US20050123876A1

US20050123876A1 - Orthodontic bracket

Info

Publication number: US20050123876A1
Application number: US10/897,587
Authority: US
Inventors: Naoki Shirasuka
Original assignee: DENT SHOJI YK
Current assignee: DENT SHOJI YK
Priority date: 2003-12-05
Filing date: 2004-07-23
Publication date: 2005-06-09
Also published as: JP4051048B2; US8215953B2; US20070048686A1; JP2005192989A

Abstract

Orthodontic brackets that can accurately be mounted to the surface of teeth to effectively perform orthodontic treatment. The orthodontic bracket according to the present invention is characterized in that, a marker is provided on at least a portion of an outline that is generated by crossing a plane including a longitudinally extending center line, on a base of an archwire slot, of the archwire slot and vertical to the base of the archwire slot, and an outer surface of the body with each other. With this bracket, coinciding the marker provided on at least a portion of the outline to the mid-transverse plane of a tooth, to which the bracket is bonded, allows the base point of the bracket to be positioned on the mid-transverse plane, further, coinciding the center of the bracket to the FACC causes the bracket to accurately be positioned on the tooth to be treated, resulting in effective orthodontic treatment. The marker can be selected from a protrusion, a projection, a slit and a notch.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates to orthodontic brackets that are easily positioned at orthodontically correct locations on the patient's teeth to effectively perform orthodontic treatment.
2. Description of the Related Art
In orthodontic treatment, orthodontic brackets made of metal or the like are bonded to the patient's teeth through bonding agent; the orthodontic brackets are fastened by a thin archwire; and an external force is applied to the orthodontic brackets through the archwire to move the teeth subjected to treatment to correct locations.
When an orthodontic bracket is bonded to the patient's tooth, as shown in FIG. 10, a vertical center line 85 of a bracket 84 should be overlapped with a facial axis of a clinical crown (hereinafter referred to as “FACC”) 81, and a center (base point) 86 b of a base 86 a of an archwire slot 86 should be coincided with a mid-transverse plane 82. If the bracket 84 is not positioned properly as described above, load of an archwire cannot be applied properly to the tooth through the bracket 84, resulting in insufficient orthodontic treatment.
In order to overlap the vertical center line of the bracket to the FACC, a variety of brackets with markers have been used. Meanwhile, in order to coincide the base point of the bracket to the mid-transverse plane of the tooth, for example, a gage partially fixed to an archwire slot of the bracket is used to bond the bracket to the tooth with the distance between the occlusal plane of the tooth and the slot being measured by the gage. However, since the base point of the bracket and the surface of the tooth are apart from each other, and manners abutting the gage to the teeth should be changed in accordance with the position of the tooth in a row of the patient's teeth, it is not easy to coincide the base point of the bracket to the mid-transverse plane of the tooth with the gage.
On the other hand, Japanese Patent Publication (Unexamined) No. Heisei 8-112293 discloses an orthodontic bracket that can be bonded to a correct position, which is parallel to the FACC and the occlusal plane. This bracket is provided with a visible standard line, which is to be parallel to the FACC, on the center line of a pair of tiewings, and another visible standard line, which is to be parallel to the occlusal plane, on a slot line crossing the former standard line. Then, orthodontists can adjust the location of the bracket while positively utilizing the standard lines.
As described above, when a bracket is mounted to a tooth, it is necessary to coincide the vertical center line of the bracket to the FACC as well as the base point to the mid-transverse. But, it is not easy to do so with the above-mentioned gage. With the bracket shown in the above document, standard lines are provided on the center line of a pair of tiewings and on the slot line only, so that it is not easy to coincide the base point of the bracket and the mid-transverse plane of the tooth with each other.
Especially, as illustrated in FIG. 11, when a torque-in-face-type bracket is used, in order to coincide a base point 98 of a bracket 90 to a mid-transverse plane 92 of a tooth 96 to be treated, it is necessary to coincide a target point 100 that is generated by crossing a line, which passes the base point 98 of the bracket 90 and vertical to a base 91 a of an archwire slot 91, and a base 99 a of a body 99, to a facial-axis point (hereinafter referred to as “FA point”) 94 where the FACC of the tooth 96 and the mid-transverse plane 92 cross with each other. However, since the target point 100 and a center 99 b of the base 99 a of the body 99 are remarkably apart from each other, it is not easy to coincide the target point 100 of the bracket 90 to the FA point 94, in its turn, it is not easy to coincide the base point 98 of the bracket 90 to the mid-transverse plane 92 of the tooth 96.

