Comparison of quality of impression and clinical performance after gingival displacement with magic foam cord and gingival retraction cord - An in vivo study

Purpose: The purpose of this in vivo study was to investigate the effectiveness of two different gingival displacement techniques. Method: Thirty nine prepared abutment teeth (n=39) of 19 patients were evaluated in this prospective clinical study. The ability to displace gingiva was measured both clinically and microscopically, by the accurate reproduction of the preparation finish line in the final impression made in a special tray using a double mix single step technique after using two displacement methods at an interval of 1 week for the same tooth under similar clinical conditions. For microscopic evaluation, the impressions were sectioned bucco-lingually and mesio-distally along the prepared tooth and examined under a light microscope (Olympus CH 20i) under 4x magnification. The impressions were evaluated using McNemar test (α =.05). The mean horizontal and vertical displacement between the groups was evaluated using student ‘t’ test. (α =.05). Results: The Magic foam cord (MFC) group showed significant results for time spent (P<0.00005), ease of application (P<0.02), comfort (P<.022) and injury as compared to the impregnated cord (IC) group (P<0.003). Dilation observed in IC group was significantly greater than the MFC group (P<.016). However, the microscopic evaluation revealed no statistically significant difference between the two materials tested (P>.402) Conclusion: Both groups were equally effective in achieving horizontal and vertical gingival displacement. However from a clinical point of view MFC was superior in comparison to IC.