Abstract:
A dental vacuum system having a foot-actuated valve for controlling the flow of vacuum through the system. The foot-actuated valve is located away from the field of operation such that the valve is not exposed to the typical sources of pathogenic contaminants in a dental office.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     (Not Applicable) 
     FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     (Not Applicable) 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to dental vacuum systems and, more particularly, is directed to a dental vacuum system with a foot-actuated pedal vacuum valve that is used to control the vacuum flow to various handheld dental instruments such that the valve is located away from the patient&#39;s proximity to decrease the risk of the transmission of pathogenic contaminants between patients and between patients and the dental office staff. 
     2. Description of the Background of the Invention 
     In the typical dental office, blood, saliva and particulates are not confined to the area inside the patient&#39;s mouth during dental procedures and operations. Blood and saliva have a tendency to spray and splatter during certain dental procedures. Blood, saliva and particulates often collect on dental instruments and surfaces in proximity to the patient&#39;s mouth, including the handheld instruments that are used during the dental procedure. The blood and saliva of patients can carry pathogenic contaminants which may cause infectious diseases such as the common cold, pneumonia, tuberculosis, herpes, hepatitis B, and acquired immune deficiency syndrome (AIDS). Such contaminants place other patients and dental workers at risk of contracting infectious diseases. The United States Centers for Disease Control has issued universal precautions that should be followed by all health care professionals while performing dental procedures and operations. According to the precautions, all human blood and saliva should be treated as if they are known to be infected with the HIV virus, hepatitis B, or some other bloodborne pathogen. 
     FIG. 1 shows a typical HVE device (1). HVE valve body (2) is connected by means of tubing connector base (3) to HVE tubing (4). The vacuum flow through the HVE device is controlled by means of HVE valve control (5). The HVE valve control (5) is typically a rotary or lever type control mechanism. HVE tip (6), which can either be a metal aspirator tip or a flexible plastic evacuator tip, is attached to the HVE valve body (2) and is typically placed in the patient&#39;s mouth to evacuate saliva, blood, and other particulates, such as tooth fragments, that are present during a dental procedure. 
     In the typical dental office, a dental vacuum system, as depicted in FIG. 2 as (7), which includes a high volume evacuator (HVE), a saliva ejector (SE), or both, is used to evacuate blood, saliva and particulates from the patient&#39;s mouth during a dental procedure. As shown in FIG. 2, the HVE device (1) of FIG. 1 is part of the dental vacuum system (7). Central vacuum unit (8) provides the vacuum required for evacuation of the system. Hose (9) is connected between the central vacuum unit (8) and vacuum collection canister (10). The vacuum collection canister (10) is used as a junction for the vacuum system and also typically contains a filter for filtering particulates from the vacuum system. The HVE tubing (4), which has the HVE device (1) connected to it, is in turn connected to the vacuum collection canister (10). It is understood by those skilled in the art that the dental vacuum system (7) of FIG. 2 could also contain a saliva ejector device in addition to or in place of the HVE device as shown. 
     During dental procedures, the outside surfaces of all dental handpieces that are used during the procedure become contaminated. This includes handpieces, such as the HVE device (1), because the device is used in close proximity to the patient&#39;s mouth. As can be seen from FIG. 1, the HVE valve control (5) is used in close proximity to the patient&#39;s mouth, and as such has a tendency to become contaminated with fluids that are expelled from the patient&#39;s mouth. The HVE valve control (5) has moving parts that are particularly susceptible to the collection of contaminants, especially contaminants that are evacuated through the HVE valve inside the HVE valve body (2). The accumulation of such contaminants poses a risk of exposing patients and dental workers to pathogenic contaminants. Also, the HVE valve control (5) is operated manually by health care workers during the dental procedure and thus the outside of the HVE device (1) is susceptible to the accumulation of any possible contaminants that are on the valve operator&#39;s hands. 
     Because the HVE device (1) comes into contact with the patient&#39;s tissue and is in close proximity to the performance of the dental procedure, the HVE device (1) must undergo sterilization and disinfection, or asepsis. In particular, the HVE device (1) must be sterilized after each use. Sterilization methods include steam sterilization using an autoclave, dry heat sterilization, and chemical vapor sterilization. The HVE valve body (2) must be disassembled for proper cleaning and sterilization. 
