SURGICAL INSTRUMENT STERILIZING TRAY

Abstract: A dental or surgical instrument tray which comprises a pair of oppositely disposed upright side walls (1 and 2), a rack (5) extending between the side walls (1 and 2) for locating instruments in mutually spaced apart relationship, a clamping bar (25) hingedly attached to one of the side walls and having means for releasably latching the bar to the opposite side wall, thereby clamping the instruments in place in the rack (5), and a holder (20) for retaining small accessories in a part of the tray away from the instruments, said holder being a snap-fit into the tray.

Description: SURGICAL INSTRUMENT STERILIZING TRAY This invention relates to tray for sterilising and storing dental and surgical instruments, particularly hand instruments. It is highly desirable that dental and surgical instruments should be adequately sterilised between patients. The traditional way of sterilising instruments is to load them into an autoclave and remove them after an adequate sterilisation regime, e.g. about 10 minutes at approximately 120°C. The autoclave is then opened and the instruments removed for further use. According to the traditional system, the instruments are simply loaded loosely into the autoclave. This has the disadvantage that they can damage each other by being knocked together during loading and unloading, or during the sterilisation process, and the dentist may need to search in the autoclave for a particular instrument needed for the next patient. More recently, cassettes have been employed into which the instruments are loaded and the entire cassette placed in the autoclave. One example of such a cassette is described in US Patent No. 5284632. One problem arising from the use of cassettes of the kind described in US Patent No. 5284632 have is that they are of complicated construction and, because of their enclosed nature, it is difficult to identify the instruments which have been loaded in the cassette. Furthermore, there is no provision for sterilising smaller items necessary for routine dental treatment, such as burs, matrix retainers, brushes, cups and drill bits. It is also highly desirable in order to avoid the spread of infection that any receptacle in which dental pastes or filling materials are mixed should also be sterilised. According to one aspect of the present invention there is provided a dental or surgical instrument tray which comprises a pair of oppositely disposed upright side walls, a rack extended between the side walls for locating instruments in mutually spaced, generally parallel relationship, a clamping bar hingedly attached to one of the side walls and having means for releasably latching the bar to the opposite side wall, thereby clamping the instruments in place in the rack and a holder for releasably retaining small accessories in a part of the tray away from the instruments, said holder being a snap-fit into the tray. In one embodiment, the tray will be of open construction having side walls and end walls, and being bridged by one or more instrument receiving racks which are spaced apart lengthwise of the side walls. The holder or holders for retaining the accessories such as burs and brushes are manufactured from a heat-resistant plastics material and have projections which are a snap-fit into opposed upright faces of the tray. Such faces may comprise an end wall and a portion of the rack or a part attached thereto. Similarly, the holder for prophy paste (used for polishing or cleaning teeth) or dental filling materials may also be manufactured so as to be a snap-fit into the dental tray and is provided with projections for this purpose engaging in upright flanges or other opposed surfaces of the tray. Preferred materials include heat-resistant plastics materials and stainless steel, examples of heat-resistant plastics being fluorinated polymers, e.g. P.T.F.E. Typically, the tray has no effective base or cover so that the instruments can be easily seen when held in the tray and identified as such. This enables the instruments to be cleaned ultrasonically while they are contained in the tray. Further identification can be provided by colour code buttons which are removably received in holes, e.g. in one of the side walls of the tray. Such buttons are conveniently coloured buttons made from a heat-resistant rubber, such as silicone rubber. The clamping bar may be spring-biased into an open position so that as the latch is released, the clamping bar springs up and allows easy access to the instruments. In order to retain the instruments individually and firmly supported in the rack, the clamping bar incorporates an elastomeric or rubber clamping strip attached to its underside. Preferably, such rubbery material is a non-foamed material and has a profile including at least one flange which is designed to press onto the instruments. In order to give a visual indication that the instruments in the tray have been adequately sterilised, the tray may include a holder for an indicator strip. Such strips contain a chemical which changes colour after it has been subjected to a heat treatment which would be adequate to sterilise the instruments. Although the preferred sterilisation treatment is by steam or hot air, other sterilising gases and liquids may be employed. In the case of steam, air or nitrogen, a temperature of 110~120°C for .about 10 minutes is usually sufficient to achieve effective sterilisation. Other methods of sterilisation include chemicals (e.g. ethylene oxide), ultraviolet radiation, microwave radiation or radiation from a radio-active source. Further features, aspects and advantages will become apparent from the following detailed description of preferred embodiments, in which:- Figure 1 is a perspective view of a tray in accordance with the invention; Figure 2 is a plan view of the tray shown in Figure 1; Figure 3 is a perspective view of a handle for use in removing a tray from an autoclave; Figure 4 is a section taken on the lines IV-IV in Figure 1 ; Figure 4A is a sectional view of an identification button on an enlarged scale; and Figure 5 is a perspective view of a storage container for storing trays of the kind shown in Figure 1. Referring to the drawings and in particulars Figures 1, 2 and 4, the tray comprises an open framework formed from the pair of side walls 1 and 2 and end walls 3 and 4. Side walls 1 and 2 are bridged by racks 5 and 6, each having a plurality of notches 7 for receiving a variety of dental instruments 8 (see Figure 2). As can be seen best in Figure 1, the side and end walls and the racks have a common base flange 10 and the walls and flange 10 may be manufactured by stamping from a suitable corrosion-resistant sheet metal such as stainless steel. The end walls and side walls are formed by folding at right angles to the flange portion 10. Thus, side walls 1 and 2 and end walls 3 and 4 together with the flanges 10 are typically of an integral construction. Side wall 1 may be formed with a series of apertures 1 1 and 12 to reduce the weight of the tray and to permit adequate access of steam, hot air or other sterilising fluid to the instruments. This open design enables the instruments to be hand cleaned and allows ultrasonic cleaning of the instruments while in the trays. The holes 12 or corresponding holes 13 in the other side wall 2 may be used for receiving coloured identification buttons which can be removably inserted into the holes. A section through a typical button is shown in Figure 4, and such buttons are preferably manufactured from silicone rubber. As shown best in Figures 1 and 2, the tray includes a plastics holder 20, which is provided with a series of holes for retaining burs, brushes prophy cups and the like. In Figure 2, there are two such holders and in Figure 1 there is one holder 20 for burs and the like, and a second holder 21 for mixing prophy paste and other dental paste and filling materials. Because the holders are retained releasably, e.g. by a snap-fit into the tray, they can be exchanged in a given dental tray. In the case of the holder 20, this is typically manufactured as a generally cylindrical or otherwise elongated plastic block, having small projecting portions 22 at each end, which are a snap-fit in corresponding holes in an end wall 3 and in a flange 24 attached to one of the racks 5. The rack includes a slot for a matrix retainer 28 In the case of the holder for prophy paste, a similar projection 22 is formed at each end of the plastic block and this similarly engages in corresponding holes in the end wall 4 and in a flange 24 of the rack 6. The instruments are held in place by a clamping bar 25. This is hingedly attached at 26 to the side wall 1 and has a releasable latch 27 (not shown) at the other end The latch may comprise an inward projection from the clamping bar which engages in a hole in the side wall 2. The clamping bar also incorporates clips 30 for retaining an indicator strip 31. Strip 31 is impregnated with a chemical which changes colour or shade once the instruments have been subjected to an adequate sterilisation cycle. Clamping bar 25 incorporates a rubbery gasket 32 for pressing the instruments firmly into the rack. The profile of the gasket is shown clearly in Figure 4 and is an extrusion of a heat-resistant rubber such as silicone rubber. The extrusion includes at least one flange 33, which deflects when the clamping bar is pressed into contact with the instruments. Figure 3 is a perspective view of a handle 40 for lifting dental trays from the autoclave. At one end, the handle has hook members 41 and 42 which are adapted to engage respectively with the upper lower edges of side wall 2. Figure 4 shows a sectional view of one of the colour identification buttons 13. These have a waisted portion 60 for temporarily holding a button in a hole in the side wall of the tray. Such buttons may also be used as plug in feet locating in holes in the flange 10, thereby protecting the dentist's working surface, and prevent the tray slipping on such a surface. The holes for the feet are located in positions in the flange 10 so as not to impede placement in the storage rack shown in Figure 5 . Figure 5 shows a storage rack in which the trays shown in Figures 1 and 2 may be stored before or after sterilisation. As can be seen, the storage rack is of open construction having two upright side walls 50 and 51, and shelf members 52 formed by cutting and bending portions at right angles to the side walls 50 and 51. The width of the opening between the walls 50 and 51 is designed so that the end walls of the trays 3 and 4 will rest on the shelf members 52 so that the front side wall 2 extends across the front of the racks and the trays can be identified as to their owner or their contents, by the colour coding buttons 13.

