CA2005514A1

CA2005514A1 - Fluid dispenser

Info

Publication number: CA2005514A1
Application number: CA002005514A
Authority: CA
Inventors: Harold J. Kandler; Phillip Robinson
Original assignee: Harold J. Kandler; Phillip Robinson; Galway Dental Technology Limited
Current assignee: Galway Dental Tech Ltd
Priority date: 1988-12-14
Filing date: 1989-12-14
Publication date: 1990-06-14
Also published as: IE883722L; GB8928280D0; GB2229232A; US5033961A; GB2229232B

Abstract

ABSTRACT

A device for dispensing a treatment fluid (such as chlorhexidine) for the treatment of a dental disorder (such as periodontitis), the device (10) comprising a housing (14) for receiving a reservoir (3) for storing the treatment fluid, dispensing means (17,80-92) for dispensing treatment fluid to the area of the disorder and pump means (30-63) for metering and delivering a predetermined quantity of the fluid from the reservoir (3) to the dispensing means (17,80-92), wherein the dispensing means (17,80-92) comprises a cannula (17) removably connectable to the housing (14) and having an angled distal portion (21) for delivery of the treatment fluid to the area of the disorder, means (80-90) being provided for locating the cannula (17) selectively in two positions such that the distal portion (21) can be directed in two different directions, e.g. at substantially 180° to one another.

Description

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F~VI~ DISPENSBR

~he present lnvention relates to a device for a~spensing fluid for t~e treatment of dental di~ordQr~, and in S particular - tho~gh not limited to - to a device for di~pensing fluid for the treatment of periodontiti5.

Periodontitis i5 a disease which affects the gums of an indi~idual. Bacter~a cauqed by a bu~ld-up of plaque on the teeth att~cks the gum and causes the g~m to be detached from the tooth. AS ~hé gum begins to d-tac~ from the tooth a pocket is formed between the tooth and gum where further bacteria accumulates, thereby progreasively worsening the condition. chemical compositions, generally in liquid form, are provided for the local treatment of periodontitis. A
typi~al Composition is chlorhexidine, which l~ ~old under a number of Trade Mark~, some of which are E~UDRIT., CORSODY~, and PERIDEX.

- 20 To treat this condition and avoid gum trauma, it i~
important that relative~y accurately measured predetermined qu~ntiti~ of the tre~tment compo6ition ar- depo~ited directly in the diseased area, namely in the pocket between the gum and the tooth. The known apparatus for achieving this tends to be relatively complex and cumber~ome and also re~atively e~pen6ive. In general, existing apparatus i5 principally used in hospital~ and denta~ ~ur~eries~
Attempt~ have been ~ade to provide reasonably priced dispensing apparatus for dispenslng a t~eatment composltion which are usable by ehe patient at home, however, such attempt~ so far have failed.

ln general, th~ only dev$ce available at an economical price for home use i~ a conventional syringe. A ~yrinqe, when used intra orally, require~ considerable manual dexterity and it is not po~6ible to dispense the treatment compositlon X~G/t~ JR9 - , . ..
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. , accurately in the diseased pocke~. ln general, periodon~it~s attacks a number of teeth simultaneously, and this therefore requires refilling of the syrin~e after each tooth has been treated, otherwise, it would not be possible to maintain S with any accuracy the quantity of treatment composition dispen~ed to each tooth. secauSe of the 6hape and con~tr~ction of ~ yringe~ it io relatlvely difficult ~and in many cases impossible) to depo~it the t~eatment composition preclsaly at th- di~eased pocket.
There is therefore a n-ed for a device for dispensing a treatment fluid ~or treating a dental di~order, particularly, but not exclusively, for treating periodontitis According to this invention there is provided a device for dispensing a treatment fl~id for the treatment of a dental disorder, the device comprising a housing for receiving a reservoir for storing t~e treatmen~ fluid, dispensing means ~or dispensing treatment fluid to the area of the disorder and pump means for metering and delivering a predetermin~d quantity of the fluid from the reservoir to the dispensing means, wherein the dispensing means eomprises a cannula having an angled distal portion for delivery of the ~5 treatment fluid to the area of the disorder, méans ~eing provided for locatlng the cannula select~vely ln two positions in which the distal portion is directed in two ai~ferent dire~tions ~e.~. at 180 to one another for ~r~at~ent of upper t~oth and lower teeth).
Advantageously the cannula i~ r~movably connectable to the ..ou~ing ~e.g. by a ~uer lock)~

Ln one embodlment of the inventlon, the pump means ls provided by a piston pump and preferably stop means are provided to limit the length of the piston stroke to a ~JG/101--12/89 . _ _ ,:
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predetermined length. Preferably the piston pump is actuable by a tri~ger-like finger-operable lever that ic pivotably mounted on the housing, said stop means being provided by engagement of the lever and th~ hou6ing.

