If you have ever had serious dental work done, it is likely that you had had a dental impression taken dental impressions are very common and are used for a variety of purposes in the dental field. Impressions can be used to create mouth guards, for aligner therapy inorthodontics, and to make whitening trays, crowns, bridges,veneers, dentures, and more.A dental impression is an imprint of the teeth and mouth from which shaped items can be formed. Dental impressions produce a close replica of your teeth and oral tissue. A metal or plastic “horseshoe” shaped tray is chosen to fit the teeth and gums comfortably. A tray can be molded for either the top teeth, the bottom teeth, or both.zoranm / Getty ImagesHow Dental Impressions Are MadeIn order to make a dental impression, a thick liquid material, such as alginate or polyvinylsiloxane, is dispensed into an impression tray that is shaped like a U in order to properly fit into a mouth.Alginate is found within the cell walls of brown seaweeds. The seaweed is part of the phylum Phaeophyceae family and is harvested internationally to be converted into the raw material sodium alginate. This substance is what’s used to create theAlginateproduct.Depending on the species of seaweed, various chemical structures can be found within each plant.There are certain species of plant which will yield a product of higher gelling capacity; perfect for molding hands or feet. Some plants will offer a weaker gel that it’s used within the medical genre of application. The color of the gel is also dependent on the type of plant used as well.As a naturally occurring product found withinbrown seaweed, Alginate is considered both food and dermatologically safe. Alginate is known for its ability to absorb water, making it a useful product in the medicinal field. It is currently found in some slimming aids (weight loss assistance), thickening agents for soups, jellies, ice cream, cosmetics, drinks, and pharmaceutical preparations.There are two main types of impression trays: stock trays and special trays. Stock trays are manufactured in bulk in a variety of shapes and sizes. A dentist will then select the closest-matching stock tray in size and shape for each individual patient. Special trays, which are also known as custom trays, are produced to the exact specifications of a particular individual.The particular type of liquid that is utilized for impression taking varies based on what the impression is needed for. Some impressions call for a rigid mold, while other impressions require more elastic, or pliable material.After the liquid material is poured into the tray, it is then placed onto either the upper or lower set of teeth so that it covers the entire dental arch. Like the material that is used, the area that the impression covers varies depending on what kind of work the patient needs to have done. The roof of the mouth is included for an upper impression, and the floor of the mouth and under the tongue is included in lower impressions.After a preset amount of time, the liquid material sets and hardens, and become a solid rubber mass. The tray is then removed from the mouth and is sent to the clinical laboratory or dental laboratory for further processing.Stone is poured into the hardened impression and when set a dental cast is produced. This forms an almost exact replica of the mouth from which it has been molded.Uses of Dental ImpressionsDental impressions have many uses in the dental field and are commonly used in dentistry for making:Custommouth guardsCustom take-home whitening traysCustom dental trays used for precise impression takingCrowns, bridges, and veneersDenturesCustom abutments fordental implantsModels for diagnostic studyModel for apermanent dental recordbefore and after dental treatmentOrthodontics
If you have ever had serious dental work done, it is likely that you had had a dental impression taken dental impressions are very common and are used for a variety of purposes in the dental field. Impressions can be used to create mouth guards, for aligner therapy inorthodontics, and to make whitening trays, crowns, bridges,veneers, dentures, and more.
A dental impression is an imprint of the teeth and mouth from which shaped items can be formed. Dental impressions produce a close replica of your teeth and oral tissue. A metal or plastic “horseshoe” shaped tray is chosen to fit the teeth and gums comfortably. A tray can be molded for either the top teeth, the bottom teeth, or both.
zoranm / Getty Images
How Dental Impressions Are Made
In order to make a dental impression, a thick liquid material, such as alginate or polyvinylsiloxane, is dispensed into an impression tray that is shaped like a U in order to properly fit into a mouth.
Alginate is found within the cell walls of brown seaweeds. The seaweed is part of the phylum Phaeophyceae family and is harvested internationally to be converted into the raw material sodium alginate. This substance is what’s used to create theAlginateproduct.Depending on the species of seaweed, various chemical structures can be found within each plant.
There are certain species of plant which will yield a product of higher gelling capacity; perfect for molding hands or feet. Some plants will offer a weaker gel that it’s used within the medical genre of application. The color of the gel is also dependent on the type of plant used as well.
As a naturally occurring product found withinbrown seaweed, Alginate is considered both food and dermatologically safe. Alginate is known for its ability to absorb water, making it a useful product in the medicinal field. It is currently found in some slimming aids (weight loss assistance), thickening agents for soups, jellies, ice cream, cosmetics, drinks, and pharmaceutical preparations.
There are two main types of impression trays: stock trays and special trays. Stock trays are manufactured in bulk in a variety of shapes and sizes. A dentist will then select the closest-matching stock tray in size and shape for each individual patient. Special trays, which are also known as custom trays, are produced to the exact specifications of a particular individual.
The particular type of liquid that is utilized for impression taking varies based on what the impression is needed for. Some impressions call for a rigid mold, while other impressions require more elastic, or pliable material.
After the liquid material is poured into the tray, it is then placed onto either the upper or lower set of teeth so that it covers the entire dental arch. Like the material that is used, the area that the impression covers varies depending on what kind of work the patient needs to have done. The roof of the mouth is included for an upper impression, and the floor of the mouth and under the tongue is included in lower impressions.
After a preset amount of time, the liquid material sets and hardens, and become a solid rubber mass. The tray is then removed from the mouth and is sent to the clinical laboratory or dental laboratory for further processing.
Stone is poured into the hardened impression and when set a dental cast is produced. This forms an almost exact replica of the mouth from which it has been molded.
Uses of Dental Impressions
Dental impressions have many uses in the dental field and are commonly used in dentistry for making:
4 Sources
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Scheller-Sheridan C.Basic Guide to Dental Materials. Hoboken, NJ: Wiley.
Cervino G, Fiorillo L, Herford AS, et al.Alginate materials and dental impression technique: a current state of the art and application to dental practice.Mar Drugs. 2018;17(1). doi:10.3390/md17010018
Kimica.Applications with alginates.
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