Endodontic therapy system, apparatus and method making use of a disposable CT registration tray device with pre-set radiographic registration markers

Abstract

A system for endodontic therapy includes a radio-opaque tray having three or more fiduciary markers embedded in the tray, a leveling device, and one or more bite stops arranged to ensure maintenance of adequate bite registration or impression material between opposing teeth to allow 3D reconstruction of occlusal surfaces.

Claims

1. A system for endodontic therapy, the system comprising: a scanning appliance including a radio-opaque tray including three or more fiduciary markers embedded in the tray, a leveling device arranged to limit a height of an artifacted coronal zone, and one or more bite stops, and a virtual endodontic treatment plan including a scan of the scanning appliance and at least one access path to a root canal, the bite stops arranged to ensure maintenance of adequate bite registration or impression material between opposing teeth.

2. A system according to claim 1 wherein the three or more fiduciary markers are located on an inside or outside surface of the tray.

3. A system according to claim 1 wherein each fiduciary marker, the leveling device, and the one or more bite stops do not artifact or appear on a scanned image.

4. A system according to claim 1 wherein the leveling device is a bubble.

5. A system according to claim 1 further comprising an aiming device arranged to show a boundary of a canal volume.

6. A system for endodontic therapy, the system comprising: a scanning appliance including a radio-opaque tray including three or more fiduciary markers embedded in the tray, a leveling device, and one or more bite stops; a virtual endodontic treatment plan including a scan of the scanning appliance and at least one access path to a root canal; and an aiming device arranged to provide a starting point to a canal orifice in an axial plane and elongate each of those starting points as lines in X and Y-slice angles to form the access path, the bite stops arranged to ensure maintenance of adequate bite registration or impression material between opposing teeth.

7. A system according to claim 6 wherein the three or more fiduciary markers are located on an inside or outside surface of the tray.

8. A system according to claim 6 wherein each fiduciary marker, the leveling device, and the one or more bite stops do not artifact or appear on a scanned image.

9. A system according to claim 6 wherein the leveling device is a bubble.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1A is a front view of a preferred embodiment of a scanning appliance in virtual space relative to the root canal system of tooth #18 (segmented using MIMICS® software for medical image processing (Materialise, Belguim)).

(2) FIG. 1B is an isometric view of the scanning appliance relative to FIG. 1A.

(3) FIG. 2A is a view of the scanning appliance of FIG. 1A showing the access path to DB canal orifice, with the treatment-planned virtually, to enter each root canal at an ideal angle (see also FIGS. 2B to 2D).

(4) FIG. 2B is a view of the scanning appliance of FIG. 1A showing the access path to DL canal orifice.

(5) FIG. 2C is a view of the scanning appliance of FIG. 1A showing the access path to MB canal orifice.

(6) FIG. 2D is a view of the scanning appliance of FIG. 1A showing the access path to ML canal orifice.

(7) FIG. 3A is a view of the scanning appliance of FIG. 1A showing four minimally invasive access paths to each of the root canals (see also FIGS. 2A to 2D).

(8) FIG. 3B shows the underside of the scanning appliance of FIG. 1A, showing the access paths seen in FIG. 3A intersecting the occlusal surface of tooth #1.

ELEMENTS AND NUMBERING USED IN THE DRAWING FIGURES

(9) 101 Disposable CT Registration Tray 102 Registration markers 103 Tray handle 104 Leveling bubble 105 Bite stop 106 Syringed bite registration or impression material in tray 107 Cross-section of disposable CT registration tray between opposing teeth embedded in bite-registration or impression material

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(10) The current method using prior art systems and apparatuses is shown in Table 1.

(11) TABLE-US-00001 TABLE 1 Prior Art Method. Dentist Dental Lab 1. Perform a CT scan 2. Take upper and lower impressions 3. Send the impressions to a lab 4. Pour impressions, and separate, grind, and articulate model 5. Design and fabricate acrylic scanning appliance with fiduciary markers 6. Take second CT scan with the scanning appliance in the patient's mouth (the first scan is needed to diagnose the case before CT-GES treatment planning can be considered)
Using the system and apparatuses of this invention, the prior art method is replaced by a single scan of a bite registration tray when in the patient's mouth. The turn-around time from first imaging to perfect access is at least halved, costs are at least halved and, because of the quick turn-around time and lower cost, CT-guided implant surgery is encouraged.

(12) Because coronal structures cannot be seen with CT, this data must be captured by other means to have a full and accurate computer model of the crowns of teeth as those crowns relate to root structures (which can be seen on a CT). If the impression material chosen for the CT scan is radio-opaque, the dental lab procedure currently needed to create a scan appliance can be eliminated. In effect, the CT-leveling bite-plane provided by the bite registration tray of this invention is the CT scanning appliance.

(13) First, the bite registration tray is inserted into a tab on a level-scan device of a kind typically used for CT scanning. Second, one or both sides of the tray is loaded with bite registration paste (or covers are peeled off which expose pre-placed bite registration paste). Third, the patient is guided to close his or her teeth into the registration paste with the mandible set in centric position (the mandibular condyles are moved to their mid-most, rear-most, and upper-most position in the joint space). This provides impressions of the occlusal surfaces. Those impressions are the only ones needed to make drill guides for implants and endodontic access. Impressions of the sides or gingival contours are not needed.

(14) A registration tool aligns, using at least three and preferably up to nine fiduciary markers or points, the first CT-scan data set (patient with scanning appliance in place) and the second CT-scan data set (scanning appliance only). The fiduciary markers are any radio-opaque material preferable, including but not limited to gutta percha.

(15) A snap-line tool attaches a starting point to each canal orifice in the axial plane, and then allows each of those points to be elongated as lines in the X and Y-slice angles to provide ideal access entry paths. The drill guide design is aided through software that locates the guide ring on the outside of the drill guide—an exact distance from the final length of the drill—so the Z-plane can be controlled as well.

(16) Software suitable for i-Dixel CT-GEA registration and treatment planning permits a clinician to CT-capture a patient's jaw with the scanning appliance in place, scan the appliance separately, register the two datasets, treatment plan the access path or paths, and email the access path plan to a local digital dental lab which sets up and 3-D prints the needed drill guides.