in referring to the drawings , fig1 shows the present invention installed about the teeth of the upper or maxillary jaw of a person . the present invention comprises a mouthpiece 1 generally arcuate in shape made of a polymer material , often transparent . the mouthpiece has two wings 2 , left 2 a and right 2 b , that join at the midpoint 1 a of the mouthpiece . a wing begins where it fits over a molar 3 and then curves and narrows forward toward where it fits over an incisor 4 . the mouthpiece fits snugly upon the outside of the teeth . the mouthpiece has preprogrammed features that contact the teeth to straighten them as done with the invisalign ® series of mouthpieces . the wings have a generally u shape in cross section that is sized to fit snugly upon the various teeth in the jaw . the wings are modeled with computer programs for precise fit and sizing . the mouthpiece using the wings straightens teeth and moves them into a desired arcuate form . however , the wings of existing mouthpieces do not provide for lateral expansion of the arch by spacing apart the molars . within the wings shown in fig1 , the present invention has an expander 5 as originally shown in my previous application , ser . no . 10 / 439 , 638 and which is incorporated herein by reference . the expander has a housing 6 with an advancing member 7 telescoping axially from within the housing . the housing joins to the left wing 2 a shown in fig1 proximate to where the left wing fits over the molars 3 . the housing has a generally rectangular shape in cross section that extends across the width of at least two molars . the housing has side walls , a top 8 , a bottom , a back 9 and an open front 10 . a channel 11 extends rearward from the front edge of the outer housing . a threaded rod 12 extends forwardly from the housing back wall 9 to the front 10 . the threaded rod extends along the center of the housing and rotates axially within the channel 11 . then an advancing member 7 is slidably received within the housing 6 . opposite the housing , the advancing member joins to the right wing 2 b of the mouthpiece . the member also has side walls , a bottom , a top , and a front wall 13 though of slightly less dimensions than the counterparts in the housing to permit fitting within the housing . a channel extends partially along the center of the top and cooperates with the channel in the housing to permit access therethrough to the threaded rod 12 within the housing . next , an internally threaded activation nut 14 operates upon the housing &# 39 ; s threaded rod . the nut has a size so that its peripheral edge is accessible through the channels 11 of the housing and the advancing member . the nut has a plurality of radial holes 15 spaced upon in its periphery . the holes are also accessible through the channels using a key , or tool , ( not shown ) to rotate the nut thus moving it along the rod . the nut advances an activation wing ( not shown ) within the housing and towards the advancing member . the activation wing is located in front of the activation nut 14 for movement by it . the wing is journaled about the threaded rod and extends laterally to provide support for a spring 16 upon each end of the wing . the springs extend from the wing to the front wall of the advancing member . the springs provide an expansive force that moves the advancing member outwards and away from the housing . as can be appreciated , the springs supply their expansive force as the activation nut turns upon the rod . turning of the nut 14 advances it along the rod 12 generally towards the center of the expander . the nut then moves the wing along with it , urging the springs to expand upon the advancing member . in doing so , the advancing member 7 and housing 6 impart lateral outward forces upon the molars 3 on each side of the maxillary jaw . over time , the lateral forces widen the jaw as prescribed by the orthodontist . viewing the present invention from the side in fig2 , the mouthpiece has an apparent rectangular shape with rounded edges . the mouthpiece fits over the teeth of the maxillary jaw with the upper edge of the mouthpiece approaching the gum tissue . here the left wing 2 a of the mouthpiece is shown , extending from the incisors or midpoint 1 a to the molars 3 . the transparent mouthpiece shows the housing joined to the inner surface of the mouthpiece in the vicinity of the molars . the housing 6 has a generally rectangular cross section as previously described with the perimeter of the housing joining to the mouthpiece . the advancing member 7 nests within the housing and moves outward upon the wing as the nut turns upon the rod 12 . the housing and the advancing member join to the mouthpiece by fusing to existing aligners by heating or chemical welding . the operations of the present invention in cooperation with a mouthpiece 1 are shown via a rear view of the mouthpiece