ENDODONTIC INSTRUMENT

Abstract

An endodontic instrument comprises three principal parts: a sleeve-shaped housing (1) one end of which is closed with a nut (2) provided with a straight-through hole; a movable bolt (3) situated axially in the housing (1); and a replaceable working nosepiece with a coupling attachment (4) to which, at the other end of the housing (1), permanently joined is a cannula (5) with the diameter of 0.30-0.35 mm inside which two thin wires with the diameter of 0.07-1.5 mm are placed to form a loop (6) outside the cannula (5), said wires being joined permanently with each other outside the attachment (4) with the use of a fastener (7). The housing (1) has, on its side surface and in its portion adjacent to the working nosepiece, a longitudinal slit (8) is provided with a width exceeding slightly the thickness of the wire which, on a portion of its length, has a recess (9) with a size exceeding slightly the size of the fastener (7), and the a movable bolt (3), on its working nosepiece side, has a properly shaped groove (10) with a shape analogous to this of the longitudinal slit (8) in the housing (1), in which there are ends of the wire fastened in a fastener (7). The fastener (7) is further situated in a widened portion of the groove (10) provided in the bolt (3) with a screw (11) screwed into opposite side of the bolt (3) for provisional adjustment of position of the bolt (3) with a knob protruding outside the nut (2) screwed onto end portion of the housing (1), whereas there is a spring (13) between the nut (2) and a seat (12) formed on the bolt (3). Side surface of the housing (1) is provided with a longitudinal recess (14) for a screw (15) used to move the bolt (1) manually and thus to draw the wire loop (6), said screw being screwed into a threaded hole provided in the bolt (3) perpendicularly to its axis.

Claims

1. An endodontic instrument having a sleeve-shaped housing terminated, on one end, with a nut, and on the other end, with a replaceable working nosepiece with a cannula in which a thin wire is situated forming a loop outside the cannula and equipped with a loop tensioner, characterised in that it comprises three principal parts: a sleeve-shaped housing (1) one end of which is closed with a nut (2) provided with a hole; a movable bolt (3) situated in the housing (1) on its axis; and a replaceable working nosepiece with a coupling attachment (4) fixed on properly shaped other end of the housing (1) to which permanently fixed is a cannula (5) with the diameter of 0.30-0.35 mm inside which two thin wires with the diameter of 0.07-1.5 mm are placed forming a loop (6) outside mouth of the cannula (5) and joined with each other with the use of a fastener (7) outside the attachment (4), whereas side surface of the housing (1) is provided, at its working nosepiece end, a longitudinal slit (8) with the width exceeding slightly the thickness of the wire, with a portion of the length of said slit having a recess (9) with a size exceeding slightly the size of the fastener (7), and the a movable bolt (3), on its working nosepiece side, has a properly shaped groove (10) with the shape analogous to this of the longitudinal slit (8) in the housing (1), in which there are ends of the wire fastened in a fastener (7), and the fastener (7) itself is moreover situated in a widened portion of the groove (10) of the bolt (3), with a screw (11) screwed into opposite side of the bolt (3) for provisional adjustment of position of the bolt (3) and with a knob protruding outside the nut (2) screwed onto end portion of the housing (1), whereas there is a spring (13) between the nut (2) and a seat (12) formed on the bolt (3), and moreover, side surface of the housing (1) is provided with a longitudinal recess (14) for a screw (15) used to move the bolt (1) manually and thus to draw the wire loop (6), said screw being screwed into a threaded hole provided in the bolt (3) perpendicularly to its axis.

2. The instrument according to claim 1 characterised in that onto a threat provided in side surface of the housing (1) above the longitudinal recess (14) for the screw (15) used to move manually the bolt (3), a nut (16) is screwed limiting the travel of the bolt (3) upwards.

3. The instrument according to claim 1 characterised in that the wire is made of Nitinol.

4. The instrument according to claim 1 characterised in that the cannula (5) of the replaceable attachment with an option to adapt its shape arbitrarily.