SUMMARY OF THE INVENTION

It is therefor the object of the present invention to provide brackets in which a vertical center line of the bracket can easily be coincided to the FACC, and the base point of the bracket can easily be coincided to the mid-transverse plane, resulting in effective orthodontic treatment.
To accomplish the above objective, an orthodontic bracket according to the present invention is characterized in that, a marker is provided on at least a portion of an outline that is generated by crossing a plane including a longitudinally extending center line, on a base of an archwire slot, of the archwire slot and vertical to the base of the archwire slot, and an outer surface of the body with each other.
With the above orthodontic bracket according to the present invention, coinciding the marker provided on at least a portion of the outline to the mid-transverse plane of a tooth, to which the bracket is bonded, allows the base point of the bracket to be positioned on the mid-transverse plane, further, coinciding the center of the bracket to the FACC causes the bracket to accurately be positioned on the tooth to be treated, resulting in effective orthodontic treatment.
In the afore-mentioned bracket according to the present invention, the marker may be selected from a protrusion, a projection, a slit and a notch.
Further, an orthodontic bracket according to the present invention is characterized in that, a through hole penetrates a body from a base of the body to an outer surface of the bracket along a line passing through a point that is generated by crossing a line, which is generated by crossing a plane including a longitudinally extending center line, on a base of an archwire slot, of the archwire slot and vertical to the base of the archwire slot, and the base of the body, and a plane vertical to the center line of the archwire slot and dividing the body exactly into two parts.
With the above orthodontic bracket according to the present invention, using a needle-like jig, the FA point of the tooth to be treated and the target point for positioning of the bracket can directly be coincided with each other, which is effective especially in indirect method, in which a bracket is preliminarily bonded on a model of the patient's row of teeth at a position where the bracket should be mounted, and then, the bracket is properly transported in the oral cavity of the patient and is bonded to the patient's tooth.
The orthodontic bracket described above may further comprises a marker provided on at least a portion of an outline that is generated by crossing the plane including the longitudinally extending center line, on the base of the archwire slot, of the archwire slot and vertical to the base of the archwire slot, and an outer surface of the body with each other. With this construction, directly coinciding the FA point of the tooth to be treated and the target point for positioning of the bracket with each other, and further coinciding the marker to the mid-transverse plane of the tooth, to which the brackets is mounted, causes the bracket to remarkably accurately be positioned on the tooth to be treated with ease. And, the marker can be selected from a protrusion, a projection, a slit and a notch.
Still further, an orthodontic bracket according to the present invention is characterized in that, one of a projection and a concave portion is provided at a point that is generated by crossing a line, which is generated by crossing a plane including a longitudinally extending center line, on a base of an archwire slot, of the archwire slot and vertical to the base of the archwire slot, and the base of the body, and a plane vertical to the center line of the archwire slot and dividing the body exactly into two parts.
With the above orthodontic bracket according to the present invention, engaging the projection or the concave portion at the target point of the base of the body to the concave portion or the projection, which is formed on the FA point of the tooth to be treated in advance, allows the FA point of the tooth to be treated and the target point for positioning of the bracket to directly be coincided with each other, which especially effective in indirect orthodontic treatment.
The orthodontic bracket described above may further comprises a marker provided on at least a portion of an outline that is generated by crossing the plane including the longitudinally extending center line, on the base of the archwire slot, of the archwire slot and vertical to the base of the archwire slot, and an outer surface of the body with each other. With this construction, directly coinciding the FA point of the tooth to be treated and the target point for positioning of the bracket with each other, and further coinciding the marker to the mid-transverse plane of the tooth, to which the brackets is mounted, causes the bracket to remarkably accurately be positioned on the tooth to be treated with ease. And, the marker can be selected from a protrusion, a projection, a slit and a notch.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be more apparent from the ensuring description with reference to the drawings, wherein:
FIGS. 1A to 1C show an orthodontic bracket according to the first embodiment of the present invention, in which FIG. 1A is a front view, FIG. 1B a plan view and FIG. 1C a side view;
FIG. 2 is a perspective view of the orthodontic bracket shown in FIGS. 1A to 1C;
FIGS. 3A to 3C are drawings for explaining a manner to mount the bracket shown in FIGS. 1A to 1C to a tooth, in which FIG. 3A is for explaining a standard line and a standard point of the tooth, FIG. 3B is a plan view for explaining the manner to mount the bracket to the tooth, and FIG. 3C is a side view of the bracket and the tooth shown in FIG. 3B;
