Aesthetic restoration

A restorative material can be used for the aesthetic restoration of the front (anterior) teeth only if it is as translucent as tooth enamel. This is because colour matching depends on translucency as well as hue and chroma. 

The glass polyalkenoate cement was originally intended as a substitute for dental silicate cements for the aesthetic restoration of front (anterior) teeth (Wilson Kent, 1972 Knibbs, Plant Pearson, 1986a Osborne Berry, 1986 Wilson McLean, 1988). It is suitable for restoring anterior cavities in low-stress situations, that is when the restoration is completely supported by surrounding tooth material. These cavities occur on the adjacent surfaces of neighbouring teeth (class III cavities) and at the gum line (class V cavities). 

Dental silicate cement was once the most favoured of all anterior (front) tooth filling materials. Indeed, it was the only material available for the important task of aesthetic restoration from the early 1900s to the mid 1950s, when the not very successful simple acrylic resins made their appearance (Phillips, 1975). In the mid sixties there were some 40 brands available (Wilson, 1969) and Wilson et al. (1972) examined some 17 of these. Since that time the use of the cement has declined sharply. It is rarely used and today only two or three major brands are on the market. The reason for this dramatic decline after some 50 years of dominance is closely linked with the coming of modern aesthetic materials the composite resin from the mid 1960s onwards (Bowen, 1962), and the glass-ionomer cement (Wilson Kent, 1971) from the mid 1970s. 

Dental silicate cement is used exclusively for the aesthetic restoration of... 

Dental silicate cement is used for the aesthetic restoration of anterior (front) teeth because it is translucent and so can be made to colour-match tooth enamel. It is prepared by introducing powder into the liquid gradually in order to dissipate heat, although the exotherm is not so great... 

B. Touati, The evolution of aesthetic restorative materials for inlays and onlays a review, Bract. Periodontics Aesthet. Dent. 8 (1996) 657-666. 

V. Arora, P. Bogra, Giomer a new hybrid aesthetic restorative material, J. Conserv. Dent. 5 (2002) 149-155. 

A.U. Yap, S.M. Chung, W.S. Chow, K.T. Tsai, C.T. Lim, Short-term fluoride release from various aesthetic restorative materials, Oper. Dent. 29 (2004) 29-34. 

Pillet, J., and Mackin, E. J. (1992). Aesthetic restoration. Chap. 7C in Atlas of Limb Prosthetics - Surgical, Prosthetic, and Rehabilitation Principles, 2d ed., Bowker, J. H., and Michael, J. W., (eds.), American Academy of Orthopaedic Surgeons (AAOS), Mosby Year Book, St Louis, Mo., pp. 227-236. 

FPDs). They often have less aesthetically pleasing restoration than FPDs coupled with the nuisance of removing them at night and a psychologically less satisfying lack-of-permanency. 

Unfilled Tooth Restorative Resins. UnfiUed reskis were some of the first polymer materials iatroduced to repak defects ki anterior teeth where aesthetics were of concern. They have been completely replaced by the fiUed composite reskis that have overcome the problems of poor color StabUity, low physical strength, high volume shrinkage, high thermal expansion, and low abrasion resistance commonly associated with unfiUed reskis. 

However, restorations made from this material could not be polished and were aesthetically very poor. Simmonds (1983) has pursued this idea, and a material has been placed on the market. But according to Moore, Swartz Phillips (1985) such cements have less resistance to abrasion than a simple glass polyalkenoate cement. 

McLean, J. W. (1980). Aesthetics in restorative dentistry the challenge for the future. British Dental Journal, 149, 368-72. 

The senior author first became interested in acid-base cements in 1964 when he undertook to examine the deficiencies of the dental silicate cement with a view to improving performance. At that time there was much concern by both dental surgeon and patient at the failure of this aesthetic material which was used to restore front teeth. Indeed, at the time, one correspondent commenting on this problem to a newspaper remarked that although mankind had solved the problem of nuclear energy the same could not be said of the restoration of front teeth. At the time it was supposed that the dental silicate cement was, as its name implied, a silicate cement which set by the formation of silica gel. Structural studies at the Laboratory of the Government Chemist (LGC) soon proved that this view was incorrect and that the cement set by formation of an amorphous aluminium phosphate salt. Thus we became aware of and intrigued by a class of materials that set by an acid-base reaction. It appeared that there was endless scope for the formulation of novel materials based on this concept. And so it proved. 

Art conservation, particularly painting restoration, is an important endeavor to preserve our cultural heritage and maintain the aesthetic value of an artistic piece. Chemical reactions occurring on a microscopic level are the origin of the macroscopic changes that we observe as ageing. 

