Composite resin has been used for nearly 50 years as a restorative material in dentistry. Use of this material has recently increased as a result of consumer demands for esthetic restorations, coupled with the public's concern with mercury-containing dental amalgam. Composite is now used in over 95% of all anterior teeth direct restorations and in 50% of all posterior teeth direct restorations. Carbon fiber reinforced composites have been developed for use as dental implants. In medicine, fiber-reinforced composites have been used in orthopedics as implants, osseous screws, and bearing surfaces. In addition, hydroxyapatite composite resin has become a promising alternative to acrylic cement in stabilizing fractures and cancellous screw fixation in elderly and osteoporotic patients. The use of composite resin in dentistry and medicine will be the focus of this review, with particular attention paid to its physical properties, chemical composition, clinical applications, and biocompatibility.
Glass ionomer cements are a group of materials based on the acid/base reaction between poly(alkenoic) acid and an ion-leachable silicate glass. The material was developed in dentistry as a tooth restorative material that released fluoride ions over an extended time, bonded to tooth structure, and was very biocompatible. Its use in dentistry was initially limited by its slow setting time and lack of strength; however, modern formulations of the material have yielded materials with properties that are clinically useful in dentistry. Its biocompatibility, osteoconductive behavior, and ability to bond to bone and metals have generated interest in the material for medical applications. Glass ionomer cements in medicine have been used as bone cements, implants to replace ossicular bones of the inner ear, as well as other craniofacial implants. The early release of fluoride and aluminum ions and release of polyacids have been implicated in tissue biocompatibility in medical use. Additional material development is necessary to optimize its properties for use in medicine. This article reviews the literature written on the composition, chemistry, fluoride release, biocompatibility, and medical uses of glass ionomer cements.
The purpose of this collective review is to study the history, physical and chemical properties, application, and clinical consequences of gold implants in the dental and medical fields. Gold implants are used in various medical procedures, including reconstructive surgery of the middle ear, upper lid closure in facial nerve paresis-induced lagophthalmos, drug delivery microchips, antitumor treatment, treatment of rheumatoid arthritis, use on the surface of voice prostheses, and endovascular stents, with sound clinical results. However, in order to achieve better therapeutic benefits, clinical reports have documented that the surface of gold implants have been modified or encased in biocompatible alloplastic materials, or they have been replaced by cheaper and more biocompatible materials. Gold is also applied to a long list of dental prostheses, including inlays, onlays, crowns, bridges, periodontal splints, and post and cores. It has sufficient strength and corrosion resistance, and it is relatively biocompatible. In addition, gold dental prostheses have a long life cycle. However, esthetic concerns and cost make it a less desirable prosthesis today than in the past.
Over the past 150 years, silver-tin-copper amalgam has been the most frequently used dental restorative material. Amalgam may be the single most frequently used implant material. In the early 1980s, researchers discovered that amalgam restorations release mercury vapor during chewing. This review describes the research that has led to an estimate of the daily dose of mercury that will be absorbed by a subject with a large number of amalgam restorations. Along the way, the history and chemistry of dental amalgam are outlined. The routes of absorption of liquid mercury, ionic mercury, organic mercury, and mercury vapor are also briefly described. The daily dose is found to be 14% of the threshold above which observable adverse neurological symptoms are expected. The review concludes with a summary of the research on the adverse effects of dental amalgam. As expected from the low daily dose, few adverse neurological symptoms have been reported. There is also little evidence of an association of amalgam restorations with neurodegenerative diseases, altered renal function, adverse pregnancy outcomes, or autoimmune diseases. There is a lack of data on neurobiological and neurodevelopmental effects on children who may be exposed to mercury from maternal amalgam restorations during gestation. Additional data on the role of amalgam, if any, in Alzheimers disease and multiple sclerosis are needed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.