Patent Application
20180161126
The present disclosure is related to the field of orthodontics. More specifically, the present disclosure is related to a guide for the placement of direct bonded brackets for orthodontic treatment.
Orthodontic treatments are typically employed to correct the positioning of a plurality of teeth in the patient's dentition. Orthodontic treatments are typically carried out by bonding brackets to the patient's teeth and securing an arch wire between the brackets to place corrective forces on the teeth of the patient. The brackets are typically bonded to the teeth with the use of an adhesive. Since the bonded brackets transfer the corrective forces from the arch wire to the teeth, it is important to bond the brackets to the patient's teeth in the correct positions such that the teeth are moved to the desired post-treatment positions.
In direct bonding, the orthodontist manually places each of the brackets on the teeth of the patient based upon the orthodontist's training and experience in bracket placement. Undoubtedly, it will be recognized that such a direct bonding approach may result in placement of brackets at less than an idealized position, which can result in less than optimal outcomes. Alternatively, indirect bonding approaches are available wherein a physical model of the patient's pre-treatment dentition is created and the brackets are releaseably secured to the physical model at the desired bracket placement locations. A tray is molded around the physical model and the placed brackets. After the material of the transfer tray sets, the transfer tray, otherwise known as an indirect bonding tray, incorporates the brackets and the try and brackets are removed from the physical model. Bonding material (e.g. adhesive or bonding cement is placed on the brackets in the transfer tray and the transfer tray is placed on the patient's teeth. This positions the brackets in the desired optimal positions at which the brackets are bonded to the teeth. After the bonding has set, and the tray is removed, leaving the brackets in the desired positions.
One downside to indirect bonding trays is that inherently in the bonding process extraneous bonding material placed on the side of the bracket that engages the tooth, or the pad, may necessarily exit past the bracket pad sides onto the face of the tooth not covered by the bracket pad, as the bracket is pressed into contact with the tooth. Since the indirect bonding tray surrounds the bracket and the tooth, access to the tooth and this extraneous bonding material is limited until the material is set and the tray is removed from the patient's teeth. This may make cleanup more complex and time consuming which leads to both patient and orthodontist dissatisfaction.
Therefore, embodiments of a guide tray that facilitates direct bonding placement of brackets on the teeth of patients can facilitate improved bracket placement as well as enable the cleanup of extraneous bonding cement before removal of the guide.
An exemplary embodiment of an orthodontic guide tray includes a tray surface which is at least partially congruent with a respective occlusal tooth surface. At least one opening is in a gingival direction. The at least one opening is configured to be larger that a pad of a bracket to be placed on a tooth through the opening. At least one registration feature extends from a first side of the tray surface interior opening. The at least one registration feature is configured to defined a prescribed bracket placement on the tooth. In another exemplary embodiment of an orthodontic guide tray, a tray surface is at least partially congruent with perspective occlusal, lingual, and labial tooth surfaces. A plurality of openings extends through a first side of the tray surface. Each opening of the plurality includes an occlusal side and generally opposed lateral sides. Each opening of the plurality openings opens in a gingival direction and it is configured to be larger than a pad of a bracket to be placed on a tooth through the opening. At least one registration features extends from a first side of the tray surface interior the opening. At least one registration feature is configured to define a prescribed bracket placement on a tooth.
In exemplary embodiments of the orthodontic guide tray include at least one occlusal registration feature that extends from the occlusal side interior the opening and at least one lateral registration feature that extends from one of the lateral sides interior the opening.
An exemplary embodiment of an orthodontic guide tray is made up of a plurality of tooth segments. Each of the tooth segments include an occlusal portion with a tray surface that corresponds to an occlusal surface of a tooth of a patient. The tooth segment includes a lingual portion with a ray surface corresponding to a lingual surface of the tooth and a labial portion with a tray surface corresponding to a labial surface of the tooth. An opening in the labial portion is defined by an occlusal side and generally opposed lateral sides. The opening is generally larger in a bracket pad of a bracket configured to be adhered to a tooth of a patient. At least one registration feature extends from at least one of the occlusal side and the lateral side. The at least one registration feature defines a previously determined bracket placement on a tooth.
