Partial Dentures
1.Fixed Partial Dentures
- A. CROWN AND BRIDGEBridges and crowns are fixed prosthetic devices that are cemented onto existing teeth or implants by a dentist or prosthodontist.
- Crowns are used most commonly to entirely cover or “cap” a damaged tooth or cover an implant.
- Bridges are commonly used to cover a space if you’re missing one or more teeth.
Why Is a Dental Crown Needed?
A dental crown may be needed in the following situations:
- To protect a weak tooth (for instance, from decay) from breaking or to hold together parts of a cracked tooth
- To restore an already broken tooth or a tooth that has been severely worn down
- To cover and support a tooth with a large filling when there isn’t a lot of tooth left
- To hold a dental bridge in place
- To cover misshapened or severely discolored teeth
- To cover a dental implant
- To make a cosmetic modification
- For children, a crown may be used on primary (baby) teeth in order to:
- Save a tooth that has been so damaged by decay that it can’t support a filling.
- Protect the teeth of a child at high risk for tooth decay.
What Types of Crowns Are Available?
Permanent crowns can be made from stainless steel, all metal (such as gold or another alloy), porcelain-fused-to-metal, all resin, or all ceramic.
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- Metal crowns
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Metals used in crowns include gold alloy, other alloys (for example, palladium), or a base-metal alloy (for example, nickel or chromium). Compared with other crown types, less tooth structure needs to be removed with metal crowns, and tooth wear to opposing teeth is kept to a minimum. Metal crowns withstand biting and chewing forces well and probably last the longest in terms of wear down. Also, metal crowns rarely chip or break. The metallic color is the main drawback. Metal crowns are a good choice for out-of-sight molars.
- Porcelain-fused-to-metal
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These dental crowns can be color matched to your adjacent teeth (unlike the metallic crowns). However, more wearing to the opposing teeth occurs with this crown type compared with metal or resin crowns. The crown’s porcelain portion can also chip or break off. Next to all-ceramic crowns, porcelain-fused-to-metal crowns look most like normal teeth. However, sometimes the metal underlying the crown’s porcelain can show through as a dark line, especially at the gum line and even more so if your gums recede. These crowns can be a good choice for front or back teeth..
- All-ceramic or all-porcelain
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These dental crowns provide better natural color match than any other crown type and may be more suitable for people with metal allergies. However, they are not as strong as porcelain-fused-to-metal crowns and they wear down opposing teeth a little more than metal or resin crowns. All-ceramic crowns are a good choice for front teeth.
- B. IMPLANT
- A dental implant (also known as an endosseous implant or fixture) is a surgical component that interfaces with the bone of the jaw or skull to support a dental prosthesis such as a crown, bridge, denture, facial prosthesis or to act as an orthodontic anchor.
- There are different approaches to placement dental implants after tooth extraction. The approaches are:
- Immediate post-extraction implant placement.
- Delayed immediate post-extraction implant placement (two weeks to three months after extraction).
- Late implantation (three months or more after tooth extraction).
- There are also various options for when to attach teeth to dental implants classified into:
- Immediate loading procedure.
- Early loading (one week to twelve weeks).
- Delayed loading (over three months)
2. Removable Partial Dentures
Partial dentures are used when one or more natural teeth remain in the upper or lower jaw.
- A. CAST PARTIAL DENTURE
COMPONENTS: Cast metal framework for retention, tissue colored acrylic base and replacement teeth
ADVANTAGES:
- Ease of adjustability
- Functional success
- B. FLEXIBLE DENTURE
- The use of aesthetic flexible removable partial dentures (FRPD) gives a Fast service and better aesthetics than conventional metal-based removable partial dentures (RPD).
- From the perspective of my personal clinical experience, the facts are simple: FRPDs (such as Valplast) work extremely well in some situations, and reasonably well in others.
- In the small number of patients I have observed who have worn FRPDs for an extended period of time, I have not seen bone damage or resorption in the traditional pattern of posterior ridge resorption (saddle ridge) that is so common under chrome/acrylic saddles used on metal-based RPDs.
- Present observations reveal that patient satisfaction with FRPDs is high, the equipment costs and technology to make them are low, and the aesthetics can also be outstanding when compared to conventional metal-based RPDs.
- FRPDs have also been used successfully as obturators in conjunction with maxillectomy procedures. The weight of the appliance (Valplast) is usually about one third that of the conventional obturator.
- C. ACRYLIC PARTIAL DENTURE
An acrylic removable partial denture consists of an acrylic resin denture base, artificial teeth, and wrought wire clasps.
Types of acrylic partial dentures
- Temporary removable partial denture: It is a removable prosthesis used temporarily for a period of time until a more definite prosthesis can be provided.
- Interim removable partial denture: A dental prosthesis to be used for a short intend of time as an artificial substitute for missing natural teeth.
- Transitional removable partial denture:A partial denture which is to serve as a temporary prosthesis and to which more artificial teeth will be added as more teeth are lost and which will be replaced after post-extraction and tissue changes have occurred.
- Treatment partial denture: A dental prosthesis used for the purpose of treating or conditioning the tissue.
- Immediate partial denture: It is prosthesis used to replace one or more teeth and is inserted on the day of extraction of teeth. It is a partial denture constructed before the extraction of unwanted teeth and is inserted immediately.
