Abstract
The purpose of this study was to clarify the current working condition of casting ring liners. The questionnaire was completed by 56 dentists and 252 dental technicians. The 50 different liners were used and the number of gold alloy and silver-paradium-gold alloy cast liners used was almost equal. We devided the liners into A-group (Rockwool type) 36.8%, B-group (Ceramic fiber low temperature type) 39.0%, C-group (Ceramic fiber standard type) 4.3%, D-group (Ceramic fiber low-standard type) 11.8% and E-group (Kaolin type) 1.9% for the gold alloy cast. The wet-liner method was used by 44.1% of all respondents, the dry-liner method by 33.1% and petrolatum-painted liner method by 21.8%. The use of the liner differed between dentists (mainly petrolatum-painted liner method) and dental technicians (mainly wet-liner method). Only a small number of respondents reported using a cobalt-chromium alloy cast (58) or a titanium and titanium alloy cast (31). In addition of the cobalt-chromium alloy, titanium and titanium alloy casts used, the reported use of the ring-less cast method was 50% and 55%, respectively.
