Crown Preparation Exact positioning and finishing of the prosthetic margin after supragingival preparation with rotary instruments of identical shape. Advantages: Tips are gentle on the soft tissue, thus avoiding haemorrhages that might hamper impression taking Tips create very fine crown margins, which is an essential condition for well-fitting, durable restorations Improved adhesion of the fixing cement thanks to the irregular structure of the crown core Sonic tips: Apart from the Komet sonic handpiece SF1LM, Komet sonic tips can also be used In the Scalers made by the co. W&H (Series Proxeo ZA-55/L/LM/M/LS and Proxeo ST ZE-55RM/BC, series Synea ZA-55/L/LM/M or series Alegra ST ZE-55RM/BC), as well as In the SONICflex&trade handpiece provided by the company KaVo (Series 2000N/L/X/LX or series 2003N/L/X/LX) or In the SIROAIR L of the co. Sirona