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Dentine exposure & opening of dentine tubules

Due to:

• Caries.
• fractured tooth.
• marginally defective restoration.
• cement failure.
• gingival recession, attrition, abrasion, erosion.

Previously

http://www.becomedentist.com/2008/12/diagnosis-for-pulp-disease/

Do you know about memory

I have this link

7. Which of the following sentences describes the construction of the removable partial dentures?

b they are removable and attached to teeth with clasps - c d

8. Full denture bases are usually made from which of the following materials?

c. Acrylic resin - correct

9. Which of the following metals currently are used in dental alloys?

a. Gold b. Mercury c. cobalt cromium d. nickel - correct

10. Acrylic resins are used in which of the following?

b Denture bases c. artificial teeth - correct

11. Which of the following materials are used for dental implants?

c. Titanium - d

Denture bearing structures divide into 2 types:

1 anatomy of supporting structures

2 anatomy of peripheral / limiting structures

Limiting structures

1. Labial vestibule

2. Buccal vestibule

3. Distal extension

4. Lingual border

5. Retromolar fossa

6. Sublingual gland region

7. Alveololingual sulcus

Link here

http://www.lessons4living.com/depression_test2.htm

1. Small portion of anterior tooth would most likely be restored with which of the following?

b. composite resin - correct

2. The restorative material used to restore a small portion of an anterior tooth should have which of the following properties?

a. Esthetics + c - correct

3. A portion of a posterior tooth that is subject to high biting forces would likely be restored with which of the following?

a. Amalgam + c - correct

4. A direct restorative material used frequently to restore a portion of a posterior tooth that is subject to large biting forces would possess which of the following properties?

b. High strength  - correct

5. A full crown on a maxillary anterior tooth may be restored with which of the following restorative materials?

a. ceramic d. - correct

6. An anterior fixed partial denture could have facings constructed of which of the following materials?

abc - correct

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• Substance abuse. Nearly 30% of people with substance abuse problems also have major or clinical depression.

Discuss diet causes in early childhood caries

The American Academy of Pediatric Dentistry says that frequent consumption of liquids containing fermentable carbohydrates (e.g., juice, milk, formula, soda) increases the risk of dental caries due to prolonged contact between sugars in the liquid and cariogenic bacteria on the teeth. Poor feeding practices without appropriate preventive measures can lead to a distinctive pattern of caries in susceptible infants and toddlers commonly known as baby bottle tooth decay (BBTD), a form of severe early childhood caries (ECC). Frequent bottle feeding at night, and extended and repetitive use of a no-spill training cup are associated with ECC. Children experiencing caries as infants or toddlers have a much greater probability of subsequent caries in primary and permanent teeth

Crown is restorations of teeth using materials that fabricated indirect in the lab  which cemented into place.

Traditionally, the teeth to be crowned are prepared by a dentist and records are given to a dental technician to fabricate the crown or bridge, which can then be inserted at another dental appointment. The main advantages of the indirect method of tooth restoration include:

* fabrication of the restoration without the need for having the patient in the chair
* the utilization of materials that require special fabrication methods, such as casting
* the use of materials that require intense heat to be processed into a restoration, such as gold and porcelain.

The restorative materials used in indirect restorations possess superior mechanical properties than do the materials used for direct methods of tooth restoration, and thus produce a restoration of much higher quality.

As new technology and material chemistry has evolved, computers are increasingly becoming a part of crown and bridge fabrication, such as in CAD/CAM technology.

Details is here:

http://en.wikipedia.org/wiki/Crown_(dentistry)

Teeth must be cut until its have retention from tooth surface and cement.

They are shoulder and syamfer margin.

For anterior teeth incisor shoulder 1-1.5 mm is trim

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Margin
A palatal view of a maxillary premolar during a crown lengthening procedure. This procedure is being performed because the height of the crown preparation is too short to obtain adequate retention but the minimum of 3 mm to allow for biologic width have already been realized.

The most coronal position of untouched tooth structure (that is, the continual line of original, undrilled tooth structure at or near the gum line) is referred to as the margin. This margin will be the future continual line of tooth-to-restoration contact, and should be a smooth, well-defined delineation so that the restoration, no matter how it is fabricated, can be properly adapted and not allow for any openings visible to the naked eye, however slight. An acceptable distance from tooth margin to restoration margin is anywhere from 40-100 ?m. However, the R.V. Tucker method of gold inlay and onlay restoration produces tooth-to-restoration adaptation of potentially only 2 ?m, confirmed by scanning electron microscopy; this is less than the diameter of a single bacterium.

