Abstract
Temporary crowns for gum displacement were tested how they work in order to obtain subgingival tooth preparation and impression of abutment tooth accurately and without difficulty. The observation of the displaced gum revealed the following conclusions.
1. They displaced the gum so sufficiently that subgingival tooth preparation was possible without injuring or bleeding of the gum.
2. It is possible to get the impression after the preparation of the abutment tooth without any additional gum displacement due to their long effectiveness.
3. Inflammation of the sulcular epithelium which temporary crowns for gum displacement bring were proportional to the length of the set period ; only slight inflammation was recognized within less than 4 weeks and the sulcular epithelium shows clinically normal appearance especially within one or two day after the setting.