     Thus, there is a need for a dental vacuum system that provides protection against pathogenic contaminants while isolating moving parts from infectious debris and contaminants. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention, there is provided a dental vacuum system which has a foot-actuated valve that is located away from the proximity of the dental procedure. The vacuum system comprises a vacuum collection canister and a hose. Interposed between the hose and the vacuum collection canister is a foot-actuated valve which is used to control the flow of vacuum to the device. The vacuum system may include a foot-actuated valve that controls just an HVE device, just an SE device, or both an SE and an HVE device. The HVE or SE devices may have disposable covers which cover the tubing connector bases. There is also provided a method for locating the foot-actuated valve in which the valve is connected to at least two sections of hose such that the valve is located away from the field of operation. 
     It is an object of the present invention to provide a dental vacuum system with a foot-actuated valve that is located away from the field of operation such that operation of the valve does not promote the transmission of pathogenic contaminants. It is another object of the present invention to provide a dental vacuum system with a foot-actuated valve that is located away from the field of operation to prevent the accumulation of particulates in and on the valve assembly. It is also an object of the present invention to provide a dental vacuum system with a foot actuated valve that has a one piece disposable HVE or SE and barrier device which covers in an extended position, a portion of the tubing connector bases of the HVE and SE barrier devices. It is yet another object of the present invention to provide a method of locating a foot-actuated valve in such a position as to be located away from the field of operation. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the accompanying drawings, there is shown preferred embodiments of the invention wherein like reference numerals are employed to designate like parts and wherein: 
     FIG. 1 is a view of a typical HVE device; 
     FIG. 2 is a view of a typical dental vacuum system; 
     FIG. 3 is a view of a preferred embodiment of the present invention with a foot-actuated valve; 
     FIG. 4 is a view of a preferred embodiment of the present invention incorporating a dual foot-actuated valve; 
     FIG. 5 is a view of a preferred embodiment of the foot-actuated valve of FIG. 3; 
     FIG. 6 is a view of a preferred embodiment of the dual foot-actuated valve of FIG. 4; 
     FIG. 7 is a view of a disposable one piece HVE and barrier device in the unextended position; and 
     FIG. 8 is a view of a disposable one piece HVE and barrier device in the extended position. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the figures for the purposes of illustrating a present preferred embodiment of the invention only and not for purposes of limiting the same, the figures show a dental vacuum system with a foot-actuated valve which is located outside the proximity of the field of operation. The skilled artisan will readily appreciate, however, that the subject invention can be constructed with the foot-actuated valve located in various positions in order to achieve the same result. 
     More particularly and with reference to FIG. 3, there is shown a preferred dental vacuum system, generally designated as (11), that preferably comprises a foot-actuated valve (12) located between the HVE device (1) and the vacuum collection canister (10). The foot-actuated valve (12) is attached to the HVE tubing (4) and may be positioned anywhere on the HVE tubing (4) as is practical. The foot-actuated valve (12) includes foot-actuated valve control (13) which allows for the adjustment of vacuum flow to the HVE device (1). Thus, the HVE device (1) may include a valve and valve control, but they are not necessary and would be redundant if present. 
     Turning to FIG. 4, a preferred embodiment of the present invention as designated generally as (14) is shown which incorporates SE device (15). The SE device (15) comprises SE tubing connector base (16), SE valve body (17), and SE tip (18). Dual foot-actuated valve (19) is connected to SE tubing (20) and to the HVE tubing (4) between the HVE device (1) and the SE device (15) and the vacuum collection canister (10). In a preferred embodiment, the dual foot-actuated valve (19) comprises separate control mechanisms (21, 22) to independently control the vacuum flow to the SE device (15) and the HVE device (1). 
