WO2001080764A1 - Systems and methods for varying elastic modulus appliances - Google Patents
Systems and methods for varying elastic modulus appliances Download PDFInfo
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- WO2001080764A1 WO2001080764A1 PCT/US2001/013217 US0113217W WO0180764A1 WO 2001080764 A1 WO2001080764 A1 WO 2001080764A1 US 0113217 W US0113217 W US 0113217W WO 0180764 A1 WO0180764 A1 WO 0180764A1
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
- A61C7/00—Orthodontics, i.e. obtaining or maintaining the desired position of teeth, e.g. by straightening, evening, regulating, separating, or by correcting malocclusions
- A61C7/08—Mouthpiece-type retainers or positioners, e.g. for both the lower and upper arch
Definitions
- This invention relates in general to a method of repositioning teeth for use in orthodontic treatment. Particularly, this invention relates to the use of orthodontic appliances for producing tooth movements. More particularly, this invention relates to the use of a plurality of elastic repositioning appliances for producing such tooth movements.
- Orthodontic treatments involve repositioning misaligned teeth and improving bite configurations for improved cosmetic appearance and dental function. Repositioning teeth is accomplished by applying controlled forces to the teeth over an extended period of time. This is conventionally accomplished by wearing what are commonly referred to as "braces.” Braces comprise a variety of appliances such as brackets, bands, archwires, ligatures, and O-rings.
- polymeric positioning appliances are generally transparent, providing an improved cosmetic appearance, and impart substantial force on the teeth, due to stiffness of the appliance.
- the stiffness of an elastic positioning appliance is a result of the modulus of the thermoformable polymer materials from which it is made. The higher the modulus of the materials, the higher the stiffness of the appliance.
- the stiffer the appliance the more difficult it is to slip the misaligned appliance over the teeth and fully engage the appropriate surfaces; the appliance often has the tendency to disengage or "pop off.
- a stiff appliance is less forgiving in cases of lowered patient compliance. If a patient were to remove the appliance for an unprescribed period of treatment time, the patient's teeth may move slightly out of the planned tooth arrangement. When attempting to reapply the appliance, it may be too rigid to accommodate these slight differences and a new appliance may need to be created.
- the tooth positions defined by the cavities in each successive appliance must not differ beyond a limiting dimension from those defined by the prior appliance or, again, it may be too rigid to accommodate the differences.
- Repositioning is accomplished with a system comprising a series of polymeric appliances configured to receive the teeth in a cavity and incrementally reposition individual teeth in a series of successive steps. This is accomplished by applying force to specific surfaces of the teeth to cause directed movement. In order to apply such force, one or more of the teeth will provide a base or anchor region for holding the positioning appliance in place while the stiffness of the polymeric material will impart a resilient repositioning force against one or more of the remaining teeth.
- stiffness creates limitations in ease of use, patient compliance, and overall cost in material, manufacturing labor and treatment time.
- the present invention utilizes polymeric or other material appliances with portions differing in rigidity, hardness, or stiffness. Portions of the appliance designed to apply specific forces may have different elastic moduluses (stiffnesses) and/or hardnesses than other portions. Alternatively, elastic moduluses and/or hardnesses may vary from one appliance to the next in a successive series to accomplish various treatment goals.
- the systems and methods of the present invention provide the design, production and use of such multiple stiffness positioning appliances in orthodontic treatment.
- the devices of the present invention provide variable stiffness appliances which may be used independently for purposes other than repositioning, such as for retaining teeth in a desired position.
- reference hereinafter to repositioning appliances with portions having differing or varying stiffnesses or hardnesses is not intended to limit the scope of the present invention and is understood to include appliances of the described design for other purposes.
- an elastic repositioning appliance may be comprised of portions with differing elastic moduluses.
- Elastic modulus may be used to express or describe the stiffness of a material or a material's resistance to elastic deformation. Therefore, elastic modulus may be used hereinafter to refer to stiffness.
- the different portions of the appliances will also usually vary in hardness. More usually, stiffer portions will be harder while the less stiff portions will be softer. Hardness is usually measured as a "durometer" reading on either the A or the D scale. In most instances, the present invention will be more concerned with the elastic modulus of the material since that will effect the force applied to the teeth for either moving the teeth or for gripping or anchoring the teeth.
- the hardness of the material may be more important, e.g., to avoid trauma to soft tissue regions engaged by the appliance.
- the remaining description and claims generally refer to materials having greater and lesser stiffnesses. It will be appreciated that such terminology will also comprise materials having greater and lesser hardnesses.
- the elastic modulus of a material is the ratio of the increment of unit stress to an increment of unit deformation within the elastic limit.
- the magnitude of the elastic modulus is indicative of the atomic and molecular bonding forces.
- the stress is relieved, the material returns to its original shape and the deformation is nonpermanent.
- Different materials may have different elastic moduluses based on their molecular structures. Some materials, such as certain polymers, may be specially produced to have different elastic moduluses while retaining similar chemical compositions (and thus assuring compatibility of the different modulus materials in a single structure). Likewise, the elastic modulus of a polymer or other material may be enhanced or otherwise modified.
- the elastic modulus may be altered by post-production methods, such as layering, coating, interpenetrating, treating with various chemical agents, and altering the temperature, to name a few.
