Method and apparatus for slow palate expansion

Provided are orthodontic devices to orthopedically expand the upper jaw including a pre-formed arch wire adapted to conform to the interior contours of a patient's mouth. The arch includes a rear portion positioned at a level about a patient's rear molars and includes a first end and a second end adapted to slidably engage associated buccal tubes. The arch also includes a front portion positioned at a level above a patient's gingiva and into the patient's vestibule, and a rise portion between the rear portion and front portion that changes the effective level of the arch wire from the rear portion to the front portion. The device also includes a means for attaching the wire to the molar teeth.

TECHNICAL FIELD

The present invention relates to orthodontic devices. More particularly, the present invention is directed at an improved device for orthopedically expanding the upper jaw to gain a better relationship with the lower jaw and to make space for irregular teeth.

BACKGROUND

Orthodontic devices are used to treat irregularities in teeth and jaws. For patients with minor irregularities braces are sufficient to correct these issues. Often however, the use of braces as a lone treatment is not sufficient. In the common case of crowding, a palatal expander is needed to widen the upper and lower jaws to improve the fit between the upper and lower teeth, and to make space for any irregularly crowded teeth.

Palate expansion can be classified into two categories of expansion: slow and rapid expansion. Slow expansion expands the palate at a rate of 0.5 to 1 mm per week as is associated with greater stability and permanency.

A commonly used device for slow palatal expansion is the Kloehn face bow. The face bow and variations are shown in U.S. Pat. Nos. 721,655, 3,036,380, 3,111,758, 3,137,841, 3,311,978, 3,314,151, and 3,429,044. In general, the Kloehn face bow includes an inner bow which attaches inside a patient's mouth to a patient's molar teeth and an outer bow outside of the mouth that is attached to an external strap to be worn around a patient's head or neck.

When expanding, the inner arch wire of the Klohen tips the crowns buccally. The outer bow and pull of the neck straps tip the crowns lingually. Ultimately, one effect cancels the other, resulting in a bodily lateral expansion force. The large, well anchored, tripod roots of the first molars offer more than enough anchorage to cause the mid-palatal suture to grow. This well-established method results in a molar anchorage that is 75-80% efficient. For improved expansion results, it is desirable to increase the molar anchorage efficiently.

U.S. Pat. No. 4,212,637 sought to improve the safety of the device by creating a Kloehn like device with an outer bow that was separable from the inner bow. However, with the outer bow being capable of being removed, it is possible that a user of this device may choose to not to wear the outer bow, decreasing compliance as well as the efficiency of the device. Thus, it is desirable to have a more attractive device that increases compliance and simultaneously maintains proper anchorage efficiency, thus making it an overall more efficient device.

It is also known in the art to provide auxiliary wires 7-10 mm from each end of the arch wire to provide an additional anchoring location of the arch wire and prevent rotation and tipping of the attached molars.

SUMMARY OF THE DISCLOSURE

Disclosed herein are palatal expansion devices without an unattractive outer bow having increased molar anchorage efficiency. The devices and methods disclosed herein support a technique to orthopedically expand the maxillary bone permanently and orthodontically create space for crowded teeth.

In accordance with one aspect of the disclosure an orthodontic device includes an arch wire adapted to be positioned inside a patient's mouth. In some embodiments, the arch wire is a pre-formed wire adapted to conform to the contour of a patient's mouth. The arch wire includes a rear portion, wherein the rear portion is positioned at a level about a patient's rear molars and includes a first end and a second end; wherein the first and second ends are adapted to slidably engage associated buccal tubes. The arch wire also includes a front portion; wherein the front portion is positioned at a level above a patient's gingiva and into the patient's vestibule, and a rise portion, between the rear portion and front portion, wherein the rise portion changes the effective level of the arch wire from the rear portion, positioned about a person's molars, to the front portion, positioned above a patient's gingiva and into the patient's vestibule. The device also includes a means for attaching the wire to a pair of teeth.

In accordance with one aspect of the disclosure, the cross-section of the arch wire is selected from the group including a substantially D-shaped cross section, a substantially H-shaped cross-section, a substantially X-shaped cross-section, a substantially +-shaped cross-section, a substantially rectangular-shaped cross-section, a substantially circular-shaped cross-section, and a substantially oval-shaped cross-section.

