, Then, the sinus mucosa was elevated, and the implant sites were prepared 3 mm mesially to the windows. Before placing the mini-implants, anorganic bovine bone grafts were inserted into both sinuses. After that, mini implants were randomly installed in prepared sites: in one sinus, double acid etched surface (DAA group); in the other, nano-hydroxyapatite surface (NHA group) implant. Collagen membranes were positioned over the windows and flaps were sutured. The rabbits were euthanized 4 weeks after surgery and biopsies were collected for analysis. Tomographic Tridimensional Bone to Implant Contact (IS/TS), Bone Volume Fraction (BV/TV), Trabecular Thickness (Tb.Th), Trabecular Number (Tb.N), and Total Porosity (To.po) were evaluated in the bone between and outside (adjacent bone) implant threads. Intra and Inter-groups differences were assessed by Student's t-test (p0.05). Results: Healing was uneventfully for all animals. After 4 weeks, for the bone analysis inside the threads, IS/TS for double acid etched and nano-hydroxyapatite implants showed comparable results, with mean values of 9,95 u00b1 0,17% vs. 10,01 u00b1 0,10% (p 0.05), respectively; the mean values of Total Bone Porosity was 75,77 u00b1 3,47% for NHA and 76,74 u00b1 3,08% for DAA (p > 0.05); for BV/TV, mean values were 24,23 u00b1 3,17% for NHA group and 23,26 u00b1 3,08% for DAA group (p> 0.05); for Tb.Th, there were not significant differences between NHA (0,060 u00b1 0,003mm) versus DAA groups (0,061 u00b1 0,004mm); for Tb.N, NHA group mean was 3.80 u00b1 0.43 and DAA group mean was 3.74 u00b1 0.39, without statistically significant differences (p>0.05). Bone analysis for outside the threads also showed no statistically significant differences between groups for all parameters, and no intra-group (inside versus outsite thread bone evaluation) statistically significant differences were observed (p>0.05 for all parameters).Conclusion and Clinical implications: It was concluded, in this pilot study assessing early implant evaluation in a challenging bone model, that micro-tomographical bone parameters were similar both for double acid etched and nano-hydroxyapatite surface implants. Further studies analyzing longer healing times and with histomorphometric evaluation are suggested.

Download or read book Microtomographic Evaluation of a Nanometric Implant Surface Associated to L PRF Study in Osteoporotic Rats written by and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Background: Osteoporosis is associated to decrease of bone mineral density, leading to an increase of skeletal frailty and fracture risk. Surface characteristics of dental implants may influence bone response, modulating cell proliferation and differentiation. Nanostructures applied to biomaterials may contribute to a higher bone to implant contact. Previous studies have shown that Leukocyte platelet rich fibrin (L-PRF) can increase the amount and formation rate of new bone around implants.Aim: To micro-tomographically evaluate, in osteoporotic rats, the bone repair around two implant surfaces, associated of not to L-PRF, analyzing Bone to Implant Contact (IS/TS,%), Bone Volume Fraction (BV/TV,%), Bone Surface/Volume (BS/BV,%) Trabecular Thickness (Tb.Th,mm), and Total Porosity (To.Po,%).Material and methods: Mini implants with 2 types of surface (double acid etched=DAE, or with the addition of nano-hydroxyapatite = NHA; 24 implants of each type) were installed in the tibias of osteoporotic rats. In 24 rats, L-PRF was obtained with blood collection by means of cardiac puncture and posterior centrifugation, and inserted in the prepared bone site before implant insertion. The 48 rats were randomly divided into 4 experimental groups of 12 rats each: G1- DAE implants installed; G2- NHA implants installed; G3- DAE implants installed in association to L-PRF; G4- NHA implants installed in association to L-PRF. All the mini implants were prepared for the study, measured 2.7mm in length x 1.4mm in diameter, and had the same macrostructure. The animals were euthanized 7 and 30 days (7d and 30d) after implants placement (6 from each group/period). The tibias were removed for microtomographic evaluation of the bone between the threads of the implants, analyzing the previously described parameters.Results: Inter-groups differences were assessed using One-way Analysis of Variance (p