- the elastic moduluses of the varying portions will usually range from 0.5 to 5 GigaPascal (GPa), although in some instances portions of the appliance may fall outside of this range.
- the elastic modulus of one portion may differ from another portion by 25% to 600%, or more.
- the differing elastic moduluses of different portions of the dental appliance shells of the present invention will exist while the device is present over teeth in a normal oral environment.
- different portions of the appliance shell will impart different forces to the immediately underlying teeth, where the level of the force depends both on the device geometry or tooth positions (relative to the underlying tooth or teeth, which may vary over time) and on the elastic modulus of that portion of the device (which will remain constant over time in the normal oral environment).
- the present invention should be distinguished from that described in copending application no. 09/250,962, where the stiffness of a dental appliance shell may change over time by expose to a non-oral environment, such as elevated temperature or changed osmolality.
- the dental appliance shells of the present invention which have different portions with differing stiffness may also incorporate regions (including the entire appliance) where a change in stiffness may be induced according to the teachings of application no. 09/250,962, the full disclosure of which is incorporated herein by reference.
- portions of the shell of an elastic repositioning appliance may be composed of material(s) which differ in elastic moduluses and/or hardnesses along a mesial-distal axis.
- a mesial-distal axis may be defined as an axis following the gingival line or dental arch.
- the elastic repositioning appliance may be comprised of portions with a lower elastic modulus covering the molars, for example, and portions with a higher elastic modulus covering the remainder of the teeth.
- the portions may be relatively large so that a portion may receive one or more teeth, such as contiguous molars.
- the portion of the appliance covering the anchor teeth may be of a relatively flexible nature with a lower elastic modulus than the portion covering the teeth to be repositioned. This is because the portions covering the anchor teeth may not need to apply repositioning forces to the teeth they cover; they may merely be designed to hold the appliance in place. Consequently, a high level of rigidity or stiffness may not be required. However, it may be appreciated that portions covering anchor teeth may in fact require a higher stiffness material than other portions, including portions which are designed to apply repositioning forces. Thus, any variation of stiffness or elastic modulus along a mesial-distal axis is included in this embodiment.
- portions or regions with more flexibility provides utility in ease of use for the patient.
- the patient may find ease in positioning the appliance with the more flexible portions first which may guide the appliance in placement of the more rigid, slightly misfit portions designed for repositioning. This sequence may be reversed in removal of the appliance.
- such flexibility may also allow for any slight differences in mold versus appliance versus dentition geometry which may otherwise make placement and removal of the appliance more difficult.
- a generally misfit appliance may "pop off or have a tendency to disengage even when properly positioned over the teeth. Increased flexibility may reduce these tendencies.
- portions of the elastic repositioning appliance may vary in elastic moduluses along different and/or additional axes.
- moduluses may vary along a facial-lingual axis. Facial may be defined as next to or toward the lips or cheek, including terms labial and buccal. Lingual may be defined as next to or toward the tongue. Thus, a facial-lingual axis may be described as an axis following a radial or similar line from the tongue toward the lips or cheek and vice versa. Likewise, moduluses may vary along a gingival-crown axis. This may be described as a substantially vertical axis following a line from the top of the crown at the edge of the occlusal surface of a tooth toward the gingival line or root and vice versa.
- an appliance may have a portion with a lower elastic modulus covering the occlusal surfaces of the teeth and a portion with a higher elastic modulus covering the remaining surfaces of the teeth.
- the moduluses may vary along a facial-lingual axis and/or a gingival-crown axis, depending on the boundaries of the delineated portions. Such a design may incorporate added flexibility to the appliance while maintaining adequate repositioning forces in the most efficient areas.
- the appliances of the present invention may vary in stiffness or hardness over the "thickness" of the appliance. Usually, such variations and stiffness over the thickness will be accomplished by layering the device, i.e., with layers of differing stiffnesses or hardnesses being placed successively over the mold used to form the appliances, as described in more detail below.
- the appliances may comprise shells having first and second portions, as generally described above, where each of those portions comprise layers in a laminar structure. Usually, at least one of the first and second portions will comprise a continuous layer along the mesial-distal axis.
- the second and optionally additional layers may also be continuous along the mesial-distal axis, but will often be discontinuous, i.e., broken into two or more segments.
- Such layered devices can provide a variety of benefits. For example, layers formed from stiffer or harder materials can be used to more firmly engage teeth, while the less stiff or softer layers can be used to provide compliance and greater elasticity.
- the appliance comprises a discontinuous inner layer and a continuous outer layer. At least a portion of the inner layer is configured to engage individual teeth or groups of teeth and will be stiffer or harder than the outer layer.
- the outer layer which is less stiff and therefore more compliant, provides the elasticity to move the teeth relative to one another, while the harder inner layer firmly engages the teeth to provide a better grip or anchor upon the teeth.
- the elastic modulus of the appliance shells may vary over any number of delineated portions. Such portions may be of any size, shape, thickness, or dimension. Thus, such portions may receive entire teeth or they may be of the size to cover only a portion of a tooth or dental surface.
