Abstract:
This invention provides an oral apparatus and method capable of alleviating or curing snore and obstructive sleep apnea by applying a negative pressure through a mini oral interface to the oral cavity. The mini oral interface creates a secure connection to mouth and helps a patient&#39;s upper and lower lips closed during sleeping. The negative pressure pulls the tongue toward upper palate and also pulls the soft palate forward as well. By moving the tongue and the soft tissue in a forward direction, the patency of the upper airway near the pharynx is maintained to prevent sleep-disordered breathing. The negative pressure will pull the lips inward to close the mouth preventing air from entering the oral cavity from atmosphere. The negative pressure will also pull the soft palate into contact with the rear surface of the tongue to create a seal that prevents the air from entering the oral cavity through the nasal airway.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention is related to methods and systems capable of reducing obstruction of the upper airway in obstructive sleep apnea (OSA) and snore patients. More particularly, the present invention relates to an oral apparatus that prevents mouth breathing and also provides negative pressure in the oral cavity. 
         [0003]    2. Prior Art 
         [0004]    Obstructive sleep apnea (OSA) is a condition in which repeated collapses in the patient&#39;s airway during inhalation causes a cessation of breathing during sleep. During inhalation, air pressure in the lungs and respiratory passages is reduced. If during this time, the tone of the muscles in the upper-airway is reduced, the airway tends to collapse. As the airway begins to occlude prior to an apnea episode, the patient often begins to snore. Snoring is an effort to try to combat the collapsed airway. These obstructions occur in different locations along the respiratory pathway in different patients, but the two common locations are the oropharynx or the nasopharynx. 
         [0005]    People with moderate to severe OSA experience daytime sleepiness, fatigue, and poor concentration. In addition to these immediate problems, research has shown that patients with OSA use more medical resources, have an increased risk of medical disability, and finally have a higher mortality rate. Patients with severe OSA are estimated to have a three to six fold increased risk of mortality considering all causes. OSA is also implicated in many cardiovascular conditions, such as systemic hypertension and some degree of pulmonary hypertension. It is associated with an increased risk for myocardial infarction, cerebrovascular disease, and cardiac arrhythmia. OSA causes excessive daytime sleepiness due to interrupted sleeping pattern at night which leads to inability to concentrate. Patients&#39; daily functions are impaired as their neuro-cognitive function is compromised. They are more likely to make errors and run into accidents. Therefore, OSA is a significant medical condition with serious negative outcomes if left untreated. 
         [0006]    There are several current treatment options for OSA patients. Oral appliances are used to treat mild OSA, but they often don&#39;t work well and cause damage to gums and teeth. Several types of surgery are used to treat OSA, however, surgical options are invasive, expensive and painful with recovery periods up to 6 months. The most common treatment for moderate to severe sleep apnea in adults is CPAP, which has 96% market share in OSA therapeutics. A CPAP machine consists of a mask, a pump and a humidifier. The device continuously blows pressurized air into the patient&#39;s nose to keep the airway open during sleep. CPAP is quite effective; however, it has unpleasant side effects such as dry throat and nose congestion. Patients who use CPAP often feel bloated in the morning and experience headaches. The machine is noisy and uncomfortable for the user and their partner. CPAP is currently the first-line and gold standard treatment, but it suffers low compliance due to significant side effects. 
         [0007]    It has been proposed to apply a negative pressure to the patient&#39;s oral cavity to pull the tongue and soft palate forward to maintain the patency of the airway, as an improvement over CPAP, for example, U.S. Pat. No. and Patent Publication Nos. 5,957,133, 2005/0166928, and 2006/0096600. While promising in theory, these prior arts comprise relatively large structures to engage the teeth and/or to retain the tongue. Moreover, negative pressure is applied directly on the soft tissues of the tongue to hold the tongue within the cavity. These approaches tend to occupy a lot of space in the oral cavity, which may cause discomfort and damage to large area of teeth, gum, and soft tissues. At the same time, the presence of such larger devices may induce excess saliva secretion and elicit the gag reflex. The other major disadvantage of these approaches is that the oral devices are anatomically dependent, requiring special technicians to customize the interface for each individual patient. 
         [0008]    Therefore, it is one objective of the present invention to provide alternative and improved methods and apparatus for treating obstructive sleep apnea and snoring. It is another objective of the present invention to provide minimally intrusive methods and apparatus with components that are comfortable and convenient to use. It is still an objective of the present invention to provide methods and apparatus that avoid contacting the portions of the oral cavity that cause discomfort, induce excess saliva, and trigger the gag reflex. The methods and apparatus should be simple to implement and to significantly improve patency of a patient&#39;s airway during sleep. At least some of these objectives will be met by the inventions described hereinafter. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention provides an oral apparatus and method capable of alleviating or curing snoring and obstructive sleep apnea by creating a small oral interface and applying negative pressure through the small interface to the oral cavity. The small interface creates a secure connection to mouth and prevents disengaging from patient&#39;s mouth during sleep. The negative pressure pulls the tongue toward upper palate and also pulls the soft palate forward. By moving the tongue and the soft tissue in a forward direction, the patency of the upper airway near the pharynx is maintained to prevent sleep-disordered breathing. The oral apparatus will pull the lips inward to close the mouth preventing air from entering the oral cavity from atmosphere. The negative pressure will also pull the soft palate into contact with the rear surface of the tongue to create a seal that prevents the air entering the oral cavity through the nasal airway. This therapy connected to a negative pressure source but only required partial active pumping time and minimal airflow, which is very energy-efficient and quiet. 
