Tooth Preparation

Tooth Preparation Procedures carried out with regard to the teeth or tooth structures preparatory to specified dental therapeutic and surgical measures, [nih]... 

The pulp of the tooth is a delicate specific tissue and there are severe consequences for its health if it becomes exposed [ 1 ]. Several things can lead to its exposure, specifically trauma of the tooth, dental caries and accidents in tooth preparation. Exposure can be followed by infection and inflammation, resulting in considerable pain to the patient and potential morbidity of the pulp itself. When exposure occurs, therefore, the tooth requires treatment. One approach involves complete removal (extirpation) of the pulp and root canal therapy. 

Alternatively the pulp may be saved by the process of pulp capping. This involves placing some sort of material over the pulp to protect it and maintain its viability so that more extreme treatment (extraction or endodontic therapy) can be avoided [1]. Two possible approaches are available, namely direct pulp capping, in which a bioactive material is placed directly over the exposed pulp, and indirect pulp capping, in which a cavity liner or sealant material is placed over a residual thin layer of dentine, which may be sound or carious. In the latter approach, the pulp has not been exposed, but it is at risk of becoming so either by the progress of the residual caries or by the process of tooth preparation. 

There is evidence that the pulp is more likely to survive if exposure occurs by accident during tooth preparation rather than due to the progression of caries [11,12], This is because caries penetration is inevitably associated with bacterial invasion, and therefore results in infection and inflammation of the pulp [10], By contrast, exposure due to a mechanical misadventure during tooth preparation does not necessarily result in bacterial invasion. Consequently, the exposed pulp does not become infected or inflamed. As a result, teeth repaired by direct pulp capping following this type of exposure are generally better able to survive with their pulp intact than those whose pulps become exposed due to advancing caries [11]. 

A number of salts of the monofluoro- and hexafluorophosphoric acids are known and some are commercially important. The salts of difluorophosphoric acid are typically less stable toward hydrolysis and are less well characterized. Sodium monofluorophosphate [7631-97-2] the most widely used dentifrice additive for the reduction of tooth decay, is best known (see Dentifrices). Several hexafluorophosphates can be prepared by neutralization of the appropriate base using hexafluorophosphoric acid. The monofluorophosphates are usually prepared by other methods (57) because neutralization of the acid usually results in extensive hydrolysis. 

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). 

The phases and their proportions present ia hardened amalgam are controlled by many factors. The composition of the alloy the size, shape, and size distribution of the particles the thermal history of the cast ingot and the comminuted alloy and the surface treatment of the particles are some of the factors for which the manufacturer is responsible. The tooth cavity preparation and the mixing, compacting, and finishing techniques of the dentist can make the difference between satisfactory and unsatisfactory restorations, even with the best of alloys. A minimal amount of residual mercury and porosity are needed to obtain the most serviceable restorations (138). 

Amalgam restorations are prepared by mixing a powdered alloy with mercury to form a plastic moldable mass that is packed or condensed iato the prepared cavity. The cavity is designed to provide mechanical retention, maximum marginal mass, support to absorb the functional stresses transmitted through the restoration, and maximum protection to the remaining tooth stmcture. The restoration reestabUshes the normal tooth anatomical form and function. 

Next, the amalgam must be condensed properly ia the prepared, clean, and dry cavity. In general, the maximum effective load tolerated by the patient should be used on a condenser of optimum size, to remove as much mercury from the mass as possible. The amalgam must be carved to the contour of the lost tooth tissue it is replaciag. 

By far the greatest consumption of pure aqueous phosphoric acid is in the preparation of various salts for use in the food, detergent and tooth-paste industries (p. 524). When highly diluted the free acid is non-toxic and devoid of odour, and is extensively used to impart the sour or tart taste to many soft drinks ( carbonated beverages ) such as the various colas ( 0,05% H3PO4, pH 2,3), root beers ( 0.01% H3PO4, pH 5,0), and sarsaparilla ( 0.01% H3PO4, pH 4.5). 

Ambrose, S.H. 1990 Preparation and characterization of bone and tooth collagen for isotopic analysis. Journal of Archaeological Science 17 431 51. 

