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. Copyright © 1999 3M. All rights reserved.