INJECTION SYRINGE DEUCE
Patent ApPIicativ?? by Dr. Russell Sullman) BACKGROUND
Many people are scared of the dentist because of their fear of needles and fear of dental infiltration. As a result of this fear' people in need of dental care may leave treatment until it becomes too late to save their teeth, suffering acute pain through lack of treatment. The device described below is designed to reduce the discomfort and anxiety of those requiring dental treatment by virtue of its mode of action physically and visually.
DESCRIPTION
The Injection Syringe lI)evice (hereinafter referred to as 'the device') consists of a protective cover for all or part of the syringe, a means by which it might be reversibly secured to all or part of the syringe, and a, mechanism that allows the cover to move in relation to the rest of the syringe such that the needle can be exposed when necessary. The cover contains a part through which the needle may be deployed.
That part of the cover in the area where the needle is exposed is shaped so as to maximise the contact between cover and dental gum. This allows pressure and stretching of the gums so that the insertion of the needle into the gums is wholly or partially masked, reducing the pain of injection. The presence of the cover also hides the needle or even the whole syringe, thus lessening anxiety in a nervous patient who sees the injection syringe when fitted with the device.
Existing components of an infiltration syringe may be designed to incorporate the device as an integral part, e.g. a disposable dental needle hub may be provided with the device integrally incorporated into its design, or it might be provided with a system by which the device might be directly attached to the needle hub.
Where not provided for already, optional further mechanisms can be used to control degree of needle exposure.
Needle exposure can be protected against by locking/release mechanisms or elastic/deformable material use. The device can also be used for needle disposal.
All or part of the device, including the needle cover element, may be rigid and/or distortable. Where distortable, firm pressure will cause shape change of the cover such that a wider surface area of An will be stimulated, further masking the needle penetration. The device may be provided in a disposable or re-usable form. The device is designed for use with existing styles of syringe, especially those for dental infiltration, but they may be incorporated into new styles of syringe.
The main mode of action of the device is the exertion of pressure on the tissues to be injected, this pressure stretching the tissues, thereby wholly or partially masking the insertion of the needle into the tissues for infiltration, which occurs as the cover
element moves as a result of the back pressure from the tissues. The device may also be provided so that movement of the cover can be controlled by the clinician/operator.
EXAMPLES
Examples of the device will now be illustrated by reference to the accompanying cross-sectional drawings in which: Figure la shows an example of the device where the device is screwed onto the disposable dental needle hub.
Figure lb shows the device in la during functional use.
Figure 2a shows an example of the device where it is designed to fit directly over the main body of a syringe.
Figure 2b shows the device illustrated by figure 2a in functional use.
Figure la shows an example of the device I) where it is screwed onto the hub H of a disposable dental needle N. the cover C protects and covers the needle. Spring S allows vertical movement of the cover C. Figure lb shows the device illustrated in la during functional use. When placed against gingival mucosa (dental gum surface membrane) M, the resistance offered by M displaces cover C by means of compressing the spring S. such that N may become exposed and allow tissue infiltration. Degree of displacement of C offered by controls the amount of needle uncovered.
Once removed (not shown) from M, the cover C springs back along the axis of the syringe K to protect and cover the needle N once more.
Figure 2a shows a device that is designed to fit over the barrel B and handles L of syringe F. there is a spring G contained within the device.
In figure 2b, when pressure is placed by the practitioners' hand upon handles L and plunger P (as shown by arrows marked X), the syringe is pushed into the device, depressing platform J and spring G. so that needle is pushed through opening O in the cover H. allowing anaesthetic placement. When pressure is removed from plunger P. the needle automatically retracts back under and inside the cover H. dimensions of spring G determine extent of needle exposure.
In all of the above drawings, there is more than one spring present, but the same devices may be operable with the provision of a single spring, e. g. in the case of use of a spring which has a diameter greater than the diameter of the widest part of the syringe, thereby allowing the syringe to be passed inside the diameter of the spring.
The device may be provided with a means of locking (whether reversible or irreversible) that prevents movement of the needle or syringe cover element until necess -. A means of delivering metered or measuredAimited doses may also be incorporated.
A reasonable opening may be provided within the needlelsyringe cover to allow movement of the needle through it. This may be covered with a selfsealing membrane or other means by which the opening is kept closed when not in use.
The device may be equipped with a power supply to allow automatic dispensation.
The device may use a number of methods (e.g. screw-on, clamps, etc) by which it might be reversibly attached to the syringe or some part of it, or it may be operable without being secured to all or part of the syringe.
Existing dental syringes comprise an autoclavable metal frame into which is fitted the disposable dental needle and disposable anaesthetic cartridge. The device may be provided in a form into which these disposable components might be fitted without the need for using the metal frame. This modification of the device may be extended to cover nondental injections.
As previously stated, the device may be disposable or re-usable, and cover all or only part of the anaesthetic syringe. It might also be provided in a form in which the needle and/or anaesthetic cartridge are incorporated as integral part(s) of the device.
The device may be made from plastic, metal, glass, or a combination of more than one of these and/or other suitable materials.