     FIG. 5 shows a preferred embodiment of the foot-actuated valve (12) of FIG. 3. The foot-actuated valve (12) is constructed as a rotary slide valve in a preferred embodiment. The foot-actuated valve control (13) is a rotating threaded cylinder located in housing (23) and engages internal threaded cylinder (24). Rotation of the foot-actuated valve control (13) causes rotation of the internal threaded cylinder (24). Internal threaded cylinder (24) has a toothed portion (26&#39;). Rack (25) has a plurality of teeth (26) which engage the teeth (26&#39;) of threaded cylinder (24). Valve plug (27) is attached to one end of the rack (25). Rotation of the internal threaded cylinder (24) causes the rack (25) to move perpendicularly to the internal threaded cylinder (24) and thus causes the valve plug (27) to move in or out of air flow channel (28) to restrict or permit vacuum flow to the HVE device (1), which is connected to one of a plurality of tubing connectors (29). It can be understood by those skilled in the art that the foot-actuated valve (12) may be constructed such that the valve provides variable vacuum operation or may be constructed as an on/off switch. The foot-actuated valve (12) may be of any type suitable, one such type being a pedal vacuum valve. Also, the foot-actuated valve (12) may be constructed using any valve arrangement that is commonly accepted in the art, such as a rotary stem valve or other combinations of levers involving gear movements to control stem valves. 
     FIG. 6 shows a preferred embodiment of the dual foot-actuated valve (19). The dual foot-actuated valve (19) is constructed as a dual rotary slide valve in a preferred embodiment. Foot-actuated control mechanisms (21, 22) are rotating threaded cylinders located in housing (30) and the control mechanisms (21, 22) are operated independently to engage internal threaded cylinders (31, 32). Rotation of the control mechanisms (21, 22) causes rotation of the internal threaded cylinders (31, 32). Racks (33,34) each have a plurality of teeth (35, 36) which engage teeth (35&#39;, 36&#39;) carried by threaded cylinders (31, 32), respectively. Valve plugs (37, 38) are attached to one end of each of the racks (33, 34). Rotation of the internal threaded cylinders (31, 32) causes the racks (33, 34) to move perpendicularly to the internal threaded cylinders (31, 32) and thus causes the valve plugs (37, 38) to move in or out of air flow channels (39, 40) to restrict or permit vacuum flow to the HVE device (1), which is connected to one of a plurality of tubing connectors (41), and to restrict or permit vacuum flow to the SE device (15), which is connected to one of a plurality of tubing connectors (42). It can be understood by those skilled in the art that the dual foot-actuated valve (19) may provide variable vacuum operation using the control mechanisms (21, 22) or may be constructed as an on/off switch. The dual foot-actuated valve (19) may be of any type suitable, one such type being a dual pedal vacuum valve. The dual foot-actuated valve (19) may be constructed using any valve arrangement that is commonly accepted in the art, such as a rotary stem valve or other combinations of levers involving gear movements to control stem valves. 
     FIG. 7 shows the HVE device (1), the tubing connector base (3), and the HVE tubing (4). An accordian-like barrier sleeve (50) is shown attached to the HVE tip (6) by connector ring (51) in an unextended position. The connector ring (51) may be rigidly attached to the HVE tip (6) to form a unitary disposable device or may be slidably attached to a reusable or disposable HVE tip (6). The barrier sleeve (50) may be constructed of any type of flexible material, such as plastic, that is impenetrable to fluids and liquids. The sleeve (50) is shown in an extended position in FIG. 8. The sleeve (50) covers the tubing connector base (3) and a portion of the HVE tubing (4) to prevent the transmission of pathogenic contaminants. 
     The sleeve (50) can be used with conventional HVE or SE devices that have conventional valves and valve bodies. The sleeve (50) may also be used with HVE or SE devices that do not have conventional valves and valve bodies but are instead controlled by a pedal vacuum valve. The sleeve (50) may be provided with a ring, tab, or other device at one end to facilitate movement from the unextended position of FIG. 7 to the extended position of FIG. 8. 
     The present invention provides solutions to the problem of pathogenic contaminants collecting on dental handpieces that are present with such devices that are in use today. It will be understood, however, that various changes in the details, materials, and arrangements of parts which have been herein described and illustrated to explain the nature of the invention may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims.