Depth gauge and method of treating a depth gauge

A surgical instrument for use in the surgical procedure for implanting a dental implant system of the type which includes:

• a fixture component part having a leading end and a trailing end and adapted to be anchored in a jaw bone of a patient by insertion of the leading end thereof into a bore which extends into the jaw bone from a surface thereof, the fixture component part being a standard fixture component part of predetermined length and selected from a set of standard fixture component parts of different predetermined lengths so that on anchorage of the fixture component part in the jaw bone the trailing end is essentially flush with the surface of the jaw bone;
• and
• an abutment component part for bridging a layer of soft tissue which covers the surface of the jaw bone to couple a dental prosthesis to the fixture component part, the abutment component part having a leading end which is adapted to be inserted through a surface of the soft tissue layer and to mate with the trailing end of the fixture component part in the jaw bone and a trailing end which when the leading end of the abutment component part mates with the trailing end of the fixture component part projects from the surface of the soft tissue layer and is adapted to support the dental prosthesis, the abutment component part being a standard abutment component part of predetermined length and selected from a set of standard abutment component parts of different predetermined lengths so that when the leading end of the abutment component part mates with the trailing end of the fixture component part essentially only the trailing end of the abutment component part which supports the dental prosthesis projects from the surface of the soft tissue layer;
• wherein the surgical instrument comprises:
• a depth gauge body having a leading end, a trailing end and an outer peripheral surface extending between the leading and trailing ends,
• wherein the leading end of the depth gauge body is a replica of the leading end of the abutment component part and adapted to be inserted through the surface of the soft tissue layer to mate with the trailing end of the fixture component part in the jaw bone,
• wherein the outer peripheral surface of the depth gauge body is provided with a series of alternate dark and light colored bands of predetermined widths, the boundary lines between adjacent dark and light colored bands representing standard abutment component parts of different predetermined length in the set thereof,
• and further wherein when the leading end of the depth gauge body mates with the trailing end of the fixture component part in the jaw bone the depth of the soft tissue layer is able to be determined from the boundary lines which project from the surface of the soft tissue layer whereby a standard abutment component part of correct predetermined length is able to be selected from the set of standard abutment component parts.