- an appliance may be divided into, for example, two to five portions. Portions adjacent to one another differ in elastic moduluses, however not all portions of an appliance may differ from each other, such as in the case of an appliance with portions alternating between two moduluses. When portions are relatively small, an appliance may contain an unlimited number of portions, varying along any axis or combination of axes.
- such appliances comprised of portions having differing stiffness may be used independently or in a series with similar or differing devices.
- the appliance may be worn to achieve a specific goal with a single device.
- the appliance may be used as a "retainer" to hold the teeth in a desired position.
- the appliance may be used for a specific onetime repositioning movement, such as "finishing" or correcting a slight misalignment.
- the appliances may comprise a system for repositioning teeth from an initial tooth arrangement to a final tooth arrangement.
- a plurality of incremental elastic position adjustment appliances comprising polymeric or other material shells are successively worn by a patient to move teeth from one arrangement to a successive arrangement.
- Individual appliances may be configured so that their tooth- receiving cavity has a shape or geometry corresponding to an intermediate or end tooth arrangement intended for that appliance.
- successive individual appliances may have a shape or geometry differing from that of the immediately prior appliance.
- some or all of the individual appliances may also be comprised of a material stiffness differing from the stiffness of the immediately prior appliance.
- each individual appliance be comprised of portions with varying stiffnesses.
- individual appliances in the system may not vary in stiffness from prior or successive appliances, but only in geometry.
- appliances may vary only in stiffiiess (and not in geometry) when compared to immediately prior or subsequent appliances.
- systems according to the present invention may be comprised of appliances having stiffness varying within the appliance and/or from one appliance to the next in the series.
- a system of elastic repositioning appliances may comprise individual appliances having uniform elastic moduluses over their entire tooth contact area where the moduluses will differ among successive appliances used in a course of treatment.
- the elastic modulus of a given appliance may be chosen to be most suitable for a specific type of tooth movement, such as translating, tipping, root uprighting, rotation, extrusion, intrusion or a combination of these.
- translation may require 70-120 gm of force
- rotation may only require 35-60 gm of force. Therefore, an elastic positioning appliance designed for translating teeth may need to have a higher elastic modulus than one designed for purely rotating teeth. This is again due to the fact that stiffness of the appliance is a critical factor in imparting repositioning force.
- a series of appliances may be produced for a treatment plan in which successive appliances designed for a specific tooth movement may all have substantially similar elastic moduluses.
- further appliances designed for the new tooth movement may have substantially similar elastic moduluses to each other but different from the previous appliances.
- Such a sequence may be repeated at any time or may continue with new moduluses and tooth movements.
- one or more appliances may be produced with a suitably flexible elastic modulus to receive and resiliently reposition teeth from an unprescribed arrangement to a prescribed arrangement. This might be necessary in cases of lowered patient compliance.
- a patient were to remove an appliance for an unintended and/or extended period of a prescribed treatment time, the patient's teeth may move slightly out of the planned tooth progression.
- an appliance which is too rigid may not be able to accommodate these slight differences.
- a more flexible appliance (but having an identical geometry) may be produced for this purpose and may be incorporated into the treatment plan at any given point in the series of successive appliances.
- the ability to return to the same geometry is an advantage because it minimizes the need to replan the treatment protocol.
- systems for repositioning teeth from an initial tooth arrangement to a successive tooth arrangement comprise a plurality of incremental elastic position adjustment appliances in which at least one appliance has the same shape yet different elastic modulus as an immediately prior appliance.
- a series of incremental appliances may be produced with differing elastic moduluses to reposition teeth from an initial tooth arrangement to the next successive tooth arrangement in a progression of arrangements to the final arrangement.
- Each of the appliances in the series from the first to the next successive tooth arrangement may have the same shape or geometry since the tooth movement represents one step in tooth movement.
- the variance in elastic moduluses may allow for a larger step or increment in tooth movement than may be obtainable with consistent, rigid appliances.
- an appliance may be produced with a tooth arrangement which is substantially misaligned from the initial arrangement.
- High modulus appliances may not be flexible enough to allow the appliance to fit over the teeth in the initial arrangement.
- a series of appliances of the same shape may be produced with increasing elastic moduluses from relatively low to adequately high.
- the patient may begin with the lowest elastic modulus appliance which may be the most flexible to fit over the teeth.
- the patient may successively utilize each appliance in increasing modulus until the teeth have conformed to the successive tooth arrangement.
- the patient may begin a new series of appliances with varying moduluses and a shape to reposition the teeth to the arrangement of the next step in the repositioning progression.
- the elastic modulus of an appliance or portions of an appliance may be modified in a number of different ways.
- the elastic modulus may be determined by the choice of materials.
- metals will generally have a higher elastic modulus than polymers due to atomic structure.
- the modulus values for metals may range between 48 and 414 GPa
- the modulus for polymers may range from 0.5 to 35 GPa.
- the appliances will comprise or consist of a polymeric shell formed from a single polymer, multiple polymers, copolymers, and the like, typically by thermo forming and/or lamination.
- Stiffness of a polymer may be varied within a range (typically 0.5 GPa to 5 GPa) by changing the molecular structure of the polymer chains. Polymer chains with hindered side-chains are unable to pack as closely as those with smaller side-chains. Thus, such a polymer may have more intermolecular motion and therefore a lower bulk elastic modulus. Stiffness can also be changed by controlling the degree of cross-linking as well as the cross-linking entity within a polymer or copolymer.