An exemplary embodiment of an orthodontic system includes a plurality of brackets each configured to be secured at a predetermined location on a tooth of a patient. A guide tray includes a plurality of tooth segments. Each of the tooth segments includes an occlusal portion with an occlusal tray surface corresponding to an occlusal surface of a tooth of a patient. Each of the tooth segments also includes a lingual portion with a lingual tray surface corresponding to a lingual surface of the tooth and labial portion with a labial tray surface corresponding to a labial surface of the tooth. An opening in the labial portion is defined by an occlusal side and generally opposing lateral sides. The opening is generally larger than a bracket pad of a bracket of the plurality of brackets configured to be adhered to the tooth. At least one registration features extends from at least one of the occlusal side and the lateral side. The at least one registration feature defines the predetermined location on the tooth of the patient relative to the bracket to be secured at the predetermined location.
The guide tray 10 further includes an opening 20 in the guide tray 10 that defines a desired placement of the bracket pad on the tooth of the patient. In an embodiment as will be described in further detail herein, the opening 18 may represent a desired bracket placement according to a known dimension of the bracket pad 16 to which the bracket 14 is secured and further in accordance with a prescription as requested by the orthodontist. Non-limiting embodiments of orthodontic prescriptions that may be used to determine the desired bracket placement may include Roth, MBT, or Andrews prescriptions. Such prescriptions are bracket placement philosophies, guides or heuristics which provide generalized guidance as to the proper bracket positioning on patient teeth to achieve a desired post-treatment alignment.
In an alternative embodiment, the orthodontist may positionally define desired bracket placements (e.g. 3 mm from the tooth cusp and 10° of tip angulation).
The opening 18 is defined by an occlusal side 20 and generally opposed lateral sides 22. The opening 18 is generally open outwardly from the surface of the tooth and open towards the gingival side of guide tray. In an exemplary embodiment, the guide tray 10 may be configured to facilitate either lingual or labial bracket placements, however, for the purposes of description, the present disclosure will focus on vestibular bracket placement, although it will be recognized that each of the same features as described herein may be similarly applied to a guide tray for lingual side bracket placement.
The opening 18 as defined by the occlusal side 20 and lateral sides 22 enables the definition of a desired bracket placement, including both linear and angular bracket position while promoting access by the orthodontist to place the bracket, and particularly the bracket pad 16, in registration with the occlusal side 20 and lateral sides 22 in order to fix the bracket in the desired position. In an embodiment, the occlusal side 20 and lateral sides 22 are configured to abut against the sides of the bracket pad 16 in two orthogonal dimensions to define the desired position of the bracket pad to which the associated bracket 14 is secured.
Embodiments of the guide tray 10 may further include a series of perforations 24 that separate the guide tray 10 into a plurality of tooth segments 26.
In other embodiment, tray segments for individual teeth, or for groups of teeth less than the entire tray may be constructed. In embodiments, the segments may releasably secure together to form a tray, including by friction engagement of respective tabs and slots on adjacent tray segments. Exemplary embodiments are further disclosed in co-pending U.S. patent application Ser. No. 14/199,343, which is hereby incorporated by reference in its entirety.
In embodiments, the guide tray 10 is constructed exemplarily using rapid prototyping, 3D printing, or CNC milling techniques as will be described in further detail herein. In such embodiments, the guide tray may be constructed such as to be releasably secured to the patient's dentition by a friction fit between the teeth and the guide tray while in an alternative embodiment an adhesive or the like may be applied to the interior of the guide tray to facilitate temporarily securing the guide tray to the patient's teeth. In exemplary embodiments as disclosed above wherein tray segments are separable or separation features exist between tray segments, these features may facilitate removal of trays after use by separation of tray segments, including bending or breaking along separation features, including perforations.
