WO1996003934A9

WO1996003934A9 - Applicator for dental material

Info

Publication number: WO1996003934A9
Application number: PCT/US1994/008824
Authority: WO
Filing date: 1994-08-04
Publication date: 1996-03-28

Abstract

For freehand use by a dentist, there is provided a cylinder (6) containing tooth filling material (18) urged out of the cylinder (6) by spring pressure, sometimes augmented by thumb pressure against the end (12) of a piston rod (11) in the cylinder (6). Flow of the material out of the cylinder (6) through a nozzle (19) is under control of a valve (22) located to be readily manipulated between open and closed positions by the same hand of the dentist. Preferably the filling material (18) is in a discrete capsule containing enough filling material for several teeth and easily placed in and removed from the cylinder. The piston rod (11) includes an articulating segment (116) which may be pivoted to lock the rod (11) in a retracted position for ease of assembly, disassembly, and filling of the applicator with dental material.

Description

APPLICATOR FOR DENTAL MATERIAL DESCRIPTION TECHNICAL FIELD The applicator is especially for use by dentists in deriving a pattern for tooth inlays and crowns and for temporarily positioning an initially flowable, ultimately hardenable material in a tooth cavity.

BACKGROUND ART

In various dental situations, it is necessary to provide a cavity filling material. Currently, filling materials of semi-plastic, semi-fluid substances are often utilized. These have the property of hardening in place shortly after they have been appropriately positioned and contoured and exposed to the air. Often such materials are readily available in semi-solid, cylindrical capsule form or in other discrete bodies of initially readily maneuverable and manageable sizes and shapes. A manually operable, balanced valve is in the outlet nozzle on a cylindrical applicator body for dental material, such as described in Cameron U.S. Patent No. 4,993,948, issued February 19, 1991, for an APPLICATOR FOR DENTAL MATERIAL. There are outside grips for manual rotation or axial translation of the valve to block or to permit outflow of the dental material from the nozzle.

DISCLOSURE OF INVENTION

The applicator for dental material of this invention provides a cylinder containing tooth filling material urged out of the cylinder by spring pressure, sometimes augmented by thumb pressure against the end of a piston rod in the cylinder. Flow of the material out of the cylinder through a nozzle is under control of a valve located to be readily manipulated throughout the range between open and closed positions by the same hand of the dentist. Preferably the filling material is in a discrete capsule containing enough filling material for one or a plurality of teeth and easily placed in and removed from the cylinder. The piston rod includes an articulating segment which may be pivoted to lock the rod in a retracted position for ease of assembly, disassembly, and filling of the applicator with dental material.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is an exploded side elevation view of an end cap and articulated actuating rod for the applicator for dental material of this invention; Fig. 2 is a side elevation cross-sectional view of an end cap, spring, and articulated actuating rod, illustrating the actuating rod in its coaxial and extended position;

Fig. 3 is a side elevation cross-sectional view of an end cap, spring, and articulated actuating rod, illustrating the actuating rod in its articulated and retracted position;

Fig. 4 is a side elevation cross-sectional view of the applicator for dental material of this invention in its disassembled state, illustrating the articulation and retraction of the actuating rod, and the insertion of a quantity of filling material into the applicator body; and Fig. 5 is a side elevation cross-sectional view of the applicator for dental material of this invention in its assembled state, illustrating the extension of the actuating rod and the opening of the valve to dispense a quantity of filling material.

BEST MODE FOR CARRYING OUT THE INVENTION To accommodate and employ these cavity filling materials, we preferably provide a circular-cylindrical body 6 or housing having a central axis. At one end, the operator's end, the body 6 is open and is provided with an external fastening 8 such as a bayonet pin or a thread interengageable with a complementerily contoured end cap 9. The end cap serves as a bearing for a slidable actuating rod 11, which includes a joint portion 11a pivotally connecting an articulated segment lib, as by a pin lie. At its outermost, operator's end the rod 11 has a pressure plate 12 or thumb stop. At its other end, the rod 11 has a piston 13. If desired, the piston is provided with a sealing O-ring 14. The piston is abutted by one end of a spring 16, contained in the end cap 9, the other end of the spring abutting the cap 9.

Against the piston 13 as well as the interior end wall 17 is an individual or separate, discrete mass 18 of filling material. The material is appropriate for positioning in the tooth cavity and can initially be a separate, unbounded mass or can be in the form of a defined capsule. The material 18 is sufficiently fluid to be readily discharged through an outlet opening 19 through the end wall 17 of the device. The opening 19 may continue through a nozzle of sufficient size and of appropriate direction for easy and ready maneuverability into any desired position to confront the particular cavity being treated. The nozzle is preferably molded of a yieldable or flexible plastic sufficiently deformable as to be readily snapped into and withdrawn from a receptor socket at the end of the body 6. Different nozzles may easily be used for different patients and are economical enough to be discarded after each patient.