- differing elastic moduluses may be created within the same polymer shell by layering or laminating the same or different polymers. Two layers of a polymer material bonded together to form an integral appliance, i.e., an appliance having a monolithic shell structure where the layers are resistant to delamination, may have a higher elastic modulus than a single layer of such material. Thirdly, different elastic moduluses may be created with a single layer of one type of polymer material by production methods, such as coating, treating with various chemical agents, and altering the temperature, to name a few.
- a polymer material may be reinforced with structures such as strips, wires, pieces, mesh, lattices, networks, and the like. These structures may be comprised of any suitable material, particularly metals and alloys but also including polymer filaments, wires, braids, and the like.
- composite materials may be comprised of interpenetrating polymeric networks.
- An interpenetrating polymeric network is comprised of a base material and an additional material that interpenetrates the base material to alter its mechanical properties.
- the base material (A) may be a solid polycarbonate.
- the added material (B) may be a liquid polymer, monomer or crosslinking agent which is allowed to interpenetrate and activate to form a composite network.
- the composite (A+B) may have a stiffness which is greater than the sum of its parts, (A) and (B).
- another material (C) may also be allowed to interpenetrate and activate to form a new composite network.
- the composite (A + B + C) may also have a stiffness which is greater than the sum of its parts, (A), (B) and (C).
- Fig. 1 is a perspective illustration of an embodiment of an appliance of the present invention and descriptive axes.
- Fig. 2 illustrates an embodiment of an appliance with relatively large portions varying in elastic modulus along a mesial-distal axis.
- Fig. 3 illustrates an embodiment of an appliance with smaller portions varying in elastic modulus in a non-symmetric pattern along a mesial-distal axis.
- Fig. 4 illustrates an embodiment of an appliance varying in elastic modulus along a mesial-distal axis in which portions covering proximal or interproximal spaces are of differing modulus.
- Fig. 5 illustrates a variety of appliance portions varying in elastic modulus along a mesial-distal axis.
- Fig. 6 is a perspective illustration of an embodiment of an appliance varying in elastic modulus along a facial-lingual axis.
- Fig. 7 illustrates a variety of appliance portions varying in elastic modulus along a facial-lingual axis.
- Fig. 8 is a perspective illustration of an embodiment of an appliance varying in elastic modulus along a gingival-crown axis.
- Fig. 9 illustrates a variety of appliance portions varying in elastic modulus along a gingival-crown axis.
- Fig. 10 illustrates a variety of appliance portions varying in elastic modulus along one or more described axes.
- Fig. 11 depicts a series of appliances differing in elastic modulus at specific intervals throughout a treatment plan.
- Fig. 12 illustrates the use of an "off track" appliance in a prescribed treatment plan.
- Fig. 13 illustrates the use of a series of appliances with gradually increasing elastic moduluses and similar or identical geometry in a series of intervals throughout a treatment plan.
- Fig. 14 illustrates a method of fabricating a multi-modulus appliance.
- Fig. 15 illustrates a method of layering to fabricate a multi -modulus appliance.
- Fig. 16 illustrates an additional method of layering to fabricate a multi- modulus appliance.
- Fig. 17 illustrates an exemplary layered appliance according to the present invention with portions broken away.
- Fig. 18 is a cross-sectional view taken along line 18-18 of Fig. 17.
- the present invention provides improved devices, systems and methods for incrementally repositioning teeth using a plurality of discrete polymeric appliances of variable flexibility, where each appliance successively repositions one or more of the patient's teeth by relatively small amounts. Flexibility may be defined by elastic modulus of the polymeric material and may vary within a given appliance or may vary throughout a series of appliances according to a prescribed orthodontic treatment plan.
- portions of an elastic repositioning appliance 100 may vary in elastic modulus along a mesial-distal axis 101, facial-lingual axis 102, gingival- crown axis 103, or any axis in-between these representative axes.
- a mesial-distal axis may be described as an axis following the gingival line or dental arch
- a facial-lingual axis may be described as an axis following a radial or similar line from the tongue area toward the lip or cheek area
- a gingival-crown axis may be described as an axis following a substantially vertical line from the crown of a tooth toward the gingival line or root.
- portions of an elastic repositioning appliance 100 may vary in elastic modulus mesial-distally.
- portions with a lower elastic modulus 110 are shaded to easily distinguish differences in elastic modulus throughout a device.
- the appliance 100 may be described as having three portions. Two portions cover contiguous sets of molars and are comprised of an elastomeric material of a lower elastic modulus 110 and are thus shaded. The portion in- between these portions is of a higher elastic modulus 111 and is thus not shaded.
- All portions in this embodiment are relatively large so that the portions may receive one or more teeth, such as molars, premolars, incisors, and the like.
- nonadjacent portions may have the same elastic modulus, such as the two lower elastic modulus 110 portions, or they may be different from each other while maintaining a difference from the higher elastic modulus 111 portion.
- an appliance 100 with three distinct portions may be comprised of two or three elastic moduluses. As illustrated in Fig. 3, such portions may not be symmetrical and they may not cover more than one tooth.