Compomers are properly called polyacid-modified composite resins and are a group of aesthetic materials chemically similar to the well-established composite resins [266], They were introduced to the dental profession in the early 1990s [267], and were intended to combine the benefits of traditional composite resins and glass-ionomer cements, and their trivial name reflects this, being derived from the names of these two parent materials, the comp coming from composite, and omer from ionomer [268], These materials are now considered a distinct class of dental restorative, with well established uses in clinical restoration, particularly in children s dentistry [269],... 

A.J. Preston, E.A. Agalamany, S.M. Fligham, L.FI. Mair, The recharge of aesthetic dental restorative materials with fluoride in vitro—Two year results. Dent. Mater. 19 (2003) 32-37. 

Polymers used as dental materials must meet several stringent requirements. Dental restorative materials must be nontoxic, have aesthetic appearance, and good adhesive and mechanical properties. In addition, these materials must exhibit long term stability in the presence of water, enzymes, and various oral fluids, and withstand thermal and load cycles. Finally, a desirable dental restorative materia] should be convenient to work with at the time of application. 

The performance of polyelectrolyte materials is determined by several factors, including the extent to which the dental material adheres to the tooth, cario-static properties of the restoration, pulpal and tissue sensitivity in the vidnity of the restorative material, long-term stability of the dental material, and perhaps most importantly, the aesthetic appeal of the restorative material. Poor adhesion leads to the formation of gaps, which become sites for infection. Biodegradation of the cement can cause increased pulpal and oral-tissue sensitivity, as well as systemic responses. Several recent reviews on the performance of GICs [121,173,230-232] are available, so the subject is only briefly discussed here. 

With more than 200 million dental restorations performed each year, the importance of using a restorative material which is both safe and durable should not be underestimated. Currently, dental amalgam is used in the vast majority of these restorations however, recent scrutiny of mercury levels in dental amalgam and the desire for tooth colored restorations have led to increasing demand for polymeric dental composites. Polymeric composites, generally composed of a multimethacrylate and a ceramic glass filler, have primarily been used for anterior tooth restorations in which color matching is imperative for aesthetic purposes. 

Composite resins allow for color matching, conservative cavity preparation, and simple preparation through intraoral photopolymerization. These advantages have made composites an increasingly popular substitute for amalgam in dental restorations, especially when aesthetics are of concern. In this article, we will focus on the actual process of forming dental composites, the properties of the composites that are formed, and a complete description of the photopolymerization of the multimethacrylates that produce the dental composite. We will only be focusing on the use of polymers as dental restorations. Other dental applications of polymers, e.g. dentures and ionomer cements (reviewed elsewhere by Scranton and Klier) will not be addressed. 

Amalgam is aesthetically unattractive compared to new materials. It has a metallic color that does not reproduce the natural appearance of the ce-ramo-organic tooth structure. The release of metallic ions from the amalgam restoration also can discolor the neighboring tooth structure [19]. 

The demand for aesthetic dental restorative materials continues to increase and may be the most important criterion for the promising future of the aesthetic polymeric composite resins. As the physical, mechanical, and wear properties of these materials improve, their use in dentistry will expand. The acid-etching of dental enamel [20] and dentin bonding procedures [21] will allow for conservative cavity preparation and the preservation of healthy tooth structure. 

Despite many years of research and attempts to develop the ideal polymeric composite restorative material, significant problems still exist with present day composite resins. These problems are associated with the polymer itself, the polymerization reaction, the durability of the restoration, and the aesthetics of the material. 

In anterior teeth, where aesthetics is more critical to the patient ad where the restoration can be shielded from the strongest biting forces, the composite can serve as an excellent, long lasting restorative. The current mechanical properties of the material allow excellent clinical success in these applications. 

All the other metallic alloys (iron, zinc, lead, etc.) that do not form protective and/or aesthetic patina, are usually covered with paint as protection layer. Anyway, many world treasures have been moved indoors after restoration, as in the case of Marco Aurelio and the Venice Horses. 

Vellum bindings can be furbished, but apart from the aesthetic gain there is little point in it, and the time can be better spent on other things. However, some advice is given below (see p. 18). Structural restoration of vellum bindings is very much a matter for the experienced restorer, but it should be possible for those who have some experience of the craft to fasten books back into their vellum cases (see p. 12). 

Adams, E. A. "Aesthetic and Structural Restoration of an Early Twentieth... 

The decision to initiate cleanup and restoration activities on oil-contaminated shorelines is based on careful evaluation of socio-economic, aesthetic, and ecological factors. These include the behaviour of oil in shoreline regions, the types of shoreline and their sensitivity to oil spills, the assessment process, shoreline protection measures, and recommended cleanup methods. Criteria of importance to this decision are discussed in this chapter. 

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