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Publication numberUS3927664 A
Publication typeGrant
Publication dateDec 23, 1975
Filing dateNov 20, 1974
Priority dateNov 20, 1974
Publication numberUS 3927664 A, US 3927664A, US-A-3927664, US3927664 A, US3927664A
InventorsNicholas G Georgiade, Ralph A Latham
Original AssigneeUniv North Carolina
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Apparatus for use in the correction of maxillary and premaxillary conditions in infants
US 3927664 A
An arch alignment appliance for use in the correction of the maxillary and premaxillary deformity in infants with bilateral cleft lip and palate is achieved through the application of an intra-oral maxillary expansion and premaxillary retraction device capable of extra-oral operation. A screw mechanism is provided for expansion of the maxillary segments and for retraction of the premaxillary segments. Mucosal tissue damage is avoided.
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Description  (OCR text may contain errors)

United States Patent [191 Georgiade et a].


Ralph A. Latham, Chapel Hill, both of NC.

University of North Carolina, Chapel Hill, NC. by said Ralph A. Latham Filed: Nov. 20,1974

Appl. No.: 525,508


US. Cl. 128/76 R; 128/17 Int. Cl. A61F 5/00 Field of Search 128/76, l2, 17, 20, 345;

References Cited UNITED STATES PATENTS Davis 128/17 Dec. 23, 1975 2,587,245 2/1952 Terre 128/12 3,241,550 3/1966 Gelarie 128/12 3,454,001 7/l969 Stockfisch 128/76 R Primary Examiner-Richard A. Gaudet Assistant Examiner.l. Yasko Attorney, Agent, or Firm-B. B. Olive [57] ABSTRACT An arch alignment appliance for use in the correction of the maxillary and premaxillary deformity in infants with bilateral cleft lip and palate is achieved through the application of an intra-oral maxillary expansion and premaxillary retraction device capable of extraoral operation. A screw mechanism is provided for expansion of the maxillary segments and for retraction of the premaxillary segments. Mucosal tissue damage is avoided.

7 Claims, 7 Drawing Figures US. Patent Dec. 23, 1975 FIGK APPARATUS FOR USE IN THE CORRECTION OF MAXILLARY AND PREMAXILLARY CONDITIONS IN INFANTS CROSS-REFERENCE TO THE. RELATED APPLICATION This application relates to and constitutes an improvement over copending application Ser. No. 489,813 entitled Apparatus For Use In Treatment Of The Bilateral Cleft Lip And Palate Condition In Infants. of which one of the co-inventors of the present application was sole inventor.

BACKGROUND OF THEINVENTION cations, Ser. No. 489,813 and to which reference may.

be made. For immediate reference to. this invention much of such discussion will be repeated here.

The markedly protruding premaxilla and its positioning in the maxillary arch in severe bilateral clefts has been a topic of varied discussions, publications and devices for many years. Heretofore, external traction has been cumbersome, difficult to maintain and, if applied with too much tension, has caused loss of the soft tissue elements of the philtrum.

Various surgical reduction methods and devices for sectioning and repositioning the vomer are available; however, this has led to an unstable premaxillary segment in some patients and eventual tilting of the premaxillary segment lingually with resultant malposition of the permanent incisor teeth in others. Decreased growth of the premaxillary segment has also been a consideration following wedge resection of a portion of the vomerjThe surgical lip adhesion" technique, described for gradual retro-positioning of the premaxilla, necessitates one or two additional operative procedures prior to the actual lip repair and is unreliable.

A method, which introduces an intra-oral approach was introducedbyone of the co-inventors hereof, Dr. Nicholas G. Georgiade of Duke University Medical Center, Durham, North Carolina, in 1968. This utilizes Kirschner pins which are inserted through the cheeks, under local anesthesia, in the posterior maxillary area distal to the tooth follicles; The excess Krichner wire is then cut allowing sufficient wire to be present in each buccal sulcus so that the ends can be bent with thin nosed pliers in the shapes of hooks for rubber band fixation. If the patient has a complete palatal cleft associated with the premaxillary protrusion, rubber bands can f be placed around the Kirschner wire half-way across the palatal cleft, facilitating their attachment to the anterior hooked wire. This interior wire is inserted with a hand drill through the buccal aspect of-the' premaxilla in the region of the naso maxillary curves-Adequate lengths of wire are allowed to remain for hook formation at either end similar to that performed on the posterior maxillary wire. At this point, therubber maxillary segment also utilizes intra-oral traction to pull the segment back into its proper relationship in the maxillary aarch. Under local anesthesia, a Kirschner wire is inserted through one cheek just back of the maxilla. The wire is posterior to the location of any possible tooth follicles.