FIGS. 4A to 4C show an orthodontic bracket according to the second embodiment of the present invention, in which FIG. 4A is a front view, FIG. 4B a plan view and FIG. 4C a side view;
FIG. 5 is a drawing for explaining the usage of the bracket shown in FIGS. 4A to 4C;
FIGS. 6A to 6C show an orthodontic bracket according to the third embodiment of the present invention, in which FIG. 6A is a front view, FIG. 6B a plan view and FIG. 6C a side view;
FIG. 7 is a drawing for explaining the usage of the bracket shown in FIGS. 6A to 6C;
FIGS. 8A to 8C show an orthodontic bracket according to the forth embodiment of the present invention, in which FIG. 8A is a front view, FIG. 8B a plan view and FIG. 8C a side view;
FIG. 9 is a drawing for explaining the usage of the bracket shown in FIGS. 8A to 8C;
FIGS. 10A to 10D are drawings for explaining a manner to mount a conventional bracket to a tooth, in which FIG. 10A is for explaining a standard line and a standard point of the tooth, FIG. 10B is a plan view for explaining the manner to mount the bracket to the tooth, FIG. 10C is a side view of the bracket and the tooth shown in FIG. 10B, and FIG. 10D is an enlarged view showing the bracket on the tooth; and
FIG. 11 is a schematic view for explaining a manner to mount a conventional torque-in-face-type bracket to a tooth.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Now, preferred embodiments of the present invention will be explained with reference to drawings.
FIGS. 1A to 1C and FIG. 2 show an orthodontic bracket according to the first embodiment of the present invention. This bracket 1 is provided with tiewings 3 (3A, 3B) and archwire slots (hereinafter referred to as “slots”) 4 (4A, 4B) on a body 2, and the bases 4 a of the slots 4 and the base 2 a of the body 2 are parallel with each other, that is, a standard bracket. The body 2 includes a pad portion, which is the same in other embodiments described below.
The first slit 5 as a marker is formed along an outline generated by crossing a plane including a center 2 b of a base 2 a of the body 2 of the bracket 1 and vertical to a longitudinal direction of the slot, and the outer surface of the body 2. The marker of the first slit 5 is used to coincide a vertical center line of the bracket 1 to the FACC of a tooth. This marker is the same as formed in conventional brackets.
In addition to the first slit 5, the second slits 6 (6A, 6B) as markers are formed along an outline generated by crossing a plane including a longitudinally extending center line 4 b, on the base 4 a of the archwire slot 4, of the archwire slot 4 and vertical to the base 4 a of the archwire slot 4, and the outer surface of the body 2 with each other, and along a line connecting ends of the outline and ends of the center lines 4 b of the slots 4 with each other on rising portions of the tiewings 3. The markers of the second slits 6 are a special character of the present invention, and are used to coincide these slits 6 to the mid-transverse plane of a tooth to accurately coincide the base point 4 c of the bracket 1 to the mid-transverse plane of the tooth.
Next, the usage of the bracket 1 will be explained with reference to FIGS. 3A to 3C. In these figures, the tooth 10 is illustrated without any angulations and torque as a matter of convenience.
When the bracket 1 is mounted to the tooth 10, it is necessary to coincide the vertical center line of the bracket 1 to the FACC 11 of the tooth 10, and the base point 4 c of the bracket 1 to the mid-transverse plane 12 of the tooth. Therefore, as illustrated in FIG. 3B, with the eyes, the first slit 5 of the bracket 1 is overlapped to the FACC 11, and the second slits 6 (6A, 6B) are coincided to the mid-transverse plane 12 of the tooth, which allows the bracket 1 to accurately be bonded to a proper position of the tooth 10 with ease. As a result, the orthodontic treatment can effectively be carried out.
Next, the second embodiment of the present invention, in which the so-called torque-in-face-type bracket is used, will be explained with reference to FIGS. 4A to 4C and FIG. 5.
The torque-in-face-type bracket is, as shown in FIGS. 4C and 5, characterized in that the bracket 21 is provided with tiewings 23 (23A, 23B); bases 24 a of slots 24 (24A, 24B) and a base 22 a of a body 22 are not parallel with each other; and a plane including a longitudinally extending center line 24 b, on the base 24 a of the archwire slot 24, of the archwire slot 24 and vertical to the base 24 a of the archwire slot 24 does not pass through the center 22 b of the base 22 a of the body 22. Therefore, as shown in FIG. 11, the target point 100 of the bracket 90, which should be coincided with the FA point 94 of the tooth 96, and the center 99 b of the base 99 a of the body 99 are remarkably apart from each other, so that it is not easy to coincide the base point 98 of the bracket 90 to the a mid-transverse plane 92 of the tooth 96.
With the bracket 21 of the present invention, in addition to the first slit 25 like the first slit 5 in the above first embodiment, the second slits 26 (26A, 26B) as markers are formed along an outline that is generated by crossing a plane including the longitudinally extending center line 24 b, on the base 24 a of the archwire slot 24, of the archwire slot 24 and vertical to the base 24 a of the archwire slot 24, and an outer surface of the body 22 with each other, so that, as shown in FIG. 5, coinciding end portions 26 a of the slits 26 situated at edge portions of the body 22 to the mid-transverse plane 38 of the tooth 39 allows the base point 24 c of the bracket 21 to be coincided to the mid-transverse plane 38 of the tooth 39, resulting in effective orthodontic treatment.
Next, the third embodiment of the present invention, in which the so-called torque-in-base-type bracket is used, will be explained with reference to FIGS. 6A to 6C and FIG. 7.