~n another em~odiment of the invention, non-return valve means are provided in an inlet to and in an outlet from a compression chamber of the pump. Preferably, an outlet from the compression chamber of the pUmp i8 provided in a side wall of the compr~sion chamber.

In ~nother embodiment of the invention, an inlet to the compression chamber is provided through the piston, the non-return valve means being provided in thQ inlet in the piston. Advantageously, a tube extends ~rom the plston into ~he reservolr to draw fluid th~rHfrom, the tube belng movable with the piston.

In another embodiment of the invention, the housing ~0 comprises an elongated tubular portion forming the fluid reservoir and a hand grip for the device, a portion of the housing extendin~ upwardlY from the tuhular housing to house the pump. Prefer~bly, a finger operated lever is pivotally mounted on the ho~sing for moving the piston in the piston ~5 p~mp, the t ever ~eing pivotal towards and away ~rom the tubular portion of the hou6ing. Advanta~eously, the lever is movable towards the housing to ~ellver ~luid from the pump and is movable away from the housing to draw fluid into the pi~ton pump. In one embodiment of the invention, the stop mean~ are provided on the lever.

~n another embodiment of the invention, the reservoir is rolea~ably connected to the ~ou~ing.

~5 Preferably an outlet hou~ing, having an outlet bore extending therethrough communiCatlng with the outlet from :
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the compression chamber of the piston pump, ext~nds laterally away from the upper portion of the hou~ing.
Advantage~usly, the non-return valve moans is mounted in the outlet housin~.
Prefera~ly, a ~eb extends from the o~tlet hou~ing to the upper portion of the housing to support pivotally the sa$d lever. Advantageously, the outlet housing terminates in a tapered portion to be recelved in a correspondingly tapered 10 90C~Ct of thc di3pen3in~ mc~ns. Pro~orably~ a fcrrule ie ~otatably mounted on ths end of the o~tlet housing to engaye a receiver o~ a ~u~r loc~ of the Rocket- i ~n another embodiment of the invent~on, a dispens$ng means 1S is provided, the dispensing me~n~ comprising a r~uer loc~ j -socket and a cannula extending therefrom having an outlet at it~ distal end throu~h the s~ de w~ll o~ the cannula.
!

Advantageously~ the device is suitable for the treatment of periodonitits~
' ' i ~he invention will be more clearly understood from the following de~cription of an em~odiment thereof given, by way of example only, with ~e~erence to the accompanylng drawings, in which:
Figure 1 is a perspective view of a device according to the ~nvention fo~ dispensing treatment fluid for the treatment of a dent~l disorder, Flgure 2 ls a perspective view of portion of the devic~ of Flg. t, Figure 3 is a cro6~ sectional vi~w of portion of the uevice of Fig. 1 in one position, F$gurQ 4 ~s a cro~s ~ectional view similar to Fig. 2 of the device in a dif~erent vo~ition, Figure 5 is an exploded per~peotive view of the device of Fig. 1, and , .. ...........
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~igure 6 is a per~pective view of a po~tion of the device ln use.

Figs. 1 to 5 illustrate a device 1 according to the p~esent 5 illv~nti~n for di~pensing a treatment ~luld, in this case chlorhexidin~ for the treatment of periodontltis. The deviee 1 eomprises a main housing ~ for receiving a reservoir 3. The reservoir ~ is formed ~y a tubular housing 4 closed by a lower end cap 5 and having thread~ 6 at $ts upper end to engage correspond~ng threads 7 in a c~p phrt i on 9 of the hou6ing 2. The reservoir 3 may ~e filled from a stock bottle s~pplied by the chlorhexiaine manufacturer or may be a ~maller-~ized tubu~ar container which ~uch manufactuers may supply. Thu~, a full container of l~ chlorhexidine may be ~crewed into the cap portion 9 to Porm the reservoir 3~ A ~ealing ring 10 i8 provided in the cap portion 9 for sealing the ~oint between t~e cap portion 9 and the reservoir 3.

