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A Review on Biomaterials in Dental Implantology

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A Review on Biomaterials in Dental Implantology INTERNATIONAL JOURNAL of BIOMEDICAL SCIENCE REVIEW ARTICLE A Review on Biomaterials in Dental Implantology Hariprasad Ananth1, Vinaya Kundapur1, H. S. Mohammed1, M. Anand1, G. S. Amarnath1, Sunil Mankar2 1Department of Prosthodontics, MR Ambedkar Dental College, Bangalore, India; 2Department of Endodontics, DA Pandu Memorial RV Dental College, Bangalore, India ABSTRACT Implants have been gaining popularity amongst the patients and frequently are being considered as a first treatment option. Modern dentistry is beginning to understand, realize, and utilize the benefits of biotech- nology in health care. Study of material sciences along with the biomechanical sciences provides optimiza- tion of design and material concepts for surgical implants. Biocompatibility is property of implant material to show favorable response in given biological environment. In attempt to replace a missing tooth many bio- materials have been evolved as implants for many years in an effort to create an optimal interaction between the body and the implanted material. With all the advancements and developments in the science and tech- nology, the materials available for dental implants also improved. The choice of material for a particular implant application will generally be a compromise to meet many different required properties. There is, however, one aspect that is always of prime importance that how the tissue at the implant site responds to the biochemical disturbance that a foreign material presents. (Int J Biomed Sci 2015; 11 (3): 113-120) Keywords: Titanium; Osteointegration; Zirconia; Sandblasting; Bioglass; Hydroxyapetite INTRODUCTION surface topography, chemistry, energy and charge as well as bulk material composition. Schmidt et al. (2001) defines The development and modification of dental implants an ideal bone implant material as having a biocompatible have taken place for many years in an effort to create an chemical composition to avoid adverse tissue reaction, ex- optimal interaction between the body and the implanted cellent corrosion resistance in the physiologic limits, ac- material. The goal of achieving an optimal bone-implant ceptable strength, a high resistance to wear and a modulus interface has been approached by the alteration of implant of elasticity similar to that of bone to minimize bone re- sorption around the implant (1). The choice of material for a particular implant applica- tion will generally be a compromise to meet many differ- Corresponding author: Vinaya Kundapur, Senior Lecturer, Depart- ent required properties. There is, however, one aspect that ment of Prosthodontics, MR Ambedkar Dental College, Bangalore, India. is always of prime importance that how the tissue at the E-mail: [email protected]. Received July 11, 2015; Accepted September 8, 2015 implant site responds to the biochemical disturbance that Copyright: © 2015 Hariprasad Ananth et al. This is an open-access ar- a foreign material presents. Dr. Jonathan Black suggested ticle distributed under the terms of the Creative Commons Attribution that the term “biologic performance” is more appropriate License (http://creativecommons.org/licenses/by/2.5/), which permits un- restricted use, distribution, and reproduction in any medium, provided than biocompatibility to represent the various interactions the original author and source are credited. between host and the material (2). www.ijbs.org Int J Biomed Sci Vol. 11 No. 3 September 2015 113 IMPLANT BIOMATERIALS Biocompatibility is dependent on the basic bulk and size gold implant were placed without a crown to heal surface properties of the biomaterial. All aspects of ba- passively in a fresh extraction site just above the gingi- sic manufacturing, finishing, packaging and delivering, val (that were not truly submerged into bone). The crown sterilizing, and placing (including surgical) must be ad- was added after healing. The insertion of such roots of equately controlled to ensure clean and non traumatizing gold was in exitable followed by intense pain and gingi- conditions. val inflammation (5). Harris followed in 1887 with the implantation of a plat- HISTORIC BACKGROUND inum post coated with lead. The post was shaped like a tooth root and the lead was roughened for retention in the Implant designs are traceable to early Egyptians and socket (5). Bonwell in 1895 used gold and iridium tubes South Central American cultures and have evolved into implanted into bone to restore a single tooth as to sup- the present implant designs that are now experiencing ex- port complete dentures. Payne, in 1898 implanted a silver plosive popularity. The earliest dental implants were of capsule as a foundation for a porcelain crown that was ce- stone and ivory cited in archeological records of China mented several weeks later. Scholl in 1905 demonstrated and Egypt before the Common Era. Gold and Ivory dental a porcelain corrugated root implant. The implant was suc- implant were used in the 16th & 17th centuries. Metal im- cessful for two years and was anchored to adjacent teeth plant devices of Gold, Lead Iridium, Tantalum, Stainless and fillings through the use of pins (5). Steel and Cobalt alloys were developed in the early 20th Pure metallic titanium (99.9%) was first prepared in century (3). 