Abstract:
Systems and methods selectively stabilize tissue in the oral cavity. The systems and methods implant a first implant element in a bone region within an oral cavity and implant a second implant element in a tongue region within the oral cavity. The systems and methods resist posterior movement of the tongue within the oral cavity by coupling the first implant element to the second implant element within the oral cavity. By coupling, the systems and methods apply force, e.g., tension, between the first and second implant elements.

Description:
RELATED APPLICATION 
   This application is a division of U.S. patent application Ser. No. 10/236,455, filed Sep. 6, 2002 now U.S. Pat. No. 7,216,648, and entitled “Systems and Methods for Moving and/or Restraining Tissue in the Upper Respiratory System.” 

   FIELD OF THE INVENTION 
   The invention is directed to systems and methods for moving and/or restraining tissue in the upper respiratory system, e.g., for the treatment of sleep-related breathing disorders such as snoring, upper airway resistance syndrome and obstructive sleep apnea. 
   BACKGROUND OF THE INVENTION 
   First described in 1965, sleep apnea is a breathing disorder characterized by brief interruptions (10 seconds or more) of breathing during sleep. Sleep apnea is a common but serious, potentially life-threatening condition, affecting as many as 18 million Americans. 
   There are two types of sleep apnea: central and obstructive. Central sleep apnea, which is relatively rare, occurs when the brain fails to send the appropriate signals to the breathing muscles to initiate respirations, e.g., as a result of brain stem injury or damage. Mechanical ventilation is the only treatment available to ensure continued breathing. 
   Obstructive sleep apnea (OSA) is far more common. Normally, the muscles of the upper part of the throat keep the airway open to permit air flow into the lungs. When the muscles of the soft palate at the base of the tongue and the uvula (the small fleshy tissue hanging from the center of the back of the throat) relax and sag, the relaxed tissues may vibrate as air flows past the tissues during breathing, resulting in snoring. Snoring affects about half of men and 25 percent of women—most of whom are age 50 or older. 
   In more serious cases, the airway becomes blocked, making breathing labored and noisy, or even stopping it altogether. In a given night, the number of involuntary breathing pauses or “apneic events” may be as high as 20 to 30 or more per hour. These breathing pauses are almost always accompanied by snoring between apnea episodes, although not everyone who snores has this condition. Sleep apnea can also be characterized by choking sensations. 
   Lack of air intake into the lungs results in lower levels of oxygen and increased levels of carbon dioxide in the blood. The altered levels of oxygen and carbon dioxide alert the brain to resume breathing and cause arousal. The frequent interruptions of deep, restorative sleep often lead to early morning headaches, excessive daytime sleepiness, depression, irritability, and learning and memory difficulties. 
   The medical community has become aware of the increased incidence of heart attacks, hypertension and strokes in people with moderate or severe obstructive sleep apnea. It is estimated that up to 50 percent of sleep apnea patients have high blood pressure. 
   Upon an apneic event, the sleeping person is unable to continue normal respiratory function and the level of oxygen saturation in the blood is reduced. The brain will sense the condition and cause the sleeper to struggle and gasp for air. Breathing will then resume, often followed by continued apneic events. There are potentially damaging effects to the heart and blood vessels due to abrupt compensatory swings in blood pressure. Upon each event, the sleeping person will be partially aroused from sleep, resulting in a greatly reduced quality of sleep and associated daytime fatigue. 
   Although some apneic events are normal in all persons and mammals, the frequency of blockages will determine the seriousness of the disease and opportunity for health damage. When the incidence of blockage is frequent, corrective action should be taken. 
   The common method of diagnosing and determining the severity of sleep apnea is polysomnography. Polysomnography is a test that records a variety of body functions during sleep, such as the electrical activity of the brain, eye movement, heart rate, etc. 
   There are several methods and devices presently available for the treatment of snoring and OSA. There are oral appliances which are designed to displace the mandible (lower jaw) in an anterior (forward) direction by attaching to the upper and lower teeth. The intent is to displace the tongue in an anterior direction, increasing the size of the opening behind the tongue, resulting in an increased airway cross section. These devices have been only partially successful and are not tolerated by a significant percentage of the patients who have them fitted. 
   Another means of controlling snoring and sleep apnea is the use of a machine that delivers increased air pressure to the nose and mouth of the sleeper. These machines are described as CPAP (Continuous Positive Airway Pressure) machines. They entail wearing of a mask, headgear, and flexible hose which is attached to the air pump. A continuous flow of air at higher than ambient air pressure is forced into the persons&#39; airway, preventing closure of the soft tissue and the resultant apneic event. These devices have also been shown to reduce snoring but not necessarily prevent snoring entirely. 
   Although effective, the CPAP machine is not widely accepted by the patients. Discomfort, the sound of the air pump, claustrophobia and the stigma of being seen while wearing the mask, headgear, and hose have all been listed as reasons for not continuing use of the CPAP. 
   Several surgical approaches are used for these afflictions. One is a uvulopalatopharyngoplasty (UPPP) in which tissue at the posterior portion of the soft palate is removed, either by surgical excision or by use of a laser (so-called laser ablation). This is an invasive surgical procedure involving considerable pain in the recovery period, which can be lengthy. Side effects can involve escape of fluids upward into the nasal cavity and increased incidence of bothersome choking events. The long-term success of the UPPP in curing snoring and especially sleep apnea is only approximately 50%. 
   Other even more involved and invasive surgeries involve tongue reduction in which a section of the tongue is excised to reduce the tongue volume and maxillomandibular advancement in which the upper and lower jaws are severed and repositioned to create increased airway space will improve upon the UPPP success rates. Even more so than the UPPP, these procedures are painful, costly and require long recuperative periods. Absolute assurance of a successful outcome is lacking in these operations, also. 
   An office-based procedure—called the Somnoplasty® procedure (developed by Somnus Medical Technologies) can be performed using local anesthesia to treat upper-airway obstructions. The procedure uses controlled, low-power radiofrequency energy to create one or several submucosal volumetric lesions in the soft palate. Over a period of 6 to 8 weeks, the lesions are naturally resorbed, reducing tissue volume and stiffening remaining tissue in the desired area. 
   Other more intrusive treatments such as surgical interventions, i.e. glossectomy (reduction of the size of the tongue  34 ), genioglossal advancement (pulling the genioglossus muscle in an anterior direction to bring the tongue forward), maxillomandibular advancement (surgical alteration of a portion of the jaw bone and teeth plus the portion of the skull to which the upper teeth are attached) and uvulopalatopharyngoplasty—UPPP (the removal of a portion of the soft palate, either by surgical resection or laser ablation) all permanently modify the anatomy and can affect swallowing, speech and comfort in a negative manner. Other proposed devices, such as implantation of springs and other stiffening devices, can also have an undesired effect on daytime functions. 
   The need remains for simple, cost-effective devices and methods for reducing or preventing snoring and obstructive sleep apnea. 
   SUMMARY OF THE INVENTION 
   The invention provides systems and methods for selectively stabilizing tissue in the oral cavity. The systems and methods restrain movement of more mobile tissue within the oral cavity, e.g., the tongue, toward positions in which snoring and/or sleep apnea events can occur. 
   According to one aspect of the invention, the systems and methods include a first implant element sized and configured for implantation in a bone region within an oral cavity and a second implant element sized and configured for implantation in a tongue region within the oral cavity. The systems and methods also include a third implant element coupled to the first and second implant elements within the oral cavity. The third implant element is capable of applying force between the first and second implant elements such that the implant, in use, resists posterior movement of the tongue within the oral cavity. 
   In one embodiment, the first implant element is sized and configured for implantation in a mandible. 
   In one embodiment, the first implant element is sized and configured for implantation in a hyoid bone. 
   In one embodiment, the third implant element includes a component that applies force between the first and second implant elements in response to magnetic interaction with another component. 
   According to another aspect of the invention, the systems and methods, comprise a first implant element sized and configured for implantation in a bone region within an oral cavity and a second implant element sized and configured for implantation in a tongue region within the oral cavity. According to this aspect of the invention, a third implant element is coupled to the first and second implant elements within the oral cavity, which is capable of applying tension between the first and second implant elements such that the implant, in use, resists posterior movement of the tongue within the oral cavity. 
   In one embodiment, the first implant element is sized and configured for implantation in a mandible. 
   In one embodiment, the third implant element includes an elongated member that applies the tension. 
   According to another aspect of the invention, a method implants a first implant element in a bone region within an oral cavity and implants a second implant element in a tongue region within the oral cavity. The method resists posterior movement of the tongue within the oral cavity by coupling the first implant element to the second implant element within the oral cavity. 
   In one embodiment, the first implant element is implanted in a mandible. 
   In one embodiment, the first implant element is implanted in a hyoid bone. 
   According to another aspect of the invention, a method implants a first implant element in a bone region within an oral cavity and implants a second implant element in a tongue region within the oral cavity. The method resists posterior movement of the tongue within the oral cavity by placing into tension a third implant element between the second implant element and the first implant element within the oral cavity. 
   In one embodiment, the first implant element is implanted in a mandible. 
   In one embodiment, the third element comprises an elongated member placed into tension between the first and second implant elements. 
   Other features and advantages of the invention shall be apparent based upon the accompanying description, drawings, and claims. 