- Portions with a lower elastic modulus 110 may alternate in an uneven fashion along a mesial-distal axis as shown.
- adjacent portions may be of a size to cover only a portion of a tooth or dental surface.
- portions of lower elastic modulus 110 may be present covering the facial or lingual surfaces of the teeth, while portions of higher elastic modulus 111 may be present covering the proximal or interproximal spaces.
- This may be advantageous to provide repositioning forces, such as translation forces, at the most efficient locations for this type of movement.
- flexibility is provided in portions that may be less involved in the application of force, allowing more freedom and comfort for the patient.
- the elastic modulus of an appliance 100 may vary over any number of delineated portions and may be of any size, shape, thickness or dimension, to name a few.
- Such portions may be sized to receive an entire tooth 115 or they may be of the size to cover only a portion of a tooth.
- a portion with a lower elastic modulus 110 may be sized to cover a proximal or interproximal space 116, including portions covering the gingival line. This may be desirable to provide comfort to the gums when wearing the appliance, and also to increase the contact of the appliance with the interproximal regions. In this case, softer, more flexible material may be able to form more closely to the interproximal regions, enabling a higher level of repositioning force to be applied.
- Portions may also be sized and arranged to cover part of a facial surface 117, or two or more of such portions may cover part of a facial surface 118, allowing the elastic modulus to vary mesial-distally within a single tooth. Further, the portion may be sized to cover an isolated region of a facial surface 119.
- Such embodiments are a limited presentation of the possible sizes, configurations, and combinations of varying elastic modulus portions in an appliance 100 of the present invention. Such possibilities may be unlimited.
- portions of an elastic repositioning appliance 100 may vary in elastic modulus facial- lingually.
- the appliance 100 is shown to have a portion with a lower elastic modulus 110 covering a portion of the occlusal surfaces of the teeth and a portion with a higher elastic modulus 111 covering the remaining surfaces of the teeth.
- the elastic modulus varies along a facial-lingual axis.
- Such a design may be beneficial to provide repositioning forces, such as translation forces, along the proximal and/or interproximal spaces which are the most efficient locations for this type of movement.
- flexibility is provided in portions that may be less involved in the application of force, the occlusal surfaces.
- the elastic modulus of an appliance 100 may again vary over any number of delineated portions and may be of any size, shape, thickness or dimension, to name a few.
- a portion of lower elastic modulus 110 may be sized to cover only a portion of a tooth. For example, it may cover the center of the occlusal surface 125, alternating cusps or cusp tips 126, or isolated portions of any given cusp or cusp tip 127.
- a portion of lower elastic modulus 110 may be of a larger size to cover, for example, the outside margin or buccal cusps of a tooth 128 or the inside margin or lingual cusps of a contiguous grouping of teeth 129.
- such embodiments are a limited presentation of the possible sizes, configurations, and combinations of varying elastic modulus portions in an appliance 100 of the present invention. Such possibilities may be unlimited.
- portions of an elastic repositioning appliance 100 may vary in elastic modulus crown-gingivally.
- the appliance 100 is shown to have a portion with a lower elastic modulus 110 covering the occlusal surfaces of the teeth and a portion with a higher elastic modulus 111 covering the remaining surfaces of the teeth.
- the portion of lower elastic modulus 110 partially covered a portion of the occlusal surfaces.
- the occlusal surface is substantially covered with the lower elastic modulus 110 material, therefore it may be considered to be uniform, non-variable, along a facial-lingual axis. It may be more properly described as varying along a gingival-crown axis, as the lower elastic modulus 110 portion may extend over the cusps of the tooth crowns.
- the lower elastic modulus 110 material may be seen as being located at the tip of the crown region and vary to a higher elastic modulus 111 material toward the gingival line or margin.
- a higher elastic modulus 111 material along the gingival line or margin may improve retention of the device on the teeth.
- a polymeric shell may have a plurality of windows over portions of the occlusal surfaces of the teeth. In this case, segments of the shell may still be present along the facial and lingual surfaces of the teeth and across the interdental regions or spaces between the teeth. Exposure of the occlusal surfaces in appropriate size and location may allow interdigitation of the upper and lower teeth.
- the elastic modulus of an appliance 100 may again vary over any number of delineated portions and may be of any size, shape, thickness or dimension, to name a few.
- a portion of lower elastic modulus 110 may be sized to cover only a portion of a tooth along this axis. For example, it may cover the upper portion of the lingual surfaces near the cusps of the crown 135, or a midway "stripe" through the lingual surface of a tooth 136.
- it may be sized so that more than one "stripe” may cover the surface of a tooth 137, as in the case of a portion at the gingival margin and a portion near the cusps of the crown.
- a portion of lower modulus may be sized so that it covers a contiguous grouping of teeth, such as the buccal surfaces along the gingival margin 138.
- such embodiments are a limited presentation of the possible sizes, configurations, and combinations of varying elastic modulus portions in an appliance 100 of the present invention. Such possibilities may be unlimited.
- variance in elastic modulus in relation to size, shape, location, orientation, and axis, as described above, may be combined in a single appliance 100 to provide an unlimited variety of appliance 100 designs and constructions.