         [0010]    In one embodiment, the present invention provides an oral apparatus, comprising: an upper component and a lower component, which can be temporarily attached to the skin around upper lip and lower lip separately; a connecting part to connect and/or disconnect, as well as to control a distance between the upper and lower components; a retractable part, which connects to the connecting part and may exert a pulling force to close the lips and mouth. The upper and lower components may only be applied to lip region away from the opening of the mouth to allow for the mouth to open partially. The retractable part not only provides a mechanism to close a user&#39;s mouth, meanwhile, it may also provide a mechanism to allow the user to open the mouth at certain conditions (such as coughing, sneezing, and yawning, etc.). The oral apparatus may further connect to a negative pressure source and automatically detect if the user&#39;s mouth is open or other physiological conditions such as sleep stages. If the user&#39;s mouth is open, the retractable part may voluntarily close the user&#39;s mouth and prevent it from opening. The negative pressure may only be applied when the user&#39;s mouth is closed so that the treatment can be more efficient, quiet, and comfortable for the users. The oral apparatus can also be used in combination with constant positive airway pressure devices, oral appliances, or other sleep apnea therapies to prevent mouth breathing. 
         [0011]    In another embodiment, the present invention provides an oral apparatus, wherein the retractable part is a flexible wire connected to a fixed anchor. 
         [0012]    In another embodiment, the present invention provides an oral apparatus, wherein the retractable part is a piston-type retractable part. 
         [0013]    In another embodiment, the present invention provides an oral apparatus, wherein the retractable part is a bellows-type retractable part. 
         [0014]    In another embodiment, the present invention provides an oral apparatus, wherein the retractable part is a magnetic retractable part. 
         [0015]    In another embodiment, the present invention provides an oral apparatus, wherein the retractable part is a spring-type retractable part. 
         [0016]    In another embodiment, the present invention provides an oral apparatus, wherein the retractable part is a plate-type retractable part. 
         [0017]    In another embodiment, the present invention provides an oral apparatus, wherein the retractable part is a self-retracting-drum-type retractable part. 
         [0018]    In yet another embodiment, the present invention provides an oral apparatus, comprising: an upper component and a lower component, which can be temporarily attached to the skin around upper lip and lower lip separately; an active connecting part to connect and/or disconnect as well as to control a distance between the upper and lower components. The active connecting part may further comprise an actuator and a controller. 
         [0019]    In still another embodiment, the present invention provides a method, comprising: applying an upper attaching component to the skin around the upper lip and a lower attaching component to a user&#39;s skin around the lower lip without occluding the opening of the mouth; detecting a relative distance between the upper and lower attaching components to judge if the user&#39;s mouth is open; if the user&#39;s mouth is open, activating an actuator to close the user&#39;s mouth. The method may further comprise: judging if the user&#39;s mouth is closed, if yes, applying a negative pressure to oral cavity via a conduit. 
     
    
     
       BRIEF SUMMARY OF THE DRAWINGS 
         [0020]    The objects, spirits and advantages of the preferred embodiments of the present invention will be readily understood by the accompanying drawings and detailed descriptions, wherein: 
           [0021]      FIG. 1A  and  FIG. 1B  show schematic diagrams with front views of an oral apparatus according to the first embodiment of the present invention; 
           [0022]      FIG. 1C  to  FIG. 1I  show schematic diagrams of different retractable parts may be adopted in the first embodiment of the present invention. 
