When is a crown, inlay, onlay or laminate veneer indicated? (ref. 6)
Preparation Types
Full coverage crown (see Figure 1)

Figure 1. Full coverage crowns.
Indications
Extensive loss of coronal structure is evident
Maximum retention and strength are required of the restoration
Used to support a removable partial denture
For endodontically treated teeth
Partial coverage crown, inlay or onlay (see Figure 2)

Figure 2. Gold onlays.
Indications
Moderate loss of tooth structure is evident
The buccal wall of the tooth must be intact and supported by healthy tooth structure.
Commonly used when occlusion needs to be restored or modified.
Commonly used as a retainer for fixed partial dentures
Porcelain Laminate Veneer (see Figure 3a and 3b)

Figure 3a. Laminate veneers. (labial view)

Figure 3b. Laminate veneers. (lingual view)
Indications
Conservative esthetic alternative to anterior full-coverage crowns
Early considerations for multiple-unit/complex treatments:
1.
Make alginate impressions and diagnostic casts.
2.
Consider the need for a diagnostic wax-up.
3.
Make a bite registration, which is needed by the lab to correctly articulate diagnostic casts.
4.
Take photographs of the patient (especially for maxillary anterior restorations).
5.
Make a facebow record to illustrate how the occlusal and incisal plane of the teeth relates to the face (see Figure 5).

Figure 5. Patient with facebow.
6. Consider the use of an intraoral camera.
Record pre-operative condition.
May provide a computer generated "preview" of the final restoration.




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