title: The effect of displacement time on gingival crevice width.
abstract: The authors investigated the length of time medicated displacement cord should remain in the gingival crevice prior to impression making. A silk cord (Deknatel) was placed into the sulcus and was not removed during the study. Medicated cords (Hemodent on Ultrapak #1) were placed into the gingival sulcus for 2, 4, 6, and 8 minutes. Following cord removal, closure of the sulcus was recorded at intervals using a miniature video camera. Crevicular widths were measured at the midbuccal and transitional line angle areas. At both the midbuccal and transitional line angle areas, gingival crevices displaced for 2 minutes were significantly smaller at 20 seconds (P < .05) than crevices following displacement for 4, 6, and 8 minutes. No significant difference in crevicular width was found at any time period after cord removal for crevices displaced for 4, 6, and 8 minutes. At the transitional line angle, crevicular widths were significantly smaller than at the midbuccal at 20 seconds for all times and remained so up to 180 seconds. To achieve a crevicular width of 0.2 mm, cord should remain in the gingival crevice for an optimum time of 4 minutes prior to impression making when using the materials evaluated in this study.
authors.affiliation: Section of Oral Rehabilitation, Maurice and Gabriela Goldschleger School of Dental Medicine, University of Tel Aviv, Israel.
authors.forename: H
authors.initials: H
authors.lastname: Baharav
authors.forename: B Z
authors.initials: BZ
authors.lastname: Laufer
authors.forename: Y
authors.initials: Y
authors.lastname: Langer
authors.forename: H S
authors.initials: HS
authors.lastname: Cardash
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D003761:Dental Impression Technique / Q000295:instrumentation; D005260:Female; D005881:Gingiva; D006801:Humans; D008297:Male; D008875:Middle Aged; D013997:Time Factors