           [0023]      FIG. 2A  and  FIG. 2B  show schematic diagrams with front views of an oral apparatus according to  FIG. 1A  and  FIG. 1B  being used in combination with a conduit and a negative pressure source; 
           [0024]      FIG. 3  shows a schematic diagram with a front view of an oral apparatus according  FIG. 2A  and  FIG. 2B  further comprising an extensible link(s) between the upper and lower attaching components; 
           [0025]      FIG. 4A  and  FIG. 4B  show schematic diagrams with front views of an oral apparatus according to the second embodiment of the present invention; 
           [0026]      FIG. 4C  and  FIG. 4D  show schematic diagrams of actuators and controllers of an active connecting part according to  FIG. 4A  and  FIG. 4B ; 
           [0027]      FIG. 5A  to  FIG. 5D  show schematic diagrams with front views of an oral apparatus according to  FIG. 4A  to  FIG. 4D  being used in combination with a conduit and a negative pressure source; 
           [0028]      FIG. 6  to  FIG. 12  show schematic diagrams of variations of attaching components of an oral apparatus according to  FIG. 5A  and  FIG. 5B ; 
           [0029]      FIG. 13A  shows a perspective diagram of the oral apparatus according to of  FIG. 6  with an active connecting part disconnected; 
           [0030]      FIG. 13B  shows a perspective diagram of the oral apparatus according to  FIG. 6  with an active connecting part connected in a mouth-closed condition; 
           [0031]      FIG. 13C  shows a perspective diagram of the oral apparatus according to  FIG. 6  with an active connecting part connected in a mouth-open condition; 
           [0032]      FIG. 14  shows a perspective diagram of the oral apparatus according to  FIG. 13  further comprising an extensible link(s); 
           [0033]      FIG. 15  shows a perspective diagram of the oral apparatus according to  FIG. 13  further comprising a sensor(s) to detect physiological conditions; 
           [0034]      FIG. 16  shows a perspective diagram of the oral apparatus according to  FIG. 13  further comprising a liquid collector; 
           [0035]      FIG. 17  shows a perspective exploded diagram of the liquid collector according to  FIG. 16 ; 
           [0036]      FIG. 18  shows the liquid collector according to  FIG. 16 , wherein the left side view shows a cross-section view of the liquid collector and the right side view shows a fragmentarily cross-section view of the liquid collector; 
           [0037]      FIG. 19  shows a perspective diagram of the liquid collector according to  FIG. 16  further comprising a filter valve and/or a sensor(s); 
           [0038]      FIG. 20  shows a flow chart of a method according the second embodiment of the present invention for automated control of negative pressure pumping according to whether a user&#39;s mouth is open or closed. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0039]    Reference will now be made in detail to the present exemplary embodiments, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts. 
         [0040]      FIG. 1A  and  FIG. 1B  show schematic diagrams of an oral apparatus according to the first embodiment of the present invention.  FIG. 1A  demonstrates the oral apparatus with a user&#39;s mouth closed and  FIG. 1B  with a user&#39;s mouth open. The oral apparatus comprises an upper attaching component  110 , a lower attaching component  120 , an anchoring part  130 , a connecting part  140 , and a retractable part  150 . The attaching components  110  and  120  can be of various thickness and flexibility, and is capable of adhering firmly to the skin. Potential materials of the attaching components include silicone, flexible plastic, latex, gel, hydrogel, acrylic gel as well as other materials coated with an adhesive substance. The adhesive upper and lower attaching components  110  and  120  can be temporarily attached to the skin around the upper and lower lips, respectively. The anchoring part  130  can be attached or fixed on the upper attaching component  110 , and the retractable part  150  can be attached or fixed on the lower attaching component  120 . The connecting part  140  has two ends connecting to the anchoring part  130  and retractable part  150 , respectively.  FIG. 1C  shows a schematic diagram of the connecting part  140  connecting to the retractable part  150 , wherein the retractable part  150  is a fixed retractable part and the connecting part  140  is an extensible connecting part. The fixed retractable part  150  comprises an anchor  1501 . The anchor  1501  is fixed in the retractable part  150 , i.e., the position of the anchor  1501  is unchangeable relative to the fixed retractable part  150 . The extensible connecting part  140  is elastic and its length can be changed. Please refer to  FIG. 1A  and  FIG. 1B , in the initial condition, the length of the extensible connecting part  140  can maintain a user&#39;s mouth closed. At certain conditions when the user needs to open the mouth (such as coughing, sneezing, and yawning, etc.), upper and lower lips apply a pulling force via the anchoring part  130  and the retractable part  150 , respectively, to stretch the length of the extensible connecting part  140 . Therefore, the distance between the anchoring part  130  and the retractable part  150  increases and the user&#39;s mouth can be opened. After the specific conditions (such as sneezing) finish, the upper and lower lips stop applying a pulling force via the anchoring part  130  and the retractable part  150 , respectively, to the extensible connecting part  140 , the extensible part  140  can restore its initial length due to its elastic property. Therefore, the extensible connecting part  140  applies a force (restoring force) to the upper and lower lips to close the user&#39;s mouth. In the first embodiment of the present invention, the connecting part  140  and the retractable part  150  can have different variations to provide a mechanism to allow a user to open the mouth when the user needs; when the user does not need to open the mouth, the oral apparatus helps close the user&#39;s mouth. 
         [0041]      FIG. 1D  is a variation of the connecting part  140  and retractable part  150  according to the first embodiment of the present invention. The retractable part  150  is a piston-type retractable part, which comprises a cylinder  1502  and a piston  1503 . The connecting part  140  has a fixed length and is connected to the piston  1503 . Please refer to  FIG. 1A  and  FIG. 1B , in the initial condition, the position of the piston  1503  and the length of the connecting part  140  can maintain a user&#39;s mouth closed. The piston  1530  is kept at a balanced position and divided the cylinder  1502  into two, left and right, isolated compartments. At certain conditions when the user needs to open the mouth (such as coughing, sneezing, and yawning, etc.), the connecting part  140  pulls the piston  1503  toward the left side, as shown by the arrow direction of  FIG. 1D . As a consequence, the pressure in the right compartment  1504  decreases and the pressure in the left compartment increases. Therefore, the distance between the anchoring part  130  and the retractable part  150  increases and the user&#39;s mouth can be opened. After the specific conditions (such as sneezing) finish, the connecting part  140  stops pulling the piston  1503  toward left. As the pressure in the left compartment is higher than the pressure in the right compartment  1504 , the piston  1503  is pushed back to the original balanced position. Therefore, the extensible connecting part  140  is pulled back to its initial conditions and keeps the user&#39;s mouth closed. 