. The patients mouth is opened to facilitate insertion 'of the wire which is then advanced until the correct alignment is attained, as judged by its posistion just under the soft palate cleft. The Kirschner wire then drilled laterally on through the opposite maxillarypterygoid area until it is palpable in the opposite cheek. It is then cut as short as possible, so that soft tissues of both cheeks will cover the wire. A strip of Dacron is cut down the middle for half its length to create a Y-shaped sling. One limb of the Y is threaded across the anteriorsuperior surface of the ptemaxilla subcutaneously, under the prolabium as close to the bone as possible and superior to the point of the most forward position of the segment. The second limb of the Y is placed over the lower anterior (labial mucosal) aspect of the premaxilla and the, two previously separated ends are now sutured together with nylon. This makes it one continuous single band again, creating a length of Dacron on either side of the premaxilla, topull on a double sling over the bony segment. A standard rubber band is cut then at one end, threadedithrough each of the Dacron sling, and broughtaround the posterior Kirschner wire. The rubber band is now re-united to exert sufficient traction on the anterior segment, as judged by the tension on the tied rubber band. The two cut ends of the rubber band are'sutured together with silk, using two small mosquito clamps to grasp them and advance both of them until sufficient traction has beenobtained. This traction can beadjusted at the time of the lip repair to compensate for the interval retropositioningof the premaxillary segment. 1

lntra-oral rubber bands have now been used in many patients and have achieved what was expected of them, namely, a one-stage closure of the lip, and in some cases closure of the alveolar arch as well. However,

rubber bands lose their elasticity when used in the mouth and their tension is reduced as retraction occurs. Ideally, they should be replaced every two days. The continuousunremitting pull of rubber bands does not represent. the, best means for obtaining the most rapid movement when considered in terms of the collagen adjustment mechanism involved. A method and apparatus which accomplishes the desired movement in a series of steps, employing intermittent force IS thus much to be desired.

substantial advance in the art. However, use of the prior apparatus has indicated the need for improve ments directed to simplifying the construction, reducing irration to the mucosal tissues and improving the utility of the expansion portion of the apparatus as an bands are applied and traction instituted, either directly posteriorly, or along the buccal aspect, depending on the cleft type. Twin oral pin fixation and traction independent device. Thus, the present invention has these improvements in mind as a general objective and further seeks to provide for the satisfactory management of not only the premaxillary segment but the maxillary aleveolar arch as a whole.

SUMMARY OF THE INVENTION The apparatus of this invention, like that of the copending application, provides for incremental and intermittent retraction of the premaxilla and expansion of the maxilla, either independently or together. In the embodiment disclosed, a pair of intra-orally positioned control shafts, one within the other, extend outward the length of the oral cavity. Each control shaft has a knob which can be rotated extra-orally to impart the desired expansion or retraction reaction within the cavity. An intra-oral universal joint receives the shafts. The universal joint drives another threaded shaft which mounts a theaded block. The block slides in a housing. A pair of pivotal arm members pivot on arm extensions of the housing and are positioned by movement of the block which in turn is driven by the universal joint. These arm members, when the apparatus is in service, are secured, as with the apparatus of the copending application, to the maxilla segment through a pair of plates made integral with the lateral palatal segments of the maxillae by appropriate staple pine. A saddle or U-shaped premaxillary yoke rides, through a screw arrangement, back and forth on the outer control shaft. The U-shaped yoke is secured by pin means to the premaxillary seg ment. Rotation of the outer control shaft causes the U-shaped yoke to move in or out and effectively causes the premaxillary bony segment to be repositioned to a more normal position. While being internally mounted within the patients mouth, the apparatus is externally activated and, if desired, either function, i.e., retraction or expansion, may be obtained independent of the other. When the retraction function is of primary interest, the inactive expansion members attached to the maxilla simply serve as an anchoring means and when expansion is of primary interest the mentioned yoke and outer control shaft act merely as a support for the inner controll shaft. The mentioned universal joint, block and housing arrangement reduces irritation of the mucosal tissue and provides a somewhat simpler construction as compared to the apparatus of the copending application.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of the present invention apparatus for use in maxillary arch alignment with the apparatus being shown as it is installed in the mouth cavity for use.

