Now we say "restoration of a tooth", instead of "sealing of a tooth", and amalgam fillings and composite resin fillings are more often considered to have a deeper medical meaning. Because the sealing of teeth is made with materials which allow simulating a natural tooth either its color or its form and structure. Therapeutic treatment at the stomatologist means treatment of caries of teeth and its complications. Nowadays treatment of caries is carried out at any stage using the advanced stomatologic materials for sealing teeth and root channels.
These days at the disposal of modern stomatology, there are a lot of dental fillings (materials), distinguished by high durability, safety and aesthetic properties. It can be dental fillings (cements), composites or polymers. Features of these materials are presented by the glutinous system which allows a seal reliably to remain in a tooth due to active sticking to a surface. Hardening polymers are formed only under the action of a special lamp's light of the certain spectrum. Polymers enable the stomatologist to generate such a seal that is necessary. Therefore, using materials of polymers allows putting seals on the most various surfaces of a tooth, on forward and back teeth, to restore broken fragments of a tooth, to form a seal level with a surface of a tooth, precisely to select necessary color. These are the cements of new generation possessing a lot of positive properties - high durability, durability, stability to various influences and high cosmetic effect.
The oldest kinds of seals are amalgam fillings, composite resin fillings and seals of stomatologic silicate cements (cements of the first generation). In order to make such a seal stable in the tooth for as long time as possible, it is necessary to keep the highest accuracy with its preparation. Because untreated cement can decompose even under the action of saliva. The seal should be put anew. And the term of durability of a "correct" cement seal is considered two to three years, sometimes it is even more. It is impossible to make any conclusions about its cosmetic effect, because silicate cement absorbs food dyes and is perfectly painted over. And being careless while making up the preparation of the cement can also make the color of it a little yellow. Therefore, it is necessary to consider cement seals as the ancestor of all dental seals, but in a different way.
Dental fillings made of stomatologic plastic were the next step in a filling's evolution. But those seals did not become popular because of their bad reputation. Their use frequently resulted in plural complications such as pulpitises and periodontitis. Difficulties in processing did not allow achieving satisfactory cosmetic effect - soft plastic, and it was very difficult to achieve a balanced surface.
Amalgam seals had rather good reputation when they appeared. They had a "life-span" for 10-15 years or more. One of negative aspects of this kind of seal was the presence of mercury. As a result, Amalgam seals are illegal in many countries around the world.
The following step in the development of dental fillings became the occurrence of new materials. New technology began appearing in the 1960's and is still being used today. Composite materials are strong enough to remain solid for a long time. Unsuccessful coloring and, consequently, low aesthetic properties are considered to be their only drawback. Though quite worthy, representatives of this group of materials with improved properties (Surefil) have appeared recently to great success.
Finally a word or two about cement seals. With the development of dental technology, a new line of cement has appeared on the market that benefit from high durability and stability to various influences.