In accordance with another aspect of the disclosure, the arch wire further includes an inner facing surface and an outer facing surface, wherein the inner facing surface is a concave surface facing a patient's gingiva and the outer facing surface is a convex surface facing a patient's buccal and labial vestibular tissue.

In accordance with another aspect of the disclosure, the front and rise portions of the arch wire include inner facing surfaces and outer facing surfaces, wherein the inner facing surfaces are substantially concave surfaces facing a patient's gingiva and the outer facing surfaces are convex surfaces facing a patient's buccal and labial vestibular tissue. The rear portions of the device have a cross-section that is the same as the front portion or is different and selected from but not limited to the group including a substantially D-shaped cross section, a substantially H-shaped cross-section, a substantially X-shaped cross-section, a substantially +-shaped cross-section, a substantially rectangular-shaped cross-section, a substantially circular-shaped cross-section, and a substantially oval-shaped cross-section.

In accordance with one aspect of the disclosure, the first end and second ends of the arch wire are beveled to aid insertion of the arch wire ends into associated attachment means/buccal tubes.

In accordance with another aspect of the disclosure, a device includes a first and second ring, wherein the first ring is attached to the arch wire between the rear portion and rise portion of the first end and the second ring is attached to the arch wire between the rear portion and rise portion of the second end, wherein when the first and second ends are slideably engaged in the associated buccal tubes, the rings provide a stop, restricting additional rearward movement, when the first and second rings contact the associated buccal tubes.

In accordance with another aspect of the disclosure, the first and second rings each have an inner facing surface and an outer facing surface, wherein the inner facing surface is a concave surface facing a patient's gingiva and the outer facing surface is a convex surface facing a patient's buccal and labial vestibular tissue, wherein the first ring is attached between the rear portion and rise portion of the first end and the second ring is attached between the rear portion and rise portion of the second end, and wherein when the first and second ends of the rear portion of the arch are slideably engaged in the associated buccal tubes the rings provide a stop when in contact with the associated buccal tubes.

In accordance with another aspect of the disclosure, an orthodontic device further includes at least one washer, wherein the washer has an aperture adapted to slidably engage the arch wire and is placed between the first or second rings and attachment means.

In accordance with another aspect of the disclosure, an orthodontic device further includes an elongated appendage adapted to be secured to the front portion of the arch, wherein the elongated appendage extends into the labial musculature of a patient.

In accordance with another aspect of the disclosure, the elongated appendage is plastic or nylon material. In some embodiments the elongated appendage is bonded or fused to the front portion of the arch wire. In other embodiments the elongated appendage snap fits to the arch wire.

In some embodiments, and in accordance with another aspect of the disclosure, the orthodontic device includes first and second auxiliary wires each having a front end and a rear end; wherein the front ends of the first and second auxiliary wires are attached to the main arch wire between the rear portion and rise portion. The rear ends of the auxiliary wires are adapted to slideably engage a second attachment means.

Also described herein are inventive methods for expanding a patient's palate. A patient's dental arch is measured, a means for anchoring an orthodontic device is attached or banded to selected rear teeth of the patient, an arch adapted to be positioned inside a patient's mouth a pre-formed wire adapted to conform to a the contour of a dental arch of a patient and having a rear portion wherein the rear portion is positioned at a level about a patient's rear molars and includes a first end and a second end; wherein the first and second ends are adapted to slidably engage associated tubes attached to said means for anchoring; a front portion, wherein the front portion is positioned at a level above a patient's gingiva and into the patient's vestibule; a rise portion between the rear portion and front portion wherein the rise portion changes the level from the rear portion positioned about a person's molars to the front portion positioned above a patient's gingiva and into the patient's vestibule.

After several weeks the patient's palate will slowly expand, if more expansion is desired the arch wire can be removed and expanded, meaning that the radius of curvature of the device is increased by bending the rear portions of the device outward. In some cases replacing the arch with a larger arch wire may be preferred.