This equation predicts a value of 26.8%ofor the zebra at Turkana assuming an average value of 6%o for Lake Turkana water. This predicted value is l%o less than the actual value of 27.8%o. Given the variation in methods of sample preparation and analysis, variation between bone and tooth enamel (Stuart-Williams and Schwarcz 1997), and uncertainty in surface water oxygen isotopic composition, these values are extraordinarily close. Alternatively, if the equation is solved for using the actual value of the Turkana zebra. 

The glass-ionomer cement is the most versatile of all the dental cements and has been developed for a variety of applications (McLean Wilson, 1974, 1977a,b,c Swift, 1988b van de Voorde, 1988 Wilson McLean, 1988 Mount, 1990). Many of its applications depend on its adhesive quality which means that, unlike the non-adhesive traditional filling materials, it does not require the preparation of mechanical undercuts for retention and the consequent loss of sound tooth material. 

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... 

Ambrose, S.H. (1990). Preparation and characterization of bone and tooth collagen for isotopic analysis. Journal of Archaeological Science 17 431 451. Ambrose, S.H. (1993). Isotopic analysis of paleodiets methodological and interpretative considerations. In Investigations of Ancient Human Tissue Chemical Analysis in Anthropology, ed. Sandford, M.K., Gordon and Breach, Langhorne, pp. 59-130. 

Sugar is a common ingredient in prepared foods. When sugar remains on your teeth, bacteria in your mouth convert it into an acid. The principal constituent of tooth enamel is a mineral called hydroxyapatite, Caio(P04)6(OH)2. Hydroxyapatite reacts with acids to form solvated ions and water. (Solvated ions are ions surrounded by solvent particles.) Eventually, a cavity forms in the enamel. 

This application was made between 0700 and 0830 a.m. in cool (air temp., 10 0 clear and windless weather. Both granular and emulsion formulations were incorporated to the 7.5cm depth with a disc cultivator within 15 minutes of application. A second cultivation to the same depth, but at right angles to the first, was completed within 2-3 hours. On May 20th both plots were spring-tooth harrowed for seed-bed preparation for soybean planting on the same day. The only subsequent soil disturbance was a row cultivation in late June to control a severe infestation of quack-grass control of broadleaf weeds was essentially complete with the trifluralin. 

Chlorhexidtne is a symmetrical cationic molecule that is most stable as a salt the highly water-soluble digluconate is the most commonly used preparation. Because of its cationic properties, it binds strongly to hydroxyapatite (the mineral component of tooth enamel), the organic pellicle on the tooth surface, salivary proteins, and bacteria. Much of the chlorhexidine binding in the mouth occurs on the mucous membranes, such as the alveolar and gingival mucosa, from which sites it is slowly released in active form. 

Mouthrinses containing fluoride consist of a concentrated solution that is prepared for use at daily or weekly intervals. As is the case for toothpastes, fluoride from mouthrinses is retained by the dental plaque and increases the concentration in saliva [172]. Mouthrinses have the advantage that their viscosity is low [173], which is aided by the use of ethanol as at least part of the carrier liquid. This enables mouthrinses to penetrate into interproximal regions, and hence carry the fluoride to parts of the tooth that are difficult to access by other means, for example, with toothpastes. 

More recently, it has been shown that topical fluoride preparations do not lead to fluoridation of the hydroxyapatite crystal [181]. Rather they form a calcium fluoride-like substance that is deposited onto the tooth surface and dissolves when the local pH is lowered [182]. The resulting dissolution adjacent to the tooth surface provides a source of soluble fluoride that can be incorporated into the mineral structure, and thus augment remineralisation. 

Decoction. A preparation made by boiling a plant part in water a boiled extract. Dental enamel. A hard, thin, transcluent layer of calcified substance that envelops and protects the dentin of the crown of the tooth. It is the hardest substance in the body and is almost entirely composed of calcium salts. 

Drink liquid iron preparations in water or juice and through a straw to prevent tooth stains... 

The considerable list in Table 6.3 illustrates some of the companies that are currently preparing plant-based biopharmaceutical technologies for commercialization. Steps have been taken toward the development and subsequent commercialization of one of these products, currently in Phase 2 clinical trials and known as CaroRx (licensed to Planet Biotechnology Inc., Hayward, CA) a monoclonal antibody designed for treatment of tooth decay by S. mutans is described in the following text. 

These are the preparations used for temporary relief of toothache by application of a small pledget of cotton soaked with the product into the tooth cavity. Certain local anaesthetic compounds, e.g. benzocaine. 

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