CA2207561A1

CA2207561A1 - Drilling catheter assembly

Info

Publication number: CA2207561A1
Application number: CA 2207561
Authority: CA
Inventors: David E. Gibbs
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-06-12
Filing date: 1997-06-12
Publication date: 1998-12-12

Abstract

A drilling catheter assembly comprising: a hollow drilling needle adapted to serve as a catheter affixed to a first flange at its non-drilling end; a second flange adapted at one side thereof to engage said first flange and adapted at its opposite side to engage a rotating shaft; and said first flange with affixed drilling needle and said second flange held together in an assembled position by means an outer protection housing open at its end near said opposite side.

Description

DRILLING CATHETER ASSEMBLY

BACKGROUND OF THE INVENTION

1. Field of the Invention The present invention is directed to a drilling catheter assembly for intra-osseous S delivery of medication and is particularly suitable for delivery of dental anaesthesia.
An intermediate assembly is provided by ~e m~mlf~cturer and comes sterile with a c~n~ ..in~l ion protective cap and, once used, the intermedi~t~ assembly may be simply disposed of. A preferably sterilizable stainless steel adaptor engages the intermediate assembly and interfaces it to the dental handpiece for drilling. Once drilling is 10 completed, the adaptor is removed leaving the drilling catheter component of the intermediate assembly in place for insertion of an injection needle therethrough to infuse the medication to the target site.

2. Related Art There are a variety of methods currently in use for providing local anaesthetic in 15 dentistry. These methods and appaldluses however all have disadvantages, either heing difficult for practitioners to perform or painful and unpleasant to the patient.

An example of a method used ~;ull~;;nlly in dentistry is the infiltration method, whereby a local anaesthetic solution is injected into the soft tissue of gingiva. In doing so, the solution eventually passes through the cortical plate affecting the nerve bundle entering the tooth. Disadvantages of this method include the delay of onset of anaesthesia after 5 the injection and, in most cases, ballooning of the injected tissue. As well, there is an extended period of time for recovery of the tissue until return to normal condition.

Another method which is cullelllly used is the regional block method whereby an anaesthetic solution is injected locally in proximity to the nerve trunk as it enters the bone. Disadvantages of this procedure are that it is extremely difficult to locate the 10 nerve trunk, there is discomfort to the patient and a delay for the anaesthetic to take effect. As in the case of the infiltration method, this method necessitates a long recovery period for tissue to return to normal.

At present, two types of a~ tus have been used to ~l rO~ intra-osseous anaesthesia. These are surgical burs used to perforate the cortical plate and the villet 15 injectors.

The use of a surgical bur has disadvantages in that burs are ~ el~ive and they have to be sterilized between uses or a new bur used each time. In addition, the method is slow, requiring the ~ h~d gingiva and periosteum to be anaesth~ d before the cortical plate is perforated. The villet injector is an appa-alus that services both as a CA 02207~61 1997-06-12 perforator and injector. It uses specifically designed needles rotated by a conventional dental motor. A disadvantage of this device is that the needle often becomes clogged with pulverized bone which obstructs the passage in the needle and prevent~s injection of the anaesthetic solution. It is generally difficult to remove the clogging material S from the needle and often the use of a second needle is necessary. Other disadvantages of this method include the initial capital cost of the instrument purchase, and the cost of the needles which are somewhat expensive. In addition, the design of the instrument makes access to various parts of the mouth difficult and sometimes impossible.

10 Intra-osseous and targeted root-canal nerve anaesthesia have not become popular for the reason that there has not heen a practical technique of making the injections successfully. For example~ there has been a general belief that this method is radical and to be restored to only if nerve block and infiltration anaesthetic do not accomplish the desired result. However, intra-osseous and targeted injections produce positive7 15 more ~roround anaesthesia and could be made with less pain than either of the other types according to the present invention.

Targeted . - ~sthe~i~ has several advantages over prior art nerve block or infiltration methods. There is no feeling of numbness in the tongue7 cheek7 or lips during or after the injection and there is no after-pain. The anaesthetic is profound and acts 20 immediately alleviating the necessity of waiting for the anaesthetic to take effect as CA 02207~61 1997-06-12 with the nerve block and infiltration methods. Furthermore, as only a few drops of anaesthetic are injected, there is no feeling of faintness or increa~sing of the pulse rate.