   
     DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an anatomical cross-section of a normal human nasal airway, oral cavity, and oropharynx. 
       FIG. 2  is a view similar to  FIG. 1 , illustrating occlusion of the oropharynx that occurs during obstructive sleep apnea. 
       FIG. 3A  is an anatomical cross-section of a human nasal airway showing the placement and interaction of primary and secondary magnets, both fixed to surface tissue, to effect anterior movement of the soft palate. 
       FIG. 3B  is an anatomical cross-section of a human nasal airway showing the placement and interaction of a primary magnet implanted in tissue and a secondary magnet affixed to surface tissue to effect anterior movement of the soft palate. 
       FIG. 4A  is an anatomical cross-section of a human nasal airway showing permanent primary magnet locations affixed to surface tissue of the soft palate and uvula. 
       FIG. 4B  is an anatomical cross-section of a human nasal airway showing permanent primary magnet locations implanted in tissue of the soft palate and uvula 
       FIG. 5A  is an anterior view of a human oral cavity showing placement of permanent primary magnets affixed to surface tissue of the soft palate and at the root of the uvula. 
       FIG. 5B  is an anterior view of a human oral cavity showing placement of permanent primary magnets implanted in tissue of the soft palate and at the root of the uvula. 
       FIG. 6A  is an oblique view of the primary magnet locations shown in  FIG. 5A . 
       FIG. 6B  is an oblique view of the primary magnet locations shown in  FIG. 5B . 
       FIG. 7  is an anatomical view of human oral cavity and illustrating the configuration and placement of primary magnets on the uvula and soft palate. 
       FIG. 8  is a perspective view of a primary magnet shown in  FIG. 7  and configured for attachment to the uvula. 
       FIG. 9  is a side view illustrating attachment of a primary magnet on the uvula using a stud and backing plate. 
       FIG. 10A  is a front view of a primary magnet configured for attachment to the soft palate. 
       FIG. 10B  is a side view of the magnet shown in  FIG. 10A . 
       FIG. 11  is a side view and illustrating the use of a stud to secure a magnet of the type shown in  FIGS. 10A and 10B  to a complementary backing pad. 
       FIG. 12A  is a top perspective view of a soft pad oral appliance device with flexible, movable mounting stem and secondary magnet at the distal end which embodies features of the invention. 
       FIG. 12B  is a bottom perspective view of the soft pad oral appliance device shown in  FIG. 12A . 
       FIG. 13  is a side section view of the oral appliance shown in  FIG. 12A . 
       FIG. 14  is an anatomical cross-section of a human upper airway showing the use of a positioning tool to place the oral appliance of  FIGS. 7 and 8  within the oral cavity. 
       FIG. 15  is a perspective view of the positioning tool shown in  FIG. 14 . 
       FIG. 16  is an anatomical view of a human oral cavity illustrating the placement of an alternative embodiment of an oral appliance embodying features of the invention within the oral cavity. 
       FIG. 17  is a bottom view of the oral appliance shown in  FIG. 16 . 
       FIG. 18  is a perspective view of the oral appliance shown in  FIG. 16 . 
       FIG. 19  is a perspective view of an alternative embodiment of the oral appliance shown in  FIG. 18 . 
       FIG. 20  is an anatomical cross-section of a normal human nasal airway, oral cavity, and oropharynx showing the placement of a primary magnet within the tongue to effect anterior movement of the tongue. 
       FIG. 21  is a top view of the tongue shown in  FIG. 20  and illustrating the placement of primary magnets in the opposing lateral margins of the tongue to effect anterior movement of the tongue. 
       FIG. 22  is a perspective view of an oral appliance embodying features of the invention. 
       FIG. 23  is an anatomical front view of a human oral cavity illustrating the placement of the appliance of  FIG. 22  over the bottom teeth. 
       FIG. 24  is a perspective view of an oral appliance embodying features of the invention. 
       FIG. 25  is an anatomical front view of a human oral cavity illustrating the placement of the appliance of  FIG. 24  over the upper teeth. 
       FIG. 26  is an anatomical cross-section of a human nasal airway showing the placement of the appliances of  FIGS. 22 and 24  within the oral cavity. 
       FIG. 27  is an anatomical cross-section of a human nasal airway showing an alternative embodiment of the oral appliance shown in  FIG. 24 . 
       FIG. 28  is an anatomical cross-section of a human upper airway illustrating an alternative embodiment of the invention in which a primary magnet is attached to the epiglottis and a secondary magnet is carried by an external neck collar. 
       FIG. 29  is a perspective view of an alternative embodiment of the collar shown in  FIG. 28 . 
       FIG. 30  is an anatomical cross-section of a human upper airway illustrating an alternative embodiment of the invention in which a primary magnet is carried by a fulcrum attached to the hyoid bone and a secondary magnet is carried by an external neck collar. 
       FIG. 31  is an anatomical cross-section of a human upper airway illustrating an alternative embodiment of the fulcrum shown in  FIG. 30  and its placement in tissue in front of and above the hyoid bone. 
       FIG. 32  is an anatomical cross-section of a human upper airway illustrating an alternative embodiment of the invention in which a primary magnet is carried by a device implanted into the mandible and a secondary magnet is carried by an external neck collar. 
       FIG. 33  is a side view of an alternative embodiment of the device shown in  FIG. 32 . 
       FIG. 34  is an anatomical cross-section of a human upper airway illustrating an alternative embodiment of the invention in which a primary magnet is carried by a device implanted into the mandible and a secondary magnet is carried by an external neck collar. 
       FIG. 35  is a perspective view of the device of  FIG. 34  and illustrating upward movement of the lifting arm in response to anterior movement of the pull wire. 
       FIG. 36  is a cross-sectional view of the device of  FIG. 35 . 
       FIG. 37  is a view similar to  FIG. 36  and illustrating the upward and forward movement of the lifting arm in response to the magnet being pulled in a downward direction. 
       FIG. 38  is a perspective view of an oral appliance intended for placement within the oral cavity and including a suction source to affect anterior movement of the soft palate and/or uvula. 
       FIG. 39  is a top view of the suction source that is carried by the appliance shown in  FIG. 38 . 
       FIGS. 40A and 40B  are side section views of the suction source shown in  FIG. 39 , being operated during use to affect anterior movement of the soft palate and/or uvula. 
       FIG. 41  is an anatomical view of a human oral cavity illustrating the placement of the oral appliance shown in  FIG. 38  to affect anterior movement of the soft palate and/or uvula. 
       FIG. 42  is a perspective view of an oral appliance intended for placement on the bottom teeth within the oral cavity and including a suction source to affect anterior movement of the tongue. 
       FIG. 43  is an anatomical view of a human oral cavity illustrating the placement of the oral appliance shown in  FIG. 42  to affect anterior movement of the tongue. 
   

   DETAILED DESCRIPTION 
   Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structure. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims. 
   I. Anatomy of the Upper Respiratory System 
     FIG. 1  illustrates the normal anatomy of the human upper respiratory system, which communicates with the trachea  10  and the lower respiratory system through the larynx  12 . In humans, the pharynx is divided into nasal, oral, and laryngeal portions. The nasopharynx  14  lies posterior to the nasal cavity  16 . The oropharynx  18  communicates with the nasopharynx  14  superiorly, the oral cavity (mouth)  20  anteriorly, and the laryngopharynx  22  inferiorly. The laryngopharynx  22  lies posterior to the larynx  12  and serves as the entrance to the esophagus  24 . 
   The upper part of the oral cavity  20  is the palate  26 , and it separates the oral cavity  20  from the nasal cavity  16 . The anterior two-thirds of the palate  26  is the bony hard palate  28 . The movable posterior third of the palate  26 , made up of muscle and aponeurosis, is known as the soft palate  30 . The soft palate  30  is suspended from the posterior border of the hard palate  28  and extends posteroinferiorly as a curved free margin from which hangs a conical process, the uvula  32 . The tongue  34  is located over the floor of the oral cavity  20 . The epiglottis  33  is a thin leaf-shaped structure immediately posterior to the base of the tongue  34 . The epiglottis  33  covers the entrance of the larynx  12  when an individual swallows, thereby preventing food or liquids from entering the airway. These structures are all interrelated in the functions of breathing, swallowing and speech. 
   With reference to  FIG. 2 , during sleep, the soft palate  30  and uvula  32 , being unsupported by bone or cartilage, can droop into the airway and vibrate, resulting in loud snoring. A similar situation exists in which the tongue  34  can become relaxed and move in a posterior direction, partially or fully obstructing the airway. This condition can cause a hypopnea, in which the airway is partially obstructed, making breathing more difficult, or apnea, in which the airway is completely obstructed. Sleep apnea, and to a lesser degree, hypopnea can have extremely serious health consequences. 
   As  FIG. 2  illustrates, the soft palate  30  and uvula  32  may actually come in contact with the posterior wall of the oropharynx  18 . In addition, the back of the tongue  34  may come to lie near the posterior wall of the oropharynx  18 . Because of the narrowed space, the velocity of the air passing through the airway will be affected and the soft palate  30  can vibrate and/or flutter during respiration, emitting a loud sound (snoring). This can happen with or without the tongue  34  being in the rearward position shown in  FIG. 2 . 
