STENT, A REPRODUCING METHOD USING THE STENT, AND A METHOD FOR POSITIONING A WIRE

• US 20110143307A1
• Filed: 03/24/2009
• Published: 06/16/2011
• Est. Priority Date: 03/27/2008
• Status: Abandoned Application

• Current Assignee: Akira Takebayashi
• Original Assignee: Akira Takebayashi
• Inventors: Takebayashi, Akira
• Application Number:
  US12/922,920
• Publication Number:
  US 20110143307A1
• Time in Patent Office: Days
• US Class Current: 433/74
• CPC Class Codes: A61B 6/03 Computed tomography [CT] echo-tomography A61B8/14
• CPC Class Codes: A61B 6/12 Arrangements for detecting or locating foreign bodies
• CPC Class Codes: A61B 6/51 for dentistry
• CPC Class Codes: A61C 1/084 of implanting tools
• CPC Class Codes: A61C 11/00 Dental articulators, i.e. for simulating movement of the temporo-mandibular joints; Articulation forms or mouldings
• CPC Class Codes: A61C 8/00 Means to be fixed to the jaw-bone for consolidating natural teeth or for fixing dental prostheses thereon; Dental implants; Implanting tools fastening of peg-teeth in the mouth A61C13/30

Abstract

Provided is a stent used when a wire that indicates the position and orientation a fixture is to be embedded at on a mockup for creating an anatomically and prosthetically appropriate and highly accurate surgical guide.

The stent includes a detachably attachable guide member 1 that includes a fitting portion 2 to be fitted to a tooth portion of the mockup and an actual tooth portion of a patient corresponding to the tooth portion of the mockup, and a covering portion 3 covering a mucosa surface 44 at the portion a tooth is missing; a first positioning member 10 including at least a planar first contrast medium 11 for CT scanner and mounted to the covering portion 3; and a second positioning member 20 including at least a planar second contrast medium 21, the member 20 opposing to the first contrast medium 11 and detachably attachable to the member 10.

Claims

1. A stent used for positioning a wire that indicates the position and orientation a dental implant fixture is to be embedded at when the wire is embedded in an upper jaw mockup or a lower jaw mockup, the mockup imitating inside of the mouth of a patient, the stent comprising:

a detachably attachable guide member that includes a fitting portion to be fitted to a tooth portion of the mockup and to an actual tooth portion of the patient that corresponds to the tooth portion of the mockup, and a covering portion that covers a mucosa surface at a portion a tooth is missing;

a first positioning member including at least a planar first contrast medium for a CT scanner and mounted to the covering portion; and

a second positioning member including at least a planar second contrast medium for the CT scanner, the second positioning member opposing to the first contrast medium and being detachably attachable to the first positioning member.

2. The stent according to claim 1 characterized in that the first contrast medium and the second contrast medium are disposed in substantially parallel to each other.

3. The stent according to claim 1, comprising:

first positioning references formed by removing a portion of the first contrast medium, and

second positioning references formed by removing a portion of the second contrast medium.

4. The stent according to claim 3 characterized in that:

the second positioning member includes two pole-like spacers embedded therein facing toward the first positioning member, and

the first positioning member includes engaging holes with which the tip of the spacers are engaged, and

the second positioning references are formed at portions corresponding to base end portions of the two spacers, and

the first positioning references are formed at portions corresponding to the engaging holes.

5. The stent according to claim 1 characterized in that a planar third contrast medium is provided in the covering portion of the guide member at a portion that contacts the mucosa surface.

6. The stent according to claim 2 characterized in that the stent comprises a planar reference plate for positioning a CT scanner, the reference plate being mounted to the guide member in substantially parallel to the first contrast medium and the second contrast medium, and protruding outward from the mouth of the patient when the guide member is fitted to the tooth portion of the patient.

7. The stent according to claim 1 characterized in that an X-ray absorber is provided in the fitting portion of the guide member or on a surface of the fitting portion.

8. The stent according to claim 1 characterized in that grid-like scales are provided to the first contrast medium and the second contrast medium, and the contrast medium at the portions of the scales is removed.

9. The stent according to claim 1 characterized in that a multiple of small holes are provided in a grid-like pattern to the first contrast medium and the second contrast medium, and the contrast medium at the portions of the small holes is removed.

10. A method for reproducing on a CT scanner display the position and orientation of a fixture to be embedded at on a mockup that imitates inside of the mouth of a patient, the method using a stent that includes a detachably attachable guide member that includes a fitting portion to be fitted to a tooth portion of the mockup and to an actual tooth portion of the patient that corresponds to the tooth portion of the mockup, and a covering portion that covers a mucosa surface at a portion a tooth is missing;

a first positioning member including at least a planar first contrast medium for a CT scanner and mounted to the covering portion; and

a second positioning member including at least a planar second contrast medium for the CT scanner, the second positioning member opposing to the first contrast medium and being detachably attachable to the first positioning member, the method comprising;

(1) a wax-up hole forming step in which an upper jaw mockup and a lower jaw mockup are mounted to an articulator, and wax-up for the missing tooth is performed on the mucosa surface of the mockup, and a first through-hole is formed at the position and orientation the fixture should be embedded, in the tooth for which wax-up is performed,

(2) an irradiating step for irradiating the center of the first through-hole by a light beam from a pointer movably supported by a supporting member, a base end portion of the supporting member being mounted to the mockup,

(3) a positioning reference forming step for forming first positioning references by removing a portion of the first contrast medium, and forming second positioning references by removing a portion of the second contrast medium,

(4) a second positioning step in which the tooth for which wax-up is performed is removed from the mockup, and the stent is mounted to the mockup, and a second removed portion is formed by removing a portion, which is irradiated by the light beam, of the second contrast medium in the second positioning member of the stent,

(5) a first positioning step for forming a first removed portion by removing a portion, which is irradiated by the light beam, of the first contrast medium in the first positioning member,

(6) an imaging step in which the stent is removed from the mockup, and the stent is fitted to the tooth portion of the patient and CT scanning is performed, and

(7) a simulation step for simulating on the CT scanner display a virtual embedding hole of the fixture, along an extended line of a straight line that connects the first removed portion and the second removed portion.