- portions of the appliance 100 vary mesial-distally, such as by comparing the lower elastic modulus 110 portion covering a group of incisors with the higher elastic modulus 111 portion covering the canine tooth. Portions may also vary facial-lingually, as depicted by the partial covering of the occlusal surfaces of the molars 150 or the isolated portion of a given cusp or cusp tip 127. Likewise, portions may vary crown- gingivally, such as the portions covering the buccal surfaces along the gingival margin 138.
- portions adjacent to these areas are not identical, as in comparison of portions covering the buccal surfaces along the gingival margin 138 with the adjacent tooth 151 having partial covering of the occlusal surface of the molar 150.
- Portions may also vary along the three major axes simultaneously. This can be seen in the portion covering the center of an occlusal surface 125, which varies facial-lingually, the lingual face of a molar along the gingival margin 152; which varies crown-gingivally, and the adjacent uniformly covered molar 153, which varies mesial-distally in relation to the previous portions.
- systems for repositioning teeth from an initial tooth arrangement to a final tooth arrangement may be comprised of a plurality of incremental elastic position adjustment appliances with varying elastic moduluses.
- a plurality of such appliances 100 with differing patterns of elastic modulus variance may be used in a system for repositioning teeth throughout a sequence of tooth arrangements. This may be illustrated by Figs. 2-10 with differing tooth geometries, viewed as a series of appliances 100 for a single treatment plan.
- the polymeric shells of the appliances 100 may have uniform elastic moduluses over their entire tooth contact area.
- each appliance 100 differs in shape or tooth geometry and represents a stage in the overall treatment plan.
- the first three appliances 200, 201, and 202, respectively, may have a uniform elastic modulus chosen for a specific type of tooth movement.
- appliances 200, 201 and 202 may be designed for pure translation, requiring a relatively high elastic modulus 111.
- the appliances are not shaded in the illustration.
- a different type of tooth movement such as tipping, may be desired requiring a lower elastic modulus 110.
- appliances 203 and 204 may continue the series of differing shape or tooth geometries to create such movements, but the elastic modulus may differ from the prior appliances, 200, 201, and 202. Thus, these appliances are shaded in the illustration.
- the remainder of the treatment plan may feature a similar series of appliances, including appliances with uniform elastic moduluses which differ from the appliances immediately prior and/or any appliances previously presented in the series. Likewise, such a series may also include appliances with combined variances, as described above.
- a treatment plan may be prescribed with a series of appliances 100 differing in shape or tooth geometry, of which four stages are depicted, 210, 211, 212 and 213.
- Such appliances may have any given elastic modulus that is suitable for the prescribed function.
- such appliances may have internal variance in elastic modulus, described previously, or may vary wholly from appliance to appliance throughout the prescribed treatment plan.
- the patient's teeth may move slightly out of the planned tooth arrangement.
- Such a patient may be considered "off track" in which their current tooth arrangement has diverted from the series of projected tooth arrangements, creating an unprescribed tooth arrangement.
- a new more flexible appliance 214 may be produced for this purpose and may be incorporated into the treatment plan.
- Such an appliance 214 may have the same shape or tooth geometry as the next successive appliance 212, but it may have a lower elastic modulus 110, depicted by shading. The increased flexibility may allow the appliance 214 to conform to the unprescribed arrangement and reposition the teeth toward an arrangement that the next successive appliance 212 may therefore fit.
- Such an appliance 214 may be used at any point in the series of successive appliances.
- a series of incremental appliances, 300, 301, 302, 303, 304 and 305 may be produced with differing elastic moduluses, illustrated by variation in shading, to reposition teeth from an initial tooth arrangement to the next successive tooth arrangement in a progression of arrangements to the final arrangement.
- Fig. 13 illustrates two steps in such a progression.
- a step or stage represents a change in shape or geometry of an appliance 100 to reposition the teeth into the next prescribed arrangement in a series. Therefore, appliances 300, 301, and 302 represent the first stage and have one shape and 303, 304, and 305 represent the second stage and have a differing shape.
- the appliances 300, 301, and 302 representing the first stage may vary in elastic moduluses from more flexible (appliance 300) to more rigid (appliance 302).
- the patient may begin the treatment sequence with the more flexible appliance 300 of the first stage.
- Such flexibility may allow an appliance with a substantially misaligned geometry to fit over the patient's teeth and apply repositioning forces.
- the patient may progress to the next appliance 301 in the first stage.
- This appliance 301 may be more rigid than the prior appliance 300.
- the patient may continue through any number of appliances throughout a stage. Upon completion of the stage, the patient may repeat the process in stage two, beginning with the more flexible appliance 303 and culminating with the more rigid appliance 305. The patient may then continue through any number of stages to the endpoint of treatment.
- the variance in elastic modulus throughout each step may allow for a larger step or increment in tooth movement between each step than may be obtainable with consistent, rigid appliances.
- Such flexibility may allow the appliance to fit over a tooth arrangement that is more misaligned while the increase in rigidity throughout each stage may provide sufficient repositioning forces which may not be obtainable with highly flexible appliances.
- These larger steps require fewer appliances in a series to have a change in shape or geometry. Consequently, fewer molds may be required to form such appliances, which lowers cost and treatment time for the patient.