Download or read book Evaluation of a Nanohydroxyapatite Covered Implant Surface Study in Rats Exposed to Cigarette Smoke written by Scombatti De Sergio and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Background: Modifications on titanium implants (changes in design, in surface and addition of biological compounds) may improve the bone to implant contact. Previous studies have shown that the addition of nanohydroxyapatite to the implant surface may contributing to the acceleration of bone healing. Smoking is a challenging situation, negatively affecting the osseointegration process: nicotin reduces osteogenic activity, increases periodontal and periimplant bone loss and may lead to implant failure. Aim: The purpose of this study was to evaluate, in rats exposed to cigarette smoke (as a model of deficient bone repair), a new implant surface modified by the addition of nanohydroxyapatite, through microtomographic analysis.Material and methods: Mini implants (machined, double acid etched and nanohydroxyapatite surfaces) were installed in the tibias of rats submitted to cigarette smoke inhalation (n=36). The animals were randomly divided into three experimental groups of twelve rats each: G1(MA), machined implants; G2(AE), acid etched implants; and G3(NH), nanohydroxyapatite covered implants. The animals were sacrified 7 (7d) and 30 (30d) days after implants placement (18 animals by period, 6 from each group). The tibias were removed for evaluation. Microtomographic Bone to Implant Contact (IS/TS, in %), Bone Volume Fraction (BV/TV, in %), Trabecular Number (Tb.N) and Thabecular Thickness (Tb.Th) were measured. These parameters evaluated the bone characteristics between the threads and outside the threads (adjacente bone). Inter-group differences were assessed by ANOVA + Tukey tests; intra-group diferences (between threads bone vs. adjacent bone) was analized by the Mann-Whitney test (for all comparisons p

Download or read book Histomorphometric Evaluation of Two Implant Surfaces in Cortical and Grafted Bone Study in Rabbits written by Marcos de Invernici and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface topography of dental implants, implant loading protocols, surgical technique and implant design can affect the bone response. Nanoscale surface modifications have been shown to increase in vivo bone-to-implant contact and lead to improved bone anchorage. Sinus lift procedure is a safe and predictable method to gain bone height for implant placement. Different bone substitutes have been used for sinus lifting, with results comparable to those achieved when using autogenous bone. The aim of this study was to analyze, in rabbits, the bone response to two different implants surfaces installed after sinus lift procedures, evaluating histomorphometric parameters (bone to implant contact= BIC, and bone area fraction occupancy= BAFO) on the cortical bone and the grafted area. Sinus lifting procedures were performed bilaterally in 16 rabbits. Bone windows were prepared using a trephine bur. Then, the sinus mucosa was elevated, and the implant sites were prepared 3 mm mesially to the windows. Before placing the mini-implants, anorganic bovine bone grafts were inserted into both sinuses. After that, mini implants were randomly installed in prepared sites: in one sinus, double acid etched surface (DAA group); in the other, nano-hydroxyapatite surface (NHA group) implant. Collagen membranes were positioned over the windows and flaps were sutured. The rabbits were euthanized 4 and 8 weeks after surgery (8 animals each time) and biopsies were collected for analysis. Data were assessed through analysis of variance + Tukey test and are presented as a function of mean and 95% confidence interval. BIC (in %) and BAFO (in %) were evaluated in the cortical bone and in the grafted bone. After 4 weeks, for the cortical bone, mean values of BIC were 92.60 u00b1 4.50 for DAA vs. 88.33 u00b1 5.26 for NHA (p > 0.05); the mean values of BAFO were 93.01 u00b1 2.71 for NHA and 83.30 u00b1 7.00 for DAA (p 0.05); for the grafted bone, mean values of BIC were 19.81 u00b1 9.82 for DAA vs. 56.00 u00b1 14.06 for NHA (p 0.05); the mean values of BAFO were 45.81 u00b1 8.83 for NHA and 22.59 u00b1 7.95 for DAA (p 0.05). After 8 weeks, for cortical bone, mean values of BIC for DAA and NHA implants were 85.34u00b18.29 vs. 86.01 u00b1 6.47 (p 0.05), respectively; the mean values of BAFO were 86.92u00b18.85 for NHA and 84.13 u00b1 6.56 for DAA (p 0.05); for the grafted bone, mean values of BIC were 43.72 u00b1 14.93 vs. 63.67 u00b1 10.79 (p