A pump mear.s, in t~is case provided by a piston pump 11 described below, i5 formed in an upp¢r portion 14 of the housing ~. An outlet portion 1.4 of the housing 2 receives a dispensing mean~ ~ompri~ing e- c~nnul~ 17 extending from ~ uer lock socket 18 that is releasably conne¢ted to a ~pigot ?S cap 19 rotatably mounted on the outlet housing lS, as will be d~cribed below, The distal end portion of the cannula 17 i8 directed at an o~tuse angle to the portion extending axially from socket 18. A leve~ Z0 pivotally connected to the housing 2 operates the piston pump 1 1, as will be described below, for delivering a metered quantity of ~hlorhexid~ne from the re~ervoir 3 into t~e dispensing cannula t7. An outlet opening 21 to one side of the di~pensing cannula ad~acent the distal enA ~7 Ai~p~nRe~ the fluid into a diseased poe~et ~3 formed between a tooth 24 and gu~ as lllustrated in ~ig. ~ and described below.
~lhe distal end ~ of the cann~la 17 is clo~ed.

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The piston pump 11 in the upper portion 14 of the housing 2 will now be described. The housing 14 forms a compression chamber 30 within which a pi~ton 31 i8 slidable. ~he piston 31 comprise~ a main piston member 32 having a bore 33 wlthin whic~ is mounted a piston sealing member 34. A ~ealing ring of flexible pl~stios m~teri~l extend~ ~lrcumf~rcntiAlly around t~e sealing memb~r 34 to ~ny~e s~alingly the cylindrical ~ide wall 36 of the compres~ion ~hamber 30. A
spring 38 biases the pi~ton 31 in t~e directlon o~ the arrow A. An inlet 37 to the compre~sion chamber 30 i~
provided through the piston 31, as will be desc~ibed below, and an outlet 39 through the side wall 36 render~ the ComprQ~ion chamber 30 in communicAtion with a bore 4~
extend~n~ t~rough the outlet hou~ing 15. A non-return valve means comprlses a plu~ 43 to engagQ ~ealin~ly the outlet 39 and thereby prevent fluid flowing back into the compre~sion chamber 30 when the piston 31 is moving in the direction of the arrow A, seQ Figs. 3 and 4 .

~he inlet 37 to the compression chamber 30 provided in the piston 31 is formed by an opening 56 in an end bight wall or cap S7 of the main piston member 32. A tube 58 extends downwardly from the end cap 57 into the ~eservoir 3 for draw~n~ flu~d from th~ roservolr. A non-r~t.llrn vAlve means, to prevent fluid returning to the re~ervoir from the ComprQS~ion chamber when the piston iY being ~oved ~n the direction of the arrow B, is provided by a disc 59 which seals the outlet opening 56. ~he disc 59 is a loose fit in a chamber 60 formed by a bore 61 in the en~ cap 57 and closed by an end bight wall or cap 63 of the sealing membe~
34. A pa~r of duct~ 67 ~hrough the end cap 63 deliver fluid from the c~mher ~n i nt.~ A h~re hB through the sealing member 34 into the compression chamber 30. A ~ependlng ~pud 69 extending from the end cap 63 ~f the seallng member 34 prevent~ the disc .~9 seallng the duct~ 67. ~owever, as soon ~s thc presaure of th~ ~luid in the compre~ion ch~mbor 30 KJG/101--12~89 ' ' ' ' ' , ' , ' ' ' ' "

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exceeds the pre~ure of the flu~d in the res~r~ir 3, the dise 59 is biased 4y the fluid pressure into engagement with the end cap S7 to seal the inlet opening 56. When the pre~ure of the fluid in the compraJsion cha~ber 30 drops S below the pre~sure in tho r~ervoir, the di~c Sg unseat~
from the end cap 57 thus permittlng fluid to flow from the reservoir through the lnlet openiny 56 int~ the compress~on chamber 56.

