Utilization of Elastometric Impressions in Fixed Prosthodontics
A Case Presentation
Ernesto A. Lee, DMD
This study illustrates a technique protocol that yields accurate, predictable impressions on a consistent basis. Upon reviewing this study, the reader should have:
- As understanding of the basic principles involved in obtaining impressions for simple and complex restorations.
- An awareness of the advantages and disadvantages of several impression taking protocols
The technical complexity inherent in fixed prosthodontic treatment is compounded by the necessity to utilize an indirect approach, where fabrication occurs extraorally at the dental laboratory and the completed restorations are subsequently retrofitted in the oral cavity. One fundamental aspect in the fabrication of indirect restorations is the procurement of an accurate impression from which a refractory model can be created to precisely replicate the intraoral environment. Although numerous materials and techniques have been advocated, predictable impression taking remains a challenge for a majority of practitioners--particularly in cases that involve multiple abutments.
Whereas the companion presentation to this will discuss the impression procedure and the role of refractory dies and models, the following will address material selection and soft tissue management in elastomeric impressions.
For the clinician involved in complex reconstructions, the ability to consistently attain accurate impressions acquires added significance due to the additional time and effort involved in preparation for the impression procedure, as well as the increased expenses associated with remakes that result from inaccuracies. The technique for the clinical impression procedure and the role of refractory dies and models are also important considerations that should be readily understood by the savvy clinician.
*Director, Postdoctoral Periodontal Prosthesis, University of Pennsylvania, Philadelphia, Pennsylvania; private practice, Bryn Mawr, Pennsylvania
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