US3324555A

US3324555A - Test handle for endodontic root canal treatment

Info

Publication number: US3324555A
Application number: US347183A
Authority: US
Inventors: Zdarsky Eduard
Original assignee: Individual
Current assignee: Individual
Priority date: 1963-02-26
Filing date: 1964-02-25
Publication date: 1967-06-13
Anticipated expiration: 1984-06-13
Also published as: CH408280A; DE1280469B

Description

June 13, W67 E. ZDARSKY 3,324,555

TEST HANDLE FOR ENDODONIIC ROOT CANAL TREATMENT Filed Feb. 25, 1964 Fig.1 ma

Claims. ei. 32-57 This invention relates to a device for treating the root canals of teeth.

It is known that root canal instruments such as reamers, files and smooth broaches are to be employed by measuring the depth of their insertion into the root canal. Thus the handle may be provided with a measuring scale. I have found that a fixation of an adjustable instrument in the handle is difficult. By turning the screw for fixation, the instrument blade is often displaced again; furtheron such a fixation does not allow to determine whether the blade is sufiiciently fixed.

It is, therefore, a principal object of this invention to provide a test handle which ensures exact adjustment of the blade in the handle. A further object of the invention is to ensure the adjusted blade to remain at the determined point in order to make a later displacement impossible. Still a further object of the invention is to provide a very simple and handy test handle shape.

To solve this problem the invention provides a test handle on which the blade is longitudinally slidable only within the handle whereby a guide hook of the instrument is transverse-d in a winding path which is turnable in the handle.

In a preferred embodiment of the invention the windin-g path is formed by a screw drive which is turnably located in the cylindrical space within the handle. For turning this screw drive, a turn button is provided on the exposed end of the handle.

For the fixation of the depth of penetration of the blade only a turning of the turn button with its screw drive is necessary, whereby the instrument corresponds to the direction of turns and is fixed at any point, as the guideway of the screw drive is constructed for self-locking.

The accompanying drawing shows embodiments of test handles according to the invention.

There are shown:

FIG. 1, a longitudinal cross section of a first model,

FIG. 2, a top view on FIG. 1,

FIG. 3, a longitudinal cross section through a second model,

FIG. 4, a top view on FIG. 3.

On the test handle according to FIGS. 1 and 2 a cylindrical handle 1 on its outside is serrated at 2 in order to achieve a good grip. Inside a cylindrical space 3 is provided in which an instrument such as a blade 4, is inseited with its shaft 5. The cylindrical handle has a slot 7 which is fully open only on the one side of the handle which is opposite to the instrument blade tip. The width of the slot corresponds to the diameter of the instrument shaft 5 which is bent on the free end to form a guide hook 6. The hook is slidable within the slot and the instrument can be taken entirely out of the handle on the open side of the slot. The projecting end of the hook is numbered 8. Inside of the cylindrical space a screw drive It is turnably mounted. The hook 6 of the instrument 3,324,555 Patented June 13, 1967 fits in the screw drive and is moved upwardly and downwardly according to the turns of the screw drive. In order to achieve a good fixation and guidance of the instrument, the screw drive 10 is constructed such so as to fit tightly around the instrument shaft and to engage with its superposed windings the hook 6. In this way it is possible to guide the instrument without a wobbling movement.

In order to turn the screw drive, its upper end 11 is engaged by a turning button 12 located in a groove 13 of the test handle.

A serrated head 14 of this turning button provides an easy grip. Also the turning button is provided with a slot 15 in order not to handicap insertion and removal of the instruments. Preferably, the screw drive has a round cross section in order to reduce friction and wear between the screw drive surface and instrument shaft. In order to obtain a self-locking effect between both parts, the pitch of the screw drive is accordingly low. The movement of an instrument on the handle 1 can be seen or controlled at the end of the hook. Furthermore, a measuring scale can be provided at the outside of the test handle.

It goes without saying that the screw drive could for example also be made from a square sectional steel. The turning button 12 can be provided with a hole only instead of the serrated head 14 in which a pin or the like tool is inserted for turning of the screw drive.

In the embodiment according to FIGS. 3 and 4, the handle 20 is provided with an outer screw tube 21 which is located turnably in grooves 22 of the handle 20.

In a centric axial borehole 23 of the handle, the instrument shaft 5 is guided whereby also a slot 25 allows of longitudinal movement of the guiding hook 6 respective to the instrument. In this case, the end 8 of this guide hook 6 projects into a screw drive 26 which is located on the inside of the screw tube 22.

In case the screw tube 21 is turned against the handle 20 which may have a serrated ring, then the instrument moves up and down with its shaft 5 Within the slot 25. This slot 25 as well as the screw tube 21 are open on the upper side to allow exchanging of instruments. A measuring scale can be provided on the surface of the instrument shaft itself.

In order to avoid, by turning the test handle, for example, during the insertion in the root canal, a dislocation of the screw tube 21 and the handle part 30 occurs and an adequate safety device can be provided, for example a key, a bolt or a wedge or a turning tube snapping into a polygon rest located on the handle piece.

I claim:

1. A device for treating tooth-root-canals comprising a handle having walls defining a cylindrical cavity and a bottom provided with an aperture, coiling drive means in said cavity, rotary means secured to the top of said handle, the upper end of said coiling drive means excentrically secured to said rotary means for actuation of said drive means, a shaft carrying an instrument mounted for axial displacement in said cavity, said instrument being a small rod-like tool of a size adapted to be inserted in a root canal, the lower end of said shaft projecting through said aperture and the upper end of said shaft being bent and riding on said coiling drive means, and a longitudinal slot in the wall of said handle so as to expose the tip of said shaft to observation from the outside.

2. The device as claimed in claim 1 wherein said upper References Cited end of said shaft projects outwardly through said slot.

3. The device as claimed in claim 1 comprising a cali- UNITED STATES PATENTS bration along said slot. 291,297 1/1884 120-9 4. The device as claimed in claim 1 wherein said coil- 5 2,494,412 1/1950 slmkms 120-9 ing drive means is a rod of round cross section. 311391066 6/1964 Aversa 206-56 5. The device as claimed in claim 1 wherein said rotary means is provided with a radial slot for insertion of the RICHARD GAUDET instrument. I. W. HINEY, Assistant Examiner.

Claims

1. A DEVICE FOR TREATING TOOTH-ROOT-CANALS COMPRISING A HANDLE HAVING WALLS DEFINING A CYLINDRICAL CAVITY AND A BOTTOM PROVIDED WITH AN APERTURE, COILING DRIVE MEANS IN SAID CAVITY, ROTARY MEANS SECURED TO THE TOP OF SAID HANDLE, THE UPPER END OF SAID COILING DRIVE MEANS EXCENTRICALLY SECURED TO SAID ROTARY MEANS FOR ACTUATION OF SAID DRIVE MEANS, A SHAFT CARRYING AN INSTRUMENT MOUNTED FOR AXIAL DISPLACEMENT IN SAID CAVITY, SAID INSTRUMENT BEING A SMALL ROD-LIKE TOOL OF A SIZE ADAPTED TO BE INSERTED IN