Download or read book Comparative Study of a Chemically Enhanced Implant Surface Osseotite and a Machined Titanium Implant Surface in Suprabony Augmentation Using Autogenous Bone Graft a Study in the Rabbit Femur written by Afshin Salamati and published by . This book was released on 2000 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of a Novel Self assembled Nanocoating in Promoting Bone On growth and Apposition on Metal written by Hani Ghazi and published by . This book was released on 2011 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: Loosening of metal is the leading cause of clinical failures of orthopedic surgeries. A novel coating of self-assembled monolayer of phosphonate molecules (SAMP) that chemically enhances metallic surfaces by covalently bonding to their naturally occurring oxidized surfaces has been developed.1 The SAMP coating is chemically stable, and its in-vitro results showed that it promotes cell proliferation, osteoblast adhesion and enhances biological attachment to metal surfaces.1 The purpose of this study is to establish the efficacy of this novel chemical surface treatment in improving the fixation of metallic implants in both cortical and cancellous bone over a conventional untreated implant. We hypothesize that a SAMP monolayer coating would lead to greater in-vivo bone on-growth and fixation of SAMP-coated stainless steel (SS) implants when compared against uncoated ones. An established in-vivo model was used. The outcomes used to establish the coating's efficacy were the histological appearance of the interface between implant and bone and the static mechanical strength of the interface. Cylindrical 316L SS implants were machined and highly polished and half of the implants were coated with the SAMP coating. A total of 44 male, skeletally mature New Zealand White rabbits, weighing between 3.5 and 5kg, were implanted bilaterally in the distal femoral intramedullary canals. Each animal received one coated implant in one leg and one uncoated implant in the other leg. Cylindrical implants were implanted in 9 rabbits per time point. Additionally at each time-point, 2 rabbits were implanted with cylindrical pins that have 6 longitudinal crevices and their cross-section were circumferentially serrated. The rabbits were randomized to one of four time points: 4, 8, 12 and 16 weeks. In the cylindrical implants, bone formation was evident in the epiphyseal cancellous bone surrounding the coated implants after 4 weeks. Histological evaluation of early time points has showed cell types associated with new bone formation, in both the cortical and cancellous 5 bone, in higher numbers in the treated implants. A thicker layer of unmineralized osteoid and higher number of osteoblasts were observed along the interfaces with the coated surfaces than the uncoated ones in the 4-week time-point. That indicated that there is greater bone formation and a stronger initial bone response to the coating. At the later time points, however, there was no difference between the amount of bone formed around the coated implants and the uncoated ones. At the 4-week time point, the coated samples of the creviced design showed significant osteoconductive potential of the treatment, which was observed histologically as recruitment and proliferation of osteoblasts into areas of initially non-bony contact are present. Bone had formed completely into the interior crevices of the coated implants. In the uncoated implants, bone was only present in the outer area surrounding the implants. Micro-Computed Topography scanning was performed on all the cancellous bone samples in order to visualize the amount of newly formed bone around the implants and calculate bone volume to total volume within the relative effective diameter. In the early time points, it was found that bone has grown in a larger volume around the coated implants. No statistical difference in bone volume was found at the later time points. Mechanical pullout testing was performed on cylindrical implants at each time-point (n=6) of the coated and uncoated implants. A mechanical pullout apparatus that ensures pullout in a uniaxial direction at under displacement control was used, and the resistive shear force at failure was measured. Mechanical testing showed no difference in the average of failure force of the coated group when compared to that of the uncoated group at each time point. There was also no statistical difference between time points among the coated samples. The SAMP coating did not increase the shear strength of the interface. In conclusion, in a rigorous, established model, we have shown that at early time points, the SAMP treatment elicits a significant bony apposition to the implant surface. However, this effect does not appear to be maintained.