A pivot pin 73 serves to pivotally mount the lever 20 on a web 72 extending between the outlet hou~ing 15 and the upper h~using 14. ~ pair of lugs 74 extend fro~ the lever 20 through slots 76 in the upper housing 14 and en~age the main pi~ton member 32 for movement thereof. Portions 83 of the lug~ 74 en~a~e ends 78 of the ~lot~ 76 to restrict t~avel of the lug in the direotion of the arro~ C. Portlons 83 of the lever's lugs 74 and/or ends 78 of the houslng'~ slots 76 act as ~top means to limit the travel of the piston in the directlon o~ arrow B. A portion 82 of the lever 20 engages the ~pper hou~ing 14 when the lever 20 $s at the other extreme end of its travel, ~ee Fi~. 3~ ~ever portion 82 and/or the upper housing 14 act a~ stop mean~ to limit travel of the piston 31 in the dire~tion of arrow A. ThuS, th~ stroke oP the plston 31 i~ limited in both directions ~5 and accord~ngly each time the lever 20 i~ deprQssed from one extreme po~ition (Fig. 3) to the other extre~e position lFig. 4), a predetermined quantity of fluid is ~etered from the piston pump. Advantageou~ly the components o~ the pump --are dimen~ioned such that the predetermined quantity i~ 1ml.
A hand grip 75 extends from the oap portlon 9 of the housing 2 for gripping the de~lce. ~hus, with the hhnd grip 75 re~ting in the palm of the hand and the finger~ round the : lever 20, the lever 20 can be pivoted in the direet~on of the arro~ C to move the pi~ton in the dire~tion of th~ arrow B. Releas~ng t~e lever 20 permit3 the lever to pivot in the ~JG~101--12/89 . -. : ~

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reverse direction, thereby permitting the piston 31 to move in the directon of the arrow A under the biassing pressure of the spring 3~ . A gu~rd member 77 ~xtend~ from the ~:ap portion 9 for locating the ~and. A shield 79 i8 provided over the upper portion of the hous~ng.
I

The plug 43 - providin~ the non-return valve means in outlet housing lS - ic spring biased into the outlet 39 by a spring 44 . ~he spring 44 ens~age~ a cup m~mb~x 0.6 wh~ ch is l~ou~ed in a bore 48 in the spigot cap 19. Threads 50 in the ~ore 48 en~age corresponding threads 51 on the outlet ho~sing 15 for securing the spigot cap 19 thereto~ A pair of outlets 5~ in the cup member 46 deliver fluid from the bore 42 of the outlet housinq 1S into a ~o~e 54 in the spigot cap 19.
An 0-ring ~eal 55 seal~ the spigot cap 1g to the outlet housing 15.

The mo~nting arran~ement ~or the cannula 17 and so~ket 18 will now be described. A sleeve 80 is rotatably mounted on a spigot 81 of the ~ap 19, a bore B4 of ~tepped diameter extending through the sleeve 80. The smaller diameter bore portion 85 of the ~tepped bore 84 rotatably engages the ~iy~t 81. A Liny ~6 ~xt~n~s Lound the ~pigot 51 ~
diam~ter slightly greater than that o~ the ~ore portion ~5 to reta~n the ~leeve 80 in po~ltion on the spigot 81, the sleeve 18 being engagea over the ring 8G with a ~nap fit action. The larger diameter bore portion 87 o~ the stepped bore 84 is provided with internal threads 89 of la~qe pitch which engage an end plate 90 on the ~uer socket 18. An end portion 91 o~ the ~pigot 81 is tapered at a tuer angle whlch correspond~ to a correspondin~ T.uer taper of a bore ~2 in th~ socket 18. Such ~uer lock arrangements will ~e known to those sk~lled in the art.

However, ~ecause the ~leeve 80 is rotatable on the ~pigot 81, when the ~ocket 18 i9 ~n sealing engag~ment with the , ~00~

:
tapered portion 91 of the spigot ~1, the socket 18 and the cannula 17 can be rotated. This f~cilitates delivering of fluid into different teeth. For example, to dispense fluid into z- dise~ed well of ~ lower tooth~ the csnnulA will bc S oriented in the direction illu~t~ated in Fig~. 3, 4 and 6 ~n whieh the cannula'~ distal portion is directed downwa~dly, while to dispen~e fluid into a diseased well in an ~pper tooth, the cannula, socket and sleeve will be rotated through 180 such that the cannula' B dlstAl portlon i5 directed upwardly.
i A stand 93 for supporting the device 1 when not in use i8 provided with a recess 94 to receive the base end of the re~ervoir 3. Another rece6~ 95 forms a tray for spare or additional dispen~ing cannulae and sockets. ~hese permit different people, e.g. in the same family, to be treated from ~he same reservoir using a d1f~e~ent cannula for each pe~son.