The torque-in-base-type bracket is, as shown in FIGS. 6C and 7, characterized in that the bracket 41 is provided with tiewings 43 (43A, 43B); bases 44 a of slots 44 (44A, 44B) and a base 42 a of a body 42 are not parallel with each other; and a plane including a longitudinally extending center line 44 b, on the base 44 a of the archwire slot 44, of the archwire slot 44 and vertical to the base 44 a of the archwire slot 44 passes through the center 42 b of the base 42 a of the body 42.
With this bracket 41 of the present invention, in addition to the first slit 45 like the first slit 5 in the above first embodiment, the second slits 46 (46A, 46B) as markers are formed along an outline that is generated by crossing a plane including the longitudinally extending center line 44 b, on the base 44 a of the archwire slot 44, of the archwire slot 44 and vertical to the base 44 a of the archwire slot 44, and an outer surface of the body 42 with each other, so that, as shown in FIG. 7, coinciding end portions 46 a of the slits 46 situated at edge portions of the body 42 to the mid-transverse plane 58 of the tooth 59 allows the base point 44 c of the bracket 41 to be coincided to the mid-transverse plane 58 of the tooth 59, resulting in effective orthodontic treatment.
The slits 5, 6, 25, 26, 45 and 46 as markers should not be formed on the overall outlines, but those may be placed near the edge portions only. Further, the markers are not limited to slits, but protrusions, projections and notches may be used. Besides the slits 5, 6, 25, 26, 45 and 46 as markers, which are obtained by directly machining brackets, markers painted on the outer surface of brackets, which are utilized to position the brackets and are rubbed out after the positioning, may be included in the scope of this invention.
In addition, not only markers for positioning directly applied to brackets as described above, but also a jig mounted to a slot of a bracket and functioning, with a part of the jig, in the same manner as the slit or the like on at least a portion of the outline may be included in the scope of the present invention.
Next, the forth embodiment of the present invention, which is especially suitable for the indirect boding method, will be explained. In this method, a bracket is preliminarily bonded on a model of the patient's row of teeth at a position where the bracket should be mounted, and then, the bracket is properly transported in the oral cavity of the patient and bonded to the patient's tooth.
As illustrated in FIGS. 8A to 8C, the bracket 61 is constructed such that a through hole 62 is drilled so as to penetrate the body 22 from the base 22 a of the body 22 to the outer surface of the bracket 61 along a line passing through a point (target point) 27 that is generated by crossing a line, which is generated by crossing a plane including the longitudinally extending center line 24 b, on the base 24 a of the archwire slot 24, of the archwire slot 24 and vertical to the base 24 a of the archwire slot 24, and the base 22 a of the body 22, and a plane vertical to the center line 24 b of the archwire slot 24 and dividing the body 22 exactly into two parts.
To use this bracket 61, as shown in FIG. 9, a needle-like jig 71 is inserted into the through hole 62 of the bracket 61, and the tip of the jig 71 is fixed to an FA point 73, which is marked in advance on a tooth 74 on a model of a row of teeth to position the target point 27 on the base 22 a of the body 22, and then, as described above, the second slits 26 of the bracket 61 and the mid-transverse plane 38 of the tooth 74 are coincided with each other to position the bracket 61 to the tooth 74. After that, with the transfer tray, registered in Japanese Utility Model No. 3097069 by the present applicant, or the like, the bracket 61 is accurately positioned on the patient's tooth with ease.
Although, in the fourth embodiment described above, the through hole 62 is drilled on the body of the torque-in-face-type bracket 21, the through hole 62 may be applied to the standard bracket shown in FIGS. 1A to 1C and FIG. 2, and the torque-in-base-type bracket 41 shown in FIGS. 6A to 6C. Further, in the above-mentioned embodiments, after the through hole 62 is positioned with the jig 71, the second slits 26 and the mid-transverse plane 38 are coincided with each other to properly position the bracket 61 to the outer surface of the tooth 74. Without the second slits 26, the bracket 61 can properly be positioned on the outer surface of the tooth by coinciding the center of the bracket and the FACC with each other in the same manner as a conventional method.
Still further, in the fourth embodiment, the through hole 62 is formed to the bracket 61. In place of the through hole 62, a projection or a concave portion can be provided at the target point 27 of the bracket 61, and then engaging one of them to a concave portion or a projection formed at the FA point 73 of the tooth 74 in a row of teeth in advance allows the target point 27 to directly be coincided with the marked FA point 73. In this case, the cross-sectional shape of the projection or the concave portion formed at the target point 27 of the base 22 of the bracket 61, and the cross-sectional shape of the concave portion or the projection formed at the FA point 73 of the tooth 74 are not limited to round, but the shape may be rectangular or triangular. Further, these projections or concave portions are not required to be formed at the production of the bracket 61 or tooth in a row of teeth, but in the indirect boding method, it is sufficient to form the projections or concave portions before the bracket is preliminarily bonded on a model of the patient's row of teeth at a position where the bracket should be mounted.
The above-mentioned brackets according to the present invention are applicable to all kinds of teeth including true molar teeth, and the present invention is applicable to brackets mounted on the tongue side also.