In accordance with another aspect of the present disclosure the method includes proving an arch wire including a first and second ring, wherein the first ring is attached between the rear portion and rise portion of the first end and the second ring is attached between the rear portion and rise portion of the second end, wherein when the first and second ends are slideably engaged in the associated buccal tubes, the rings provide a stop, restricting additional rearward movement, when the first and second rings contact the associated buccal tubes. In some embodiments the method includes providing washers wherein the washer has an aperture adapted to slidably engage the arch wire and is placed between the first or second rings and attachment means of the tooth.

In accordance with another aspect of the present disclosure the method includes providing an arch wire including an elongated appendage that is attached to the front portion of the arch wire.

DETAILED DESCRIPTION

The structures shown schematically in the drawings have parts that are examples of the elements recited in the claims. The illustrated structures thus include examples of how a person of ordinary skill in the art can make and use the claimed invention. It is described here to meet the enablement and best mode requirements of the patent statute without imposing limitations that are not recited in the claims. The words used in the claims have their full or ordinary meanings.

The present application contemplates devices and methods, for utilizing an orthodontic slow palatal expansion.

FIG. 1, shows the prior art Kohlen device10. The device10includes an arch wire12that is placed inside the patient's mouth and an exterior bow14that is outside of the patient's mouth. The inner arch wire12, is placed in the mouth such that ends of the device are inserted into mounting tubes16which are anchored to rear molars18. The device also includes an exterior bow14that is connected to the inner arch wire12at point20. The exterior bow14includes ends22which are adapted to receive a strap that is worn around the patient's head. When expanding, the inner arch wire12of the Koehn10tips the crowns of the molars18buccally. However with the exterior bow14bent up, the pull of a neck strap from an inferior position, tips the crowns of molars18lingually. The effects cancel each other out, resulting in a bodily lateral expansion force. The large well anchored tripod roots of the first molars offer more than enough anchorage to cause growth at the mid-palatal suture; thus resulting in the most physiologic and permanent method of apical base expansion.

It is an object of this invention to increase the molar anchorage without the bulky and unattractive exterior bow14. With reference toFIGS. 2 and 3, the palate expander device100includes a resilient wire101that is generally U-shaped. The wire ends108A and108B are adapted extend rearward into a patient's mouth to engage and insert into a set of buccal tubes114for attachment. The device applies an outward force, pulling the teeth buccally to expand the palate. The device has a first (right) side105, a second (left) side107and three portions102,104, and106. A front portion102sits in the front of a patient's mouth and is positioned above a patient's gingiva103and partially extends into the labial musculature of a patient. A rear portion106is adapted to be positioned about the rear molars110of a patient. The rear portion contains two ends of the arch wire108A and108B which slidably engage buccal tubes114for attachment to the teeth. A rise portion104is located between the rear portion106and front portion102. The rise portion changes the effective level from the rear portion106, positioned about a patient's molars110, to the front portion102, positioned above a patient's gingiva103. The rise is a step as shown inFIG. 3Aor can be a gradual change. However, it is understood that any geometry may be used to change the level from a level about a patient's molars to a slightly higher level above a patient's gingiva103.

The arch wire101should be made of a material that is sufficiently stiff as to eliminate or reduce tooth movement. However, too much force applied could damage a person's mouth. The material should also be compatible in an oral environment, be able to withstand corrosion, and be non-toxic for patients. 18/8 stainless steel is commonly chosen in dental applications for these desirable characteristics. In accordance with one aspect of the disclosure the arch wire ranges in size from 0.040 to 0.060 inches in diameter.

With continued reference toFIG. 3A, buccal tubes114are mounted to rear molars. The buccal tubes114can be fixed to the molars themselves or to attachment bands112which are secured to the rear molars110. The buccal tubes114are adapted to receive a first end108A and a second end108B of the rear portion106of arch wire101.

In some embodiments the ends of the wires108A and108B are beveled, as shown inFIG. 3Bat109, to aid in insertion of the arch wire101into the buccal tube114.

With reference toFIG. 3B and 3C, rings120are fixed to the arch wire101between the rise portion104wire ends108. The ring120diameter is larger than the diameter of the buccal tubes114and prevents the device100from sliding toward the back of the mouth. The rings120are permanently fixed to the arch wire101with a solder or adhesive. In some embodiments the rings120are removably attached to the arch wire101. For additional anterior-posterior movement, washers122are interposed between the buccal tubes114and rings120. The washers advance the arch device forward and induce a larger separating force in the device which is applied to the rear teeth. Depending on the desired advancement of the device multiple washers are added or removed.