- the appliance may be flexible enough to fit over the teeth in the unprescribed arrangement and gradually reposition the teeth throughout the stage as originally prescribed. This may also reduce cost and treatment time since the production and fitting of a flexible "off track" appliance, as illustrated in Fig. 12, may be avoided.
- the elastic modulus of an appliance or portions of an appliance of the present invention may be determined by a number of design features, methods, materials and similar means.
- the appliance may be comprised of a polymeric shell which is heat formed over a mold of a patient's dentition.
- thermoforming This is typically accomplished by heating a thermoformable polymer material and applying vacuum or pressure to form the polymer to the mold.
- reaction casting may be used to produce such an appliance.
- description will pertain to thermoforming, however such concepts and techniques may be equally applied to reaction casting or similar methods and are not to limit the scope of the invention.
- a polymer sheet with a specific elastic modulus and thickness may be thermoformed over a mold and trimmed for patient use.
- Appliances with differing uniform elastic moduluses may be produced by altering one or more of three variables: 1) polymer type, 2) elastic modulus, 3) thickness.
- portions of polymer sheeting 400 may be positioned over a mold 401 in designated areas and thermoformed together into a final polymeric appliance. Each portion of sheeting 400 may be chosen based on the three above mentioned variables to provide a desired elastic modulus. Each portion of sheeting 400 may then be positioned in the desired location for elastic modulus changes throughout the finished appliance.
- a first sheet 402 placed over the right side molars a second sheet 403 placed over the left side molars and a third sheet 404 placed over the remainder of the teeth.
- Sheets 402 and 403 are depicted as having differing elastic moduluses to each other and to sheet 404, as shown by shading gradations, however such sheets 402, 403, may be identical.
- a finished appliance may appear as that illustrated in Fig. 2.
- portions with differing elastic moduluses may be created with the same polymer or different polymers material by layering. Two layers of a polymer material bonded together may have a higher or elastic modulus than a single layer of such material. As illustrated in Fig.
- a first sheet 405 may be placed over the incisors, canines and premolars of the mold 401 and a second sheet 406 may be placed over the entire dentition.
- Each sheet may be the same or may differ in terms of any or all of the above mentioned variables.
- a finished appliance may also appear as that illustrated in Fig. 2.
- the shell covering the molars is comprised of one layer and the remainder of the appliance is comprised of two layers formed into an integral appliance structure. Therefore, the portions covering the molars may have a lower elastic modulus, depending on the combination of materials, than the remaining portion.
- a multi-layered structure may have a lower elastic modulus than a single layered structure depending on the above mentioned variables.
- the described layering technique may provide a variety of moduluses and those stated examples are not intended to limit the scope of the invention.
- portions with different elastic moduluses may be created by a multi-step process of layering.
- a first sheet may be thermoformed over the entire dentition of a mold 401 to form a base appliance 410.
- Portions desired to be of a differing elastic modulus 411, demarcated by a dashed line, may be cut and removed from the formed base appliance 410.
- a second sheet 412 may then be thermoformed over the entire dentition. This may result in a single layer of material in the portion of differing elastic modulus 411 and a double layer of material in the remaining areas.
- appliances with differing and gradually changing elastic moduluses may be created by any number of production methods.
- a base appliance 410 may be coated in a specific area with one or more polymer solutions to "build up" a portion of the appliance for localized rigidity. Such a build-up may also be gradual for a more gradual increase in rigidity.
- a base appliance 410 may be treated in specific areas with various chemical agents to either increase or reduce localized rigidity. This may also include treatments involving temperature changes and other phase altering methods. Similarly, such methods may be combined, including any or all of the above described methods. Likewise, such methods may be utilized for appliances of uniform elastic modulus.
- the fabrication process illustrated in Fig. 16 may be used to prepare a preferred laminated appliance structure 500, as illustrated in Figs. 17 and 18.
- An inner layer 502 is formed from a relatively stiff polymeric material and molded over a positive tooth model which represents the desired appliance geometry. After the layer 502 is formed, it can be segmented into two or more sections which conform to individual teeth or groups of teeth when the appliance is placed over the patient's jaw. As shown in Fig. 17, gaps 504 may be formed between individual sections 506, each of which conform to and receive an individual tooth or group of teeth.
- An outer layer 508 is continuous in the mesial-distal axis and covers all the segments 506 of the inner layer 502.
- the stiffness or anchoring force can be enhanced without having to concurrently modify the overall or effective elasticity of the appliance which can be selected based on the clinical requirements of moving teeth. That is, the elasticity of the outer layer can be selected to provide an appropriate tooth movement force while that of the inner layer can be chosen to enhance seating characteristics over the teeth.
- the compliance of the outer layer 508 could be varied along the mesial-distal axis in order to provide for differing forces on the teeth, as discussed generally above.