Claims

1. An orthodontic bracket characterized in that, a marker is provided on at least a portion of an outline that is generated by crossing a plane including a longitudinally extending center line, on a base of an archwire slot, of said archwire slot and vertical to the base of the archwire slot, and an outer surface of the body with each other.

2. The orthodontic bracket as claimed in claim 1, wherein said marker is selected from a protrusion, a projection, a slit and a notch.

3. An orthodontic bracket characterized in that, a through hole penetrates a body from a base of said body to an outer surface of said bracket along a line passing through a point that is generated by crossing a line, which is generated by crossing a plane including a longitudinally extending center line, on a base of an archwire slot, of said archwire slot and vertical to the base of the archwire slot, and the base of the body, and a plane vertical to the center line of the archwire slot and dividing the body exactly into two parts.

4. The orthodontic bracket as claimed in claim 3, further comprising a marker provided on at least a portion of an outline that is generated by crossing the plane including the longitudinally extending center line, on the base of the archwire slot, of the archwire slot and vertical to the base of the archwire slot, and an outer surface of the body with each other.

5. The orthodontic bracket as claimed in claim 4, wherein said marker is selected from a protrusion, a projection, a slit and a notch.

6. An orthodontic bracket characterized in that, one of a projection and a concave portion is provided at a point that is generated by crossing a line, which is generated by crossing a plane including a longitudinally extending center line, on a base of an archwire slot, of said archwire slot and vertical to the base of the archwire slot, and the base of the body, and a plane vertical to the center line of the archwire slot and dividing the body exactly into two parts.

7. The orthodontic bracket as claimed in claim 6, further comprising a marker provided on at least a portion of an outline that is generated by crossing the plane including the longitudinally extending center line, on the base of the archwire slot, of the archwire slot and vertical to the base of the archwire slot, and an outer surface of the body with each other.

8. The orthodontic bracket as claimed in claim 7, wherein said marker is selected from a protrusion, a projection, a slit and a notch.