Dental market

Most of over six million dentures produced annually in the USA are made of acrylics (PMMAs) that includes full dentures, partial dentures, teeth, denture reliners, fillings and miscellaneous uses. Plastics have been edging into the dental market for over a half century. Even before the introduction of acrylics to the dental profession in 1937, nitrocellulose, phenol-formaldehyde and vinyl plastics were used as denture base materials. Results, however, were not wholly satisfactory because these plastics did not have the proper requisites of dental plastics. Since then, PMMAs have kept their lead as the most useful dental plastics, although many new plastics have appeared and are still being tested. Predominance of PMMAs is not surprising, for they are reasonably strong, have exceptional optical properties, low water absorption and solubility, and excellent dimensional stability. Most denture base materials, therefore, contain PMMA as the main ingredient. 

The dental market in the United States shows the most sensitivity to commodity prices while the markets in Germany and Japan show the effect of government-sponsored programs. 

Other successful developments have been initiated by needs within the dental market such as the demand for a long-working dough for packing a number of denture cases with one mix. Studies of various compositions were made and the possible disadvantages were studied... 

Nonnutritive Sweeteners. Consumer desire to reduce caloric iatake and protect dental health has created an enormous market for nonnutritive sweeteners (qv). As of this writing there are only three nonnutritive sweeteners approved for use ia the United States. 

Medicine. The polymethacrylates have been used for many years in the manufacture of dentures, teeth, denture bases, and filling materials (116,117) (see Dental materials). In the orthodontics market, methacrylates have found acceptance as sealants, or pit and fissure resin sealants which are painted over teeth and act as a barrier to tooth decay. The dimensional behavior of curing bone-cement masses has been reported (118), as has the characterization of the microstmcture of a cold-cured acryUc resin (119). Polymethacrylates are used to prepare both soft and hard contact lenses (120,121). Hydrogels based on 2-hydroxyethyl methacrylate are used in soft contact lenses and other biomedical appHcations (122,123) (see Contactlenses). 

Several crystalline condensed phosphates may also be formed by the dehydration of monosodium phosphate (MSP). Maddrell s salt exists as Form 11 (high temperature MaddreU, NaPO -ll, insoluble metaphosphate-11) and Form 111 (low temperature MaddreU, NaPO -lll, insoluble metaphosphate-111). Both forms are highly polymerized and difficult (slow) to dissolve in water. Mixtures of the two forms are marketed as a dental abrasive for toothpaste formulations containing soluble fluoride. Maddrell s salt is also used with disodium phosphate as a cheese emulsifying aid. 

The total value of dental suppHes and equipment manufactured in the United States in 1992 is estimated at ca 1.2 biUion. These materials are used by ca 170,000 practicing dentists (1992) and >8, 500 commercial dental laboratories employing ca 40—50,000 technicians. The dental materials market is limited because the pubHc does not buy direcdy except for toothpastes, mouthwashes, toothbmshes, denture aids, etc (see Dentifrices). 

Regulation. Dental implants are regulated by the Food and Dmg Administration. AH dental implants faH iato the FDA class III which covers devices that are life sustaioiag, life supportiag, or are implanted iato the body and have the potential to cause unreasonable risk, illness, or iajury. Devices ia class III are requited to have appHcatioas for premarket approval (315). There are 15 to 20 companies that have FDA marketing clearance for specific dental implants, based on substantial equivalency to implants marketed prior to 1976, and approximately one third of these companies are foreign. Marketing clearance is not the same as premarket approval. 

Claims for oral dental riases are regulated by the Food and Dmg Administration whether they are marketed as dmgs or cosmetics. The Council on Dental Therapeutics of the American Dental Association reviews oral riases, and may authori2e use of the Seal of Acceptance for a product. 

The commercial possibiUties for epoxy resins were first recognized by DeTrey Emres in Switzerland and DeVoe and Raynolds in the United States (1,2). In 1936, DeTrey Emres produced a low melting bisphenol A-based epoxy resin that gave a thermoset composition with phthaUc anhydride. Apphcation of the hardened composition was foreseen in dental products, but initial attempts to market the resin were unsuccessful. The patents were hcensed to CIBA AG of Basel, Switzerland (now CIBA-GEIGY), and in 1946 the first epoxy adhesive was shown at the Swiss Industries Eair and samples of casting resin were offered to the electrical industry. 

PAEK) plastic that cost 40/lb was being market in dental implants, bone replacement joints, and components for the hip, elbow, finger, knee, spine, and other body products. And so all these type of actions continue in the plastic industry worldwide. 

The first two selective COX-2 inhibitors to be marketed and subjected to in depth clinical trials were celecoxib and rofecoxib. Both compounds are as effective as standard NSAIDs in rheumatoid arthritis, osteoarthritis and for pain following orthopaedic or dental surgery. Gastrointestinal side effects were far fewer than with comparator diugs and in fact were no... 

Association of Dental Surgeons (1879), where Peirce describes a cement similar to that of Rollins. Many brands were on the market by 1881 (Miller, 1881). 

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. 

Voelker (1916a) reported three early dental silicate cements which appeared in 1895, 1897 and 1902 all proved inadequate. The first successful material was developed by Steenbock (1903,1904) who explicitly sought and formulated a translucent cement (Voelker, 1916a,b). It was marketed by Ascher in 1904 as New Enamel Richters Harvadid cement followed in the same year. Thereafter development was rapid and eight varieties were reported by Morgenstem in 1905. However, from their chemical composition we doubt whether they were sufficiently translucent. 

Many articles have been written on the demand for implants. It is difficult to estimate the market. The most popular implants are likely to be hip, knee, finger, dental root, heart valve, pacemakers and jaw reinforcement. Worldwide the demand is 100,000 heart valves, 220,000 pacemakers, 400,000 hip prostheses and 1,500,000 blood vessel prostheses. 

The divalent mineral-binding effect of CPPs can be put in use in applications where one wants to increase the availability for absorption of these minerals in the gut. Drinks with calcium and iron are examples for commercial uses of CPPs examples can be found especially in the Japanese market. Products for children that incorporate calcium or milk minerals and CPPs in sweets or cookies are found in the South Asian market. As mineral accretion is high during early childhood, incorporation of CPPs provides good solubility and availability for absorption of calcium or zinc and thus is worth considering for infant nutrition. Other possible uses are in calcium-enriched dairy products and natural calcium supplements. In addition, dental applications are obvious, since complexes of calcium, CPPs and phosphate may reduce caries in a dose-dependent fashion. 

This section focuses on adhesives that are used for the assembly of medical devices. In medical device assembly, the primary substrates are plastics, elastomers, and metals. The total medical adhesive market is much larger since it encompasses a broader definition of products. For example, medical adhesives can be used for bonding human tissue, transdermal drug delivery systems, dental restoration, and wound care in addition to medical device assembly. 

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