Claims: CLAIMS:- 1. A dental or surgical instrument tray which comprises a pair of oppositely disposed upright side walls, a rack extending between the side walls for locating instruments in mutually spaced apart relationship, a clamping bar hingedly attached to one of the side walls and having means for releasably latching the bar to the opposite side wall, thereby clamping the instruments in place in the rack, and a holder for retaining small accessories in a part of the tray away from the instruments, said holder being a snap-fit into the tray. 2. A tray as claimed in claim 1 wherein the tray is open above said rack, whereby the contents of the tray can be visually checked without releasing the clamping bar. 3. A tray as claimed in claim 1 or 2 wherein the opposite side walls are bridged by at least two racks, the racks being spaced apart lengthwise of the side walls. 4. A tray as claimed in any one of the preceding claims wherein said holder is formed from a heat-resistant plastics material having recesses for releasably retaining burs, brushes, caps and the like. 5. A tray as claimed in claim 4 wherein the plastics holder is a snap-fit into a space between an instrument rack (or a part connected thereto) and a cross member connecting said side walls. 6. A tray as claimed in any one of the preceding claims which includes a holder for prophy paste which is a snap-fit into the tray. 7. A tray as claimed in any one of the preceding claims which includes a holder for releasably retaining a strip which undergoes a colour change when the tray and its contents have been subjected to an adequate sterilisation procedure. 8. A tray as claimed in any one of the preceding claims which includes one or more removable colour code buttons for identifying the contents of the tray, which are received in a corresponding aperture in the tray.. 9. A tray as claimed in any one of the preceding claims wherein the clamping bar incorporates a resilient, heat-resistant elastomeric strip which is adapted to press onto the instruments and hold them firmly in place. 10. A tray as claimed in claim 9 in which the elastomeric strip comprises a profile having at least one flange adapted to press onto the instruments. 11. A system for storing dental and surgical instruments which comprises a storage rack having side walls for receiving and supporting a plurality of trays as claimed in any one of the preceding claims. 12. A dental or surgical instrument tray for retaining instruments during sterilisation having a rack for locating said instruments in mutually spaced apart relationship and an indicator strip which is removably retained in clip means on said tray, said indicator strip having the property of changing colour or shade when said instruments have been subjected to an effective sterilisation regime.

Inventors: DAVIES SIMON MAITLAND, DAVIES, SIMON, MAITLAND
Applicants: DENTSPLY RES & DEV, DENTSPLY RESEARCH & DEVELOPMENT CORP.
Application year: 1996
Main classification: A61L2
IPC codes: A61B19, A61C19, A61L2