In thi~ particular embodiment of the invention, the reservoir 3 is of plastics material and may be in~ection moulded or blow moulded. Indeed, ~ mentioned abo~e, the device 1 may be used with a standara contalner in which the chlorhexidine i9 sold in place of the reservoir ~. The other eomponents of th~ device 1, wit~ the exception of the cannula 17, ~ocket 18, ~pringQ 38 and 44, and the valve disc : 59 are all of plastics material and most of them are in~ection mouldG~a. Tho annula 17, 80c!~cet 18 and valve di~
59 are of stainless steel and the springs 38 and 44 are of ~pring steel. It will be appre~iated by those s~illed in the art that the components could be mad~ of any other suitable material and, where they are of plastics m~erial, may be produced other than by in~ection moulding.

In use, the reservoir 3 is filled with appropriate treatment fluid, in th~s case chlorhexidine, and is ~ecured to the cap XJG/101~ /89 ,, ' ,', .,. . : . .
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I o portion 9 of the hous~ng 2. Alternatively, a full container - of chlorhexidine may be scre~ed on to the cap portlon 9.
~he cannula 17 and so~ket 18 are 3ecured to the spigot ~1 and sleeve 80. The device is then ready for u~e.
- S
Inltially, the compres~ion chamber 30 is charged by pivotin~
the lever 20 in the direction of the arrow C. ~his moves the piston 31 in the direction of the arrow B thereby expelling air in the compression cham~er 30 throug~ the outlet valve plug 43 in the outlet 39. AQ the piston 3t mhve~ in the d~reetion of tho arrow ~, the valve dis~ 59 clo~es the inlet bore S~. On releasin~ the lever 2~, the plston 31 move~ in the direction of the arrow A under the biassing force of the spring 38. Movement of the pi~ton in th~ dircction o~ th~ arro~ ~ ~a~ee~ the plug ~3 to 0106e t~e outlet 39 and the valve disc S9 to open the inl~t opening 56. As the piston 31 moves in this direction, fluid i~ drawn into the compre~sion chamber 30 from the reservoir 3. The device 1 i~ thus primed for sub~equent u~e~ For this, the cann~la i~ in~erted into the diseased pocket 23 betw-en the tooth 24 and gum 25 (as illustra~ea, for a low~r tooth, in ~ig. 6), and the lev~r ~0 is moved in the direction of the arrow C f~om the one extreme position of Fig. 3 to the other extreme positioQ of ~ig~ 4, th~r~by to c~u~ ~ p~deter~ e~
metered quantity of chlorhexidine to be di~pen6ed through the outlet 39 and on through the opening 21 ln the cannula 17 into the disea~ed pocket 23.

It will be apparent that upon thereafter releasing the lsver the device 1 w~ll be 8gain primed and ready for u~e either at the same self-treatment session on another ~l~ease~ pocXet or at a future self-treat~ent se~slon.

~ n çerta~n ç~es, 1n~t.iA11y t.~ rl~ar all the air from thP
~5 compres~ion chamber 30 and the bo~es in the outlet housing 15, the ~pigot cap 19 and the cannula 17, a number of ' ' ;
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depre~slon~ of the lever 20 in the direction o~ the arrow C
may be required, Since the length of travel of the piston is ~ontrolled by 5 the trA~r~l of th~ l~vkr ~n, e;~ch t.ime th~ lever 20 is depressed from one extremity of its ~troke to the other a predetermlned metered quantity of fluid i8 dispen~ed las a ~inqle llshot") from t~e compression cham~er ~0. ~hu~, on each u~e, a de~ired predetermined quantit~ of chlorhexidine is dispensed into a dise~sed pooket. If ~n any sltuation, the volume of the treatment fluid may need to be in~rea~ed, more than one "shot", for example two or three "shot~", may be readily dlspsnsed into one or more diseased pocket. This would depend on the instructions ~iven by the der,tist, on the strength of the treatment fluid, and of course on the ~xt-nt of the infection.