11. A reproducing method for reproducing on a mockup the position and orientation of a fixture to be embedded at on a CT scanner display, the mockup imitating inside of the mouth of a patient, the method using a stent that includes a detachably attachable guide member that includes a fitting portion to be fitted to a tooth portion of the mockup and to an actual tooth portion of the patient that corresponds to the tooth portion of the mockup, and a covering portion that covers a mucosa surface at a portion a tooth is missing;

a first positioning member including at least a planar first contrast medium for a CT scanner and mounted to the covering portion; and

a second positioning member including at least a planar second contrast medium for the CT scanner, the second positioning member opposing to the first contrast medium and being detachably attachable to the first positioning member, the reproducing method comprising;

(8) a modifying step for modifying a virtual embedding hole on the CT scanner display, based on the internal structure of the jaw bone of the patient,

(9) an intersection point determining step for obtaining a first intersection point and a second intersection point on the display, the intersection points being the points at which the center line of the modified virtual embedding hole of the fixture intersects the first contrast medium and the second contrast medium,

(10) a coordinate reading step for reading on the display the coordinate of the first intersection point with respect to the first positioning references and the coordinate of the second intersection point with respect to the second positioning references,

(11) a drawing step for drawing the first intersection point and the second intersection point onto the first contrast medium and the second contrast medium of the stent, based on the read coordinates,

(12) a marking step for putting a mark at the first intersection point drawn on the first contrast medium,

(13) a second through-hole forming step for forming a second through-hole at the second intersection point drawn on the second contrast medium, and

(14) a pointer positioning step in which the stent is mounted to the mockup, and a pointer is fixed to the mounted stent at a position such that the light beam from the pointer, which passes through the second through-hole, irradiates the mark.

12. A positioning method for positioning a wire that indicates the position and orientation a dental implant fixture is to be embedded at when the wire is embedded in the mockup, the method using a stent that includes a detachably attachable guide member that includes a fitting portion to be fitted to a tooth portion of a mockup that imitates inside of the mouth of a patient and to an actual tooth portion of the patient that corresponds to the tooth portion of the mockup, and a covering portion that covers a mucosa surface at a portion a tooth is missing;

a first positioning member including at least a planar first contrast medium for a CT scanner and mounted to the covering portion; and

a second positioning member including at least a planar second contrast medium for the CT scanner, the second positioning member opposing to the first contrast medium and being detachably attachable to the first positioning member, the positioning method comprising;

(1) a wax-up hole forming step in which an upper jaw mockup and a lower jaw mockup are mounted to an articulator, and wax-up for the missing tooth is performed on the mucosa surface of the mockup, and a first through-hole is formed at the position and orientation the fixture should be embedded, in the tooth for which wax-up is performed,

(2) an irradiating step for irradiating the center of the first through-hole by a light beam from a pointer movably supported by a supporting member, a base end portion of the supporting member being mounted to the mockup,

(3) a positioning reference forming step for forming first positioning references by removing a portion of the first contrast medium, and forming second positioning references by removing a portion of the second contrast medium,

(4) a second positioning step in which the tooth for which wax-up is performed is removed from the mockup, and the stent is mounted to the mockup, and a second removed portion is formed by removing a portion, which is irradiated by the light beam, of the second contrast medium in the second positioning member of the stent,

(5) a first positioning step for forming a first removed portion by removing a portion, which is irradiated by the light beam, of the first contrast medium in the first positioning member,

(6) an imaging step in which the stent is removed from the mockup, and the stent is fitted to the tooth portion of the patient and CT scanning is performed,

(7) a simulation step for simulating on the CT scanner display a virtual embedding hole of the fixture, along an extended line of a straight line that connects the first removed portion and the second removed portion,

(8) a modifying step for modifying the virtual embedding hole on the CT scanner display, based on the internal structure of the jaw bone of the patient,

(9) an intersection point determining step for obtaining a first intersection point and a second intersection point on the display, the first and second intersection points being the points at which the center line of the modified virtual embedding hole of the fixture intersects the first contrast medium and the second contrast medium,

(10) a coordinate reading step for reading on the display the coordinate of the first intersection point with respect to the first positioning references and the coordinate of the second intersection point with respect to the second positioning references,

(11) a drawing step for drawing the first intersection point and the second intersection point onto the first contrast medium and the second contrast medium of the stent, based on the read coordinates,

(12) a marking step for putting a mark at the first intersection point drawn on the first contrast medium,

(13) a second through-hole forming step for forming a second through-hole at the second intersection point drawn on the second contrast medium,

(14) a pointer positioning step in which the stent is mounted to the mockup, and a pointer is fixed to the mounted stent at a position such that the light beam from the pointer, which passes through the second through-hole, irradiates the mark,

(15) an embedding hole forming step in which the stent is removed, and an embedding hole is formed in the mockup, along the light beam from the pointer, and

(16) an embedding step in which a wire is embedded in the embedding hole.