Gingival Retraction - Techniques and Materials: a Review

Though the necessity to place the finish line into the gingival sulcus obviously has a negative effect on the quality of the impression,4,8-10 aspects of gingival retraction have only been sparsely investigated.3-5 The aim of gingival retraction is to allow access for the impression material beyond the abutment margins and to create space for the impression material to be sufficiently thick. Tear resistance of the impression material can be affected by the material thickness.6 Gingival retraction should be mandatory prior to impression so as to expose the prepared tooth surfaces.7-8 Impression with less sulcular width have higher incidences of voids, tearing of impression materials, and reduction in marginal accuracy.9-10 Occasionally, gingival retraction is required in order to permit the completion of tooth preparation or to allow cementation of laboratory-manufactured restorations.11 A number of studies have been done on the various materials and methods used for gingival retraction.7