EQUIPMENT FOR ENCLOSING OF TOOTH DURING DENTAL TREATMENT

Abstract: A chamber for isolation of the working site during dental treatment the chamber including an upper part (1) with a groove (11) and a lower part (2) with a locking ring (12) and tongue (13) to interlock each other. The upper part (1) and the lower part (2) can be coupled together and, while interlocked with each other, can be moved relative to each other and be uncoupled from each other.

Description: Equipment for enclosing of tooth during dental treatment The invention relates to a device which is to be used for the enclosing of a tooth inside the oral cavity during treatment thereof. More particularly the invention relates to a chamber which can be arranged over a tooth where there amalgam or another filling material in a tooth shall be removed, and where drilling and the use of instruments takes place through openings of the chamber. In connection with the dental treatment of human beings amalgam and hardenable plastic materials are used as filling material for teeth which are damaged or affected by dental caries. The affected part of the tooth will be removed mechanically by drilling out and/or by scraping. Thereafter amalgam or hardenable plastic material will be used as filling mass for the prepared hole. Amalgam is an alloy which among other things contains mercury. In an unfixed state it is highly toxic even in small doses. As a constituent of amalgam mercury is not considered to be toxic, however there is some uncertainty to which extent free mercury is sorted out from an amalgam filling. Because of the uncertainty about this one wishes to shield both patient and dentist against being exposed to possibly unfixed mercury of the amalgam during dental treatment. Some of these exposures are due to amalgam particles falling outside the tooth during drilling out of old fillings for instance, but also due to vapour and dust produced by the use of high-speed drills. Also during insertion of new amalgam such an exposure can occur. Furthermore many hardenable plastic materials now in use have been proven cause allergies among dentists and other personnel insolved with inserting and removing of fillings of such materials. The quality of the fillings which are being inserted into the teeth, their resistance and life, depend on the area near the teeth and the teeth themselves being dry during filling of the holes. This is difficult to achieve because of salivation and a moist environment in the oral cavity. In the course of the dentist's work in the oral cavity a mirror will be used to be able to have a look into places of difficult access. The surface of the mirror often becomes covered with water and other things which must be dried many times during treatment. Some methods are known which prevent the patient and dentist coming into contact with amalgam and hardenable plastic materials during dental treatment. One of these methods is placing a sucking device in the oral cavity which is driven by water, a saliva ejector which removes saliva. Additionally a vacuum device is used which removes amalgam debris and water. Such equipment is not entirely satisfactory as the amalgam debris can be spread over the entire oral cavity, and the ejector is fairly effective only in its close proximity. This implies that the saliva ejector must be positioned close to the treatment site. Neither the saliva ejector nor the vacuum device will remove mercury vapour to the extent desired and will not be able to prevent amalgam particles from coming into contact with soft tissue of the oral cavity before being sucked off or swallowed. A number of dentists also use a further method for preventing at least direct contact of the amalgam and the oral cavity. A piece of elastic, rubber-like cloth will be pulled over the tooth after a suitable orifice has been cut into it. The cloth is pressed down to the treatment site and tightens around it. The cloth will be strechted out of the oral cavity and a frame will be arranged around its edges outside the patient's mouth in such a manner, that it is possible for the patient to breathe between the lips and the cloth. The cloth takes on the shape of a funnel the inside of it fitting to the tooth. In this way a shield around the tooth is obtained where fluid and amalgam particles can be collected and removed by a sucking device. This is a somewhat better solution than the method mentioned above, but it results in a difficult working environment for the dentist. This method does not serve to collect any possible mercury vapour. Recently dentists have, in addition to a vacuum device sucking from the oral cavity, started using a precision sucking device placed in front of the patient's face. Additionally a fresh-air mask is used to avoid the patient inhaling mercury vapour. None of the described methods represents an effective collecting of amalgam particles and -vapour such that the patient or the dentist is sufficiently shielded from possible exposure to mercury. Furthermore the dentist will also not, to a desireable extent, achieve a clean mirror. The requirement to keep the treatment position dry long enough to effect a filling is also not sufficiently addressed. A device consisting of a U-shaped protection which is put over the tooth or the teeth to be treated is described in US patent 4.611.992. In one of the free side edges of the U is provided a hole, through which intruments can be introduced near to the position of the tooth which is to be treated. The device is fastened to the instrument. This solution is provided to avoid air, watei and particles being spread around in the oral cavity. These devices only avoid amalgam particles, vapour and dust being splashed against the oral cavity or the dentist during drilling and rinsing operations. The device is not effective in amalgam coming into contact with the gums or being swallowed during drilling. To to some extent a corresponding solution is described in US patent nr. 4.424.036. This solution avoids direct splashing in all directions, but falls down around the treatment position and comes into contact with the gum. In US patent 4.917.603 is described a solution consisting of a system with a partly closed chamber around the treatment position. A frame is put down over the gums around the treatment site. Onto this frame is put an instrument head, to which a drill, a sucking instrument, air supply and a fibre-optic is fastened for supplying of light and for transmitting pictures which show what is taking place at the treatment position. Since the instrument head has many instruments fastened to it one cannot see past it and therefore transition to an outer screen is used. This is rather expensive and partly difficult to use. It also does not provide a good working situation to the dentist. Whenever the drill needs to be changed the instrument head has to be coupled to the frame consequently, there is no longer a closed chamber around the treatment site, and patient and dentist will be exposed to residues, vapour and particles of amalgam. In the NO- 178.093 is described a bubble-like device which can be put over one or more teeth so they are enclosed for executing of dental treatment operations. The instruments can be introduced