In still further embodiments, one or more of the registration features 38, 40 may also indicate a visual alignment with one or more features of the bracket 14 or pad 16. As exemplarily shown in
As noted above, embodiments as disclosed herein, provide the registration and definition of the desired bracket placement on the tooth while also facilitating orthodontists access to the opening 32 both in the direction towards the tooth surface through the opening 32, as well as due to the lack of a gingival side to the opening 32 provided by the guide tray 30. This facilitates both orthodontist access in order to place the bracket pad in registration with the registration features 38, 40 as well as facilitates removal of the guide tray 30 without placing undue forces on the bracket or pad while the adhesive or cement may still be curing and not at maximum strength.
As seen in
The guide tray 60 defines the desired position of the bracket 16 on the tooth 12 of the patient with a registration arm 64 that extends outwardly from the guide tray 60 in a direction away from the tooth surface 48 to which the bracket pad 16 is to be secured. The registration arm 64 extends away from the guide tray 60 before extending into the interior of the opening 62 such as to maintain orthodontist access to the opening 62 to facilitate placement of the bracket on the tooth 12 of the patient. The registration arm 64 may include at least one registration feature, which may exemplarily include horizontally extending vertical registration features 66 and vertically extending horizontal registration features 68. The vertical registration features 66 define a vertical position of the bracket on the tooth 12 in the occlusal-gingival direction by abutting against a portion of the bracket 14 when that potion of the bracket 14 reaches the desired vertical position for that feature. The horizontal registration feature 68, engages the bracket 14, exemplarily in a slot 74 between generally opposed tie wings 46. The engagement between the slot 74 and the horizontal registration feature 68 ensures that the bracket 14 is positioned in a desired horizontal placement on the tooth 12. In additional embodiments, one or more of the registration features, including but not limited to horizontal registration features or vertical registration features, may be configured to engage one or more other portions of the bracket, including, but not limited to, the tie wing or wings and the arch wire slot.
It will be recognized that in alternative embodiments, combinations of the embodiments as disclosed above may be used, exemplarily to include a registration arm 64 (
The guide tray 80 assists the orthodontist in placement of the bracket on the tooth of the patient at the desired position with at least one alignment arm 82. The alignment arm 82 extends outwardly from the guide tray 60 in a direction away from the tooth surface 48 to which the bracket pad 16 was to be secured. The alignment arm 82 extends away from the guide tray 80 before extending into the interior of the opening 62. However, differing from previous embodiments, the alignment arms 82 do not contact the bracket 14 or bracket pads 16 but rather are dimensioned and/or positioned in order to align with features of the bracket when properly placed on the tooth of the patient at the desired location.
As can exemplarily be seen in
In an alternative embodiment, exemplarily depicted by the alignment arm 82 extending from the occlusal side 70, the alignment tip 84 may extend beyond the edge of the bracket pad (as best depicted in
In these exemplary embodiments, reference and guidance is provided to the orthodontist to facilitate the proper placement of the bracket on the patient's teeth according to the desired prescription. As no portion of the guide physically touches the bracket 14 and particularly the bracket pad 16, the orthodontist maintains access to the entire opening 62 to facilitate the clean-up of any extraneous bonding cement or adhesive. Furthermore, because the guide 80 is open in the gingival direction, the alignment tips 84 are distanced away from the tooth surface 48, and the alignment tips 84 minimally extend beyond the perimeter of the bracket pad, if any, the orthodontists has improved access to the opening 62 to facilitate placement of the bracket on the patient's tooth with little or no interference from the alignment arms 82. Even in embodiments wherein a portion of one or more of alignment tips 84 extend past a perimeter of the bracket pad 16, as the opening 62 is opened to gingival direction and the alignment tips 84 are spaced apart from the other surface 48, the bracket and bracket pad can be easily positioned on the tooth of the patient after the guide tray 8—has been secured to the patient's teeth.
