Dental prostheses

Besides the previously mentioned collagen, a wide variety of natural polymers have been involved in the synthesis of bio-nanohybrid materials with potential application in bone repair and dental prostheses. For instance, some recent examples refer to bionanocomposites based on the combination of HAP with alginate [96,97], chitosan [98,99], bovine serum albumin (BSA) [100], sodium caseinate [101], hyaluronic acid [102], silk fibroin [103,104], silk sericin [105], or polylactic add (PLA) [106,107]. These examples illustrate the increasing interest in the subject of HAP-based biohybrid materials, which has led to almost 400 articles appeared in scientific journals in 2006 alone. 

T Vispersions of acrylic polymer beads in rapidly polymerizable liquids are important biomaterials (I, 2). The biocompatibility and functionality of dental restoratives, dental prostheses, and surgical prostheses depend on the mechanical properties of these biopolymers as well as on their physical and chemical constitution. This investigation was part of a continuing program to determine the influence of microstructural parameters on the mechanical properties of these multiphase systems. The effects of the volume fractions of dispersed phase and matrix, molecular weight of the matrix, chain length and concentration of crosslinkers, impact modifiers, and filler were studied in terms of microstructure, hard-... 

Over the eons there have been many materials, from sea shells to spices, that have been used as a medium of exchange, but the most popular have been materials that are durable and gain as much value from their scarcity as their utility. Gold is an example of the latter, as well as gemstones, in particular, diamonds. The durability of gold, its resistance to corrosion, has contributed to its usefulness for applications such as dental prostheses and electrical contacts. Likewise, the durability of diamonds has con-... 

Benzoyl peroxide is an antimicrobial and keratolytic agent used in the treatment of acne it is also added to some foods. It is a catalyst for cross-linking in the production of plastics and is occasionally used in acrylic resin systems (for example composite dental fillings, dental prostheses) in which it is formed during the cross-linking process. 

Dejobert Y, Piette F, Thomas P. Contact dermatitis from benzoyl peroxide in dental prostheses. Contact Dermatitis 2002 46(3) 177-8. 

Comments poly(methyl methacrylate) has been used as a material for intraocular lenses, for denture bases, and as a cement for dental prostheses. 

Pjetursson BE et al (2007) Comparison of survival and complication rates of tooth-supported fixed dental prostheses (FDPs) and implant-supported FDPs and single crowns (SCs). Clin Oral Implants Res 18(Suppl 3) 97-113... 

This chapter addresses the application of polymeric biomaterials in the context of implantable devices intended for long-term functionality and permanent existence in the recipients. Basic concepts of biocompatibility as well as mechanical and structural compatibility are discussed to provide appropriate background for the understanding of polymer usage in cardiovascular, orthopedic, ophthalmologic, and dental prostheses. Furthermore, emerging classes... 

The materials selected for dental prostheses mnst resemble the physical, mechanical, and aesthetic characteristics of natural teeth [54], PMMA polymers constitute the most frequently nsed group of materials in dentistry. These materials are easily adapted to specific prosthetic pnrposes while exhibiting excellent biocompatibility. In addition to... 

Initially superalloys were developed for high temperature applications. However, their field of application continues to expand and now covers areas such as cryogenic temperature appliances and orthopaedic and dental prostheses. In general, superalloys are mainly used in aircraft and industrial gas turbines, in nuclear reactors, in aircraft and spacecraft structures, in petrochemical production and in medical applications. 

Skin A 23-year-old woman, who was allergic to penicilhn, developed erythematous, fissured, scaly, pruritic lesions on the backs of the fingers and both hands after working as a prosthodontist for 1 month [77" ]. Patch testing was positive only with manganese, which is used in the manufacture of dental prostheses as a nickel substitute. 

Table 3. Identified chemicals in dental prostheses according to gas chromatographic analysis. The data have been compared with the information given in the material safety data sheets (MSDS)...

Many materials used in dentistry contain nickel, such as orthodontic wires, dental prostheses and dental casting alloys. In most instances this does not seem to cause adverse effects in nickel-sensitive individuals (Hensten-Pettersen 1989). The possibility of induction of tolerance in non-sensitised individuals by oral nickel exposure, as in orthodontic treatment, has been proposed (van Hoogstraten et al. 1991,1992). The clinical significance of this possibility is, however, not known. 

As known from other fields of (meth)acrylate use (dental prostheses, daily plastic wear), allergy can only be initiated and elicited by uncured monomers. In contrast to plastic wear, monomers are always available when using glues. So the rate of sensitisation could be rather high and similar to that of momomeric acrylate use in other occupational fields, such as dentistry. There is, however, only scanty data about real incidence of acrylate sensitivity caused by acrylic adhesives or glues in occupationally exposed individuals or even those within the normal population. 

Dental fields of application of methacrylates are, among others, dental prostheses, composite resins and primers. Methacrylic plastics are formed by polymerization of chemically highly reactive methacrylic monomers. For dental applications, it is most common to use a powder of pre-polymerized (meth)acrylates, which has to be mixed with the right amount of liquid methacrylic monomers. Depending on the polymer-... 

Kanerva L, Estlander T, Jolanki R, Tarvainen K (1993a) Occupational allergic contact dermatitis caused by exposure to acrylates during work with dental prostheses. Contact Dermatitis 28 268-275... 

Daecke C, Schaller J, Goos M (1994) Acrylates as potent allergens in occupational and domestic exposures. Contact Dermatitis 30 190-191 (Not occupational) Kanerva L, Estlander T, Jolanki R, Tarvainen K (1993) Occupational allergic contact dermatitis caused by exposure to acrylates during work with dental prostheses. Contact Dermatitis 28 268-275 Rustemeyer T, Frosch PJ (1996) Occupational skin diseases in dental laboratory technicians. (I). Clinical picture and causative factors. Contact Dermatitis 34 125-133... 

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