         [0042]      FIG. 1E  is another variation of the connecting part  140  and retractable part  150  according to the first embodiment of the present invention. The retractable part  150  is a bellows-type retractable part, which comprises a bellows  1505 . The connecting part  140  has a fixed length and is connected to the bellows  1505 . Please refer to  FIG. 1A  and  FIG. 1B , in the initial condition, the position of one end of the bellows  1505  and the length of the connecting part  140  can maintain a user&#39;s mouth closed. At certain conditions when the user needs to open the mouth (such as coughing, sneezing, and yawning, etc.), the connecting part  140  pulls the one end of the bellows  1505  toward the left side, as shown by the arrow direction of  FIG. 1E . As a consequence, the distance between the anchoring part  130  and the bellows-type retractable part  150  increases and the user&#39;s mouth can be opened. After the specific conditions (such as sneezing) finish, the connecting part  140  stops pulling the one end of the bellows  1505  toward left. As the bellows  1505  tends to return to its initial volume, i.e., the one end of the bellows  1505  tends to return to its initial position, the connecting part  140  is pulled back toward right to its initial conditions and keeps the user&#39;s mouth closed. 
         [0043]      FIG. 1F  is yet another variation of the connecting part  140  and retractable part  150  according to the first embodiment of the present invention. The retractable part  150  is a magnetic-type retractable part, which comprises a first magnetic part  1506  and a second magnetic part  1507 . The connecting part  140  has a fixed length and is connected to the first magnetic part  1506 . Please refer to  FIG. 1A  and  FIG. 1B , in the initial condition, the position of the first magnetic part  1506  and the length of the connecting part  140  can maintain a user&#39;s mouth closed. At certain conditions when the user needs to open the mouth (such as coughing, sneezing, and yawning, etc.), the connecting part  140  pulls the first magnetic part  1506  toward the left side, as shown by the arrow direction of  FIG. 1F . As a consequence, the distance between the anchoring part  130  and the magnetic-type retractable part  150  increases and the user&#39;s mouth can be opened. After the specific conditions (such as sneezing) finish, the connecting part  140  stops pulling the first magnetic part  1506  toward left. As the second magnetic part  1507  pushes the first magnetic part  1506  back to its initial position, the connecting part  140  is pulled back toward right to its initial conditions and keeps the user&#39;s mouth closed. 
         [0044]      FIG. 1G  is yet another variation of the connecting part  140  and retractable part  150  according to the first embodiment of the present invention. The retractable part  150  is a spring-type retractable part, which comprises an anchor  1508  and a spring  1509 . The spring  1509  has a first end and a second end, wherein the first end connects to the connecting part  140  and the second end connects to the anchor  1508 . The connecting part  140  has a fixed length. Please refer to  FIG. 1A  and  FIG. 1B , in the initial condition, the position of the first end of the spring  1509  and the length of the connecting part  140  can maintain a user&#39;s mouth closed. At certain conditions when the user needs to open the mouth (such as coughing, sneezing, and yawning, etc.), the connecting part  140  pulls the first end of the spring  1509  toward the left side, as shown by the arrow direction of  FIG. 1G . As a consequence, the distance between the anchoring part  130  and the spring-type retractable part  150  increases and the user&#39;s mouth can be opened. After the specific conditions (such as sneezing) finish, the connecting part  140  stops pulling the first end of the spring  1509  toward left. As the spring  1509  tends to return to its initial length, i.e., the first end of the spring  1509  tends to return to its initial position, the connecting part  140  is pulled back toward right to its initial conditions and keeps the user&#39;s mouth closed. 
         [0045]      FIG. 1H  is still another variation of the connecting part  140  and retractable part  150  according to the first embodiment of the present invention. The retractable part  150  is a plate-type retractable part, which comprises a plate  1510 . The plate  1510  has a first end and a second end, wherein the first end connects to the connecting part  140  and the second end connects to a fixed position of the plate-type retractable part  150 . The connecting part  140  has a fixed length. Please refer to  FIG. 1A  and  FIG. 1B , in the initial condition, the position of first end of the plate  1510  and the length of the connecting part  140  can maintain a user&#39;s mouth closed. At certain conditions when the user needs to open the mouth (such as coughing, sneezing, and yawning, etc.), the connecting part  140  pulls the first end of the plate  1510  toward the left side, as shown by the arrow direction of  FIG. 1H . As a consequence, the distance between the anchoring part  130  and the plate-type retractable part  150  increases and the user&#39;s mouth can be opened. After the specific conditions (such as sneezing) finish, the connecting part  140  stops pulling the first end of the plate  1510  toward left. As the plate  1510  tends to return to its initial condition, i.e., the first end of the plate  1510  tends to return to its initial position, the connecting part  140  is pulled back toward right to its initial conditions and keeps the user&#39;s mouth closed. 
