GB2264868A

GB2264868A - Mandibular advancement device

Info

Publication number: GB2264868A
Application number: GB9304724A
Authority: GB
Inventors: Robert Mateljan
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-03-06
Filing date: 1993-03-08
Publication date: 1993-09-15
Also published as: GB9304724D0

Abstract

An oral device is disclosed for preventing and/or reducing obstruction of the upper air passageway by the back of the tongue. The device is to be located in the oral cavity of a user and comprises, in one example, members 12 having upper and lower surfaces 14, 16 which engage the user's maxillary and mandibular dental arches respectively. The upper and lower surfaces are spaced so that the mandible is placed in a forwardly offset position relative to its normal position. The spacing also tensions the masticatory muscles to maintain the device in place. The device is intended for use in preventing or reducing snoring and/or obstructive sleep apnea. <IMAGE>

Description

f?Mandibular Advancement Device THIS INVENTION relates to a device intended for use in preventing or reducing snoring and/or obstructive sleep apnea.

More specifically the invention relates to an oral device intended to be fitted onto the dental arch of the user prior to sleep.

One common cause of snoring is when the upper airway or pharynx is partly obstructed by the back of the tongue. Due to the obstruction air is forced through a restricted passageway thereby creating a noisy vibration of soft palate pharyngeal tissue. In the case of obstructive sleep apnea, (O.S.A.), when the person is asleep the tongue can sometimes completely block the upper airway thereby preventing air from entering the lungs. This obstruction is not usually broken unless the person awakes and opens the airway by pulling the tongue forward. As a result a person with O.S.A. will not sleep well and is usually a loud snorer.

Treatment of such a condition has been by either surgical or non-surgical methods.

The non-surgical approach has seen the proposal of various anti-snoring devices. The main types have been devices which prevent nasal breathing and encourage oral breathing such as a nasal clip; devices which encourage nasal breathing, for example a nasal expander; and devices which prevent oral breathing and encourage nasal breathing such as an oral screen. However practical tests have established doubts about the effectiveness of such devices.

It has been known as early as 1902 that forcing the mandible or lower jaw forward aided in the treatment of airway obstruction by the back of the tongue in humans.

In the early 1980's an oral device called a Mandibular Occlusal Repositioning Appliance (M.O.R.A.) was used in dentistry for the treatment of tempero mandibular joint disfunction. It was noticed that a number of patients being treated for tempero mandibular joint disfunction had a significant improvement in their sleeping patterns and reduction of snoring whilst wearing the M.O.R.A.

The M.O.R.A. is an acrylic appliance which follows the contour of the maxillary dental arch. It fits accurately over the entire lingual and occlusal surfaces, and approximately one to two millimetres over the labial and buccal surfaces of the maxillary teeth. The under surface the appliance is. smooth, except that in the region of the anterior teeth there is a ramp which is angled to the back of the mouth. Its purpose is to engage the mandibular anterior teeth when the wearer bits up thereby guiding the mandible forward in a protrusive position.

It has been found during hospital tests that the M.O.R.A. is useful in assisting patients suffering from cyclic snoring and obstructive sleep apnea, that is when the airway is completely blocked off by the tongue.

A disadvantage of the M.O.R.A. is that the device relies on the voluntary mouth motions of the user, such tightening and clenching in order to keep the mandible in the protrusive position. As a result problems can develop when the user is asleep and the muscles in the jaw relax causing the mandibular anterior teeth to disengage from the device thereby returning the mandible to its normal position in relation to the maxilla. As a result the user begins to snore.

It is a broad object of the present invention to provide an oral device to prevent or reduce snoring and/or obstructive sleep apnea caused by the obstruction of the upper air passageway by the back of the tongue which when worn does not rely on voluntary tightening or clenching of the masticatory muscles in order to keep the device in position so that when the user is asleep the chances of the device becoming displaced are remote.

Thus in one form the invention resides in an oral device for preventing and/or reducing obstruction of the upper air passageway by the back of the tongue which device is adapted for location in the oral cavity of a user and comprises an engaging section having an upper member substantially corresponding to at least a portion of the user's maxillary dental arch for engagement therewith, a lower member substantially corresponding to at least a portion of the user's mandibular dental arch for engagement therewith, said upper member being spaced from said lower member so that when said upper and lower members are in engaged in the oral cavity the user's mandible is in a forwardly offset position relative to its normal position, and wherein the space between said upper and lower members is such that the user's masticatory muscles are tensioned thereby maintaining said oral device in place.

The oral device may comprise of a pair of engaging sections each engaging one side of the users maxillary and mandibular arches.

The engaging sections may be joined by means of a bridge member which may be located at the anterior, posterior, or sides of the engaging sections.

Preferably, a channel is provided in the upper and lower members which is adapted to receive some or all of the posterior teeth of the user. In the case of a user having no maxillary or mandibular teeth the channel is adapted to receive the corresponding maxillary and mandibular edentulous ridge.

The upper and lower members are preferably joined together.

Ideally the upper member and lower member are made integral with each other and are formed from a soft, flexible plastics material.