Naturally, the tooth-to-restoration margin is an unsightly thing to have exposed on the visible surface of a tooth when the tooth exists in the aesthetic zone of the smile. In these areas, the dentist would like to place the margin as far apical (towards the root tip of the tooth) as possible, even below the gum line. While there is no issue, per se, with placing the margin at the gumline, problems may arise when placing the margin too subgingivally (below the gumline). First, there might be issues in terms of capturing the margin in an impression to make the stone model of the prepared tooth (see stone model replication of tooth in photographs, above). Secondly, there is the seriously important issue of biologic width. Biologic width is the mandatory distance to be left between the height of the alveolar bone and the margin of the restoration, and if this distance is violated because the margin is placed too subgingivally, serious repercussions may follow. In situations where the margin cannot be placed apically enough to provide for proper retention of the prosthetic crown on the prepared tooth structure, the tooth or teeth involved should undergo a crown lengthening procedure.
The natural tooth’s crown (A) meets the root (B) at the cementoenamel junction, and it is roughly at this point that the gingival attachment begins at the base of the gingival sulcus (G). The margin of the prosthetic crown may not violate the 2 mm of biologic width from the base of this sulcus to the height of the alveolar bone (C) if complications are to be avoided.

There are a number of different types of margins that can be placed for restoration with a crown. There is the chamfer, which is popular with full gold restorations, which effectively removed the smallest amount of tooth structure. There is also a shoulder, which, while removing slightly more tooth structure, serves to allow for a thickness of the restoration material, necessary when applying porcelain to a PFM coping or when restoring with an all-ceramic crown (see below for elaboration on various types of crowns and their materials). When using a shoulder preparation, the dentist is urged to add a bevel; the shoulder-bevel margin serves to effectively decrease the tooth-to-restoration distance upon final cementation of the restoration.

Why Is a Dental Crown Needed?

A dental crown may be needed in the following situations:

1. To protect a weak tooth (for instance, from decay) from breaking or to hold together parts of a cracked tooth
2. To restore an already broken tooth or a tooth that has been severely worn down
3. To cover and support a tooth with a large filling when there isn’t a lot of tooth left
4. To hold a dental bridge in place
5. To cover misshaped or severely discolored teeth
6. To cover a dental implant

What Types of Crown Materials Are Available?

Permanent crowns can be made from all metal, porcelain-fused-to-metal, all resin, or all ceramic.

*   Metals used in crowns include gold alloy, other alloys (for example, palladium) or a base-metal alloy (for example, nickel or chromium).

* Porcelain-fused-to-metal dental crowns can be color matched to your adjacent teeth (unlike the metallic crowns).

* All-resin dental crowns are less expensive than other crown types. However, they wear down over time and are more prone to fractures than porcelain-fused-to-metal crowns.

* All-ceramic or all-porcelain dental crowns provide the best natural color match than any other crown type and may be more suitable for people with metal allergies.

* Temporary versus permanent. Temporary crowns can be made in your dentist’s office whereas permanent crowns are made in a dental laboratory. Temporary crowns are made of acrylic or stainless steel and can be used as a temporary restoration until a permanent crown is constructed by the dental laboratory.

http://www.webmd.com/oral-health/dental-crowns

ADVANTAGES:
Perhaps the most important advantage of immediate dentures is that you never need to appear in public without any teeth.
1. The form, size and arrangement of your natural teeth can more closely be duplicated when some teeth remain in your mouth.
2. When immediate dentures are inserted, they act as a bandage and help to reduce bleeding.
3. Immediate dentures protect the tissues at the sensitive extraction sites from irritation which might result from the tongue and food. This can mean less discomfort for you than with conventional denture construction.
4. Immediate dentures can enable you to establish your speech patterns more easily. You do not have to learn to speak without teeth and then relearn once dentures are made.
5. With immediate dentures you can chew better than you could without teeth during the normal waiting period for conventional dentures.
6. If dentures do not replace the natural teeth within a short time, the cheeks tend to fall in.
7. If you remain without teeth for some time, you may develop oral habits that will interfere with your ability to learn how to use dentures properly.

http://www.dental-design.com/immediate_dentures.htm