To achieve targeted anaesthesia one must gain access, if intra-osseous, to the cancellous bone by going through the cortical layer; or to the bottom of the booth, if S root-canal targeted an ~Sthf~ci~ is desired. Because of instant anaesthesia and profound pulpal ~n~esth~si~, there is a much greater control over the region one wishes to anaesthetize, resulting in a much smaller does of anaesthetic; as well as, of course, other medication, where applicable.

United States Patent No. 5,173,050 ~Dillon) discloses a dental appa-alus for 10 perforating the cortical plate of human m~xill~ry and mandibular bones. The appalalus of Dillon comprises a metal needle moulded into a plastic shank. The shank is being formed with means for cooperation with a dental hand piece for transmitting the rotational movement to the needle. The needle used for drilling is solid and has a sharp bevelled free end. The appa.~lus described by Dillon is disposable.

15 However, the device disclosed in Dillon's patent cannot be used as a catheter for injecting ~n:lesth~tic by inserting a hypodermic needle through the drilling needle. As well, the device disclosed by l~illon is not provided with means for blocking entry of bone debris into the needle passageway. In addition, the direct connection between the hand piece and the pelroIat(~r does not provide for a safe and reliable id~ntifi~hle passageway through which the ~n~esth~si;~ can be transported and is only available to use via the fixed gingiva.

In United States Patent No. 5,261,877 (Fine et al.) there is provided an intravascular c~th~,~er and thrombectomy procedure utili7ing the cathe~er. The catheter comprises S a flexible jacket with a distal working head having a c~n~ ing tip rotatable at high speeds for removing ~1I1V111I~US from the lumen of a vessel. A flexible drive assembly extends through the jacket to rotate the tip and a plurality of infusion ports are formed adj:lcent the distal end of the jacket, capable of delivering a fluid contrast media at relatively high volumetric flow rates into the lumen of the vessel to locate the site of 10 the ~hrolllbus. The c~n~1i7ing tip is then rotated at high speed to homogenize and remove the thrombus from the lumen.

United States Patent No. 3,534,476 (Winters) discloses a drilling and filling root canal app~lus. The drilling is performed by a drill having a central bore. The depth of the root canal is d~lellllh~ed in advance and a stop is placed on the drill to limit the 15 depth of drilling. The device is provided with a flexible rod which is pushed into the root canal so that the drill is directed along this road to follow the contour of the canal so that the resulting bore will have an uniform ~i~mf~tçr which is free of shoulders or leges. The al)pa.alus disclosed by Winters is concerned with enlarging the root canal after the nerve has been extracted. This apparatus is not used for injecting medication 20 in close proximity to a targeted area for tre~tm~nt or anaesthetic.

United States Patent No. 4,944,677 (A1exandre~ discloses a smooth hollow needle with a bevelled point for dAlling a hole into the jawbone near the apex of the tooth to be ~n~estheti7ed Theredfler, the drilling device 13 removed from the jaw, and a hypodermic needle of substantially the same gauge is inserted into the hole and 5 ~n~h~si~ is injected. Thus, there is no cath~ti7ed delivery of medication, with the ~tt~nd~nt disadvantage that the pre-drilled hole may be difficult to locate when inserting the hypodermic needle.

One significantly older United States patent that is discussed by Alexandre (above) is United States Patent No. 2,317,648 (Siqveland) granted in 1943. In addition to the 10 disadvantage mentioned by Alexandre, the fact that Siqveland teaches use of threaded sleeve which penetrates the bone during drilling and is left (screwed) in the bone to serve as a guide for insertion of the actual injection needle. I~ue to the cost of such a device, it cannot be made disposable; but more impo~ ly, for the threaded sleeve to be securely fastened in the bone it would have to rotate at a much slower speed than 15 the drill (as in Siqveland) or the drilling catheter (as in the present invention~.

SUMMARY OF THE INVENTION

The present invention provides a drilling clthftet assembly comprising: a hollow drilling needle adapted to serve as a cath~ter affixed to a first flange at its non-drilling end; a second flange adapted at one side thereof to engage said first flange and adapted at its opposite side to engage a rotating shaft; and said first flange with af~lxed drilling needle and said second flange held together in an assembled position by means an outer protection housing open at its end near said opposite side. The assembly may, however, be provided witbout the housing, which could, if desired, be added later.