While a particular ~hApe and con~truct~on of housing has been de~cribed and illustr~ted, any other suitHble shape and 20 conStruction ma~ be used without departing from the ~cope of the invention. Further, it will ~e appreoiated that the ra~Rrvoir n)~y hF~ of ~ny oth~ ~h~e or construction, ana it is not necessary that the housing should be constructed to rece~ve a container in which chlorhexidine i~ sold. It w~ll of cour~e be appreclated that the leve~ 20 can have a dlfferent ehape and ~onstruotion. Further, it will be appreciated that stop meane (to reatrict t~avel of t~e piston) o~her than stop means acting on the lever could be used. For example, it i8 envisaged t~at the pi3ton could be arranged to mov~ b~tween pred~termlned limits ~ormed wlthln the piston hou~ing, for example within the compres6ion chamber. Such stop mean~ could be provided by rings o~
pro~ection~ in the compression chamber. It will also be appreclated that, although preferable, it is noe essential that the inlet to the compression chamber ~hould be provided in the pi~ton. ~he inlQt to the compression chamber could XJ~Jlo1--t2/89 , _~
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alternatively be provided ~n any other sulta~le location, as lndeed could the outlet.

It 18 envi~aged that other suitable arrangements for - S locating the dispensing m-ans of cannula and socket onto the hou~ing could be used. Howevsr, it i~ particularly advantageous that the bent cannula should be rotatably moun~ed on the housing 80 as to facilitate its u~e ~oth for : upper ~.Q~.h And fo~ lower teeth.
` 10 Further, in certaln case~, it is envisaged that other sui~able di~pen~ing means could be used be~ide3 a cannula.

. -~hile the device according to the lnvention has been : 15 deseribed for use in the treatment of periodontitis, it may ~e used for other dental disorders~ ~t will also be appreciated that the device may be used for the dental treatment of humans and an~mal~

The invention is not limited to the exemplary embodiment hereinbefore described which may be ~ried in construction and detail without departing from the scope of the lnvention claimed.

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Claims

1. A device for dispensing a treatment fluid for the treatment of a dental disorder, the device comprising a housing for receiving a reservoir for storing the treatment fluid, dispensing means for dispensing treatment fluid to the area of the disorder and pump means for metering and delivering a predetermined quantity of the fluid from the reservoir to the dispensing means, wherein the dispensing means comprises a cannula having an angled distal portion for delivery of the treatment fluid to the area of the disorder, means being provided for locating the cannula selectively in at least two positions such that the distal portion can be directed in a corresponding number of different directions.

2. A device according to Claim 1, wherein the cannula is rotable to and locatable in any position between two extreme positions that are at substantially 180° to one another.

3. A device according to Claim 1, wherein the cannula is removably connectable to the housing.

4. A device according to Claim 1, wherein the pump means comprises a piston pump, and stop means are provided to limit the length of the piston stroke to a predetermined length.

5. A device according to Claim 4, wherein the piston pump is actuable by a trigger-like finger-operale lever mounted pivotally on the housing, said stop means being provided by abutment of the lever (at zones distal from the lever's pivotal mounting) and the housing.

6. A device according to Claim 5, wherein the said lever is pivotably movable towards and away from an elongated tubular member forming the fluid reservoir.

7. A device according to Claim 6, wherein said reservoir member comprises a portion of the housing.

8. A device according to Claim 6, wherein said reservoir member is releasably connectable to the housing.

9. A device according to Claim 4 wherein:
an inlet to the compression chamber of the pump is provided through the piston;
a non-return inlet valve means is provided in the inlet to control fluid flow therethrough; and a tube, movable with the piston, extends from the inlet into the reservoir to draw treatment fluid therefrom.

10. A device according to Claim 4, wherein:
an outlet from the compression chamber of the pump is provided in a side wall of the compression chamber, the outlet communicates with a bore in a housing outlet portion that extends laterally away from an upper portion of the housing;
a non-return outlet valve means is mounted in the housing outlet portion to control fluid flow therethrough;
and the housing outlet portion terminates in a tapered portion to be received in a correspondingly tapered socket of the dispensing means.

11. A device according to Claim 1 wherein the cannula has an outlet in its side wall adjacent the cannula's distal end.

12. A device according to Claim 1 and for the treatment of periodontitis, the reservoir containing chlorhexidine.