FIG. 2 is a plan view of the apparatus of FIG. 1.

FIG. 3 is a side elevation view of the apparatus of the present invention.

FIG. 4 is a sectional view taken along line 44 of FIG. 2.

FIG. 5 is a perspective view of the screw block which is used in the present invention to activate the arm members shown in dashed lines.

FIG. 6 is a perspective view of a housing member which receives the screw block and which also mounts the arm members.

FIG. 7 is a perspective view of the screw block equipped with a cap for turning with a mating wrench.

FIG. 8 is a fragmentary elevation view of the saddle arrangement.

DESCRIPTION OF-THE PREFERRED EMBODIMENT The improved intra oral maxillary arch alignment apparatus of the present invention, generally designated by numeral 10, is illustrated as being adapted for extra-oral activation.

A universal joint assembly 11 is integrally secured to one end of a shaft member l3 which itself is mounted within an externally threaded hollow shaft 12 in a manner enabling shafts 12 and 13 to each be rotated independent of the other, shaft 12 to be free to slide outwardly on shaft 13 and shaft 13 to extend, at its free end, beyond the end of shaft 12. Shaft 12 has integrally secured to its extra-oral, free end a knurled knob portion 15 which as shown in FIG. 4 is secured to shaft 12 he means of a set screw 16. A second knurled knob 18 is secured to the end of shaft 13 by set screw 19. A relatively easily compressed coil spring 17 mounts and is compressed between knobs l5 and 18 on that portion of shaft 13 which extends beyond knob 15. Spring 17 thus pushes against knob 15 and in turn forces shaft 12 to slide inwardly on shaft 13 and against the face of universal joint 11. Spring 17 should preferably be at least slightly compressed when knobs 15 and 18 have their maximum spacing and should be compressible when knob 15 is turned to decrease such spacing.

Prior to placing knobs 15 and 18 and spring 17 on their respective shafts, a saddle arrangement 20 is placed on shaft 12. Saddle arrangement 20 is composed of two U-shaped plates 20, 20 secured together by screws 54, 55. Plate 20 has a non-threaded hole 21 which slides freely on shaft 12. Plate 20" has a threaded hole 21" which mates hole 21' and receives threaded shaft 12. Thus, when plates 20', 20" are secured together to form saddle 20 and plate 20" is threadably mounted on shaft 12, saddle 20, if prevented from rotating, can be caused to move back and forth along shaft 12 by turning knurled knob 15. A U-shaped yoke portion 22 of saddle arrangement 20 is adapted to be pinned to the premaxillary bone segment by a pin 53 passing through the segment and through slots 23', 23" of yoke portion 22 of saddle arrangement 20. Pin 53 is positioned within slots 23', 23" by loosening screws 54, S5 and sliding plate 20' as required after which screws 54, 55 are tightened so that pin 53 becomes clamped between plates 20, 20". Such pinning by pin 53 thus fixes saddle 20 against rotation and provides a fixed point to hold the premaxillary segment as it is being retracted and it can be seen that the provision of knob 15 on shaft 12 at its end opposite universal joint assembly 1 1 enables extra-oral rotation of shaft 12 to be translated into linear movement of the saddle arrangement 20 relative to shaft 12.

A T-shaped block 24, see FIG. 5, has a threaded passage 25 which extends completely through central body portion 26 of the block 24, Passage 25 receives a relatively short threaded shaft 27. One end of shaft 27 is integrally secured to the end of universal joint 11 which is opposite the end of universal joint 11 that is integrally secured to shaft 13. Rotation of shaft 13 thus acts to rotate universal joint 11 which rotates shaft 27 and causes block 24 to move him out depending on the direction of rotation.