When the oral device is engaged in the oral cavity the anterior mandibular dental arch is preferably in line with the anterior maxillary dental arch or are preferably located in front of the anterior maxillary dental arch.

Four specific embodiments of the invention will now be described with reference to the accompanying drawings in which: Figure 1 is a front perspective view of an oral device according a first embodiment; Figure 2 is a top plan view of the oral device; Figure 3 is a bottom plan view of the oral device; Figure 4 is a back cross-sectional view of the oral device in engagement with the upper and lower posterior teeth; Figure 5 is a side perspective view of the lower portion of a human skull fitted with the oral device; Figure 6 is a front perspective view of an oral device according to a second embodiment; Figure 7 is a top plan view of the oral device of Figure 6; Figure 8 is a back cross-sectional view of the oral device of Figure 6 in engagement with the upper and lower teeth;; Figure 9 is a side perspective view of the lower portion of a human skull fitted with the oral device of Figure 6; Figure 10 is a front perspective view of an oral device according to a third embodiment; Figure 11 is a front perspective view of an oral device according to a fourth embodiment.

The first embodiment is directed to an oral device 10 for preventing or reducing snoring and/or obstructive sleep apnea caused by obstruction of the upper air passage or pharynx by the back of the tongue. This particular embodiment is intended for use by persons who have all or at least some of their teeth. The oral device 10 as depicted in Figures 1, 2 and 3 comprises a pair of engaging sections 12 which are manufactured from a soft flexible plastics material which is inherently strong in nature. An example of such a material is polyvinylacetate-polyethylene polymer which is commonly used in the construction of protective mouthguards.

Each engaging section 12 is provided with an upper channel 14 and a lower channel 16. The upper channel 14 is made to correspond with the user's upper or maxillary dental arch and the lower channel 16 is made to correspond with the lower or mandibular dental arch. The upper channel 14 is spaced from the lower channel 16. This spacing is important in the workings of the invention and it is essential that the spacing be of a magnitude which ensures that when the oral device is in use the mandible is supported and maintained in a forwardly offset or protrusive position thereby keeping the masticatory muscles tensioned thus preventing the mandible from returning to its normal position.

The spacing differs from patient to patient and is dependent on each patient's specific bone structure and anatomy. It has however been found in trials that the spacing is typically no less than 7mm.

The lower channel 16 is located forward of the upper channel 14 so that when the device is engaged in the mouth the mandibular will be located forwardly offset relative to its normal position.

Each engaging section 12 engages with the posterior teeth of the user as illustrated in Figure 4. Each channel is moulded to accommodate individual configurations of the posterior teeth to enable the device to be engaged with mainly the labial and bucal under-cuts of the teeth thus locking the device in place. The posterior or back teeth comprise the teeth extending from the first pre-molar to the wisdom teeth on each side of the dental arches. The anterior or front teeth comprise the teeth extending from the left canine teeth to the right canine teeth of the dental arches. Each channel 14 and 16 is also provided with a flange portion 18 so that the engaging section 12 extends to cover some 3 to 5 millimetres of the surrounding gingival tissue of the user as seen in Figure 4 to ensure that the oral device is well fitted on the dental arches and is not easily dislodged.

It is advantageous if some of the posterior teeth are missing as this increases the engagement of the device on the distal and mesial under-cuts of remaining posterior teeth thus increasing retention of the oral device in the mouth.

The engaging sections 12 are joined by a bridge member 20 which in this embodiment transverses the upper channels 14 and which is made to correspond to the curve of the upper palate. In other embodiments the bridge member may be provided at any desired location between the engaging sections 12 and can be made to extend between the front, back or side portions of the upper channels or likewise between the lower channels. Alternatively two bridge members can be provided one extending between the upper channels and the other between the lower channels.

Figures 6 to 9 show a second embodiment which is substantially the same as the first embodiment except for the placement, configuration and number of bridge members provided. In this embodiment a first bridge member 200 is provided to connect the upper channels of the engaging section 12 at the front of the oral device. The bridge member 200 is made to configure with the labial surface of the anterior maxillary teeth and surrounding gingival tissue so that in use the bridge member 200 will extend around the labial surface of the anterior maxillary teeth and surrounding gingival tissue. In this embodiment the bridge member 200 is made as an extension of the outer walls 140 of the upper channels 14.

A second bridge member 250 is provided to connect the lower channels 16 together. In this arrangement the bridge member 250 is made to configure with the lingual surface of the anterior mandibular teeth and surrounding gingival tissue such that in use the bridge member 250 will extend around the lingual surface of the anterior mandibular teeth and surrounding gingival tissue so that it is not readily apparent when viewed in front on the user's mouth. In this embodiment the bridge member 250 is made as an extension of the inner walls 160 of the lower channels 16.

In alternative arrangements the oral device may be provided with a single bridge member comprising either bridge member 200 or bridge member 250 to connect the engaging sections 12 together.

At the clinical stage the dental practitioner takes an impression of maxillary and mandibular dental arches and surrounding gingival tissue. At this stage the patient is trained to protrude the mandible to full protrusion and the open vertical dimension is established. The vertical dimension will vary from patient to patient.