S The dril1ing c?~het~qr assembly, said second flange having a dowel projecting from its centre and located inside of, and concentrically with~ said hollow drilling needle.

The drilling c~theter assembly, said dowel having a ~ m~ter such that it is easily withdrawn from said hollow drilling needle after drilling.

The drilling ca~he~qr assembly, said dowel being sufficiently long to prevent drilling l0 debris from blocking the hollow drilling needle once the dowel has been withdrawn.

The drilling catheter assembly, said first and second flanges having a lon,~itu(1in~1 groove for receiving a prong projecting from a third flange adapted its side opposite said prong to engage a drilling handpiece.

BRIEF DESCRIPTION OF THE DRAWINGS

15 The preferred embodiment of the present invention will now be described in conjunction with the anneYed drawing fgures, in which:

Figure 1 is an exp10ded view of the full drilling catheter assemb1y, including the handpiece interface adaptor;

Figure 2 is a partial cross-section of the fully assembly drilling cathPter shown in Figure l just prior to the removal of the co.~ ion protective cap; and 5 Figure 3 shows in more detail the upper left-hand corner of the assembly shown in Figure 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to Figures 1, 2 and 3 of the drawings (Figure l shows an exploded view) the full drilling catheter assembly comprises a co.~ 1ion protective cap 107 a IO hol10w drilling cathç~er 11 having a drilling tip 12 and afflxed at its other end to an oulward]y flaring flange 13 which te~ ates in an integral cylindrical portion 14, which has four (but preferably at least two) equal1y spaced longitudinal grooves or slits 15 in its wall. A cylindrical flange 16, adapted to engage the top of the cylindrical portion 14 in a fixed position by means of a protruding spur 17 and a co-operating lS notch 18 in the wall of the portion 14, is provided with four equally spaced longitudinal grooves or slits 19 in its wall which are aligned with the slits 15 (by means of the spur 17 and notch 18). The flange 16 has a theleli()lll centrally CA 02207~61 1997-06-12 protruding rod or dowel 20, which fits inside the hollow catheter 11 preferably reaçhing down to near the bevelled drilling tip 12. The components described so far represent the m~nuf~ct~rer assembled intermefli~te assembly, which is delivered contained inside the cap 10 and which is held together by the slight pressure of the S walls of the cap 10. The final part of the full assembly is disc-like flange 21, which has projecting therefrom four (or two or three, as ~e case may be) prongs 22 distributed equidistantly along the cil~;u~llrer~nce of the flange 21 to fit into the slits 19 and 15, the prongs 22 being slightly wider at their point of ~ hm~Mt to the circumference of the flange 21 and projecting slightly ~ulwaldly from the 10 cilcul~lrelence such that when the flange 21 is pushed down into the provided interme~ te assembly beyond the upper edge of the cap 10, the prongs 22 push-out the wall of the cap 10 at the points of contact 23 and, if the cap 10 had been creased along the points of contact 23, cause the wall of the cap 10 to rupture along the creases 23. At the same time, once the flange 21 has been pushed below the edge of the flange 16 (as shown more clearly in Figure 3) it is retained by lip portion 24 in the flange 16. With the flange 21 thus retained and the wall of the cap widened or ripped along the creases 23, it is then a simple matter to pull the cap 10 off while holding it and a shaft 25 protruding outwardly from the centre of the flange 21. The shaft 25 is, of course, adapted to engage the dental handpiece.

20 Once the cap 10 has been removed, the dental handpiece ~not shown) engage the shaft 25 and drilling is commenced according to normal practice. When drilling is completed, the cy1indrical portion 14 is pl~feldbly held between thumb and indexfinger while the handpiece is pulled away removing with it the flanges 21 and 16, with the c~th~t~r 11 left in place. It is then a simple matter of inserting an injection needle through the portion 14 and into the catheter l 1 to deliver the an~esthesi~ to the target 5 site. A1though the presence of the dowel 20 may not be always necessary, it is desirable in order to prevent bone debris from blocking catheter 11.

The entire interm~li~t~ assembly may be made from a (disposable) plastic material except, of course, for the drilling cath~ter 11 (and possibly the dowel 20). Thus, the interme(li~te assembly comes sterilized and protected from co~ ion in a 10 protective wrap (not shown) and is disposed of after use. The only part that is plerel~bly made from st~in1es.~ steel is the handpiece interface flange 21, which may thus be sterilized after use.