As best seen in FIG. 6, a housing member 30 is formed of sheet metal, or the like, and has a base 31, back 32, top 33, and downwardly extending side members 34, 35. A pair of integrally formed arms 36, 37

extend outwardly from base 31 and reside in a common plate parallel to and above base 31. Arms 36, 37 have respective apertures 38, 39. Base 31, back 32, top 33, and sides 34 and 35, extending down apredetermined distance as extensions of top 33, form a cavity 40 which is sufficiently large to house and slidably receive the previously mentioned T-shaped block 24. A pair of crank arms 43, 44 mount respective pins 41, 42 which rotate in the respective apertures 38, 39 thereby enabling arms 43, 44 to pivot on the arms 36, 37. The outer ends 47, 48 of arms 43, 44 "operate in a common plane parallel to and above base 31 of housing 30. The inner ends 45, 46 of arms 43, 44 occupy a lower common plane above and near base 31 and extend into housing through slots 47, 48 as best seen in FIG. 6.

T-shaped block 24 is placed into housing 30 so that back 28 of block 24 is substantially adjacent to back 32 of housing 30. At this point, arms 43, 44 are rotated on pins 41, 42 until their respective inner ends 45, 46 are extending into cavity and rest against front 29 of block 24. As later explained, the outer ends 47, 48 of arms 43, 44 are adapted to receive, e.g., by molding thereto, a pair of plastic plates 49, 50 which are secured to the maxillary segments and are molded to conform to the segments.

The description will next refer to the insertion and operation of the intra-oral maxillary arch alignment apparatus 10 which is the subject'of the invention. In preparation of insertion, an impression is taken of the maxillary and premaxillary segments. A pair of plastic plates 49, 50 are molded from the impression so that plates 49, 50 fit as near perfectly as possible over the maxillary segments. in the molding process, each plate 49, 50 is preferably molded around a respective offset outer end portion 47, 48 of arms 43, 44 so that each respective arm end and associated plate effectively become an integral unit. In order to mold the retaining staples 51 into plates 49, 50, the apparatus is placed so that the pivot points established by pins 41, 42 are over the maxillary tuberosities with the segment arms 43, 44 in the fully closed position. The position of the retaining 51 is marked on the palatal area and holes are then drilled into the plastic to accept the staples 51 which in one embodiment have been made of 0.030 inch high tension stainless steel wire. The points of the staples are oriented laterally and somewhat anteriorly so that expansion and retraction forces will be withstood. Prior to insertion, the appliance is sterilized and with staples SI partly inserted into plates 49, 50, the apparatus is positioned in the mouth. Tongue and cheek'retractors are employed-as needed during insertion of the invention apparatus 10. When apparatus 10 is in proper position so that plates 49, 50 mate with the proper maxillary bone area, staples 51 are driven level with plates 49, 50 so that the apparatus becomes attached to the maxillary bone.

Next, saddle arrangement 20 has to be positioned in the desired spot along the posterior premaxillary stern. Correct'location of premaxillary pin 53 is probably the most exacting procedure. The location is first determined on a lateral dental radiograph of the septopremaxillary segment and should preferably be in the basal premaxillary bone just posterior to the dental crypts and well anterior to the premaxillo-vomeral suture. Measurements from the labial mucosal outline and from the inferior mucosal outline to the marked position on the radiograph serve to establish the correct point for insertion of pin 53 in the patient. Premaxillary pin 53 is obtained, for example, from an 0.035 inch Kirschner wire and after being drilled through the premaxillary bone, pin 63 is cut to the width of yoke 22. The coaxial shaft arrangement and the saddle arrangement are placed in the patients mouth at the time of the original insertion of the expansion component so that the T-shaped block 24 fits properly into housing 30. Yoke portion 22 is then engaged onto pin 53 by loosening screws 54, 55 and allowing slots 23', 23" to slide down over pin 53. Once in place, screws 54, 55 are tightened thereby holding pin 53 between plates 20', 20" in slots 23', 23" by being clamped.

