Appliance for dental navigation

A method for mapping a selected position on or within a human jaw to a corresponding position in a volumetric CT (computerized X-ray tomography) image of that jaw, the method comprising:

• providing a moldable retainer appliance;
• molding the retainer appliance to have an appliance geometry that mates with a surface geometry of at least a portion of the human jaw, such that when mated to the human jaw, the retainer appliance resists displacement relative to the human jaw;
• hardening the appliance to retain the appliance geometry and resist deformation;
• providing an arm comprising a moldable link portion and a rigid fixation portion;
• rigidly attaching the link portion to the retainer appliance to maintain a fixed spatial mapping between the fixation portion and the retainer appliance to provide a fabricated appliance;
• detachably and rigidly attaching a CT marker including a fiducial detectable in the volumetric CT image to the fixation portion at a CT marker connection region to provide an imaging appliance including the fabricated appliance and the CT marker;
• attaching the imaging appliance to the human jaw;
• scanning the human jaw with the imaging appliance attached thereto to obtain the volumetric CT image of at least a portion of the fiducial and a portion of the human jaw in the volumetric CT image;
• detecting the pose of the fiducial in the volumetric CT image to derive a fiducial-to-image coordinate mapping;
• detaching the CT marker from the fixation portion to provide the fabricated appliance;
• detachably and rigidly attaching a pose-trackable tag to the fixation portion at a tag connection region to provide a tracking appliance including the fabricated appliance and the tag, wherein a configuration of the tag connection region relative to the CT marker connection region ensures a fixed tag-to-fiducial coordinate mapping prior to attaching any one of the tag and the CT marker;
• determining a tag-to-image coordinate mapping using the tag-to-fiducial coordinate mapping and the fiducial-to-image coordinate mapping;
• attaching the tracking appliance to the human jaw;
• determining a pose of the tracking appliance using a pose measurement system;
• determining tag coordinates of the selected position in a coordinate system of the tag using the pose of the tracking appliance;
• and
• mapping the tag coordinates of the selected position to a corresponding position in the volumetric CT image using the tag-to-image coordinate mapping.

A kit for mapping a selected position on or within a human jaw to a volumetric CT (computerized X-ray tomography) image of that human jaw, the kit comprising:

• a retainer appliance configured to be moldable to an appliance geometry that mates with a surface geometry of at least a portion of the human jaw, such that when mated with the human jaw, the retainer appliance resists displacement relative to the human jaw, the retainer appliance being further configured to be hardenable to remain rigid and resist deformation once molded to the appliance geometry;
• an arm comprising a moldable link portion and a rigid fixation portion, the link portion being rigidly attachable to the retainer appliance and hardenable to remain rigid and resist deformation once hardened to maintain a fixed spatial mapping between the fixation portion and the retainer appliance when the link portion is rigidly attached to the retainer appliance, the rigid fixation portion including a CT marker connection region and a tag connection region;
• a CT marker that is detachably attachable to the arm at the CT marker connection region and includes a fiducial detectable in the volumetric CT image, the fiducial shaped to allow a pose of the fiducial to be uniquely determinable in the volumetric CT image;
• and
• a tag that is detachably attachable to the arm at the tag connection region, the tag being measureable by a pose measurement system to determine a pose of the tag in a reference coordinate space;
• wherein
• a pose of the tag connection region relative to a pose of the CT marker connection region has a substantially fixed tag-to-fiducial coordinate mapping that is determinable prior to attaching any one of the tag and the CT marker.