         [0046]      FIG. 1I  is yet still another variation of the connecting part  140  and retractable part  150  according to the first embodiment of the present invention. The retractable part  150  is a self-retracting-type retractable part, which comprises a self-retracting drum  1511 . The connecting part  140  has a fixed length and is connected to the self-retracting drum  1511 . Please refer to  FIG. 1A  and  FIG. 1B , in the initial condition, the position of one end of the self-retracting drum  1511  and the length of the connecting part  140  can maintain a user&#39;s mouth closed. At certain conditions when the user needs to open the mouth (such as coughing, sneezing, and yawning, etc.), the connecting part  140  pulls the one end of the self-retracting drum  1511  toward the left side, as shown by the arrow direction of  FIG. 1I . As a consequence, the distance between the anchoring part  130  and the self-retracting-type retractable part  150  increases and the user&#39;s mouth can be opened. After the specific conditions (such as sneezing) finish, the connecting part  140  stops pulling the one end of the self-retracting drum  1511  toward left. As the self-retracting drum  1511  tends to return to its initial condition, i.e., the one end of the self-retracting drum  1511  tends to return to its initial position, the connecting part  140  is pulled back toward right to its initial conditions and keeps the user&#39;s mouth closed. 
         [0047]      FIG. 2A  and  FIG. 2B  demonstrate the front views of an oral apparatus according to  FIG. 1A  and  FIG. 1B  being used as a negative pressure sleep apnea treatment device. The oral apparatus further comprises a fluid conduit  170 . The first end of the fluid conduit  170  is attached to the lower attaching component  120  and enters a user&#39;s oral cavity. The second end of the fluid conduit  170  is connected to a negative pressure source (not shown). The negative pressure source can draw air out of oral cavity and thus produce a negative pressure environment to pull the tongue, soft palate and other soft tissue forward to maintain the airway patency reducing snoring and apnea episodes. The oral apparatus can further comprise a fluid conduit attachment part  160 . The fluid conduit attachment part  160  is used to attach the fluid conduit  170  on the lower attaching component  120 . Please notice that the retractable part  150  can be installed on the fluid conduit  170  or the lower attaching component  120 . In one preferred embodiment of the present invention, the anchoring part  130  can have a design to allow the upper attaching component  110  to separate with the lower attaching component  120 , as described in the following section. Therefore, the oral apparatus can further comprise an extensible link(s)  180 . The extensible link is flexible and can connect the upper attaching component  110  and the lower attaching component  120  to prevent loss of any of the attaching components due to separation, as shown in  FIG. 3 . 
         [0048]      FIG. 4A  and  FIG. 4B  are schematic diagrams with front views of an oral apparatus according to the second embodiment of the present invention.  FIG. 4A  is the schematic diagram with a user&#39;s mouth closed and  FIG. 4B  with a user&#39;s mouth open. The oral apparatus comprises an upper attaching component  210 , a lower attaching component  220 , an anchoring part  230 , a connecting part  240 , and a retractable part  250  (as shown in  FIG. 4C ). The upper and lower attaching components  210  and  220  can be of various thickness and flexibility, and is capable of adhering firmly to the skin. Potential materials of the attaching components include silicone, flexible plastic, latex, gel, hydrogel, acrylic gel as well as other materials coated with an adhesive substance. The adhesive upper and lower attaching components  210  and  220  can be temporarily attached to the skin around the upper and lower lips, respectively. The anchoring part  230  can be attached or fixed on the upper attaching component  210 . The connecting part  240  is connected to the anchoring part  230  on one end and connected to the retractable part  250  on the other end.  FIG. 4C  and  FIG. 4D  are schematic diagrams of the connecting part  240  formed of a wire  240  being connected to the retractable part  250 .  FIG. 4C  is the schematic diagram with a user&#39;s mouth closed and  FIG. 4D  with a user&#39;s mouth open. The retractable part  250  further comprises a controller  251  and an actuator  252 . The connecting part  240  connects to the retractable part  250  via an engaging point  253 . The controller  251  determines the conditions and activates a motion of the actuator  252  to apply an inward pulling force via the connecting part  240  on a user&#39;s upper lip in order to close the user&#39;s mouth (as shown in  FIG. 4A  and  FIG. 4C ). The controller  251  may also activate another motion of the actuator  252  to apply an outward pushing force on a user&#39;s upper lip in order to open the user&#39;s mouth. Please notice that in the second embodiment of the present invention, the connecting part  240  has to be a rigid material that the actuator  252  can pull it inwardly or push it outwardly to adjust the distance between the anchoring part  230  and the retractable part  250 , and thus can close or open the user&#39;s mouth. Please refer to  FIG. 4A . In the second embodiment of the present invention, the oral apparatus further comprises a connecting catheter  270 . The connecting part  240  connects to the retractable part  250  via the connecting catheter  270  to prevent the connecting part  240  having contact or friction with a user&#39;s face. Moreover, the oral apparatus may further comprise a connecting catheter attachment part  260 . The connecting catheter attachment part  260  is used to attach the connecting catheter  270  to the lower attaching component  220 . 