5. The instrument according to claim 1 characterised in that the wire loop (6) is formed outside a hole provided in side surface of the cannula (5), in the vicinity of its blindly closed tip.

6. The instrument according to claim 1 characterised in that the wire loop (6) is formed between two holes provided in side surface of the cannula (5) in the vicinity of its blindly closed tip.

7. The instrument according to claim 1 characterised in that the wire loop (6) is formed between a hole provided in side wall of the cannula (5) in the vicinity of its tip and a hole provided at the end of the cannula (5).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The subject of the invention is illustrated in drawings, of which:

[0008] FIG. 1 shows the endodontic instrument with rectilinear cannula in the axonometric projection;

[0009] FIG. 2 shows the endodontic instrument without its working portion in axial section;

[0010] FIGS. 3-5 show schematic views of the tip of the cannula fixed in the working nosepiece, in consecutive variants of embodiment; and

[0011] FIG. 6 shows the working nosepiece with rectilinear cannula.

DETAILED DESCRIPTION

[0012] The subject of the invention is presented in the following in its example embodiments.

Example 1

[0013] The endodontic instrument comprises three principal parts: a sleeve-shaped housing 1 one end of which is closed with a nut 2 provided with a straight-through hole; a movable bolt 3 situated axially in the housing 1; and a replaceable working nosepiece with a coupling attachment 4, fixed on properly shaped other end of the housing 1, to which permanently joined is a cannula 5 with the diameter of 0.35 mm inside which two thin Nitinol wires with the diameter of 0.15 mm are placed forming a loop 6 outside mouth of the cannula 5 and joined with each other with the use of a fastener 7 outside the attachment 4. Side surface of the housing 1 has, at its working nosepiece end, a longitudinal slit 8 with the width exceeding slightly the thickness of the wire, which on a portion of its length has a recess 9 with a size exceeding slightly the size of the fastener 7, whereas the movable bolt 3 has, on its working nosepiece side, a properly shaped groove 10 with a shape analogous to this of the longitudinal slit 8 in the housing 1. In the groove 10 provided in the bolt 3 there are ends of the wire fastened in a fastener 7, and the fastener 7 itself is moreover situated in a widened portion of the groove 10 made in the bolt 3. On the opposite side, a screw 11 is screwed into the bolt 3 for provisional adjustment of position of the bolt 3 with a knob protruding outside the nut 2 screwed onto end portion of the housing 1, whereas there is a spring 13 between the nut 2 and a seat 12 formed on the bolt 3. Side surface of the housing 1 is provided with a longitudinal recess 14 for a screw 15 used to move the bolt 1 manually and thus to draw the wire loop 6, said screw being screwed into a threaded hole provided in the bolt 3 perpendicularly to its axis. Onto a thread provided on side surface of the housing 1 above the recess 14, a nut 16 is screwed limiting the travel of the bolt 3 upwards.

Example 2

[0014] In a housing 1 with a bolt 3 with structure the same as in Example 1, a working nosepiece with a cannula 5 with the diameter of 0.30 mm is fixed with the use of a coupling attachment 4, whereas a loop 6 of Nitinol wire with the diameter of 0.08 mm formed outside a hole provided in side surface of the cannula 5, in the vicinity of its blindly closed tip.

Example 3

[0015] In a housing 1 with a bolt 3 with structure the same as in Example 1, a working nosepiece with a cannula 5 with the diameter of 0.33 mm is fixed with the use of a coupling attachment 4, whereas a loop 6 of Nitinol wire with the diameter of 0.1 mm situated between two holes provided in side surface of the cannula 5, in the vicinity of its blindly closed tip.

Example 4

[0016] In a housing 1 with a bolt 3 with structure the same as in Example 1, a working nosepiece with a cannula 5 with the diameter of 0.35 mm is fixed with the use of a coupling attachment 4, whereas a loop 6 of Nitinol wire with the diameter of 1.1 mm formed between a hole provided in side surface of the cannula 5 in the vicinity of its tip and a hole provided at the end of the cannula 5.