Eliminating the challenges of crown removal or endodontic access through restorations
Fig. 1: Great White Z diamond coated burs utilised for zirconia crown removal or endodontic access and metal cutter carbide bur for use on all-metal crowns or the metal base of porcelain-fused-to-metal restorations.
Fig. 2: The diamond-coated bur is held against the buccal surface of the crown with light pressure and moved in a direction that is parallel to the long axis of the diamond-coated bur to create a slot through the ceramic.
Fig. 3: The diamond-coated bur continues to be used in a direction that is parallel to its long axis,
sawing through the ceramic until either dentine (ceramic crown) or metal (porcelain-fused-to-metal crown) is encountered.
Fig. 4: A slot is next cut across the occlusal surface in a similar manner that is continuous with the slot cut on the buccal surface, again moving the diamond-coated bur parallel to its long axis.
Fig. 5: Crown removal of an anterior crown requires the buccal slot to continue over the incisal edge to the lingual surface.
Fig. 6: A flat-bladed instrument tip is inserted in the buccal groove and
rotated left to right to create torque to split the crown at the slots.
Fig. 7: A round diamond-coated bur is used with light pressure to outline the access form desired.
Fig. 8: Once the crown material has been penetrated to the dentine in the outline form, access through the crown is completed.
Fig. 9: After access through the zirconia or ceramic crown with the round diamond-coated bur, a carbide bur is utilised to complete endodontic access to unroof the pulp chamber.
Fig. 10: Unroofing the pulp chamber may be accomplished with the diamond-coated bur or a carbide bur (practitioner preference), and the endodontic access is completed.
Fig. 11: The diamond-coated bur is used to create the slot in the ceramic to the metal substructure with a porcelain-fused-to-metal crown.
Fig. 12: The carbide bur is utilised to continue the slot through the metal to the underlying dentine.
Fig. 13: The slot has been completed through the porcelain-fused-to-metal material and is ready for insertion of the crown remover instrument.
Fig. 14: Following the outline formed with the round diamond-coated bur to the underlying metal substructure of the crown, the carbide bur is utilised to complete endodontic access to unroof the pulp chamber.
Other photo galleries you may be interested in:
February 26, 2013
Chicago Dental Society
Photos by Fred Michmershuizen and Sierra Rendon, Dental Tribune America.