Download or read book Modelling and Characterization of Mechanically Regulated Tissue Formation Around Bone interfacing Implants written by Craig Alexander Simmons and published by . This book was released on 2000 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In many cases, orthopaedic and dental implants can restore function to diseased or damaged joints and edentulous jaws. However, in several challenging clinical situations, it is difficult to achieve adequate fixation (osseointegration) between the implant and bone. Since osseointegration is necessary for clinical success, implant failure rates in these cases are unacceptably high. Understanding the factors that allow bone-interfacing implants to osseointegrate rapidly and reliably should lead to improvements in their use and design. With this being our goal, we investigated the influence of implant surface geometry and local tissue strains on peri-implant tissue formation. Using a rabbit model, we evaluated the histological and mechanical characteristics of the early healing tissues around nonfunctional implants with Ti6Al4V sintered porous surfaces and Ti plasma-sprayed surfaces. We found that the early healing tissues integrated with the three-dimensional interconnected structure of the sintered porous surface and mineralized more rapidly than the tissues around the irregular geometry of the plasma-sprayed surface. Consequently, the stiffness and strength of attachment was greater for the porous-surfaced implants. These results demonstrate that implant surface geometry influences early peri-implant tissue formation and, as a result, the early mechanical stability of implants. To investigate the relationship between implant surface geometry, the local mechanical environment, and peri-implant tissue formation, we developed a computational micromechanical model based on homogenization methods to describe the effective and local properties of the porous-surfaced and plasma-sprayed peri-implant regions. In validation tests, we showed that the model provided reasonably accurate initial predictions of the properties of the peri-implant regions. Using the computational model, we compared the local mechanical environments around porous-surfaced and plasma-sprayed implants. In cases with minimal implant loading, the model predicted local tissue strains that permitted localized ' and' appositional bone formation around porous-surfaced implants, but only appositional bone formation for plasma-sprayed implants. Based on the model predictions and experimental data from earlier studies, we proposed a quantitative model for the mechanical regulation of peri-implant tissue formation. The mechanoregulatory model is consistent with observations of tissue formation around porous-surfaced and plasma-sprayed implants, and provides initial criteria to evaluate the osseointegration potential of bone-interfacing implants.

Download or read book Bone Implant Interface written by Hugh U. Cameron and published by St. Louis ; Toronto : Moseby. This book was released on 1994 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Strontium and Strontium Compounds written by Peter Watts and published by World Health Organization. This book was released on 2010-06-07 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: "IPCS, International Programme on Chemical Safety"--Cover.

Download or read book Calcium Orthophosphates written by Sergey V. Dorozhkin and published by CRC Press. This book was released on 2012-06-04 with total page 863 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to a great chemical similarity with the biological calcified tissues, many calcium orthophosphates possess remarkable biocompatibility and bioactivity. Materials scientists use this property extensively to construct artificial bone grafts that are either entirely made of or only surface-coated with the biologically relevant calcium orthophospha

Download or read book Functional Tissue Engineering written by Farshid Guilak and published by Springer Science & Business Media. This book was released on 2003-07-09 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: -Softcover reprint of a successful hardcover reference (370 copies sold) -Price to be accessible to the rapidly increasing population of students and investigators in the field of tissue engineering -Chapters written by well-known researchers discuss issues in functional tissue engineering as well as provide guidelines and a summary of the current state of technology

Download or read book Micro computed Tomography micro CT in Medicine and Engineering written by Kaan Orhan and published by Springer. This book was released on 2019-07-25 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on applications of micro CT, CBCT and CT in medicine and engineering, comprehensively explaining the basic principles of these techniques in detail, and describing their increasing use in the imaging field. It particularly highlights the scanning procedure, which represents the most crucial step in micro CT, and discusses in detail the reconstruction process and the artifacts related to the scanning processes, as well as the imaging software used in analysis. Written by international experts, the book illustrates the application of micro CT in different areas, such as dentistry, medicine, tissue engineering, aerospace engineering, geology, material engineering, civil engineering and additive manufacturing. Covering different areas of application, the book is of interest not only to specialists in the respective fields, but also to broader audience of professionals working in the fields of imaging and analysis, as well as to students of the different disciplines.

Download or read book Handbook of Histology Methods for Bone and Cartilage written by Yuehuei H. An and published by Springer Science & Business Media. This book was released on 2003-05-01 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt: Histotechnology and histomorphometry are the major methodologies in bone and cartila- related research. Handbook of Histology Methods for Bone and Cartilage is an outgrowth of the editors’ own quest for information on bone and cartilage histology and histomorphometry. It is designed to be an experimental guide for personnel who work in the areas of basic and clinical bone and cartilage, orthopedic, or dental research. It is the first inclusive and organized reference book on histological and histomorphometrical techniques on bone and cartilage specimens. The topic has not previously been covered adequately by any existing books in the field. Handbook of Histology Methods for Bone and Cartilage has six major parts and is designed to be concise as well as inclusive, and more practical than theoretical. The text is simple and straightforward. Large numbers of tables, line drawings, and micro- or macro-photographs, are used to help readers better understand the content. Full bibliographies at the end of each chapter guide readers to more detailed information. A book of this length cannot discuss every method for bone and cartilage histology that has been used over the years, but it is hoped that major methods and their applications have been included.