   The tongue  34  can also fall toward the rear of the mouth  20  and partially or fully obstruct the airway. At the end of exhalation and the beginning of inhalation is the point at which the tongue  34  and/or soft palate  30  can stop the airflow within the airway, resulting in an apneic event. If the airway is partially obstructed, an hypopnea can occur. 
   Therefore, as indicated by arrows in  FIG. 2 , the desirable forces and tissue location are in an anterior direction. If the soft palate  30  and the tongue  34  are moved and retained as shown during sleep, the airway will remain unrestricted and the tendency for the soft palate  30  to vibrate or flutter will be reduced or eliminated entirely. 
   II. System Overview (Primary Magnet Configured for Anterior Movement of Soft Palate and/or Uvula) 
     FIGS. 3A and 3B  illustrate alternative embodiments of a system for treating sleep-related breathing disorders such as snoring, upper airway resistance syndrome and obstructive sleep apnea. The system employs at least one primary magnet  36  and at least one secondary magnet  38 . Together, the magnets  36  and  38  serve to position, stabilize and maintain a preferred orientation of tissue in an oral cavity and airway in both humans and animals. By moving and stabilizing tissue in a desired location and shape, the system mediates or prevents the obstruction of the upper airway that results in sleep-related breathing disorders. Still, as will be described, the system achieves these results without permanent modification of the anatomy. 
   An object that exhibits magnetic properties (i.e., magnetism) is called a magnet. Magnetism is a force of attraction or repulsion between various substances, especially those made of iron and certain other metals, ultimately due to the motion of electric charges. Every magnet has a magnetic field, which is a region around the magnet in which the magnetic effects are observed. In the illustrated embodiment, the primary and secondary magnets  36  and  38  are desirably permanent magnets, i.e., they maintain an essentially constant magnetic field over time. 
   The magnets  36  and  38  possess poles of opposite polarity. The poles are centers where magnetic attraction is strongest. If the magnet is free to turn, one pole will point north, and is thus called a North pole, and the opposite pole is likewise called a South pole. According to physical laws, poles of like polarity (North-North or South-South) repel each other with a magnetic force. On the other hand, poles of unlike polarity (North-South or South-North) attract each other with a magnetic force. The force of magnetic attraction or repulsion depends on the strength of the magnets and the distance between the poles. 
   In the alternative embodiments illustrated in  FIGS. 3A and 3B , the primary and secondary magnets  36  and  38  are mutually oriented so that the force of magnetic attraction draws the primary magnet  36  toward the secondary magnet  38 . That is, the primary magnet  36  is of opposite polarity from the secondary magnet  38 , e.g., the primary magnet  36  is of North polarity and the secondary magnet  38  is of South polarity, or vice versa. In this Specification, such an orientation of magnetic poles is called “complementary.” 
   In this arrangement, the secondary magnet  38  is intended to be carried in or by relatively immobile tissue, or at least mounted more securely than the primary magnet  36 . The primary magnet  36  is intended to be carried in or by mobile tissue. Thus, as the more mobile primary magnet  36  is drawn toward the less mobile secondary magnet  38 , a desired movement of tissue occurs. 
   It should be appreciated that either magnet  36  or  38  may exert a magnetic force on a material that is not magnetized. Therefore, one of the magnets  36  or  38  can be replaced by a material, e.g., ferrous plate, on which the remaining magnet  36  or  38  is able to exert an attractive magnetic force. Of course, a ferrous plate could not exert a repelling force without itself being magnetized. The terms “primary magnet(s)” or “secondary magnet(s)” as used in this specification are therefore not limited to an object that exhibits magnetic properties (i.e., an object that is magnetized), but also encompass an object made of a material that is not itself magnetized but which is attracted to another object that is magnetized. Still, use of the terms requires that at least one of the “primary magnet(s)” or “secondary magnet(s)” comprise an object that is magnetized. 
   In  FIGS. 3A and 3B , the primary magnet  36  is carried by more mobile tissue of the soft palate  30 , e.g., at the root of the uvula  32 . In  FIG. 3A , the primary magnet  36  is attached to surface tissue at the root of the uvula  32 . In  FIG. 3B , the primary magnet  36  is implanted in tissue at the root of the uvula  32 . In either situation, the portion(s) of the primary magnet  36  contacting tissue (either surface or subsurface) desirably includes a biocompatible coating to prevent interaction between the magnet and tissues/fluids of the body. The secondary magnet  38  is carried by an oral appliance magnet holder  40 , which is carried by less mobile tissue (i.e., the upper teeth) along the roof of the mouth. Technical features of the holder  40  will be described in greater detail later. 
   Arranged in a complementary manner, the less mobile secondary magnet  38  acts upon the more mobile primary magnet  36  to draw the primary magnet  36 , and, with it, the mobile tissue of the soft palate  30 , in an anterior direction (depicted by phantom lines in  FIG. 3A  and  FIG. 3B ) to prevent obstruction of the airway. 
   As will be demonstrated, the primary and secondary magnets  36  and  38  can be sized, configured, and placed in a variety of arrangements to effect the desired positioning of tissue. Depending upon the degree of flexibility or firmness of the palate  26 , the physician may attach one or several primary magnets  36  to the soft palate  30  and variations in the oral appliance  40  can accommodate the variation in the number and position of the magnets  36 . 
   As will be discussed later, in alternative arrangements, the primary and secondary magnets  36  and  38  may be mutually oriented so that the force of magnetic attraction repels the magnets  36  and  38  away from each other. That is, the primary magnet  36  is of the same polarity from the secondary magnet  38 , e.g., the primary and secondary magnets  36  and  38  are both of North polarity or South polarity. In this Specification, such an orientation of magnetic poles is called “non-complementary.” In this arrangement, the secondary magnet  38  is still intended to be carried in or by relatively immobile tissue, while the primary magnet  36  is intended to be carried in or by mobile tissue. Thus, the more mobile primary magnet  36  is repelled away from the less mobile secondary magnet  38 , and a desired movement of tissue occurs. 
   A. The Primary Magnet(s) 
     FIGS. 4A and 4B  show alternatively implementation of a representative embodiment, in which two primary magnets  36  are attached to the anterior surface of the soft palate  30  and root of the uvula  32  respectively. In  FIG. 4A , the magnets  36  are removably attached to exterior tissue using studs  42  that are fitted into pierced holes  44  in the tissue and are secured by a retaining lock device, e.g., a backing plate  46  on the posterior surface of the soft palate  30 . The backing plate  46  is desirably made of silicone or a similar biocompatible elastomeric material. Alternatively, as seen in  FIG. 4B  and  FIG. 14 , the primary magnets  36  may be implanted within the soft palate  30 . The portion(s) of the primary magnet  36  contacting tissue (either surface or subsurface) desirably includes a biocompatible coating to prevent interaction between the magnet and tissues/fluids of the body. 
   FIGS.  5 A/ 5 B and  6 A/ 6 B show alternative arrangements of primary magnets  36  in the soft palate  30 . In this arrangement, a primary magnet  36 A is attached to the soft palate  30  at approximately the base of the uvula  32 . A pair of additional primary magnets  36 B are positioned in the soft palate  30  anterior to and radially from the first primary magnet  36 A in a triangular configuration. In  FIGS. 5A and 6A , the primary magnets  36  are attached to surface tissue at the base of the uvula  32 . In  FIG. 5B and 6B , the primary magnets  36  are implanted in tissue at the base of the uvula  32 . As before stated, the portions of the primary magnets  36  contacting tissue (either surface or subsurface) desirably includes a biocompatible coating to prevent interaction between the magnet and tissues/fluids of the body. 
     FIGS. 7 to 11  detail representative embodiments of soft palate primary magnets  36 A and  36 B.  FIG. 7  shows a primary magnet  36 A configured for attachment to the uvula  32  and primary magnets  36 B configured for attachment to the soft palate  30  adjacent the uvula  32 . 
   As best seen in  FIG. 8 , the front side  48  and the back side  50  of the magnet  36 A provide a concave, or sectorial, configuration, to approximate the contour of the anterior surface of the uvula. A screw stud hole  44 A permits passage of the stud  42  to allow attachment of the magnet  36 A to the uvula  32 . The edges of the magnet  36 A are desirably rounded or radiused, to prevent irritation of surrounding tissue. This provides increased comfort to the individual. 
   As seen in  FIG. 9 , the magnet  36 A is placed on the anterior surface of the uvula  32 . A stud  42  is passed through the screw stud hole  44 A and the magnet  36 A is secured in place by the backing plate  46 A. 
   As  FIGS. 10A and 10B  show, the soft palate primary magnets  36 B have a bowed configuration to approximate the contour of the arch of the soft palate  30 , e.g., kidney bean shape. Similar to primary magnet  36 A, rounded or radiused edges are provided to prevent irritation of surrounding tissue. 
   With reference to  FIG. 11 , a conformal backing plate  46 B serves to secure attachment of the magnet  36 B to the soft palate  30 . In the arrangement shown in  FIG. 11 , the plate  46 B includes a pair of pins  54  (left and right), each pin having a bore  56  to receive and secure a stud  42 , e.g., by threaded engagement. The magnet  36 B includes a pair of screw stud holes  52 B (left and right) that register with the pins  54 . The holes  52 B are desirably tapered and configured to receive the pins  54  and permit passage of studs  42  to secure attachment of the magnet  36 B. 