Now, by rotating knob 18, the maxilla bones may be gradually expanded as desired. Once knob 18 is rotated, shaft 13 and integral universal joint assembly 11 are rotated. Universal joint 11 adapts the apparatus to a deviated septopremaxillary segments, and allows freedom of movement to the premaxillary segment as it responds to tractional force. For expanding the maxillary segments, rotation of universal joint assembly 11 causes shaft 27 to rotate and effectively moves T- shaped block 24 back away from the interior of the mouth. As block 24 moves outward on shaft 27, arm

. ends 45, 46 tend tobe moved outward away from back plate 32. Since plates 49, 50 are molded integral with arm ends 45, 46 and since plates 49, 50 are attached to the maxillary bone by staples 51, the outward movement of arm ends 45, 46 effectively expands the maxillary bone segments. For example, a time schedule may be established for precise, measurable and controllable incremental changes in the expansion. The coil spring 17 which mounts between knobs l5 and 18 is compressed as the space between the knobs decreases. Thus, spring 17 effectively provides'a visual gauge and may be used to register, when in operation, the retraction force so that the load placed upon the premaxillary bones may be maintained with safe limits.

In a specific apparatus embodying the present invention, one turn of knob 18 has been effective to expand the maxillary bone segments 1 mm. In the same embodiment, each rotation of knob 15 acts to retract saddle arrangement'20 and consequently to retract the ment of the cleft segments which can be immediately followed through with a gingivoperiosteoplasty at the same time as lip repair. Thus, bone can be expected to grow into the cleft, unifying the upper jaw and stabilizing the alignment of the maxillary arch. Such conditions are favorable for subsequent growth to follow a normal pattern. In this way, it is hoped to avoid crossbite malocclusion and to render long term use of intraoral retention appliances unnecessary.

In summary, it can be seen that while the present invention apparatus operates basically like the apparatus of the prior invention, a number of improvements are evident. In particular, the universal joint-blockhousing arrangement eliminates exposing mucosal tissue to the ends of rotating shafts-as sometimes occurred with the prior apparatus. The universal joint also provides a much desired flexibility for meeting the numerous kinds of cavity conditions encountered in infants. As previously mentioned, the expansion apparatus of the present invention can be used independent of the retraction apparatus. Where retraction is of no particular interest, block 24 may be driven as illustrated in FIG. 7. Thus, shaft 27 of FIG. 5 may be modified as represented by shaft 27' in FlG. 7 to include a recessed cap 55 with a recess 56, e.g. hexa'gon'al such that shaft 27' may be turned with a mating tool 57. This concept of using the expansion apparatus independently can be further visualized by noticing that the expansion structure of FIG. 6 when equipped with the intraoral drive structure of FIG. 7 represents such an independent expansion device. Parents can be taught to make the necessary adjustments with the FIG. 7 arrangement. Thus, treatment of the infant can proceed out of the hospital and at a substantial reduction of cost of the patient.

What is claimed is:

l. A mouth cavity maxillary bone correction apparatus, comprising:

a. a pair of elongated laterally spaced arm members having outer end portions residing in a common plane and adapted for intra-oral placement and securement to corresponding laterally displaced maxillary bone and opposite inner end portions adapted to extend intra-orally from such securement;

b. a pair of plate means molded to conform and to be secured to ,said bone, said plate means being secured to respective said arm member outer end portions thereby adapting such outer end portions to be secured to said bone;

c. housing means adapted to be intra-orally placed and formed by connected walls and positioned between and rearwardlyof said plate means, said housing providing integral outwardly extending portions for making pivotal connections with medial portions of said arm members enabling said arm members to be pivoted thereon, said housing walls being formed to receive the respective said arm member inner end portions within said housing and to allow corresponding reciprocal movements therein;

. screw block positioning means adapted to be intraorally placed and slidably mounted and confined within said housing such that said positioning means is isolated from any surrounding mucosal tissue during use thereof, said positioning means being between and having surfaces loosely engaged with said inner end portions of each of said arm members to control the positioning thereof, said positioning means having a shaft drive enabling said inner end portions to be moved in an extraoral direction to effect corresponding outward pivotal movements of said arm member outer end portions; and e. drive means including a drive shaft having one inner end adapted to be intra-orally placed and connected to drive said positioning means by the turning of said drive shaft and having the other outer end thereof adapted to be extra-orally placed and adapted for finger engagement to effect rotation thereof whereby as said drive shaft is rotated in an appropriate direction and with respective said arm member outer end portions secured to said bone through said plate means, the lateral spacing of said bone may be increased to effect appropriate correction thereof.