Download or read book Hydroxyapatite HAp for Biomedical Applications written by Michael Mucalo and published by Elsevier. This book was released on 2015-03-06 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydroxyapatite in the form of hydroxycarbonate apatite is the principal mineral component of bone tissue in mammals. In Bioceramics, it is classed as a bioactive material, which means bone tissue grows directly on it when placed in apposition without intervening fibrous tissue. Hydroxyapatite is hence commonly used as bone grafts, fillers and as coatings for metal implants. This important book provides an overview of the most recent research and developments involving hydroxyapatite as a key material in medicine and its application. - Reviews the important properties of hydroxyapatite as a biomaterial - Considers a range of specific forms of the material and their advantages - Reviews a range of specific medical applications for this important material

Download or read book Bioceramics and Biocomposites written by Iulian Antoniac and published by John Wiley & Sons. This book was released on 2019-04-04 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides comprehensive coverage of the research into and clinical uses of bioceramics and biocomposites Developments related to bioceramics and biocomposites appear to be one the most dynamic areas in the field of biomaterials, with multiple applications in tissue engineering and medical devices. This book covers the basic science and engineering of bioceramics and biocomposites for applications in dentistry and orthopedics, as well as the state-of-the-art aspects of biofabrication techniques, tissue engineering, remodeling, and regeneration of bone tissue. It also provides insight into the use of bionanomaterials to create new functionalities when interfaced with biological molecules or structures. Featuring contributions from leading experts in the field, Bioceramics and Biocomposites: From Research to Use in Clinical Practice offers complete coverage of everything from extending the concept of hemopoietic and stromal niches, to the evolution of bioceramic-based scaffolds. It looks at perspectives on and trends in bioceramics in endodontics, and discusses the influence of newer biomaterials use on the structuring of the clinician’s attitude in dental practice or in orthopedic surgery. The book also covers such topics as biofabrication techniques for bioceramics and biocomposites; glass ceramics: calcium phosphate coatings; brain drug delivery bone substitutes; and much more. Presents the biggest trends in bioceramics and biocomposites relating to medical devices and tissue engineering products Systematically presents new information about bioceramics and biocomposites, developing diagnostics and improving treatments and their influence on the clinicians' approaches Describes how to use these biomaterials to create new functionalities when interfaced with biological molecules or structures Offers a range of applications in clinical practice, including bone tissue engineering, remodeling, and regeneration Delineates essential requirements for resorbable bioceramics Discusses clinical results obtained in dental and orthopedic applications Bioceramics and Biocomposites: From Research to Use in Clinical Practice is an excellent resource for biomaterials scientists and engineers, bioengineers, materials scientists, and engineers. It will also benefit mechanical engineers and biochemists who work with biomaterials scientists.

Download or read book Degradation of Implant Materials written by Noam Eliaz and published by Springer Science & Business Media. This book was released on 2012-08-21 with total page 521 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reviews the current understanding of the mechanical, chemical and biological processes that are responsible for the degradation of a variety of implant materials. All 18 chapters will be written by internationally renowned experts to address both fundamental and practical aspects of research into the field. Different failure mechanisms such as corrosion, fatigue, and wear will be reviewed, together with experimental techniques for monitoring them, either in vitro or in vivo. Procedures for implant retrieval and analysis will be presented. A variety of biomaterials (stainless steels, titanium and its alloys, nitinol, magnesium alloys, polyethylene, biodegradable polymers, silicone gel, hydrogels, calcium phosphates) and medical devices (orthopedic and dental implants, stents, heart valves, breast implants) will be analyzed in detail. The book will serve as a broad reference source for graduate students and researchers studying biomedicine, corrosion, surface science, and electrochemistry.

Download or read book Titanium in Medical and Dental Applications written by Francis Froes and published by Woodhead Publishing. This book was released on 2018-05-09 with total page 656 pages. Available in PDF, EPUB and Kindle. Book excerpt: Titanium in Medical and Dental Applications is an essential reference book for those involved in biomedical materials and advanced metals. Written by well-known experts in the field, it covers a broad array of titanium uses, including implants, instruments, devices, the manufacturing processes used to create them, their properties, corrosion resistance and various fabrication approaches. Biomedical titanium materials are a critically important part of biomaterials, especially in cases where non-metallic biomedical materials are not suited to applications, such as the case of load-bearing implants. The book also covers the use of titanium for implants in the medical and dental fields and reviews the use of titanium for medical instruments and devices. - Provides an understanding of the essential and broad applications of Titanium in both the medical and dental industries - Discusses the pathways to manufacturing titanium into critical biomedical and dental devices - Includes insights into further applications within the industry