         [0049]      FIG. 5A  and  FIG. 5B  demonstrate the front views of an oral apparatus according to  FIG. 4A  and  FIG. 4B  being used as a negative pressure sleep apnea treatment device. The oral apparatus further comprises a fluid conduit  280 . The first end of the fluid conduit  280  is attached to the lower attaching component  220  and enters a user&#39;s oral cavity. The second end of the fluid conduit  280  is connected to a negative pressure source  290  (not shown). The negative pressure source  290  can draw air out of oral cavity and thus produce a negative pressure environment to pull the tongue, soft palate and other soft tissue forward to maintain the airway patency reducing snoring and apnea episodes. In one preferred embodiment of the present invention, the negative pressure source  290  can be integrated with the retractable part  250  and the controller  251  can be connected with the negative pressure source  290  to control on and off of the negative pressure source  290 , as shown in  FIG. 5C  and  FIG. 5D . Please refer to  FIG. 5A  and  FIG. 5B , the connecting catheter  270  and the fluid conduit  280  can be integrated as one piece. The integral piece of the fluid conduit  280  and the connecting catheter  270  can be attached to the lower attaching component  220  via the fluid conduit attachment part  260 . In one preferred embodiment of the present invention, the anchoring part  230  can have a design to allow the upper attaching component  210  to separate with the lower attaching component  220 , as described in the following section. Therefore, the oral apparatus can further comprise an extensible link(s) (as shown by  180  in  FIG. 3 ). The extensible link is flexible and can connect the upper attaching component  210  and the lower attaching component  220  to prevent loss of any of the attaching components due to separation. Please further refer to  FIG. 20  accompanying  FIG. 5A  to  FIG. 5D .  FIG. 20  is a flow chart of the method according to the second embodiment of present invention, which automatically applies negative pressure to a user&#39;s oral cavity. The anchoring part  230  is installed or fixed on the upper attaching component  210 . The connecting part  240  has two ends being connected to the anchoring  230  and the engaging point  253 , respectively. In addition, when the actuator  252  pull the engaging point  253  inwardly (i.e., pulling the connecting part  240  inwardly), a user&#39;s mouth can be closed. When the actuator  252  push the engaging point  253  outwardly (i.e., pushing the connecting part  240  outwardly), the user&#39;s mouth can be opened. When the relative distance d between the engaging point  253  and the actuator  252  is equal or larger than a given distance d 1 , i.e. d≧d 1 , it represents a user&#39;s mouth is open. When the relative distance d between the engaging point  253  and the actuator  252  is equal or smaller than another given distance d 2 , i.e. d≦d 2 , it represents a user&#39;s mouth is closed. In one embodiment of the present invention, the controller  251  and other external components can detect the relative distance d between the engaging point  253  and the actuator  252 , which is equivalent to detect a relative distance between a user&#39;s upper lip and lower lip (step  2001 ), and can determine if the user&#39;s mouth is open (step  2002 ). If the user&#39;s mouth is open, i.e. d≧d 1  is detected, the controller  251  can turn off the negative pressure source  290  (step  2003 ), and activate the actuator  252  to pull the connecting part  240  inwardly in order to close the user&#39;s mouth, i.e. until d≦d 2  is detected; then the controller  251  can turn on the negative pressure source  290 . If the user&#39;s mouth is closed, i.e. d≦d 2  is detected, the controller  251  can check if the negative pressure source  290  is turned on (step  2006 ); if the negative pressure source  290  is not turned on, the controller  251  can turn on the negative pressure source  290 . With the above-mentioned process, a user&#39;s mouth can be automatically kept close and applied with negative pressure in the user&#39;s oral cavity. 
         [0050]    As mentioned above, in the first and second embodiments of the present invention, various designs of the anchoring parts  130  and  230  can allow the upper attaching components  110  and  120  to be separated from the lower attaching components  120  and  220 . This also allows a user to temporarily disengage the anchoring parts  130  or  230  to let user to open mouth to drink, speak or perform other activities. 
         [0051]      FIG. 6A  is a schematic diagram of the oral apparatus according to  FIG. 5A  wherein the anchoring part  230  is a mechanical anchoring part. The mechanical anchoring part comprises an anchoring block  231  and an anchoring seat  232 . The anchoring seat  232  is installed and fixed on the upper attaching component  210 , and the anchoring block  231  is connected to the connecting part  240 . The anchoring block  231  and the anchoring seat  232  can be joined and disjoined, which allows a user to manually disengage the mechanical anchoring part to let the user to open mouth to drink, speak or perform other activities, as shown in  FIG. 6B . 