   B. Oral Appliances for Removably Mounting the Secondary Magnet in the Oral Cavity 
   1. First Embodiment 
   Referring now to  FIGS. 12A ,  12 B, and  13 , the system includes an oral appliance  40  to carry the secondary magnet  38  within the oral cavity  20 . Desirably, the oral appliance  40  is configured for convenient temporary placement into and removal from the oral cavity  20 . 
   As before explained, the secondary magnet  38  is complementary to the primary magnet  36 , i.e., the primary and secondary magnets  36  and  38  are of opposite polarity. 
   As shown in  FIGS. 12A and 12B , the appliance  40  comprises a base pad  58  and a support stem  60 . The support stem  60  carries one or more secondary magnets  38  on its far end. As seen in  FIG. 12B , the bottom surface of the appliance  40  includes positioning holes  62 , the function of which will be described later. 
   The bottom surface also carries a slidable knob  64 , which forms the near end of the support stem  60 . As  FIG. 13  shows, the knob  64  works against a spring  68  within the base pad  58 . The spring  68  biases the support stem  60  and secondary magnet  38  toward an anterior position in the oral cavity  20 . The spring  68  nevertheless accommodates transitory movement of the secondary magnet  38  toward a more posterior direction. More particularly, the spring  68  allows the secondary magnet  38  to follow transitory anterior-posterior movement of the more mobile primary magnet  36 , e.g., during swallowing, while still urging the primary magnet  36 , and, with it, the mobile tissue attached to it, toward a desired anterior position. 
   In use, as shown by an arrow in  FIG. 3 , the knob  64  can be manipulated by the wearer to slide the secondary magnet  38  toward the rear of the mouth  20 , and thus toward the primary magnet(s)  36  affixed to the soft palate  30 . As attraction between the magnets  36  and  38  occurs, the wearer can release the knob  64 . When released, the spring  68  urges the stem  60  (and secondary magnet  38 ) toward an anterior position within the mouth  20 . The tissue of the soft palate  30  and uvula  32  are thereby urged forward toward a desired anterior position, as depicted by phantom lines in  FIG. 3 , to prevent the tissue of the soft palate  30  from falling back into the airway. 
   The spring  68  is designed to place a light pulling force in the range of 2 to 50 grams on the primary magnet(s)  36  affixed to the soft palate  30 . It is believed that these low pulling forces are sufficient. The light pulling forces further provide comfort to the wearer and avoid irritation to the tissue. 
   The base  58  of the appliance  40  can be constructed of a resilient, soft elastomeric material such as silicon rubber, or may alternatively be made of a closed-cell polymeric foam. These soft materials allow the body of the device to conform to the roof of the mouth  20 , which can varies greatly among individuals. The base  58  can be positioned within the oral cavity  20  and attached to the roof of the mouth  20  using a high-tack adhesive compatible with the oral cavity  20 , such as that used to secure dentures to gums. 
   Desirably, the interior surface of the bore  70  (see  FIG. 13 ), in which the stem  60  and the spring  68  are positioned, is injection molded of a rigid, thermoplastic material such as ABS, acetal, or polypropylene to provide smooth sliding action for the stem  60 . The appliance  40  may be overmolded by the soft material of the base pad  58 , or the appliance  40  may be inserted and bonded into a recess in the base pad  58 . This hybrid structure for the appliance  40  provides dimensional integrity needed to prevent binding of the moving parts, which might result from having the bore  70  located directly in the compliant material, while nevertheless allowing the base  58  to be soft and conformable enough to fit a wide variation in shape and contour of the roof of the mouth  20 . 
   In use, the opposing pole magnets  36  and  38  may make physical contact with each other. Alternatively, the opposing pole magnets  36  and  38  may be positioned so that they are magnetically attracted to one another without physical contact. 
   There may be one or more primary magnets  36  attached to the uvula  32  and/or soft palate  30 , as previously described and as shown in  FIGS. 4 and 5 . 
   The appliance  40  is desirably configured for easy insertion into and removal from the oral cavity  20  by the wearer. Thus, the appliance  40  may be used only during sleep and removed upon awakening. Removal of the appliance  40  during waking hours prevents any interference with swallowing, speech, or other routine activities. 
   A physician can initially fit the appliance  40  to an individual&#39;s mouth  20 . The physician visually determines the appropriate position within the mouth  20  to properly pull the soft palate  30  and uvula  32  in an anterior direction and to the desired degree. To aid the individual to subsequently position the appliance  40  within the mouth  20 , a positioning tool  72  is desirably supplied with the appliance  40 . 
     FIGS. 14 and 15  show a representative embodiment for a positioning tool  72  suitable for this purpose. The tool  72  desirably includes a handle  74 . The handle  74  can be molded integrally with a carrier back  76 , which extends for the entire length of the tool  72 . 
   A center pointer  78  is molded as a part of a slider  80 . The fore and aft position of the slider  80  is desirably fixed by the physician when customizing the tool  72  to the individual, as represented by arrow  81  in  FIG. 15 . A locking tab  82  holds an interior locking pin  84 . When the physician sets the slider  80  in the desired location, the locking tab  82  can be withdrawn, allowing the internal locking pin  84  to engage openings  86  in the carrier back  76 . The slider  80  is thereby permanently set by the physician in the desired position customized for the individual. 
   Notches  88  and upright fingers  90  form a receiver for the lateral incisors, to provide a positioning feature that allows the tool  72  to accurately place the base  58  of the appliance  40  in the roof of the mouth  20 . A rotatable member  92  pivots about a pivot pin  94  and is subject to a light friction to prevent undesirable rotation. 
   The tool  72  further includes a pair of positioning pins  96 , which extend from the rotatable member  92 . The pins  96  register with and enter the positioning holes  62  on the appliance  40 , as previously described. The patient places the base  58  on the tool  72  by pressing the base  58  onto the pins  96  to engage the positioning holes  62  with the pins  96 . The elastic nature of the compliant material in the base  58 , along with a hole diameter slightly smaller than the diameter of the standing pins  96 , causes the base  58  of the appliance  40  to be frictionally held on the rotatable member  92 . 
   Once the appliance  40  is fitted to the positioning tool  72 , the patient applies a prescribed amount of adhesive (not shown) to the top surface of the base  58 . Manipulating the positioning tool  72  like a tongue depressor, the individual positions the tool  72  in the oral cavity  20  (see  FIG. 14 ). 
   While standing in front of mirror, the individual aligns the pointer  78  with the interdental space between the two upper incisors. The individual also brings the notches  88  into contact with the occlusal surface of the lateral incisors, with the upright fingers  90  pressing against the anterior surface of the upper teeth(because the physician has previously adjusted the center pointer  78  to the appropriate fore and aft position, as previously described, it is not necessary for the individual to make any further adjustments). 
   With the handle  74  held horizontally (depicted in solid lines in  FIG. 14 ), the individual holds the positioning tool  72  against the upper teeth. The individual pivots the exposed handle end  74  of the tool  72  downward (as depicted by the arrow and phantom lines in  FIG. 14 ). The far end  98  of the appliance  40  swings in an upward arc toward the roof of the mouth  20 , as represented by phantom lines in  FIG. 14 . As the appliance  40  moves upward, the stem  60  of the appliance  40  makes contact with the hard palate  28  at a desired point  100 . This causes the rotatable member  92  to swing (depicted by arrow  99  in  FIG. 15 ) bringing the top surface of the base  58  (with the dental adhesive material) into an orientation that is parallel to the roof of the mouth  20 , and in a position selected by the physician when the appliance  40  was originally fitted. 
   After holding a light pressure upward for a short time period, e.g., approximately 10 seconds, the individual pulls the positioning tool  72  downward to release it from the base  58 , leaving the appliance  40  affixed to the roof of the mouth  20  in the desired position. Upon removing the tool  72 , the individual can use a thumb or finger to press the base  58  into intimate contact with roof of the mouth  20  and set the bond. 
   Referring again to  FIG. 3 , the patient then places a finger on the knob  64  to move the knob  64  as depicted by an arrow in  FIG. 3  toward the back of the mouth  20  to bring the primary magnet(s)  36  into attraction with the secondary magnet(s)  38 , thereby pulling the soft palate  30  and uvula  32  into a forward, stabilized position. 
   To remove the appliance  40 , the patient uses a fingertip to peel the flexible base  58  away from the roof of the mouth  20 . In one embodiment (see  FIGS. 12A and 12B ), the anterior end  101  of the appliance  40  can include a groove or chamfer  102  to facilitate peeling the base pad  58  away from the roof of the mouth  20 , as also shown in  FIG. 14 . The remaining adhesive can be removed by brushing with a toothbrush. To reuse the appliance  40 , the patient peals off the remaining adhesive attached to the base  58  by using a fingertip to roll the adhesive off of the top surface of the base  58 . 
   The appliance  40  may, alternatively, be of a modular design, allowing the soft compliant base  58  to be a disposable component into which the tool  72  may be placed and withdrawn for re-use the next night. The disposable base  58  may contain a pressure sensitive adhesive to eliminate the need to use and apply a liquid adhesive. 