With reference toFIG. 3C, the secondary attachment means/auxiliary buccal tubes118are adapted to accept standard 18×25 wire113used for braces111.

In some cases it may be desirable to provide an additional anchoring point for the arch wire101. With reference toFIG. 4A-4B, auxiliary wires116are attached to the arch wire101adding an additional anchoring location of the device to the teeth to prevent rotation. The auxiliary wires116are attached approximately 7-12 mm from each end108A and108B, of the rear portion106and before the rise portion104of the arch100. Auxiliary buccal tubes118are additionally fixed to the molars or attachment bands112and are adapted to receive the auxiliary wires116.

In accordance with one aspect of the disclosure the auxiliary wires are round and are the same size as the main arch wire. In accordance with another aspect of the disclosure the round auxiliary wires are a smaller size than the main arch wire and range from 0.010 to 0.050 inches in diameter. According to another aspect of the disclosure, the round auxiliary wires are between 0.010 and 0.020 inches in diameter.

With reference toFIG. 4B, rings120are fixed to the arch wire101between the attachment point of the auxiliary wires116and end portion108. The ring diameter is larger than the diameter of the buccal tubes114and prevents the device from sliding toward the back of the mouth. The rings120are usually permanently fixed to the arch wire101with a solder or adhesive. In some embodiments the rings120are removably attached the arch wire101.

In some embodiments, as shown inFIG. 4C, for additional anterior-posterior movement, washers122are interposed between the buccal tubes114and rings120. The washers advance the arch device forward and induce a larger separating force in the device which is applied to the rear teeth. This separating force results in the posterior movement of the rear teeth, thereby increasing the space between the teeth in the anterior-posterior plane.

During development and as illustrated inFIGS. 5A-5C, rings120were fixed to the rear portion of the device, separating the front102and rise portions104of the arch from the rear portion108for attachment. The ring diameter was larger than the diameter of the buccal tubes114and prevented the device100from sliding toward the back of the mouth. In these embodiments, the rings120also provided a location for the attachment of auxiliary wires116. For additional anterior-posterior movement, as illustrated inFIG. 5C, washers122were interposed between the buccal tubes114and rings120. The washers122advanced the arch forward and induced a larger separating force in the device which is applied to the rear teeth.

The cross-section of the arch wire101is chosen for its ability to resist rotation and for its comfort level. The cross-sections are selected from but are not limited to, the cross-sections shown inFIG. 6. WhileFIG. 6illustrates the openings and shape of the interior of the corresponding buccal tubes, it is understood that an arch wire101to be inserted in the buccal tube114will be of a matched shape. The shapes shown inFIG. 6show a substantially D-shaped cross section, a substantially H-shaped cross-section, a substantially X-shaped cross-section, a substantially +-shaped cross-section, a substantially rectangular cross-section, a substantially circular cross-section, and a substantially oval cross-section. The buccal tubes114are adapted to engage the chosen arch wire cross-section shape.

Referring to FIG.7, according to some embodiments, the attachment means can include an attachment band112that is secured around the circumference of the molar110. The attachment means includes buccal tubes114S designed and shaped to accommodate the insertion of a correspondingly shaped arch wire101S, the cross-section as shown in FIG.8. The attachment means also includes additional buccal tubes118S that are designed and shaped to accommodate the insertion of correspondingly shaped auxiliary wires116or braces wire113.

In accordance with one aspect of the disclosure and as shown inFIG. 8, the rings120S can be shaped to provide comfort to the patient. The inner facing surface can be either flat or concave to match to a patient's gingiva while the outer facing surface can be a convex surface facing the buccal and labial vestibular tissue.

