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The best seal - the seal of gold
16-09-2009
Seals of malleable gold - is a seal of gold, sealed directly to the tooth. At the same time apply the golden pins of high-grade gold (24 carats). Seal of malleable gold - a high quality seal, characterized by durability, optimum strength of the walls, marginal adaptation and poliruemostyo surface. In the mouth it is chemically neutral, biocompatible with the gum tissue, do not rust, be re-polishing and contouring through a large period of time.
Seals of malleable gold shows to fill the small carious defects in the pits and fissures (I class at Blake) and cervical tooth defects (V class Blake). Prerequisites to the application of this costly sealing techniques are appropriate oral hygiene, little activity of caries.
The use of seals of malleable gold is contraindicated for large carious defects, close proximity to the bottom of the pulp cavity, in occlusive bearing area at fracture surfaces, unfinished root growth, there parodontitnyh teeth (at the corner of mobility for more than 2 °) and the removal of large trepanatsionnyh defects on the crown.
There are gold leaf (gold foil) and spongy gold (matt gold). Gold foil consists of a 24-ka-selfless rolled gold, which is in the form of a very thin film (thickness of 1.5 microns), together with a gasket of thin paper sewn into the book.
Of the individual sheets of cut parts and twisted into small rolls. To avoid sticking the foil in the processing surface is covered with protective gas (ammonia). The protective layer is removed by heating on a flame in the combustion process of pure (99.9%) of alcohol. After that, gold can also stick together and cold. Rollers are prepared in advance and stored in a special wooden box. Use the golden ridges of prefabrication, which cost above and, due to surface contamination, is not always guaranteed slipaemost.
Spongy gold - it is electrolytically fallen golden powder which is sintered (agglomerated). If the particles stick together better among themselves and with the condensation less destroyed. Using a sponge gold impossible to get a dense, homogeneous non-porous surface. It can be used only to form a basis. The surface of the seal of malleable form of gold from gold leaf. In order to protect the spongy gold from destruction during processing and achieve better workability use different methods. In particular, electrolytic fallen gold powder is applied between two layers of gold leaf and sintered. This matte gold particles interlock with gold leaf. Thus, strips of gold leaf hold together spongy gold, improving condensation. Such material is used to form the basis and must, as is the case with the usual spongy gold, gold leaf trim.
In 1966, Williams (Williams) to improve handling and increase the hardness of gold added to the sponge calcium (0,1-0,5%). In addition, this material is wrapped in gold leaf, resulting in increased surface hardness compared with other seals seals of malleable gold.
In order to reduce rassypchastosti gold powder processing as a means of adding a binder wax. This product is wrapped in gold leaf added, is called Goldent. Prior to treatment, it is heated and wax melted. Furthermore, when heated gold sinters, which prevents its destruction during condensation.
Goldeni-roll contains approximately ten times more gold than the same size roll of sheet gold. Seals of Goldent not be evaded in gold leaf. However, it is expensive, time-consuming processing, during which larger pores are formed, albeit in smaller quantities.
Since the retention of the seal is achieved by sticking with gold, there is no need to create scores.
Initial dissection made cylindrical diamond bur and diamond finirami. All internal angles and then treated with hand tools to the formation of sharp edges. If the cervical edge of the cavity is located in the enamel, it eliminates the hand tool (enamel chisel). Otherwise, the enamel prisms in the cervical area of the tooth is easily dissolved, and formed boundary crack. After dissection impose a cofferdam, and the need to follow the proper retraction of marginal gingiva.
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