1910 by Matthew A. Hunter by heating TiCl4 with sodium Ancient Egyptians in 2500 B.C. attempted to stabi- in a steel bomb at 700–800°C in the Hunter process.In1932 lize periodontally compromised teeth with the use of gold William Justin Kroll produced Titanium by reducing tita- ligature wire. Implanted animal teeth carved of ivory cited nium tetrachloride (TiCl4) with calcium. Eight years later in ancient Egyptian writings are the oldest examples of he refined this process by using magnesium and even so- primitive implantology. Dating to approximately 500 B.C. dium in what became known as the Kroll process (8). the Etruscan population utilized soldered golden bands in- Greenfields in 1913 introduced & patented hollow corporating animal teeth to restore masticatory efficiency. ‘basket’ implant made of mesh work of 24 gauge iridium- The Phoenician population in the same era utilized gold platinum wires soldered with 24 karat gold. This was used wire to stabilize periodontally compromised teeth (4). to support single implant as well as fixed dental prosthesis Sea shells were used in place of teeth in 600 AD evi- comprising as many as eight implants (5). dence of which was found in Honduras, & tooth restora- After 1925 modern era started with advancement in tions made of Jade & Turquoise, were found in Mayan implant biomaterials. In 1937 Venable et al analyzed the skulls. Albucasis de Condue (936-1013) of france used ox interactions of cobalt alloy & other available metals and bone to replace missing teeth; this was one of the early alloys with bone. They concluded that certain metals pro- documented placement of implant. In 1700’s John Hunter duced a galvanic reaction, which led to corrosion when suggested the possibility of transplanting teeth of one hu- these metals contacted tissue fluids. Strock in 1939 de- man to another. Towards the 18th century, Pierre Fauchard scribed a method of placing a vitallium screw to provide and John Hunter further documented tooth transportation anchorage for placement of a missing tooth. Vitallium,a with conditions for its success. They claimed that success cast alloy composed of cobalt ,chromium & molybdenum was greater with anterior teeth or premolar replacement was considered to be relatively inert, compactible with and in young people with healthy tooth sockets (5). living tissues and resistant to adverse reaction with body Titanium Sometimes called the “space age metal”. It fluids. Early evaluations documented vitallium implant was discovered in england by William Gregor in 1791 & with survival rates of 10 or more years. Vitallium has also Named by Martin Heinrich Klaproth for Titans of greek been used in different forms of surgical devices, such as mythology in 1795. Impure titanium was prepared by Nil- dental subperiosteal implant & orthopedic plates, screws, son and Pettersson in 1887 (6). nails & joints (5). Zirconium dioxide (Zro2) was accidentally identified by Formiggni in 1947 developed a single helix wire spiral the German chemist Martin Heinrich Klaproth in 1789 (7). implant made from tantalum or stainless steel. At the same In 1809, Maggiolo fabricated gold roots that were time, Raphael Chercheve designed a double delinked spiral fixed to teeth by means of a spring. These single, tooth implants made of a chrome-cobalt alloy. In 1948 Goldberg 114 September 2015 Vol. 11 No. 3 Int J Biomed Sci www.ijbs.org IMPLANT BIOMATERIALS & Gershkoff reported insertion of first viable subperios- cess. Instead of being smooth or machined, they are gen- teal implant. In 1952 Branemark developed a threaded erally roughened by sandblasting and acid etching, which implant design made of pure titanium that increased the dramatically increases the surface area to which bone can popularity of implants to new levels. Branemark studied attach. every aspect of implant design, including biological, me- chanical, physiological & functional phenomena relative TYPES OF BIOMATERIALS to success of endosteal implant. A very important aspect of this evolution-which including biomaterials, designs Dental Implant Materials & clinical application-was the clinical research led by P Metals and Alloys (Titanium & Titanium –6 Alumi- I Branemark in Sweden. His studies utilized unalloyed ti- num-4Vanadium (Ti-6AI- 4V)
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