         [0052]      FIG. 7  is a schematic diagram of the oral apparatus according to  FIG. 5A  wherein the anchoring part  230  is a magnetic anchoring part. The magnetic anchoring part comprises a first magnetic sub-part  331  and a second magnetic sub-part  332 . The first magnetic sub-part  331  is installed and fixed on the upper attaching component  210 , and the second magnetic sub-part  332  is connected to the connecting part  240 . The first magnetic sub-part  331  and the second magnetic sub-part  332  can be joined and disjoined, which allows a user to manually disengage the magnetic anchoring part to let the user to open mouth to drink, speak or perform other activities. Besides, the second magnetic sub-part  332  can be a strip having a longitudinal magnetic connection region with infinite joining points to allow for anatomical difference. It can be adjusted by users to accommodate thicker or thinner lips or provide tighter or looser mouth closing as desired. Either of the above mentioned magnetic sub-parts  331  and  332  can be made of paramagnetic materials. 
         [0053]      FIG. 8  is a schematic diagram of the oral apparatus according to  FIG. 5A  wherein the anchoring part  230  is another mechanical anchoring part. The mechanical anchoring part comprises a male connector  431  and a female connector  432 . The male connector  431  is installed and fixed on the upper attaching component  210 , and the female connector  432  is connected to the connecting part  240 . The male connector  431  and the female connector  432  can be joined and disjoined, which allows a user to disengage the mechanical connector temporarily and manually to let the user to open mouth to drink, speak or perform other activities. Besides, the male connector  431  can have a plural of male connector sub-parts to allow for anatomical difference. It can be adjusted by users to accommodate thicker or thinner lips or provide tighter or looser mouth closing as desired. 
         [0054]      FIG. 9  is a schematic diagram of the oral apparatus according to  FIG. 5A  wherein the anchoring part  230  is a frictional anchoring part. The frictional anchoring part  230  may comprise a sunken structure  531  and a protruding structure  532 . The sunken structure  531  is installed and fixed on the upper attaching component  210 , and the protruding structure  532  is connected to the connecting part  240 . The sunken structure  531  and the protruding structure  532  can be joined and locked by frictional forces and can also be disjoined by overcoming the frictional forces, which allows a user to disengage the frictional anchoring part temporarily and manually to let the user to open mouth to drink, speak or perforin other activities. Besides, the protruding structure  532  can be inserted into different locations on the sunken structure  531  to allow for anatomical difference. It can be adjusted by users to accommodate thicker or thinner lips or provide tighter or looser mouth closing as desired. 
         [0055]      FIG. 10  is a schematic diagram of the oral apparatus according to  FIG. 5A  wherein the anchoring part  230  is an adhesive anchoring part. The adhesive anchoring part  230  may comprise a first adhesive part  631  and a second adhesive part  632 . The first adhesive part  631  is installed and fixed on the upper attaching component  210 , and the second adhesive part  632  is connected to the connecting part  240 . The first adhesive part  631  and the second adhesive part  632  can be attached and detached, which allows a user to separate the adhesive anchoring part temporarily and manually to let the user to open mouth to drink, speak or perform other activities. Besides, the first adhesive part  631  can be attached onto different locations of the second adhesive part  632  to allow for anatomical difference. It can be adjusted by users to accommodate thicker or thinner lips or provide tighter or looser mouth closing as desired. 
         [0056]      FIG. 11  is a schematic diagram of the oral apparatus according to  FIG. 5A  wherein the anchoring part  230  is a reclosable fastening part. The reclosable fastening part  230  may be fabric fasteners such as Dual Lock or Velcro tapes. Using Velcro tape as an example, the reclosable fastening part  230  may comprise a tiny-hooks part  731  and a hairy-loops part  732 . The tiny-hooks part  731  can be installed and fixed on the upper attaching component  210 , and the hairy-loops part  732  can be connected to the connecting part  240 . The tiny-hooks part  731  and the hairy-loops part  732  can be attached and detached, which allows a user to separate the reclosable fastening part temporarily and manually to let the user to open mouth to drink, speak or perform other activities. Besides, the tiny-hooks part  731  can be attached onto different locations of the hairy-loops part  732  to allow for anatomical difference. It can be adjusted by users to accommodate thicker or thinner lips or provide tighter or looser mouth closing as desired. 
         [0057]      FIG. 12  is a schematic diagram of the oral apparatus according to  FIG. 5A  wherein the anchoring part  230  is a lasso-pole anchoring part. The lasso-pole anchoring part  230  comprises a pole part  831  and a lasso part  832 . The pole part  831  may have multiple pole structures. The pole part  831  can be installed and fixed on the upper attaching component  210 , and the lasso part  832  can be connected to the connecting part  240 . The pole part  831  and the lasso part  832  can be hooked and unhooked, which allows a user to separate the lasso-pole anchoring part temporarily and manually to let the user to open mouth to drink, speak or perform other activities. Besides, the lasso part  832  can be hooked onto different locations of the pole part  831  to allow for anatomical difference. It can be adjusted by users to accommodate thicker or thinner lips or provide tighter or looser mouth closing as desired. 