In accordance with another aspect of the disclosure, the front and rise portions,102and104respectively, of the arch wire101S include inner facing surfaces toward to gum, and outer facing surfaces toward the lip and cheek, as shown inFIG. 8, wherein the inner facing surface can be either flat or concave to match to a patient's gingiva while the outer facing surface can be a convex surface facing the buccal and labial vestibular tissue. The rear portions106of the device include cross-sections that are the same as the front portion102or are different and selected from, but not limited to the group including a substantially D-shaped cross section, a substantially H-shaped cross-section, a substantially X-shaped cross-section, a substantially +-shaped cross-section, a substantially rectangular-shaped cross-section, a substantially circular-shaped cross-section, and a substantially oval-shaped cross-section.

Referring now toFIG. 9, in accordance with another aspect of the disclosure, the orthodontic device100further includes an elongated appendage130adapted to engage the front portion102of the arch wire101, wherein the elongated appendage130extends into and pushes against the labial musculature of a patient. Presence of the arch wire pushing into and against the labial musculature activates the stretch reflex property of the muscle. The addition of the appendage increases the surface area of the arch wire and increases the muscle response. The more the muscle is stretched the more it pushes back. This effect drives the molars posteriorly as effectively as cervical pull from the outer bow of a face bow Kloehn device. When coupled with the advancement of the arch wire101through use of washers122, the additional surface area and resulting musculature push back results in the posterior movement of the rear teeth, thereby increasing the space between the teeth in the anterior-posterior plane.

In accordance with one aspect of the disclosure, the elongated appendage130is made of plastic. In accordance with another aspect of the disclosure a material such as nylon can be molded, fused, or bonded to the wire to create the appendage.

In accordance with another aspect of the disclosure the elongated appendage130can be designed such that it can snap fit to the arch wire101.

A method or process of treatment for expanding a patient's palate can progress as follows: First the arch size of the patient is measured. A wire or string spanned from molar to molar would measure the arch length. The measured arch length is then adjusted to add an additional length corresponding to the total size needed for the device's arch wire101. In most applications, the increase in length should fall into a range of 3-5 mm, with extremes of 1-10 mm. The wire is bent and the ends108A and108B are slideably engaged in buccal tubes attached to rear molars. Over time, while worn, the orthodontic device100can expand a patient's palate by a measure ranging from 8-12 mm. The patient would then be seen again by the Orthodontist, usually between every eight to ten weeks. If more adjustment/expansion is required, the radius of curvature of the arch wire is simply expanded by between 5-8 mm and reinserted into the tubes. The process repeats until the desired total expansion is reached. For some treatments it is desirable to replace the original arch wire with a new longer arch wire.

An early attempt to create a 100% efficient orthodontic device for the most abundant orthodontic case, Class I crowding, was to use a 0.045″ diameter expanded 18/8 steel arch wire. The ends of the main wire fit into 0.045″ buccal tubes that were anchored to a patient's rear molars. Here the tubes were attached to a metal anchoring band that wrapped around the circumference of a molar. Auxiliary wires were soldered to the main wire about 9-10 mm from each end of the wire. Auxiliary tubes were mounted to each anchoring band, above each 0.045″ buccal tube. The presence of the auxiliary wires and auxiliary tubes provided an additional location for molar anchoring. It was estimated that this device was 80-85% efficient.

To increase efficiency, simplify, and gain up to 100 percent performance that was lacking in the previous example, the 0.045″ diameter steel wires were pre-formed to five different parabolic shapes. Each pre-formed arch wire included a small ring attached to the wire about 7 to 10 mm from each end. The portion of the arch wire from the rings to the ends define the attachment portion of the arch wire while the portion of the arch wire in between the two rings define the working area of the arch. The attachment portion of the arch wire was beveled as it allowed easy slidable insertion into modified buccal tubes that were modified to have an internal anatomy identical to the form of the arch wire. The rings attached to the arch wire prevented over insertion of the device.

Presence of the arch pushing into the labial musculature activated the stretch reflex property of the muscle. The device was advanced further into the labial musculature by adding washers around the wires between the fixed wire rings and mounting tubes. The further the advancement, the more the muscle was stretched the more it pushed back. This effect drove the molars posteriorly as effectively as cervical pull from the outer bow of a face bow Kloehn device. Thus, this device accomplishes the task of the Kloehn device completely inter-orally and the external bow of the Kloehn device is no longer needed.

Having thus described the invention, it is now claimed: