The Importance of the Emergence Profile and Tissue Cast
Peter Pizzi, MDT, CDT
Everything laboratory technicians do in the dental process is geared toward creating a lifelike restoration. Whether we use a CAD process or a manual impression and poured cast, our goal is the same. In order to guide ourselves through the restorative sequence, we focus on photographic details and the diagnostics of case planning. However, we sometimes complicate our analysis, overlooking the simplicity of the most important information.
The emergence profile—defined as “the contour of a tooth, restoration, or implant where it emerges from the gingiva”—and its support of the gingival esthetics are key elements in order to create a lifelike restoration. The creation of natural esthetic contours signifies that both the tooth and supporting tissue live in harmony. To achieve this, the preparation design as well as the margin and finish lines are usually placed sub-gingivally with the restorative contour and tissue support created from our restorative materials.
The use of a gingival cast, sometimes known as an alveolar cast, is one of the most critical components. Unfortunately, most laboratories today use a die cast or a removable die cast, generating several challenges. First, there is a major inaccuracy in the die cast. Even more importantly, the die requires a trimming process, which involves the removal of critical tissue information that is needed to correctly develop the emergence profile.
Therefore, while there are several ways to create a tissue cast, there are two preferred methods. The first involves the use of a solid untouched pour of the master impression or scan, followed by the pouring of a virgin die for waxing or scanning. The second method requires the creation of a removable die alveolar cast, which is much more complex but retains the most gingival information. Either of these casts gives the technician control over the emergence profile, thus allowing the development of the proper cervical enamel junction in support of the gingival tissue.
Bench Essentials is a quarterly series in which IDT Editor-in-Chief, Peter Pizzi, MDT, CDT, presents educational lessons about the fundamentals of dental laboratory technology based on his decades of working at the bench and lecturing around the world.