through a suitable opening for removing particles, vapour and residues from the treatment in a controlled manner without reaching the oral cavity. When the work in connection with cleaning of the drilled hole is executed the bubble is divided into two parts by pulling of a tear-off strip so that only the lower part remains and forms a protection against the introduction of saliva and fluid into the tooth hole when this is to be tightened. Since upper and lower part are separated from each other it is impossible to reverse the process by putting them together again. In the case of the NO-178.093 the instrument's opening in the upper part is provided at a fixed place, something which can cause unsuitable working conditions if all sides of a tooth need to be reached. The aim of the invention is to create chamber around the teeth consisting of an upper part and a lower part which can be uncoupled and thereafter coupled together again and furthermore can be moved relative to each other. This is obtained by arranging the upper part and the lower part to each other over a reversible snap-coupling, whereby the upper part and the lower part can be moved more than one turn relative to each other. Further details of the invention can be learned from the following description and drawings of an example of an embodiment of the invention. Figure 1 shows a perspective view of a device according to the invention. Figure 2a shows a cross section of the bubble, and 2b shows details of the coupling between the upper part 1 and the lower part 2. Figure 3a and b show two different views/cross sections in relation to Figure 2. The device has the form of a bubble which is formed of an upper part 1 and a lower part 2. These are coupled together by a snap-coupling which allows the upper part 1 and the lower part 2 to be turned relative to each other. In the upper part 1 an instrument opening 3 is provided. Through the instrument opening 3 it is possible to reach into the device 1 , 2 with a drill and other tools for dental treatment. The upper part 1 is produced from a somewhat elastic, transparent plastic material, while the lower part 2 is made of a somewhat harder, transparent plastic material. The upper part 1 can be produced in such a way that it has a magnifying effect if one lookes through it. The dentist can then better see and execute the work in smaller holes as well as in larger ones in the tooth. A large extent of the upper part 1 is formed thin so that it is possible to look through it to the treatment site inside the bubble. This is a flexible window 4 which can be slightly be dented if during treatment the dentist wants to have a look at different parts of the treatment site or if he has to turn the working instrument. In the vicinity of the window the instrument opening 3 is located. The hemispherical lower part 2 is provided with two openings, a longitudinal tooth opening 6 and circular opening 7 arranged to the side of the tooth opening 6. The opening 7 is coupled to the dentist's vacuum device, so that the entire area inside the bubble is maintained free of particles, vapour and large filling residues. The tooth opening 6 has a somewhat unsymmetrical shape according to the cross section shown in Figure 2a. When the bubble is used to create a closed chamber around a tooth the bubble is be set down over the tooth whereby the tooth opening 6 is drawn over the tooth. The outer part of the tooth opening 6 clings to the gum around the tooth. A first flap 8 covers the gum from the outer side of the toot! and a second flap 9 covers the im er side of the tooth underneath the tongue. A smaller set of third flaps 10 cover the gum between the teeth or directly against the neighbouring tooth. As mentioned above the upper part 1 and the lower part 2 are coupled together over a snap-coupling the cross section of which is circular. At the outer periphery along the circular form of the upper part 1 is located a track, a groove 11. At the outer side of the circular form of the lower part 2 is located an -shaped locking ring 12 which is fastened to the lower part. The long arm of the L-shape clings to the lower part 2 and the short arm of the L-shape forms a tongue 13 which corresponds to the inner track 11. The upper part 1 and the lower part 2 are made from flexible plastic material and the locking ring 12 from a somewhat harder plastic material. When the upper part 1 and the lower part 2 are set together so that the groove 11 fits together with the tongue 13 these parts snap together and form a lock. When the upper part 1 and the lower part 2 interlock each other they can be turned relative to each other one or more turns in a plane entending through the circular area of the coupling. The upper part 1 and the lower part 2 can easily be separated form each other. Through the instrument opening 3 the dentist can gain access with instruments such as a drill and other tools / instruments. The device is transparent and the mirror can be used from the outside and willl not get soiled. When the dentist has completed his work at the treatment site and begins filling the hole, the upper part 1 can be separated from the lower part 2 by pressing together a little the upper part 1 and the interlocking between the parts loosens. The tongue 13 and the groove 11 let the interlocking release and the parts can be separated from one another. Since the parts 1 , 2 can be moved relative to each other the device in hand can be used for all teeth in the upper and lower jaw, and the dentist will be able to execute tooth treatment in a practical way. The solution in hand results in better ergonomics for the dentist since less aids are necessary inside the oral cavity during treatment compared with known arrangements. With this method also a better environment and less contamination in the dentist surgery is obtained. Also it is avoided that the patients swallow amalgam residues which then are conducted into the sewer network. Further one does not need a precision sucking device or fresh air mask. During dental treatment the invention allows to avoid amalgam soil on the bottom which would be lead to the drain while wiping up.

Claims: Patent claims 1. Chamber for isolation of the working site during dental treatment the chamber including an opening (7) for a sucking device, an instrument opening (3), a tooth opening (6), and formed by an upper part (1) arranged to a lower part (2), characterized in that the upper part (1) and the lower part (2) are arranged to each other by a reversible snap coupling, whereby the upper part (1) and the lower part (2) can be moved more than one turn relative to each other. 2. Chamber for isolation of the working site during dental treatment according to the preceding claim, characterized in that the upper part (1) is provided with a window (4) which is flexible. 3. Chamber for isolation of the working during dental treatment according to claim 1, characterized by flaps (8, 9, 10) for flushing against the gum.

Inventors: BORCH BJOERN, NILSSON JOHN THORLEIF, BORCH, BJOERN, NILSSON, JOHN, THORLEIF
Applicants: BORCH BJOERN, DECON AS, NILSSON JOHN THORLEIF, BORCH, BJOERN, NILSSON, JOHN, THORLEIF
Application year: 2001
Main classification: A61C5
IPC codes: A61C5, A61C17