A Wax Bite registration is made at this protrusive, open vertical dimension position. With the models of the mouth in this bite position the oral device is then made. During manufacture of the device the upper and lower channels are formed spaced from each other so that the open vertical dimension for each user is achieved.

To position the oral device the patient's mouth is firstly open wide and the oral device is first placed over the mandibular teeth and pushed down. The patient must then protrude the mandible until the maxillary teeth are in line with the device. The mandible is then pulled up so that the device engages the maxillary teeth. - At this stage the anterior mandibular teeth will be in line or lie in front of the anterior maxillary teeth.

As a result of the device the tongue is brought forward and is elevated thus increasing the air passage at the back of the user's throat which results in preventing or reducing snoring and/or obstructive sleep apnea.

As mentioned above, the spacing between the upper and lower channels 14, 16 ensures that the mandible is supported and maintained in a protrusive position, thereby keeping the masticatory muscles under a slight tension thus preventing the mandible from returning to its normal closed position.

As a result the oral device will be maintained in position whilst the user is asleep and until it is consciously removed from the mouth.

Figure 10 shows an oral device 30 according to a third embodiment which is intended for the fully edentulous mouth (one having no teeth at all). In this embodiment a pair of engaging sections 32 are provided each having an upper channel 34 and a lower channel (not shown) spaced from each other. The channels are moulded to accommodate the posterior maxillary and mandibular ridges. Due to the lack of teeth the oral device 30 will not be as well engaged in the mouth cavity of the user as in the situation if the user had some teeth. In order to further engage the oral device 30 there is provided a front portion 38 between the upper channels 34 which is configured to receive the anterior maxillary ridge. Likewise a front portion 40 is also provided between the lower channels to receive the anterior mandibular ridge. The front portions 38 and 40 also serve as bridge members to connect the engaging sections 32.

Figure 11 shows an oral device 50 according to a fourth embodiment which is intended for a mouth which has an edentulous upper maxillary ridge and which has all or some teeth on the mandibular dental arch. In this embodiment a front portion 58 is located between the upper channels 54 of the engaging sections 52 which is configured to receive the maxillary ridge. The lower portion of the engaging sections 52 remains the same as that of the first embodiment wherein the lower channels are configured to only accommodate the posterior mandibular teeth. In this embodiment the front portion 58 also serves as the bridge member to connect the engaging sections 52.

In the case of a fully edentulous mandibular ridge and a maxillary dental arch which has all or some teeth the oral device which is used (not shown) is much the same as that of Figure 11 except the front portion is provided between the lower channels and the upper portion of the engaging sections would remain the same as the first embodiment wherein the upper channels are configured to only accommodate the posterior maxillary teeth.

It should be appreciated that various other changes and modifications may be made to the embodiments described without departing from the spirit and scope of the invention.

Claims

C L R g

I 1. An oral device for preventing and/or reducing obstruction of the upper air passageway by the back of the tongue which device is adapted for location in the oral cavity of a user and comprises an engaging section having an upper member substantially corresponding to at least a portion of the user's maxillary arch for engagement therewith, a lower member substantially corresponding to at least a portion of the user's mandibular arch for engagement therewith, said upper member being spaced from said lower member so that when said upper and lower members are in engaged in the oral cavity the user's mandible is in a forwardly offset position relative to its normal position, and wherein the space between said upper and lower members is such that the user's masticatory muscles are tensioned thereby maintaining said oral device in place.
2. An oral device as claimed in claim 1 wherein said oral device comprises two engaging sections each of which forms corresponding upper and lower members for engaging one side of the user's maxillary and mandibular dental arches.
3. An oral device as claimed in claim 1 and 2 wherein a channel is provided in each of said upper and lower members.
4. An oral device as claimed in claim 3 wherein said channel provided in said upper member is configured to receive the user's maxillary dental arch.
5. An oral device as claimed in claim 3 wherein said channel provided in said lower member is configured to receive the user's mandibular dental arch.
6. An oral device as claimed in any one of claims 3 to 5 wherein said channel is configured to receive at least some of the user's posterior teeth and surrounding gingival tissue.
7. An oral device as claimed in any one of the preceding claims wherein said upper and lower members are integral with each other.
8. An oral device as claimed in any one of claims 2 to 7 wherein a bridge member is provided to connect said pair of engaging sections.
9. An oral device as claimed in claim 8 wherein said bridge member connects said engaging sections at the posterior or anterior or sides of said engaging sections.
10. An oral device as claimed in claim 8 wherein said bridge member is provided as an extension of said upper members or lower members.
11. An oral device as claimed in any one of claims 8 to 10 wherein said bridge member extends around the labial surface of the anterior maxillary teeth or around the lingual surface of the anterior mandibular teeth.
12. An oral device as claimed in any one of the preceding claims wherein when said oral device is engaged in the oral cavity the anterior mandibular dental arch of the user is in line with the anterior maxillary dental arch or is located in front of the maxillary dental arch.
13. An oral device as claimed in any one of claims 2 to 12 wherein a front portion is provided between the upper members and lower members to accommodate the anterior maxillary dental arch or anterior mandibular dental arch or both.
14. An oral device substantially herein described with reference to the accompanying drawings.