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP01928821.6A EP1274363B1 (en) | 2000-04-25 | 2001-04-24 | System for repositioning teeth with appliances having varying stiffness |
JP2001577867A JP2004507281A (en) | 2000-04-25 | 2001-04-24 | System and method for modifying a modulus instrument |
AU2001255637A AU2001255637A1 (en) | 2000-04-25 | 2001-04-24 | Systems and methods for varying elastic modulus appliances |
ES01928821.6T ES2594884T3 (en) | 2000-04-25 | 2001-04-24 | Systems for repositioning teeth with devices that have variable stiffness |
EP10181286.5A EP2266493B1 (en) | 2000-04-25 | 2001-04-24 | Systems for varying elastic modulus of orthodontic appliances |
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US60/199,650 | 2000-04-25 | ||
US60/199,649 | 2000-04-25 | ||
US09/616,830 | 2000-07-14 | ||
US09/616,222 | 2000-07-14 | ||
US09/616,830 US6524101B1 (en) | 2000-04-25 | 2000-07-14 | System and methods for varying elastic modulus appliances |
Publications (1)
Publication Number | Publication Date |
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WO2001080764A1 true WO2001080764A1 (en) | 2001-11-01 |
Family
ID=24471105
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2001/013217 WO2001080764A1 (en) | 2000-04-25 | 2001-04-24 | Systems and methods for varying elastic modulus appliances |
Country Status (1)
Country | Link |
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WO (1) | WO2001080764A1 (en) |
Cited By (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1323393A1 (en) * | 2000-10-03 | 2003-07-02 | Gakuji Ito | Mouthpiece for orthodontic treatment and device for orthodontic treatment using the mouthpiece |
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WO2007128270A2 (en) * | 2006-05-10 | 2007-11-15 | Smh Biomaterial Ag | Method for the production of a dental brace comprising soft and hard brace zones |
US8449296B2 (en) | 2005-03-25 | 2013-05-28 | Den Mat Holdings, LLC | Dental appliance |
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Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4370129A (en) * | 1981-06-18 | 1983-01-25 | Professional Positioners, Inc. | Tooth positioner with harder areas |
US4799884A (en) | 1987-11-04 | 1989-01-24 | Bergersen Earl Olaf | Expansion/buccal shield appliance |
US4983334A (en) | 1986-08-28 | 1991-01-08 | Loren S. Adell | Method of making an orthodontic appliance |
US5536168A (en) * | 1990-06-25 | 1996-07-16 | Bourke; Kevin J. | Mouth worn apparatus, a method for treating jaw and teeth malformations, and a method for preventing snoring |
US6183248B1 (en) | 1998-11-30 | 2001-02-06 | Muhammad Chishti | System and method for releasing tooth positioning appliances |
US6309215B1 (en) | 1997-06-20 | 2001-10-30 | Align Technology Inc. | Attachment devices and method for a dental applicance |
-
2001
- 2001-04-24 WO PCT/US2001/013217 patent/WO2001080764A1/en active Search and Examination
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4370129A (en) * | 1981-06-18 | 1983-01-25 | Professional Positioners, Inc. | Tooth positioner with harder areas |
US4983334A (en) | 1986-08-28 | 1991-01-08 | Loren S. Adell | Method of making an orthodontic appliance |
US4799884A (en) | 1987-11-04 | 1989-01-24 | Bergersen Earl Olaf | Expansion/buccal shield appliance |
US5536168A (en) * | 1990-06-25 | 1996-07-16 | Bourke; Kevin J. | Mouth worn apparatus, a method for treating jaw and teeth malformations, and a method for preventing snoring |
US6309215B1 (en) | 1997-06-20 | 2001-10-30 | Align Technology Inc. | Attachment devices and method for a dental applicance |
US6183248B1 (en) | 1998-11-30 | 2001-02-06 | Muhammad Chishti | System and method for releasing tooth positioning appliances |
Non-Patent Citations (1)
Title |
---|
See also references of EP1274363A4 * |
Cited By (40)
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US7810503B2 (en) | 2004-04-06 | 2010-10-12 | Georges Magnin | Mandibular advancement splint |
EP1602347A1 (en) * | 2004-06-04 | 2005-12-07 | Georges Magnin | Mandibular advancer orthesis. |
WO2005117776A2 (en) * | 2004-06-04 | 2005-12-15 | Georges Magnin | Mandibular advancement orthesis |
WO2005117776A3 (en) * | 2004-06-04 | 2006-07-06 | Georges Magnin | Mandibular advancement orthesis |
US9901429B2 (en) | 2005-03-25 | 2018-02-27 | Den-Mat Holdings, Llc | Dental appliance |
US8449296B2 (en) | 2005-03-25 | 2013-05-28 | Den Mat Holdings, LLC | Dental appliance |
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WO2007128270A3 (en) * | 2006-05-10 | 2008-10-09 | Smh Biomaterial Ag | Method for the production of a dental brace comprising soft and hard brace zones |
DE102006021955A1 (en) * | 2006-05-10 | 2007-11-15 | Konrad Hofmann | Method for producing a toothed rail with soft and hard rail areas |
US11610274B2 (en) | 2007-03-02 | 2023-03-21 | Align Technology, Inc. | Methods for volume manufacturing of items |
US11077557B2 (en) | 2010-05-14 | 2021-08-03 | Cognex Corporation | System and method for robust calibration between a machine vision system and a robot |
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US11813135B2 (en) | 2014-01-31 | 2023-11-14 | Align Technology, Inc. | Methods for direct fabrication of orthodontic appliances with elastics |
US11648089B2 (en) | 2014-01-31 | 2023-05-16 | Align Technology, Inc. | Orthodontic appliances and systems with elastic members |
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