2. An apparatus as claimed in claim 1 including a securing member adapted to be intra-orally mounted and having an end portion adapted to be fixedly secured to the premaxillary segment and an internally threaded body portion formed integral therewith an auxiliary externally threaded hollow shaft having one inner end adapted to be intra-orally placed and being rotatably mounted on and rotatably independent of said drive shaft, the opposite outer operating end of saidauxiliary shaft adapted to-be extra-orally placed and adapted for finger engagement thereof with the central portion of said auxiliary shaft being threadably mounted in said securing member body portion such that with said one end of the securing member pinned to said segment and with said arm members secured to said bone, said segment and bone may be moved relatively, bi-directionally, and incrementally for cleft lip and palate correction by corresponding extra-oral rotation of said outer operating end of said auxiliary drive shaft.

3. An apparatus as claimed in claim 2 including a coil spring mounted between the respective outer ends of said drive and auxiliary shafts and being compressible according to the amount by which said auxiliary shaft is turned and the distance between said outer ends is decreased as a visual gauge of the amount of said correction.

4. An apparatus as claimed in claim 1 wherein said drive shaft outer end is formed as a removable drive shaft member adapted to be detachably secured to the inner end of saiddrive shaft when needed for turning the inner end of said drive shaft.

5 An apparatus as claimed in claim 1 wherein said outer and inner drive shaft ends are connected through a universal joint.

6. An apparatus as claimed in claim 2 wherein said outer and inner drive shaft ends are connected through a universal joint.

7. An apparatus as claimed in claim 6 wherein for purposes of being fixedly secured, said securing member end portion is adapted to receive and to be clamped to a pin passing through said premaxillary segment.

QETEFIQATE GP @QECHGN Patent No. 3 27,664 Dated December 23, 1975 Inventor(s) Nicholas G. Georgiade; Ralph A. Latham It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Immediately following the title the following paragraph was omitted in the patent:

The invention described herein was made in the course of work privately funded and also partially supported under a grant or award from the Department of Health, Education and Welfare. The United States Government is granted a nonexclusive, royalty free license to make, use and sell for governmental purposes under any patent issuing herefrom.

Col. 1, line 24, "cations" should be --cation--.

Col. line 52, "Krichner" should be --Kirschner--.

Col. 2, line 13, "posistion" should be --position--.

Col. line 31, -end-- should be inserted after "each".

001. line 25, "pine" should be -pins-.


Col. 3, line 41, "controll" should be -control-.

5, line 2, "plate" should be --plane-.

Col. line 42, -staples-- should appear after "ing" and before "51''.

C01. 6, line 17, "segments" should be -segment--.

heel of 2 UNITED STATES PATENT OFFICE ttTmcATE 0F CORRECTION patent NO 3,927,664 Dated December 23, 1975 Inventor(s) Nicholas G. Georgiade; Ralph A. Latham It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 7, line 1.1, the second appearance of the Word "of" should be -to-.

C01. 8, line 15, a comma should be inserted after "therewith".

Signed and Scaled this eighth Day of June 1976 qsmm Arrest:

RUTH C. MASON C. MARSHALL DANN Alreflinx Offifl" Commissioner affluent: and Trademarks

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US815907 *Mar 27, 1905Mar 20, 1906Cleveland G DavisDental expander or dilator.
US2587245 *Jan 6, 1950Feb 26, 1952Terre Victor JCombined mouth speculum and tongue support
US3241550 *Nov 5, 1963Mar 22, 1966Louis GelarieMouth retractor
US3454001 *Jun 3, 1965Jul 8, 1969Hugo StockfischOrthopedic treatment apparatus for the jaw bones
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4700695 *Aug 11, 1986Oct 20, 1987Davis Christopher LMandible motion apparatus
US6176859 *Feb 23, 1999Jan 23, 2001Paul A. MullerPulling apparatus for correcting a jaw
US7485121May 4, 2004Feb 3, 2009Synthes (Usa)Midface distractor
US8172849Dec 19, 2008May 8, 2012Synthes Usa, LlcMidface distractor
U.S. Classification606/54, 600/237
International ClassificationA61C7/10, A61C7/00
Cooperative ClassificationA61B17/663, A61C7/10
European ClassificationA61C7/10, A61B17/66J