Orthodontic brackets

Mizrahi, E. Smith, D. C. (1969a). Direct cementation of orthodontic brackets... 

Acid etching pretreatment of enamel, such as the use of buffered 50% phosphoric acid solutions, has found clinical applications to bond enamel to restorative materials, sealants and orthodontic brackets (4, ). The etching creates an increased enamel surface area and opens pores into which the resin can flow. Greater porosity of the substrate allows an easier ingress of un-... 

Composite materials are widely used in dentistry, mainly for tooth repair, but also for bonding orthodontic brackets. The range of components that can be used is restricted by a number of considerations, including the need to match the appearance (colour and translucency) of the natural tooth, and the need to restrict the substances used to those which are non-toxic. It is also important to use materials having appropriate mechanical properties. Current materials are described in this chapter, with information on their clinical applications and performance. Some information is also included on recent developments in these materials and these may affect their clinical use in the future. 

Adult orthodontics is recently gaining popularity due to its importance in esthetics, oral, and general health [182]. However, none of the currently available alumina- or zirconia-based ceramic orthodontic brackets meet the esthetic... 

The transparent samples were characterized in terms of chemical composition, phase composition, density, hardness, flexural strength, fracture toughness, and optical transmission. Biocompatibility was evaluated with in vitro cell line experiments for cytotoxicity, apoptosis, and genotoxicity. Experimental results indicated that the transparent spinel samples exhibited promising physico-chemical, mechanical, optical properties, and excellent biocompatibility for applications as orthodontic brackets. A piece of the transparent ceramics is shown in Fig. 10.35, together with some tooth samples [182]. 

Krishnan M, Tiwari B, Seema S, Kaha N, Biswas P, Rajeswari K et al (2014) Transparent magnesium aluminate spinel a prospective biomaterial for esthetic orthodontic brackets. J Mater Sci Mater Med 25 2591-2599... 

Polymethyl methacrylate is also used as a model for dentures and stainless steel as a model for orthodontic brackets. ... 

Another application of dental composites is orthodontic archwires. One example is a unidirectional pultruded S2-glass-reinforced dimethacrylate thermoset resin. Depending on the yam of glass fiber used, the fiber volume fraction varied from 32 to 74 percent The strength and modulus were comparable with those of titanium wires. Orthodontic brackets were also made from composites with a polyethylene matrix reinforced with ceramic hydroxyapatite particles, resulting in isotropic properties and good adhesion to enamel. 

Glucose meter Balloon catheter Orthodontic bracket aligner Administration kit for peritoneal dialysis Permanent pacemaker electrode Implantable spinal cord simulator Intravascular catheter Infusion pump Urological catheter... 

Ceramic restoratives are often bonded directly to the tooth surface with adhesive resins, reducing the amount of healthy tooth reduction needed in clinical treatment. Resin-bonded fixed partial denture or resin-bonded ceramic restoration methods are often employed. Adhesive resins are also used for bonding orthodontic brackets, amalgam restoratives, and many other metal and ceramic materials. 

Glass-ionomers, by contrast, are themselves hydrophilic and inherently adhesive to the tooth surface. It therefore requires only slight pretreatment, typically conditioning with 10% aqueous polyacrylic acid. Glass-ionomers rapidly form durable bonds to the tooth surface through the development of an ion-exchange layer at the interface. This ability to bond is exploited in both the Atraumatic Restorative Treatment (ART) technique and in bonding of orthodontic brackets, both of which are described in detail in the chapter. 

Zinc polycarboxylate cements rapidly found use in clinical restorative dentistry. Applications included cavity lining, luting of crowns, and adhesion of orthodontic brackets (see O Sect. 56.14). They remain in use for these applications, but have been displaced to an extent by glass-ionomer cements. 

The earliest attempts to bond orthodontic brackets used epoxy resins. However, these adhesives were difficult to use, and so this approach did not find much support within the dental profession. In modem orthodontic practice, bonding agents similar to those used in other parts of dentistry are used. This means the deployment of either bonded composite resins or glass-ionomer cements. 

Direct bonding of orthodontic brackets uses the acid-etch technique, with phosphoric acid gel to etch the surface and deliver the initial pretreatment (Kitayama et al. 2007). This is followed by the application of bonding agents or of lightly filled or completely unfilled resins to the surface. These form attachments to the surface mechanically by flowing into the irregularities created in the etching step. 

Charles C (1998) Bonding orthodontic brackets with glass-ionomer cement. Biomaterials 19 589 De Munk J, Van Landuyt K, Penmans M, Poitevin A, Lambrechts P, Braem M, Van Meerbeck B (2005) A critical review of the durability of adhesion to tooth tissue methods and results. J Dent Res 118 132 Dunn JR (2003) iBond the seventh generation, one-bottle dental bonding agent. Compen Cont Dental Educ 24(Suppl 2) 14... 

There are numerous orthodontic appliances or devices that are used to correct dental conditions in minor and adult patients. Most of these appliances involve the use of adhesives. The advent of adhesive dentistry and direct bonding of orthodontic brackets is a dramatic event that has changed the course of clinical orthodontics. Product development and technological advances have occurred quite rapidly. This rapidity has, at times, complicated the decisionmaking process for practitioners. ... 

An extension of the use of self or light curing fissure sealant compositions developed for enamel defects, is the application to cements for the attachment of orthodontic brackets to etched enamel (Fig. 12). This use has proven quite satisfactory. 

Orthodontic brackets bonded to tooth enamel with UV cured acrylic cement after a phosphoric acid etch. 

Until recently, only long wave ultraviolet light curing systems (320 - 400 nm) were used. The first of these was a pit and fissure sealant which was reported in 1970 (1). This was followed by a composite restorative in 1973 (2). Shortly thereafter, this material was slightly modified for use as an orthodontic bracket adhesive. 

Bonding of Clear Plastic Orthodontic Brackets Using an Ultraviolet-Sensitive Adhesive", M. E. Cohl, L. J. Green, and J. D. 

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