   2. Second Embodiment 
     FIGS. 16 to 18  show another representative embodiment of an appliance  104  that can be releasably mounted in the oral cavity  20 , to hold one or more secondary magnets  38  in alignment with one or more primary magnets carried by the soft palate and/or uvula. 
   In this arrangement, secondary magnets  38 C and  38 D are mounted on a stem portion  106  having a knob  108  at the anterior end  110  of the appliance  104 . The secondary magnet  38 C is positioned at the posterior end  112  of the stem  106  and is complementary to primary magnet  36 C attached to the uvula  32  (see  FIG. 16 ). Desirably, a pair of secondary magnets  38 D also extend radially from the stem  106 , just posterior to the secondary magnet  38 C. The secondary magnets  38 D align with and complement the primary magnets  36 D attached to the soft palate  30 . 
   Spring wires  114  extend radially from the stem  106 . In this embodiment, the appliance  104  is held in place by use of an elastic band  116 . In use, the band  116  is stretched around the outer faces of the upper teeth. The appliance  104  can also be anchored at the posterior surface of the molars by a pair of hooks  118  which couple with the spring wires  114 . 
   Indexing locators  120  can be provided to permit the position of the hooks  118  to be adjustable posteriorly and anteriorly for proper fit. The indexing locators  120  may be adjusted by the physician to fit into the interdental spaces between the molars and then locked in place to provide a repeatable positioning of the appliance  104 . As best seen in  FIG. 18 , a series of holes  122  are desirably provided for easy adjustment of the locators  120 . 
   When in place, the appliance  104  is positioned to permit an attraction between the opposing magnetic poles and pull the tissue of the soft palate  30  and uvula  32  in an anterior direction, as depicted by arrows in  FIG. 16 . 
   As shown in  FIG. 19 , the hooks  118  may be replaced by molded trays  124  into which the patient may place a small amount of dental adhesive (not shown). In this embodiment, the band  116  is desirably a non elastic material such as a nylon with a soft covering, preferably a silicone rubber. The patient slips the band  116  of the appliance  104  over the front surface of the upper teeth and with the dental adhesive already in the molded trays  124 , presses the trays  124  upward into intimate contact with the upper rear molars. 
   It should be appreciated that the oral appliance for holding one or more secondary magnets in alignment with one or more primary magnets, carried by the soft palate and/or uvula, can be custom formed to the individual&#39;s hard palate. This arrangement would make possible an established and familiar way of placing a dental/oral appliance in the mouth. 
   3. Third Embodiment 
     FIGS. 24 and 25  show another alternative embodiment of an oral appliance  142  that can be releasably mounted in the oral cavity  20 , to hold one or more secondary magnets  38  in alignment with one or more primary magnets carried by the soft palate and/or uvula. 
   In this embodiment, the appliance  142  comprises a generally U-shaped body  144 . One or more secondary magnets  38  are carried by a bar  146  extending from slots  148  on the medial surface of the body  144 . 
   The body  144  is a generally hollow body having an open top  136  and open ends  138 , sized and configured to rest on the upper teeth, as seen in  FIG. 25 . Placement of the appliance  142  on the upper teeth results in attractive magnetic forces (represented by an arrow in  FIG. 25 ) between the primary and secondary magnets  36  and  38 , drawing the primary magnet  36  toward the secondary magnet  38 , thereby pulling the uvula  32  and soft palate  30  into a forward, stabilized position. 
   The bar  146  can be configured for adjustment by anterior or posterior movement, as represented by phantom lines in  FIG. 24 . This adjustment permits the secondary magnet  38  to be positioned properly in relation to the primary magnet  36  to effect the desired movement of tissue. In the illustrated embodiment, the slots  148  have a ratcheted surface  150  on which the bar  146  may be moved in fore and aft directions. Of course, other mechanisms may be used to provide such movement. 
   III. Another System Overview (Primary Magnet Configured for Anterior Movement of the Tongue) 
   As previously discussed, the tongue  34  is frequently the primary cause of apneic events. During sleep, tongue muscles can relax and allow the tongue  34  to move in a posterior direction and contact the pharyngeal wall, occluding the oropharynx  18  (see  FIG. 1 ). If the tongue  34  is in the position described at the point of completing the exhalation cycle, it can act as a check valve, preventing inhalation. 
     FIGS. 20 to 23  illustrate one embodiment of another system for treating sleep-related breathing disorders such as snoring, upper airway resistance syndrome and obstructive sleep apnea. The system includes at least one primary magnet  36 ′ implanted or otherwise affixed to the tongue  34 , which can be used in association with a complementary secondary magnet  38 ′ to position, stabilize and maintain the tongue in a preferred orientation in the oral cavity and airway, in both humans and animals. By moving and stabilizing the tongue in a desired location, the system mediates or prevents the obstruction of the upper airway that results in sleep-related breathing disorders. 
   In the embodiment illustrated in  FIGS. 20 to 23 , the primary magnet  36 ′ is of opposite polarity from the secondary magnet  38 ′, e.g., the North pole of the primary magnet  36  is oriented to face the South pole of the secondary magnet  38 , or vice versa. The primary and secondary magnets  36 ′ and  38 ′ are therefore complementary, i.e., they are mutually oriented so that the force of magnetic attraction draws the primary magnet  36 ′ toward the secondary magnet  38 ′. 
   As previously described, the secondary magnet  38 ′ is intended to be carried in or by relatively immobile tissue, or at least mounted more securely than the primary magnet  36 ′. The primary magnet  36  is intended to be carried in or by more mobile tissue. Thus, as the more mobile primary magnet  36 ′ is drawn toward the less mobile secondary magnet  38 ′, a desired movement of tissue occurs. 
   It should again be appreciated that either magnet  36 ′ or  38 ′ may exert a magnetic force on a material that is not magnetized. Therefore, one of the magnets  36 ′ or  38 ′ can be replaced by a material, e.g., ferrous plate, on which the remaining magnet  36 ′ or  38 ′ is able to exert an attractive magnetic force. Of course, a ferrous plate could not exert a repelling force without being magnetized. 
   In  FIGS. 20 to 23 , the primary magnet  36 ′ is carried by the more mobile tissue of the tongue  34 . The secondary magnet  38 ′ is carried by an oral appliance  126 , which is releasably mounted to less mobile tissue (i.e., the lower teeth) along the floor of the mouth. Technical features of the holder  126  will be described in greater detail later. 
   Arranged in a complementary manner, the less mobile secondary magnet  38 ′ acts upon the more mobile primary magnet  36 ′ to draw the primary magnet  36 , and, with it, the tongue  34 , in an anterior direction (depicted by arrows in  FIG. 23 ) to prevent obstruction of the airway. 
   A. Primary Magnet(s) 
     FIGS. 20 and 21  show a representative embodiment in which two primary magnets  36 ′ are implanted in the opposing lateral margins of the tongue  34 . The secondary magnet  38 ′ is carried by an oral appliance  126  and interacts with the primary magnet  36 ′ to effect anterior movement of the tongue  34  (see, e.g.,  FIG. 22 ). Sutures, bands or strips  128  can be implanted into the posterior of the tongue  34  and fastened to the magnets  36 ′ to help pull the tongue  34  forward and distribute the forces of magnetic attraction more evenly within the tongue  34 . 
   The magnets  36 ′ can be coated with a fibrous or textured polymer layer to promote in growth of tissue into the coating. Tissue in growth will help to anchor the magnets  36 ′ and reduce the possibility of migration of the magnets  36 ′ caused by pulling forces. 
   B. Oral Appliances for Removably Mounting Secondary Magnet(s) within the Oral Cavity 
     FIGS. 22 and 23  illustrate one embodiment of an oral appliance  126  that can be releasably mounted in the oral cavity  20 , to hold one or more secondary magnets  38 ′ in alignment with one or more primary magnets  36 ′ implanted within the tongue  34 , to affect anterior movement of the tongue  34 . The oral appliance  126  can be variously configured to permit conduction of magnet forces between the primary and secondary magnets  36 ′ and  38 ′. 
   Like the appliance  40 , the appliance  126  is desirably configured for easy insertion and removal, so that it may be used only during sleep and removed upon awakening. Removal of the appliance  40  during waking hours prevents any interference with swallowing, speech, or other routine activities. 
   The appliance  126  comprises a generally U-shaped body  130  and a pair of secondary magnets  38 ′ (right and left) carried by arms  132  extending from connectors  134  on the medial surface of the body  130 . 
   The body  130  is a generally hollow body having an open bottom  136  and open ends  138 , sized and configured to rest on the bottom teeth, as seen in  FIG. 23 . Placement of the appliance  126  on the bottom teeth aligns with secondary magnets  36 ′ with the primary magnets  34 ′. This results in attractive magnetic forces (represented by arrows in  FIG. 23 ) between the primary and secondary magnets  36 ′ and  38 ′. The complementary magnets  36 ′ draw primary magnets  36 ′ toward secondary magnet  38 ′, thereby pulling the tongue  34  into a forward, stabilized position. 
   The arms  132  can be configured for adjustment by anterior or posterior movement. This adjustment permits the secondary magnets  38 ′ to be positioned properly in relation to the primary magnets  36 ′ to effect the desired movement of tissue. In the illustrated embodiment, the connector  134  has a ratcheted surface  140  on which the arm  132  may be moved in anterior and posterior directions. Of course, other mechanisms can be used to provide this adjustment. 
