Term
Porcelain Fused to Metal Crown
--PFM-- |
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Definition
| Crown or bridge which is made with a metal substructure. |
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Term
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Definition
| Most natural looking restoration that can be made in the dental lab. There is NO METAL substructure or "coping" under the porcelain. |
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Term
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Definition
When esthetics are not an issue, such as the lower 1st and 2nd molars, the dentist may recommend a gold crown.
One of the oldest materials used in dentistry and is still one of the best in terms of strength and longevity. |
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Term
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Definition
| Restorations also made by an outside commercial lab. When the remaining tooth structure is sufficiently strong, the dentist may opt for a gold inlay or onlay, rather than a full crown. This is a more conservative treatment. |
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Term
| PORCELAIN inlays and onlays |
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Definition
| Usually bonded to the tooth using an all-resin cement together with the usual bonding procedures. |
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Term
| Implant crowns and bridges |
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Definition
| Crowns and bridges made over dental implants are done in areas of the mouth which are missing teeth. The procedure for implant crowns in approximately the same as for natural teeth. |
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Term
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Definition
| This material looks like a green "jelly bean" candy. When placed in a very hot water, the "jelly bean" softens and becomes very sticky. It is then placed on the occlusal of the crown to be removed and the patient is instructed to bite down on it. After cooling with air, the patient opens their jaw w/ a quick motion and the crown usually comes off the tooth. |
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Definition
| This air operated jackhammer-like device is used by the dentist to forcibly remove crowns and bridges. It must be used with care to avoid breaking the tooth. |
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Definition
| These are useful in many procedures including C&B. They can be dipped in blood clotting agents (HEMODENT) using cotton pliers and scrubbed around a prepared tooth to stop the bleeding which sometimes occurs during tooth preparation. |
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Term
| Bite registration material or Bite Wax |
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Definition
| Bite registration material is a type of impression material that sets very fast (about 30 seconds). It is injected on the occlusal surface of the teeth and the patient is instructed to close into their normal bite. This enables the plaster models to be later fitted together by the lab or the dentist in the correct biting position. |
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Term
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Definition
| This material resembling string is packed (Using the cord packing instrument) around the tooth to temporarily push the gums away from the tooth surface. The string is cut in a length so as to go completely around the tooth. The string is then packed into the sulcus between the tooth and gums and left for several minutes. When the cord is removed, a small trench around the tooth is created which allows the impression material to capture the margins of the crown preparation. The cord comes in a variety of thicknesses. |
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Term
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Definition
| This sticky substance is sprayed or painted on the impression tray in the areas where the impression material will be placed. Its purpose is to keep the impression material from being pulled out of the tray when removing the tray from the mouth. |
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Term
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Definition
This liquid is a blood clotting agent which is sometimes used to help stop bleeding around a prepared tooth. Blood will prevent the impression material from accurately flowing around the tooth and must be eliminated.
The RETRACTION CORD is sometimes dipped in this prior to packing, or a cotton pellet can be used to wipe around the gums.
Hemodent has become sort of a generic name for any brand of blood clotting chemical agent. Another popular brand is Astrigident, often loaded into disposable syringes. The needle tips have small brushes which enable the chemical to be scrubbed into the bleeding area to stop it quickly. |
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Definition
| This is a bur coated with diamond particles and is usually used in a crown preparation instead of the carbide burs used in cavity preparations. |
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Definition
| This is a weak cement used to cement ACRYLIC TEMPORARIES onto the tooth until the permanent one returns from the lab. A permanent crown or bridge can also be cemented with this if it is desired to remove them at some future date. It comes in two tubes and must be mixed on a mixing pad like DYCAL. |
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Term
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Definition
| This instrument is useful in removing hardened cement from around a newly cemented crown or bridge. It has sharp, pointed ends. |
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Term
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Definition
| This instrument is used to pack the RETRACTION CORD or string between the tooth and gums prior to the final impression. It looks almost identical to the interproximal carver (IPC) instrument from the amalgam setup except the blade ends are much thicker so as to push the cord into the sulcus. |
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Term
| crown and bridge scissors |
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Definition
| Short, curved bladed scissors used to trim the metal temporary crowns and cut the retraction cord. |
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Term
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Definition
| A thin bladed spatula used to mix various cements used in C&B. |
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Term
| Crown and Bridge impression materials |
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Definition
They differ from alginate impression materials in that they:
Are NOT mixed with water. They are usually mixed from 2 components: A catalyst and a base.
Are MORE ACCURATE than alginate impressions.
Set more slowly than alginate impressions.
Do NOT HAVE TO BE POURED UP right away as they will not dry out and distort like alginate which is mixed w/ water. |
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Term
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Definition
| Used to squirt the impression material into the trench around the tooth made by the RETRACTION CORD. By doing so, it helps to capture the detail of the critical margin area and also helps prevent air bubbles or voids in the impression. While this type of impression syringe is still used by some, it can be messy and difficult to clean up compared to the "gum" systems now in vogue. |
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Term
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Definition
| provide a means to carry the semi liquid impression material to the mouth and press it around the teeth. The most popular trays are disposable and made of plastic. They are used once then disposed of. |
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Term
| Cartridge "gun" type impression system |
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Definition
| Much faster way of mixing and delivering the impression material to the doctor. There are many different brands on the market. |
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Term
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Definition
2 jars, again having the usual CATALYST and BASE materials in them. An equal amount from each jar is removed and kneaded together (mixed) with the fingers until the two colors are blended.
The assistant must remove rubber gloves and rinse hands off before mixing putty as the residue on the gloves will cause the putty not to set! As an alternative, some offices use a HEAVY BODY gun material in place of the PUTTY. The assistant then injects this into the impression tray. |
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Term
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Definition
| Comes in cartridges which must be loaded in a caulking gun-like device. A new mixing tip is attached to the end and the material is either injected directly onto the tooth or the impression tray. The light body wash material is shown loaded in the "gun" and ready to be injected onto the crown or bridge preparation. This system is by far the most popular as it is the fastest to set up and there is virtually no cleanup. |
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Term
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Definition
| An impression (usually with alginate) taken of the arch opposing the tooth (or teeth) being prepared for a crown or bridge. This is poured up in the lab and enables the lab technician to shape the biting surfaces to it the opposing teeth. The counter impression step and bite registration step can be eliminated if a TRIPLE TRAY technique is used. |
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Term
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Definition
Does 3 things w/ one tray.
The impression, the counter impression, and the bite registration.
Its use is somewhat limited however to single crowns or very small bridges. The technique can be summarized as follows. The CORD is packed around the tooth prep. The assistant mixes the putty in the usual manner while the dentist inject the preparation w/ the light body gun material. The asst loads both sides fo the triple tray w/ a "sausage" of putty and hands it to the doctor. The doctor inserts the triple tray in the mouth and has the patient bite closed into their normal bite. The triple tray thus takes the impression, the counter impression, and records the bite. |
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