Claims

1. A drilling catheter assembly comprising: a hollow drilling needle adapted to serve as a catheter affixed to a first flange at its non-drilling end; a second flange adapted at one side thereof to engage said first flange and adapted at its opposite side to engage a rotating shaft; and said first flange with affixed drilling needle and said second flange held together in an assembled position by means an outer protection housing open at its end near said opposite side.

2. The drilling catheter assembly as defined in claim 17 said second flange having a dowel projecting from its centre and located inside of, and concentrically with, said hollow drilling needle.

3. The drilling catheter assembly as defined in claim 27 said dowel having a diameter such that it is easily withdrawn from said hollow drilling needle after drilling.

4. The drilling catheter assembly as defined in claim 3, said dowel being sufficiently long to prevent drilling debris from blocking the hollow drilling needle once the dowel has been withdrawn.

5. The drilling catheter assembly as defined in claim 1, said first and second flanges having a longitudinal groove for receiving a prong projecting from a third flange adapted its side opposite said prong to engage a drilling handpiece.

6. The drilling catheter assembly as defined in claim 5, said prong when fully inserted into said groove causing said outer protective housing to rupture at its open end.

7. The drilling catheter assembly as defined in claim 6, said protective housing having a crease in the vicinity of its open end to facilitate said rupture.

8. The drilling catheter assembly as defined in claim 5, said first and second flanges having a plurality of longitudinal grooves along their periphery for receiving a like plurality of prongs projecting from the periphery of said third flange.

9. The drilling catheter assembly as defined in claim 2, said first and second flanges having a longitudinal groove for receiving a prong projecting from a third flange adapted its side opposite said prong to engage a drilling handpiece.

10. The drilling catheter assembly as defined in claim 3, said first and second flanges having a longitudinal groove for receiving a prong projecting from a third flange adapted its side opposite said prong to engage a drilling handpiece.

11. The drilling catheter assembly as defined in claim 4, said first and second flanges having a longitudinal groove for receiving a prong projecting from a third flange adapted its side opposite said prong to engage a drilling handpiece.

12. The drilling catheter assembly as defined in claim 9, said first and second flanges having a plurality of longitudinal grooves along their periphery for receiving a like plurality of prongs projecting from the periphery of said third flange.

13. The drilling catheter assembly as defined in claim 10, said first and second flanges having a plurality of longitudinal grooves along their periphery for receiving a like plurality of prongs projecting from the periphery of said third flange.

14. The drilling catheter assembly as defined in claim 11, said first and second flanges having a plurality of longitudinal grooves along their periphery for receiving a like plurality of prongs projecting from the periphery of said third flange.

15. A drilling catheter assembly comprising: a hollow drilling needle adapted to serve as a catheter affixed to a first flange at its non-drilling end; a second flange adapted at one side thereof to engage said first flange and adapted at its opposite side to engage a rotating shaft; and said first flange with affixed drilling needle and said second flange held together in an assembled position.

16. The drilling catheter assembly as defined in claim 15, said second flange having a dowel projecting from its centre and located inside of, and concentrically with, said hollow drilling needle.

17. The drilling catheter assembly as defined in claim 16, said dowel having a diameter such that it is easily withdrawn from said hollow drilling needle after drilling.

18. The drilling catheter assembly as defined in claim 17, said dowel being sufficiently long to prevent drilling debris from blocking the hollow drilling needle once the dowel has been withdrawn.

19. The drilling catheter assembly as defined in claim 15, said first and second flanges having a longitudinal groove for receiving a prong projecting from a third flange adapted its side opposite said prong to engage a drilling handpiece.

20. The drilling catheter assembly as defined in claim 15, said second flange having a dowel projecting from its centre and located inside of, and concentrically with, said hollow drilling needle.

21. The drilling catheter assembly as defined in claim 16, said dowel having a diameter such that it is easily withdrawn from said hollow drilling needle after drilling.

22. The drilling catheter assembly as defined in claim 17, said dowel being sufficiently long to prevent drilling debris from blocking the hollow drilling needle once the dowel has been withdrawn.

23. The drilling catheter assembly as defined in claim 15, said first and secondflanges having a longitudinal groove for receiving a prong projecting from a third flange adapted its side opposite said prong to engage a drilling handpiece.