At 102, a 3D digital model of the patient's pre-treatment dentition is obtained. In exemplary embodiments, the 3D digital model may be obtained from a digital scan of the patient's mouth or may be obtained by scanning a cast impression or physical model of the patient's teeth. The 3D digital model may be obtained in a variety of ways including, but not limited to medical imaging techniques such as computed tomography (CT), by creating a plaster cast of the patient's dentition and digitally scanning the cast, or by intraoral scanning.
This results in a 3-dimensional digital model of the patient's pre-treatment dentition. In some embodiments, as described in further detail herein, the digital design of the bonding guide may be performed using this digital model of the pre-treatment dentition. In still other embodiments, a digital set up may be created to digitally create a model of the desired post-treatment dentition of the patient.
In doing so, the pre-treatment digital model is manipulated to segment the individual teeth with in the 3D digital model. The separated teeth are digitally repositioned to reflect the desired post-treatment positions of the patient's teeth. Each of the transformations required to digitally reposition the separated teeth are recorded and saved. This creates both a record of the originally pre-treatment dentition and the transformation required by the treatment to arrive at the desired post-treatment dentition. Once the teeth have been repositioned into the post-treatment position, an arch wire lane may be positioned on the teeth and idealized bracket placements calculated therefrom. In a digital setup, once the bracket placements have been determined, the post treatment dentition is transformed back to the current pre-treatment positions of the teeth with the placed bracket. These determined bracket placements may be used in the creation of the bonding guide as disclosed herein.
In other embodiments, as found at 104, a bracket placement prescription is received. In an embodiment, the orthodontist may identify a particular prescription to be followed in determining the desired bracket placements. In non-limiting examples of commonly used prescriptions may include Roth, MBT, or Andrews prescriptions although other prescription theory and techniques will be recognized by those of ordinary skill in the art. Alternatively, the bracket placement prescription can be defined as placement relative to anatomical landmarks, exemplarily as linear distances or angles with respect to anatomical landmarks such as cusp tips, incisal edges, gingival margins, etc. The bracket placement prescription may further include an identification of whether the brackets are to be placed vestibularly or lingually.
In embodiments wherein the orthodontist provides a bracket placement prescription, if a predefined prescription, for example, a Roth, MBT, or Andrews prescription is identified, then digital version of bracket designed according to the selected prescription are selected, exemplarily from a library of digitized brackets and positioned on the teeth of the patient. Brackets in accordance with a prescription such as a Roth, MBT, or Andrews prescription may be deigned to include the tooth tilt, tip, and torque associated with that prescription, which may result in a configuration of bracket, and arch wire slot particular to that prescription. Still further, each prescription may also include a generalized preferred placement in the patient's teeth. This can be stored and used by the computer system to digitally place the selected bracket at the predefined location. As previously mentioned, in alternative embodiments, the orthodontist may specify a particular placement position on the teeth for the brackets and/or may further select the specific brackets to be used in connection with the bracket placements.
Digital models of the brackets and bracket pads to be used in the orthodontic treatment are digitally placed on the digital model of the patient's pre-treatment dentition at 106 according to the bracket placement prescription received at 104. This placement may occur in either of the manners as disclosed above, including the digital set-up and the digital application of an orthodontist prescription. Alternatively, a technician may digitally position the brackets manually. In a non-limiting embodiment, a user may be provided with the functionality to review and adjust the digital bracket placements prior to finalizing the digital placement of the brackets on the digital model of the patient's pre-treatment dentition. In one such embodiment, the digital brackets may be repositioned interactively, such as with drag and drop inputs or may be repositioned by adjusting the selected bracket or bracket placement prescription.