     FIG. 26  illustrates the use of the upper appliance  142  previously discussed and shown in  FIGS. 24 and 25 ) in combination with the lower appliance  126 . As  FIG. 26  shows, the upper appliance  142  acts to effect anterior movement (depicted by an arrow) of the soft palate  30  and uvula  32 . The lower appliance  126  acts to effect anterior movement (depicted by an arrow) of the tongue  34 . In this arrangement, the appliances  126  and  142  cooperate to maintain a desired position of the soft palate  30 , uvula  32 , and tongue  34  to mediate or prevent obstruction of the upper airway that results in sleep-related breathing disorders. 
   In another alternative embodiment, shown in  FIG. 27 , a single appliance  152  carries both secondary magnets  38  and  38 ′. The appliance  152  is configured for placement over the upper teeth and is similar to the embodiment of the appliance  142  shown in  FIGS. 24 and 25 . However, a pair of secondary magnets  38 ′ (right and left) are carried by arms  132  extending from connectors  134  on the medial surface of a U-shaped body  152  similar to the embodiment shown in  FIGS. 23 and 24 . Thus, in this arrangement, a single appliance serves to effect movement of the soft palate  30 , uvula  32 , and tongue  34  to mediate obstruction of the upper airway that results in sleep-related breathing disorders. 
   IV. Another System Overview (Primary Magnet Attached to Epiglottis with External Secondary Magnet) 
     FIGS. 28 and 29  illustrate one embodiment of another system for treating sleep-related breathing disorders such as snoring, upper airway resistance syndrome and obstructive sleep apnea. The system includes at least one primary magnet  156  affixed to the epiglottis  33 , which is used in association with a complementary secondary magnet  38  to position, stabilize and maintain the tongue in a preferred orientation in the oral cavity and airway in both humans and animals. The complementary magnetic forces serve to support and move the tongue  34  forward to prevent contact between the back of the tongue  34  and the pharyngeal wall, thus preventing occlusion of the airway. 
   As previously described, the secondary magnet  38 ′ is intended to be carried in or by relatively immobile tissue, or at least mounted more securely than the primary magnet  36 ′. In the illustrated embodiment, the secondary magnet  36  is carried by a collar  158  worn externally about the neck. The primary magnet  156  is intended to be carried in or by mobile tissue. In the illustrated embodiment, the primary magnet  156  is affixed to the epiglottis. Thus, as the more mobile primary magnet  156  is drawn toward the less mobile secondary magnet  38 , a desired movement of tissue occurs. 
   A. Primary Magnet(s) 
   In the illustrated embodiment, the primary magnet  156  comprises a ferrous plate  156  that is attached to the anterior surface of the epiglottis  33  and secured by a stud  42  and a flexible backing  46 . As previously described, the ferrous plate  156  may alternatively be a magnet of metallic or rare earth composition. Thus, the plate  156  functions similar to primary magnet  36  previously described. 
   Multiple studs  42  may be used to affix the plate  156  (or magnet  36 ) to the epiglottis  33 . Alternatively, the ferrous plate  156  (or magnet  36 ) may be implanted within tissue of the epiglottis  33 . 
   The backing  46  is desirably thin, e.g., approximately 1 mm, and tapered at the edges to avoid catching food particles or causing discomfort to the patient. The means of securing the plate  156 , stud  42 , and backing  46  is preferably a releasable connection, such as a threaded screw and tapped hole or other secure means that can be removed by the physician. 
   B. Secondary Magnet(s) 
   A collar  158 , carrying a secondary, focused energy magnet  38  similar in function to secondary magnets  38  previously described, is provided for wear during sleep. The collar  158  is desirably made of a webbing or other flexible belt-like material that is comfortable to the individual wearing it. For added patient comfort and convenience, the collar  158  is preferably covered in a soft cloth sleeve that may be slipped off of the collar and washed. Alternatively, a disposable cover (not shown) or an entirely disposable collar  158  may be employed. 
   The collar  158  may, in one embodiment, have an expandable (elastic) section, or it may be made entirely of an elastic belt material, so that the collar  158  may be comfortable and still provide stability for the magnet  38  mounted at the center front of the collar  158 . The collar  158  is equipped with a means for adjusting to a wide range of neck sizes. Such adjustment may be by belt, buttons or snaps, but in the preferred embodiment would use a hook and loop fastener such as Velcro® to provide adjustability. 
   The focused energy magnet  38  is positioned within a soft casing  160 , preferably of a polymer foam, and further attached to a mounting bracket  162 , e.g., by adhesive or fastener  164 . The mounting bracket  162  is secured to the adjustable collar  158 , e.g., by adhesive or fastener  166 , and positioned below the chin  165 . The magnet  38  is of a high energy type, such as neodymium, and is sized and shaped to concentrate the magnetic flux in one direction. The magnet  38  may be encased in a shielding material to further focus and direct the magnetic force toward the ferrous plate  156 . 
   The collar  158  maintains the magnet  38  at a distance D 1  from the plate  156  and in position, to permit an attraction between the plate  156  and the magnet  38 . The magnet  38  is oriented with the primary direction of magnetic flux being in a posterior-anterior direction, as depicted by arrows in  FIG. 28 . Due to the collar mounting bracket  162 , the magnet  38  is held more securely in place than the plate  156 . Therefore, attractive magnetic forces draw the plate  156  toward the magnet  38 . In this arrangement, as the plate  156  is drawn forward toward the magnet  38 , it places pressure on base of the tongue  34 , thereby moving the tongue  34  in an anterior direction. 
   In an alternative embodiment, the magnet  38  may be an electromagnet for exerting an adequate pull at the distance required to effect proper positioning of the tongue  34 . Such an electromagnet may be powered by a D.C. power supply or by a battery pack. 
   As shown in  FIG. 29 , the collar  158  may extend upward and sweep back behind the jaw  167 , to prevent rotation of the collar  158  during sleep. 
   V. Overviews of Other Systems 
   A. Hyoid Bone Attachment 
     FIG. 30  shows another system for treating sleep-related breathing disorders such as snoring, upper airway resistance syndrome and obstructive sleep apnea. The system includes at least one primary magnet  36  implanted by surgical attachment to the hyoid bone  170 , which is used in association with a complementary secondary magnet  38  externally worn on the chin, to position, stabilize and maintain the tongue in a preferred orientation in the oral cavity and airway in both humans and animals. The complementary magnetic forces serve to support and move the tongue  34  forward to prevent contact between the back of the tongue  34  and the pharyngeal wall, thus preventing occlusion of the airway. 
   The system shown in  FIG. 30  includes a device  168  sized and configured to be implanted by surgical attachment to the hyoid bone  170  (the hyoid bone  170  is a horseshoe-shaped bone of anterior neck located at the base of the tongue  34 ). 
   The device  168  includes a fulcrum  172 , which is affixed to the hyoid bone  170  by a bone screw  174 . Extending from the fulcrum  172  is an actuator  176  having a generally horizontal first arm  178  and a generally vertical second arm  180 . 
   Suitable material for arms  178  and  180  are an inert rigid material such as titanium, shaped memory alloy (Nitinol®), or a biologically compatible polymer such as reinforced polytetraf luoroethylene (Teflon®). Suitable materials, configuration, and length of arms  178  and  180  can be varied to maximize comfort and to minimize interference with swallowing and speech. 
   The primary magnet  36  is affixed to one end of the first arm  178 . 
   A collar  158  carries the secondary magnet  38 . The patient wears a collar  158  when asleep. The collar  158  is similar to the collar previously described and shown in  FIGS. 28 and 29 . However, as  FIG. 30  shows, in this arrangement, the distance D 2  between the primary magnet  36  and the secondary magnet  38  is considerably less than the distance D 1  between the primary magnet  36  and the secondary magnet  38  shown in  FIG. 28 . As shown in  FIG. 30 , the collar  158  orientates the secondary magnet  38  such that the primary direction of magnetic flux (represented by an arrow in  FIG. 30 ) attracts the primary magnet  36  in a downward direction. 
   The collar magnet  38  is encased in a soft casing material  160 , preferably polymer foam, and affixed to a bracket  162 , e.g., by adhesive or fastener  164 , which is further affixed, e.g., by adhesive or fastener  166 , to the collar  158  as was described for the earlier embodiment. 
   The material is configured to contact the chin  165  at  182 , preventing the collar  158  from moving upward due to the magnetic pull or due to movement during sleep, assuring that comfort and proper position are maintained. A space  184  between the bottom of the chin  165  and the top of the secondary magnet  38  provides room for the tissue and muscle between the mandible  186  and the hyoid bone  170  to be pulled downwardly by the attraction between the secondary magnet  38  and the primary magnet  36 . 
   As the primary magnet  36  is pulled downward, the tissue between the mandible  186  and hyoid bone  170  flexes downward, exerting a rotational force on the actuator arms  178  and  180 , with the center of rotation being the fulcrum  172 . At the upper end of the second arm  180  there is a paddle  188  configured to press in an anterior direction on the muscular tissue within the tongue  34 . This action holds the tongue  34  in an anterior direction, preventing occlusion of the airway by the back of the tongue  34 . 