To control flow through the passage 19 and from the nozzle there is provided a rotary valve 22. This is an even, cylindrical body symmetrical about a cross axis and extends from both ends of a cross bore 24 in the body. So that the balanced rotary or plug valve 22 can be appropriately rotated, there is fitted an exterior, manually engageable cross rod or other control knob 26. In one plug rotary position, a bore 27 through the plug valve is placed in alignment with the passage 19. In a position substantially or approximately at right angles thereto, the bore 27 is out of registry with the passage 19 and interrupts or prevents outflow of the plastic material from the capsule 18. The rotated position of the cross rod 26 helps regulate the amount or rate of discharge of the filling material.

In the use of this device, the end cap 9 is removed along with the spring 16 and the plunger 13, so as to leave the interior of the cylinder 6 entirely empty. A capsule 18 or charge of appropriate size, shape and composition of semi-fluid or semi-viscous material is installed. The capsule is preferred, as it is self- contained and individually manipulable. The charge or capsule is dropped into position substantially against the end wall 17. The plug valve 22 remains closed. The actuating rod 11 is retracted past joint 11a so that articulating segment lib may be pivoted to a non-coaxial, even perpendicular position relative to the rod 11. This position places an end, edge, or side of segment lib against the top surface 9a of end cap 9, thereby providing a stop mechanism and preventing the rod from re-extension into body 6. This provides the user with a quick and efficient way to lock the actuating rod in its retracted position for assembly, disassembly, and filling of the applicator. The cap 9 is then reinstalled onto body 6, and the articulating segment lib repivoted to its coaxial position with rod 11, releasing the spring force upon the piston. The initial effect of the spring force is slightly to displace the piston and some of the material of the charge or capsule up to the surface of the closed valve 22.

When the dentist is ready to utilize the charged device, he simply turns the cross rod or control knob 26 through about a quarter turn. He can hold the body 6 and turn the cross rod 26 with one hand. Valve opening aligns the passage 27 with the passage 19 and makes a flow path for the plastic material to advance into and to discharge from the nozzle, without inadvertently bumping the soft tissue of the mouth, which might cause the release of blood or other fluids that would adversely affect the quality of the impression. The dentist can manipulate the structure very easily and simply because he is not required to furnish manual force to eject material from the cylinder to the tooth area. The spring furnishes the ejection force. All the dentist has to do is to guide or position the nozzle 21 by lightly holding the body 6 in position. He can facilely maneuver the barrel or body 6 into whatever attitude he desires. The spring 16 continues to expel the material until the dentist is finished. Thereupon, he again moves the cross rod 26 and rotates the balanced valve 22 into its shutoff position, thus interrupting the discharge of the plastic material.

While normally the pressure plate 12 need not be contacted during discharge of the plastic material, thumb pressure on the plate 12 can readily augment the spring force. The plate 12 also helps to recompress or recock the spring 16 just before the user reattaches the collar 9 with the bayonet or threaded connection to a refilled cylinder 6 or barrel.

The amount of material in the capsule 18 can be more than is necessary for use with a single cavity. The dentist, by opening and closing the valve 22 from time to time, can release and position different regulated amounts of the plastic material in different locations in the patient's teeth. The device can easily be sterilized between uses on a succession of patients. When the capsule 18 is substantially or fully used, any remaining position of filling material can be expelled to waste by pressure upon the plate 12. This causes the rod 11 and piston 13 to eject forcibly any remains of the material. The structure can then be completely disassembled, sterilized, recharged, reassembled and reused.

Claims

CLAIMS What is claimed as invention is:

1. An applicator for dental material comprising: a. a cylindrical body adapted to receive a semi-fluid charge; b. a nozzle on one end of said cylindrical body and communicating therewith; c. a piston plunger reciprocable in said cylindrical body for displacing said charge from said cylindrical body to flow through said nozzle; d. a spring; e. an articulating actuating rod means for mounting said spring in said body for engagement with said piston plunger; f. a removable cap mounted on the other end of said body and engageable with said articulating actuating rod and said spring for holding said articulating actuating rod and said spring in an initially retracted state when said actuating rod is articulated, and releasing said articulating actuating rod and said spring when said actuating rod is non-articulated, to displace said piston plunger toward said nozzle; g. a flow controlling valve in said body between said piston plunger and said nozzle and movable between one position allowing said flow and another position blocking said flow; and, h. means connected to said valve and disposed outside said nozzle in position to be operated by a person holding said cylindrical body for moving said valve between said one position and said other position.

2. A device as in claim 1 in which said valve is a rotary plug valve.

3. A device as in claim 1 in which said cylindrical body has a body axis and said valve includes a plug shiftable between an open position and a closed position by the same hand of a person holding said cylindrical body at a location axially adjacent to said valve and separated from said nozzle by said valve.