At 108 a guide tray is digitally designed on the pre-treatment model such that it conforms to the shape of the occlusal tooth surface and conforms to at least a portion of the lingual and labial tooth surfaces. The guide tray is digitally designed with opening and registration features as disclosed in the present application with respect to the digitally placed brackets on the digital model. In one embodiment, the guide tray is designed by defining a guide tray thickness that is consistent across the entire designed guide tray. This thickness is extended outwardly from the tooth surfaces of the digital model of the patient's pre-treatment dentition at directions perpendicular to the tooth surface. In one embodiment, the guide tray thickness is the same thickness as the pads digitally placed on the digital model, while in alternative embodiments, the guide tray thickness may be greater than or less than the pad thickness. As described above, the guide tray may be digitally designed such that brackets can be positioned lingually or labially or a combination of both bracket placements. Furthermore, the guide tray may be digitally designed at 108 such as to include a plurality of separation features, including, but not limited to perforations, perforations such that the guide tray may be separated into a plurality of smaller tooth segments.
The opening and registration features of the guide tray are digitally designed around the placed brackets. As described above, the opening is configured about the bracket pad such that the opening is generally larger than the bracket pad itself. The registration features are then designed relative to each of the place digital brackets so that the registration features of the bonding guide are specific to the selected bracket and the placement of the bracket on the patient's tooth. The registration features include any of the registration features as disclosed in the presented application, or a combination thereof. By digitally designing the openings and the registration features of the guide tray relative to the position digital brackets, the guide tray is customized to the pre-treatment dentition of the patient and the prescription provided by the orthodontist.
At 110, the digitally designed guide tray is fabricated. In embodiments, the guide tray may be fabricated using rapid prototyping, 3D printing, or CNC milling techniques, although other fabrication techniques may also be used to create the digitally designed guide tray.
In an embodiment, the fabricated guide tray may be used to assist a direct bonding placement of brackets on a patient's teeth by an orthodontist by further securing the guide tray to the patient's teeth and then placing each of the individual brackets and/or bracket pads in registration with one or more registration features of the guide tray to ensure that the bracket and bracket pads are in the desired position on the patient's tooth. Alternatively, the guide tray, once fabricated may be secured to a physical model of the patient's pre-treatment dentition, exemplarily the same physical model of the patient's pre-treatment dentition used at 102 in order to obtain the 3D digital model. Once the guide tray is secured to the physical model of the patient's pre-treatment dentition, the guide tray is used to place the brackets at the desired bracket locations and an indirect bonding tray may be formed over the physical model of the patient pre-treatment detention and the placed brackets. The indirect bonding tray may then be used by an orthodontist to place the brackets on the patient's teeth.
Embodiments of the apparatus and methods as disclosed herein enable the accurate transfer of digitally determined bracket placement positions to the physical world while providing improved visibility and accessibility to each bracket during the bonding process. This enables orthodontist's verification of proper bonding and facilitates cleanup of any extraneous bonding cement or adhesive before or after curing of the bonding cement or adhesive. In embodiments, wherein perforations separate the guide tray into a plurality of tooth segments, individual tooth segments may be used to facilitate the re-bonding or replacement of brackets that become detached from the dentition or must be replaced prior to completion of the orthodontic treatment.
The functional block diagrams, operational sequences, and flow diagrams provided in the Figures are representative of exemplary architectures, environments, and methodologies for performing novel aspects of the disclosure. While, for purposes of simplicity of explanation, the methodologies included herein may be in the form of a functional diagram, operational sequence, or flow diagram, and may be described as a series of acts, it is to be understood and appreciated that the methodologies are not limited by the order of acts, as some acts may, in accordance therewith, occur in a different order and/or concurrently with other acts from that shown and described herein. For example, those skilled in the art will understand and appreciate that a methodology can alternatively be represented as a series of interrelated states or events, such as in a state diagram. Moreover, not all acts illustrated in a methodology may be required for a novel implementation.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
The present utility application relates to and claims priority to U.S. Provisional Patent Application Ser. No. 61/916,549 filed Dec. 16, 2013, which is herein incorporated in entirety.
| Number | Date | Country | |
|---|---|---|---|
| 61916459 | Dec 2013 | US |