   In alternate embodiment (see  FIG. 31 ), the actuator arms  178  and  180  extend from a U-shaped stirrup  190  providing a fulcrum point  192 . The actuator  176  is positioned in front of and above the hyoid bone  170  and sutured in place to the soft tissue, leaving approximately 2 to 3 mm of tissue between the stirrup  190  and the hyoid bone  170 . The actuator  176  is desirably coated with an expanded Teflon® PTFE (polytetrafluoroethylene) to encourage in growth of the tissue as the sutures  194  dissolve. 
   B. Mandible Attachment 
   1. First Embodiment 
     FIG. 32  shows another system for treating sleep-related breathing disorders such as snoring, upper airway resistance syndrome and obstructive sleep apnea. The system includes a device  196  carrying a more mobile primary magnet  36 , which is implanted within the tongue  34 , and a less mobile secondary magnet  38 , which is carried by an external collar  158  against the chin. 
   The device  196  comprises a bracket  198  coupled to an arm  200 . In this embodiment, the bracket  198  is affixed to the posterior portion of the mandible  186  using a bone screw  174  or other permanent means of attachment. The mandible  186  provides a stable platform. 
   The arm  200  is implanted into tongue tissue, reaching toward the back of the tongue  34  and sweeping upward. At the upper end of the arm  200  there is a paddle  201  configured to press in an anterior direction on the muscular tissue within the tongue  34 . 
   The arm  200  is pivotally attached to the bracket  198  with the pivot or hinge  202  allowing rotational movement around a point near the upper rear edge of bracket  198 . The primary magnet  36  is permanently affixed to the lower surface of the arm  200  approximately one-half of the way between the two ends of the arm  200 . 
   A secondary magnet  38  is carried by an external collar  158 , to be worn against the chin during sleep, as previously described. The secondary magnet  38  may be encased in a soft (preferably polymeric foam) pad  160  to provide comfort for the wearer, as previously described (see e.g.,  FIGS. 28 and 29 ). The foam pad  160  is affixed to and supported by a bracket  162  that is further affixed to a collar  158 , as also previously described. However, in this arrangement, the mounting position of the magnets  36  and  38  are in a more posterior direction than that of the embodiment shown in  FIGS. 30 and 31 , to effectuate desired movement of the tongue  34 . 
   In this arrangement, the polarities of the primary and secondary magnets  36  and  38  are non-complementary, i.e., the magnets  36  and  38  have like polarity. The like polarities establish repelling magnetic forces. 
   Thus, as depicted by arrow  204  in  FIG. 32 , due to the like polarities, the more mobile primary magnet  36  is repelled away from less mobile secondary magnet  38 . This repulsive force imparts a lifting moment to the device  196 , preventing the tongue  34  from falling backward into the mouth and thereby avoiding an apneic or hypopneic event. In this arrangement, the direction of lift is upward and forward, as depicted by arrow  206  in  FIG. 32 , because the pivot point of arm  200  causes the path of travel to describe a radius centered on the upper rear corner of the bracket  198 . 
   With reference now to  FIG. 33 , an alternative embodiment of the device  196  is illustrated. A bracket  198  is firmly affixed to the posterior surface of the mandible  186  using a bone screw  174 . A bellcrank  208  is rotatably mounted to bracket  198 , pivoting about a center point  210 . A primary magnet  36  is affixed to the lower surface of the bellcrank  208  and positioned at the anterior end of the bellcrank  208 . 
   For sleep, the user wears a collar apparatus  158  carrying a secondary magnet  38 , as described earlier (see e.g.,  FIGS. 28 and 29 ). In this arrangement, the polarities of the primary and secondary magnets  36  and  38  are complentary, i.e., the polarities are not alike. Thus, the less mobile secondary magnet  38  will attract the more mobile primary magnet  36 . The attraction imparts a downward pull, as depicted by arrow  212  in  FIG. 33 , on the anterior portion of the bellcrank  208 . A downward force on the arm  200  at will translate to an arcuate force, represented by arrow  214  in  FIG. 33 , resisting the tendency of the tongue  34  to fall backward during sleep and attendant muscle relaxation. 
   The materials of construction of the device  168  or  196  are desirably of biologically inert materials that have demonstrated the ability to be implanted and remain within the body without causing irritation, inflammation or rejection by the body. Suitable materials are polymeric (plastic) materials or metallic materials such as titanium or shaped memory alloys. The moving or floating parts of the present invention are preferably made of materials that are somewhat flexible and that will not affect speech or swallowing during non-sleeping hours. The implanted portions of the device  168  or  196  may be of, or coated by, a material that promotes in growth or attachment of the tissue to the implanted device  168  or  196 . Such materials are well known to the medical device industry. 
   It is believed that the restraint of the tongue  34  for treating sleep-related breathing disorders such as snoring, upper airway resistance syndrome and obstructive sleep apnea, does not require large forces. It is estimated that the required forces to be imparted to the device  168  or  196  when the collar  158  is worn are in the range of about 15 to 60 grams. 
   Thus, the lifting/rotating arms  178 ,  180  and  200  in the embodiments represented by  FIGS. 30 to 33  could be composed of a metallic coil spring that is imbedded in a polymeric coating, such as PTFE (Teflon®), or a silicone rubber compound. The degree of flexibility and rigidity required to provide sufficient lifting force during sleep, while not interfering with normal daytime activities such as speech and swallowing, could be readily attained by varying the wire gage, number of turns and the type of covering material. 
   2. Second Embodiment 
     FIGS. 34 to 37  illustrate another embodiment of the invention in which a device  216  carrying a primary magnet  36  can be implanted within the mandible  186  for treating sleep-related breathing disorders such as snoring, upper airway resistance syndrome and obstructive sleep apnea. The device  216  comprises a capsule  218  coupled to a lifting arm  220 . The capsule  218  includes a bore  222  in which the primary magnet  36  is positioned slidably and stabilized against the top end of the bore  222  by a light force coil spring  224 . Below the magnet  36  is a linkage mechanism  226  on which the magnet  36  rests or, alternatively, is attached to. 
   The linkage mechanism  226  has a connecting rod  230  contacting the bottom surface of the magnet  36 , which is coupled to a bellcrank  232 , which pivots about a pivot point  228 . The bellcrank  232  is coupled to the lifting arm  220  by a pull wire  236 . 
   It is to be understood that the length of the arms of the bellcrank  232  on opposite sides of the pivot point  228  may dissimilar. For instance, the bellcrank arm above the pivot point  228  may be longer than the bellcrank arm below the pivot point  228  to gain a leverage advantage. In this arrangement, travel distance for the magnet  36  is traded for increased force at the end of the lower arm  232 . These lengths may be designed to deliver the desired force at the end of the bellcrank  232  connected to the pull wire  236 . 
   The proximal end of a pull wire  236  is attached to the bellcrank  232 , e.g., threaded through hole  238  and tied. The wire  236  extends through a bore  240  in the lifting arm  220 , the distal end of the wire  236  being anchored to the interior of the distal end of the lifting arm  220 , e.g., threaded through hole  242  and tied. The lifting arm  220  includes a segmented portion  244 , such that as the pull wire  236  is drawn back, the segmented portion  244  of the lifting arm  220  curves, as represented by arrow in  FIG. 35 . The arm  220  includes a paddle  246  at the posterior end that is configured to press in an anterior direction on the muscular tissue within the tongue  34  as the arm  220  curves. 
   The method of curving a hollow tube is well known in the medical device industry and is used for many types of steerable therapeutic and diagnostic devices, such as catheters and endoscopes. The exterior of the curvable lifting arm  220  is desirably coated with a material such as expanded PTFE to promote in growth of tissue and provide stability for the implanted lifting arm  220 . 
   To implant the device  216 , the surgeon performs a procedure to open the skin and tissue beneath the chin  165  to gain access to the lower surface of the mandible  186 . The surgeon then drills a hole in the mandible  186  of an appropriate diameter and depth for the capsule  218  to be implanted. 
   The capsule  218  is then anchored into the mandible  186  using a bone cement of the type used in joint implants and similar procedures. Next, using a special procedure needle, the surgeon uses a locating template that temporarily attaches to the bottom of the capsule  218  to guide the procedure needle to create a path for the lifting arm  220 . The surgeon then inserts the special needle, palpating the tongue  34  to determine the optimal location for the posterior of the lifting arm  220 . The needle is then withdrawn and the sterile lifting arm  220  is slid into the incision made by the special needle. The anterior end of the lifting arm  220  includes an attachment means that will allow the lifting arm  220  end to be sealed to the bottom of the magnet capsule  218 . The incision is then closed. 
   After a suitable healing time to allow swelling and soreness to subside, the patient may begin to wear a collar  158  carrying the secondary magnet  38 , similar to that shown in  FIGS. 28 and 29 . As best seen in  FIG. 36 , in the absence of magnetic forces acting on the primary magnet  36  (i.e., when the collar  158  is not being worn) the primary magnet  36  rests against the top end of the bore  222 , as previously noted. When the collar  158  is worn, attractive magnetic forces between the complementary magnets  36  and  38  draw more the mobile primary magnet  36  to the bottom of the capsule  218 , as shown in  FIG. 37 . The downward movement of magnet  36  results in the lower arm  232  pivoting in an upward direction to draw the pull wire  236  back (anterior). 