         [0058]    Please refer to  FIG. 13A ,  FIG. 13B , and  FIG. 13C  to further understand the structure of the oral apparatus of the present invention.  FIG. 13A  is a perspective diagram of the oral apparatus according to  FIG. 6 , wherein the oral apparatus is in a disengaged condition.  FIG. 13B  is a perspective diagram of the oral apparatus according to  FIG. 6  wherein the oral apparatus is in an engaged condition with a user&#39;s mouth being open.  FIG. 13C  is a perspective diagram of the oral apparatus according to  FIG. 6 , wherein the oral apparatus is in an engaged condition with a user&#39;s mouth being closed. As mentioned above, the oral apparatus can further comprise an extensible link(s)  180 . The extensible link  180  is flexible and can connect the upper attaching component  210  and the lower attaching component  220  to prevent loss of any of the attaching components due to separation, as shown in  FIG. 14 . 
         [0059]      FIG. 15A  is a variation of the oral apparatus according  FIG. 13A  further comprising a sensor to detect a user&#39;s physiological or other conditions. The oral apparatus may further comprise a sensor component  1510  to detect a user&#39;s body conditions, such as a user&#39;s flow conditions of nasal breathing in order to judge if the user&#39;s breathing pattern is normal, with difficulty, or with pauses, etc. In one preferred embodiment, the connecting part  240  may further comprise a sensor component  1510  with sensing capability and electrical connection to deliver signal of body conditions sensed by the sensor component  1510  to a medical system (not shown) or the controller  251  (not shown in  FIG. 15A  and  FIG. 15B ). In another preferred embodiment of the present invention, the sensor component  1510  can be installed on the anchoring block  231 . 
         [0060]      FIG. 16  is a variation of the oral apparatus according to  FIG. 13A , further comprising a liquid canister. The connecting part  240  and the fluid conduit  280  may connect to the retractable part  250  (not shown) and the negative pressure source  290  (not shown), respectively. The liquid canister  1600  may comprise a liquid chamber, a connector  1640 , a fluid conduit  1660 , and a connecting part  1670 . The liquid chamber may comprise an upper lid  1610 , a lower lid  1630  and a liquid absorber  1620 . The liquid absorber  1620  may comprise one or more channels  1621  and/or spaces  1622  to maintain air flow patency within the liquid chamber even when the liquid absorber  1620  is absorbed with liquid. The fluid conduit  1660  connects to the negative pressure source  290  and the connecting part  1670  connects to the retractable part  250 .  FIG. 17  shows an exploded view of the liquid collector according to  FIG. 16 . The fluid conduit  280  can be coupled to one end of the liquid chamber to connect to the fluid conduit  1660 . The connecting part  240  can be coupled with the connector  1640  to connect to the connecting part  1670 . Therefore, the air conduit  280  can be connected to the negative pressure source  290  via the fluid conduit  1660 , and the connecting part  240  can be connected to the retractable part  250  via the connecting part  1670 . In one preferred embodiment, the liquid canister  1600  may further comprise a connecting catheter  1650  similar to the connecting catheter  270 , in order to enclose and protect the connecting part  1670 .  FIG. 18  shows the liquid canister  1600 , in which the left side shows a cross-section view of the liquid canister  1600  and the right side shows a fragmentarily cross-section view of the liquid canister  1600 . 
         [0061]      FIG. 19  shows another variation of the liquid canister  1600  of the present invention. The liquid canister  1600  may further comprise a filter  1940 . The filter  1940  has a property to allow only gas to pass through it, thus when the liquid chamber is filled with saliva and water, the liquid cannot pass through the filter  1940 . The condition of the liquid canister  1600  being filled with saliva or water can be determined by sensing the pressure or humidity in the fluid conduit  1660 . The liquid canister  1600  may further comprise a pressure sensor  1910  installed in the fluid conduit  1660  or the liquid chamber to measure the pressure within the fluid conduit  1660  or the liquid chamber. The signal from the pressure sensor  1910  can be transmitted to an external system or the controller  251  via a sensing wire  1920  enclosed by a connecting catheter  1930 . In another embodiment, the liquid canister  1600  may further comprise a humidity sensor  1910  installed in the fluid conduit  1660  or the liquid chamber to measure the humidity within the fluid conduit  1660  or the liquid chamber. The signal from the humidity sensor  1910  can be transmitted to an external system or the controller  251  via a sensing wire  1920  enclosed by a connecting catheter  1930 . 
         [0062]    In addition to the specific uses described above, other embodiments and uses of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. All documents referenced herein are specifically and entirely incorporated by reference. The specification and examples should be considered exemplary only with the true scope and spirit of the invention indicated by the following claims. As will be easily understood by those of ordinary skill in the art, variations and modifications of each of the disclosed embodiments can be easily made within the scope of this invention as defined by the following claims.