in fig3 . as previously described , the mouthpiece has a generally u shaped cross section so the left wing 2 a and the right wing 2 b fit over the teeth . the mouthpiece fits over the biting edge of the teeth and extends towards the gums . the housing joins to the left wing and the advancing member joins to the right wing , both proximate to the rear molars 3 . the advancing member fits snugly within the housing . springs 16 engage the advancing member outwards to expand the jaw . the springs extend into the expander onto a wing 17 . the wing 17 as previously described is ahead of the activation nut 14 . the nut 14 is turned upon the rod . in turning the nut , the expander converts the rotation of the nut into an axial expansive force transferred through the housing and the advancing member to expand the maxillary arch laterally . an alternate embodiment of the expander is shown attached to the palate of a patient in fig4 , as an alternative to mounting the expander upon a mouthpiece . the maxillary jaw has teeth arranged in a generally arcuate shape with molars 3 towards the rear of the jaw and incisors 4 towards the front . the teeth are generally arranged symmetrically about a line 4 a extending from between the two incisors to half way between the molars . this line follows the palate 4 b , or upper roof of the mouth , of a patient . the palate is made of bone and is an integral part of the patient &# 39 ; s skull . in younger patients and over longer durations in adult patients , bone can grow or be moved . the alternate embodiment utilizes the housing 6 and advancing member 7 along with internal hardware of rod 12 , wing 17 , activation nut 14 , and springs 16 as previously described . the housing and advancing member each have a grommet 18 in the alternate embodiment . each grommet has a generally round shape joined tangent to the back of the housing and the advancing member respectively . the plane of the grommet is generally parallel to the plane of the housing . each grommet has a center hole 19 that seats a screw 20 . alternatively , the grommet is bent to conform to the surface of the patient &# 39 ; s palate . fig5 shows the components of the alternate embodiment of the expander in a partially exploded view . the housing has a partially circular grommet joined to the back wall and the advancing member also has a partially circular grommet joined to its respective back wall . each grommet has a rounded hole therethrough into which a screw turns for securement into the palatal bone during usage as later described . the grommets have a cross section along their circumference to permit snug seating of the screw upon the grommet thus reducing contamination by food and injury to the tongue by rough edges . in use , the alternate embodiment is positioned by the oral surgeon , or orthodontist , between the molars with the channel facing towards the tongue . with the patient sedated , the channel of the assembled expander is oriented perpendicular to the molars and the expander is centered within the palate . the grommets provide a template for drilling pilot holes into the bone of the palate . the pilot holes are then cleaned and prepared to receive surgical grade screws . the grommets are then positioned over the pilot holes and the screws are installed singly until the grommets are snug upon the palate . once the patient awakens , the patient is instructed on operating the expander and proper oral hygiene to keep the expander clean and to reduce the incidence of infection . variations or modifications to the subject matter of this development may occur to those skilled in the art upon review of the invention as described herein . such variations , if within the spirit of this development , are intended to be encompassed within the scope of the invention as explained . the description of the preferred embodiment and as shown in the drawings , are set forth for illustrative purposes only to show the principle of this maxillary arch expander not attached to a patient &# 39 ; s teeth .
an orthodontic arch expander joins to a mouthpiece proximate to the rear of the mouthpiece . the transparent mouthpiece has a desired arc that fits over the teeth of the upper jaw . the mouthpiece has two wings that join near the incisors and then become parallel and spaced apart around the molars . near the molars , an arch expander joins to the mouth piece . the arch expander has two telescoping shells with a threaded jack and cooperating springs . each shell joins to a corresponding wing of the mouthpiece . turning the jack lengthens a rod that pushes the shells outwards against the mouthpiece thus widening the maxillary arch without brackets or bands upon the teeth . an alternate embodiment has the arch expander attaching directly to the palatal bone through screws placed through a grommet at the end of each shell by an orthodontist or oral surgeon .