   As the wire  236  is drawn back, the segmented portion  244  of the lifting arm  220  curves upward to effectuate an upward and anterior movement of the tongue  34 , mediating against OSA and hypopneas. Because the tongue  34  will not tend to occlude the airway, snoring that is exacerbated by a rearward tongue  34  position may also by reduced. 
   VI. Another System Overview (Tissue Displacement Using Suction) 
     FIGS. 38 to 41  illustrate another system  300  for treating sleep-related breathing disorders such as snoring, upper airway resistance syndrome and obstructive sleep apnea. Unlike the systems previously discussed, the system  300  does not employ magnets or ferrous materials. Instead, the system  300  uses suction (i.e., a vacuum) to position, stabilize and maintain a preferred orientation of tissue in an oral cavity and airway in both humans and animals. By using suction to move and stabilize tissue in a desired location and shape, the system  300  mediates or prevents the obstruction of the upper airway that results in sleep-related breathing disorders. And, as will be described, the system  300  achieves these results without permanent modification of the anatomy. 
   As shown in  FIG. 38 , the system  300  includes an oral device  302 , which conforms to the teeth or hard palate (see  FIG. 41 ). The oral device  302  has the structural features of oral device  104  shown in  FIG. 18 , which have been previously described and share common reference numerals. Like the oral device  104 , the oral device  302  is held in place by an intimate fit to the teeth and/or hard palate  28  (as shown in  FIG. 41 ) and/or by springs or elastic bands, all of which are well known and common in dental appliances. Like the oral device  104 , the oral device  302  is intended to be worn by the individual during sleep and then removed during waking hours. 
   As shown in  FIG. 38 , the system  300  also includes a suction cup  304 , a hollow supporting stem  306 , and a vacuum bulb  308 , which are carried by the oral device  302 . 
   As  FIGS. 38 and 39  show, the suction cup  304  desirably has a bead  310  which surrounds the face of the suction cup  304 . The bead  310  is sized and configured to press against the surface of the tissue (see  FIG. 40B ), creating an area of increased contact pressure, resulting in a tight seal against the tissue. Perforations  312  in the face of the suction cup  304  reach into the plenum chamber  324  within the suction cup  304  (see  FIG. 39 ). The face of the suction cup  304  which contacts the tissue may also have a shallow waffle type grid pattern to enhance evacuation of air from the area between the suction cup  304  and the surface of the tissue. 
   The stem  306  supports the suction cup  304 . The stem  306  is hollow to transport air between the suction cup  304  and the vacuum bulb  308 . The stem  306  is desirably flexible so that movement of the soft palate and uvula is not impaired, while imparting sufficient force to pull the soft palate and uvula in an anterior direction. 
   As  FIG. 39  shows, the vacuum bulb  308  communicates with a check valve  314  and an exhaust valve  316 . The body of the vacuum bulb  308  may be a flexible material with sufficient memory to expand after being depressed, creating suction forces, which are communicated via the hollow stem  306  to the suction cup  304 . 
   The bulb  308 , the stem  306 , and the suction cup  304  may be slidably mounted onto the oral device  302 , in the manner that magnets were slidably affixed to the oral device  104  described earlier. In use (see  FIG. 40A ), the individual would slide the vacuum bulb  308  in a backward (posterior) direction in the mouth, causing the suction cup  304  to come into contact with the soft palate  30  and/or uvula  32 . As  FIG. 40A  shows, the individual would then depress the vacuum bulb  308  by pressing upward (shown by an arrow in  FIG. 40A ). Air within the bulb  308  will exit through the exhaust valve  316  (shown by arrows in  FIG. 40A ), since air is unable to move toward the suction cup  304  because the check valve  314  prevents air movement in that direction. 
   As  FIG. 40B  shows, when the pressure against the vacuum bulb  308  is released (shown by an arrow in  FIG. 40B ), the bulb  308  expands, reducing the internal pressure. This creates a suction in the suction cup  304 , because the check valve  314  permits air movement toward the vacuum bulb  308  (as shown by an arrow in  FIG. 40B ). If desired, the individual may pump the suction cup  304  itself to further exhaust air, if needed, to assure an adequate suction grip on the tissue. 
   The exhaust valve  316  may be of a pressure limiting type of valve that will open if a predetermined amount of suction has been exceeded. Such a valve could have a calibrated spring to prevent maintaining an amount of suction that might result in tissue damage. If the vacuum bulb  308  was depressed more than required, the pressure regulating exhaust valve would leak until the predetermined level of suction was reached and then seal against further leakage. 
   The vacuum bulb  308  may be placed on the occlusal surfaces between upper and lower molars, allowing the suction to be created and replenished by a biting action. Alternatively, a primary suction bulb may be arranged as shown in  FIGS. 38 and 39 , and the amount of suction needed to overcome leakage may be supplied by a smaller occlusal bulb. 
   Various ancillary means may be applied to prevent leakage of the suction during the sleep period. For instance, a sealing gel material or dental adhesive might be applied to the bead of the suction cup, preventing air leakage during the night, in which case the suction applied when the device is placed in the mouth would be sufficient for the entire sleep period. 
     FIGS. 42 and 43  illustrate an alternative system  400  for treating sleep-related breathing disorders such as snoring, upper airway resistance syndrome and obstructive sleep apnea. The system  400 , like the system  300  uses suction (i.e., a vacuum) to position, stabilize and maintain a preferred orientation of tissue in an oral cavity and airway in both humans and animals. More particularly, the system  400  applies suction to stabilize and maintain the tongue  34  in a preferred orientation in the oral cavity and airway. The benefits of maintaining the tongue  34  in a preferred orientation using primary and secondary magnets have been previously described, and the use of suction achieves comparable benefits. 
   As shown in  FIG. 42 , the system  400  includes an oral device  402 , which can be sized and configured to be carried by either the bottom or upper teeth. In  FIG. 42 , the oral device  402  is sized and configured to be carried by the bottom teeth and has the structural features of oral device  126  shown in  FIG. 22 , which have been previously described and, accordingly, share common reference numerals. Like the oral device  126 , the oral device  402  is held in place by an intimate fit to the bottom teeth. Like the oral device  126 , the oral device  402  is intended to be worn by the individual during sleep and then removed during waking hours. 
   As also shown in  FIG. 42 , the system  400  also includes a left and right pair of suction cups  304  carried by the oral device  402 . Each suction cup  304  has a hollow supporting stem  306  and a vacuum bulb  308 , which are also carried by the oral device  402 . These elements are comparable in structure and function to the elements  304 ,  306 , and  308  shown and described in the embodiment illustrated in  FIGS. 38 and 39  and are, accordingly, assigned the same reference numeral. 
   As in the embodiment shown in  FIGS. 38 and 39 , the suction cups  304  in  FIG. 42  desirably each has a bead  310  that is sized and configured to press against the adjacent tissue, which, in this instance, is a side surface of the tongue  34  (see  FIG. 43 ). As in the  FIG. 39  embodiment, the vacuum bulb  308  in  FIG. 42  communicates with a check valve  314  and an exhaust valve  316 , to create suction in the respective suction cup  304  in response to an individual squeezing the vacuum bulb  308 . 
   In use (see  FIG. 43 ), the individual installs the oral device  402  on the bottom teeth. This installation brings the left and right suction cups  304  into association with the adjacent left and right sides of the tongue  34 . The individual then depresses the vacuum bulbs  308  by pressing against them, either individually or simultaneously. When the pressure against the respective vacuum bulb  308  is released, the bulb  308  expands to create a suction in the associated suction cup  304 . This has been previously described with reference to  FIGS. 40A and 40B . In  FIG. 43 , the suction causes the suction cups  34  to grip the sides of the tongue  34 . 
   The suction cups  304  are maintained by the oral device  402  in a desired anterior position within the oral cavity. Held relatively immobile by the bottom teeth, the suction cups  304  exert an anterior pulling force to the tongue  34 . The pulling force draws the tongue toward a more forward, stabilized position, shown in solid lines in  FIG. 43 . The anterior position of the tongue  34  shown in  FIG. 43  is comparable to the anterior position affected by the magnets  36 ′/ 38 ′ shown in  FIG. 23 . The stabilization of the tongue  34  in an anterior direction prevents a potential obstruction of the airway (which is shown in phantom lines in  FIG. 43 ). 
   As before described, one or more smaller, secondary vacuum bulbs  410  can be located on the oral device  402  in the occlusal area between upper and lower molars (see  FIG. 42 ). The vacuum bulbs  410  are coupled to the suction cups  304  and apply suction to the cups  304  by biting action. In this arrangement, primary suction can be supplied by the main vacuum bulbs  308 , and maintenance suction can be applied by biting on the secondary vacuum bulbs  410 . 
   Alternatively, one or more suction cups  304  for gripping the sides of the tongue, along with the associated stems  306  and vacuum bulbs  308 , can be carried by an oral device carried by the upper teeth, in a manner comparable to the way the magnets  132  are carried by the oral device  152  in  FIG. 27 . 
   The above described embodiments of this invention are merely descriptive of its principles and are not to be limited. The scope of this invention instead shall be determined from the scope of the following claims, including their equivalents.