Abstract:
A system and method for improving a sleep disorder is provided. The system includes an oral appliance having a mandibular occlusal plate operably coupled to a maxillary occlusal plate, the plates molded to fit an individual&#39;s jaw; an actuator and one or more sensors in communication therewith for sensing physiologic parameters of a user, the actuator operably coupled to the maxillary occlusal plate for linearly advancing or retracting the mandibular occlusal plate based on commands received from a processing device.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates generally to a system and method for a sensor driven intelligent oral appliance. In particular the invention relates to a system and method for a sensor driven intelligent oral appliance that is used to treat sleep disordered breathing. 
       BACKGROUND OF THE INVENTION 
       [0002]    During sleep the muscles of the airway become relaxed. The relaxation of these muscles in turn reduces the diameter of the airway. Typically, the airway of a person with sleep related breathing disorders is already restricted or reduced in size, and this natural relaxation reduces the airway further. The most common sleeping disorder is obstructive sleep apnea (OSA), which is characterized by recurring collapse of the upper airway during sleep, resulting in sleep fragmentation and oxygen desaturation. OSA is defined as the occurrence of 5 or more episodes of complete (apnea) or partial (hypopnea) upper airway obstruction per hour of sleep (apnea-hypopnea index [AHI]) and is estimated to occur in around 24% of middle-aged men and 9% of women. The gold standard treatment for OSA is to pneumatically splint open the upper airway during sleep using continuous positive airway pressure (CPAP) devices. Although CPAP is highly efficacious in preventing upper airway collapse, patient acceptance, tolerance, and adherence is often low, thereby reducing effectiveness. Therefore, there is a significant need for effective alternative treatments. 
         [0003]    Oral appliances have emerged as an alternative to CPAP for OSA treatment. Oral appliances are designed to improve upper airway configuration and prevent collapse through alteration of jaw and tongue position. The most common mechanism of action is to hold the lower jaw in a more anterior position. These appliances are variously termed “mandibular advancement devices (MAD),” “mandibular advancement splints (MAS),” or mandibular repositioning appliances (MRA).” MAD are generally customized devices fabricated from dental casts of a patient&#39;s dentition and bite registrations by a dentist. Generally the greater the level of advancement, the better the treatment effect, although this must be balanced against potential increase in side effects (dryness, jaw pain, bite changes, etc.). 
         [0004]    However, above 50% of maximum advancement of the jaw there is an associated increase in reported side effects. A titration approach to determine optimal level of advancement with gradual increments over time is thought to optimize treatment outcome, although no standardized titration procedure currently exists. There is also little knowledge of how often to follow-up patients on MAD treatment for device adjustment. More information about these aspects of MAD therapy could help improve long-term effectiveness and adherence. A significant advance in single-night titration methodology has occurred with the recent development of a commercially available remotely controlled mandibular protrusion device. This protrusion device connects to upper and lower dental trays containing impressions of the patient&#39;s dentition and advances the mandible by moving forward the lower tray during polysomnographic monitoring. During the sleep titration a technician manually initiates forward movement of the lower dental tray in 0.2-0.6 mm increments in response to the appearance of apnea events. The technician continues with the advancement (within the patient&#39;s predetermined range of motion) until apena events are eliminated from sleep or until the patient&#39;s maximal allowed protrusive level is reached. 
         [0005]    Such single-night titration results in mandibular advancement that is set for the entire duration of sleep and this advancement is unaltered for the entire time-period MAD as used for treating sleep apnea. 
         [0006]    However, sleep is a dynamic physiological phenomenon. There is significant night-night variability in duration, depth of sleep and sleep posture, all of which directly correlate with the number and severity of apnea events. Given this dynamic nature of sleep, a static MAD maintaining advanced mandibular posture for extend periods of time, could elevate the risk for side effects in the process of improving sleep quality. 
         [0007]    For example, peer-reviewed studies have reported that the avoidance of supine positions leads to a decrease in the number and severity of obstructive episodes. In supine posture, the upper airway caliber and resistance are greater and thus, the tendency for the upper airway to collapse further is greater in the supine position compared to the lateral position. Sleep stages (REM v/s NonREM) also similarly correlate with the severity of apnea events in a night&#39;s sleep. 
         [0008]    Accordingly, there is a need for an oral appliance that solves the aforementioned problems associated with conventional devices and methods for treating sleep related disorders. In particular there is a need for an intelligent oral appliance that results in patients having less pain and fewer complications by not having to have their jaws protrude forward unnecessarily leading to improved compliance. Continuous gathering of data may also lead to optimal management of the sleep disorder. 
       BRIEF SUMMARY OF THE INVENTION 
       [0009]    The problems outlined above are addressed by the system and method for a sensor driven oral appliance device in accordance with the invention. The system monitors changes in physiological parameters in real-time and appropriately advances the mandible to treat sleep related disorders. Also, as opposed to a human technician manually titrating the device, the invention relies on a machine driven algorithm to change the position of the mandible thus ensuring a greater degree of accuracy. 
         [0010]    The system for improving a sleep disorder in accordance with the invention includes an oral appliance having a mandibular occlusal plate operably coupled to a maxillary occlusal plate, the plates molded to fit an individual&#39;s jaw; an actuator including a motor, a gear assembly and one or more sensors in communication therewith for sensing physiologic parameters of a user, said actuator operably coupled to said maxillary occlusal plate for linearly advancing or retracting said mandibular occlusal plate; a knowledge base that provides data on a plurality of sleep disorder conditions and normative data necessary to correct said sleep disorder conditions; a processing device in operable communication with the one or more sensors and said knowledge base, the processing device configured to (a) receive said physiologic parameter measurements from the user; (b) cross reference said physiologic parameter measurements with said knowledge base to generate a cross referenced data result indicative of a presence and/or severity of a sleep disorder event; (c) calculate a determined amount of linear movement necessary to improve the sleep disorder event to return to a normative condition; (d) transmit said determined amount to said motor; and (e) cause said maxillary occlusal plate to linearly advance or retract said mandibular occlusal plate by said determined amount to improve said sleep disorder. 
         [0011]    A method for improving a sleep disorder is also provided. The method includes providing an oral appliance including a mandibular occlusal plate operably coupled to a maxillary occlusal plate, said plates molded to fit an individual&#39;s jaw; providing an actuator including a motor, a gear assembly and one or more sensors in communication therewith for sensing physiologic parameters of a user, said actuator operably coupled to said maxillary occlusal plate for linearly advancing or retracting said mandibular occlusal plate; providing a knowledge base that provides data on a plurality of sleep disorder conditions and normative data necessary to correct or improve said sleep disorder conditions; providing a processing device in operable communication with said one or more sensors and said knowledge base, said processing device configured to (a) receive said physiologic parameter measurements from said one or more sensors; (b) cross reference said physiologic parameter measurements with said knowledge base to generate a cross referenced data result indicative of a presence and/or severity of a sleep disorder event; (c) calculate a determined amount of linear movement necessary to correct the sleep disorder event to return to a normative condition; (d) transmit said determined amount to said motor; and (e) cause said maxillary occlusal plate to linearly advance or retract said mandibular occlusal plate by said determined amount to correct said sleep disorder. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: 
           [0013]      FIG. 1  is a schematic of the system in accordance with the invention. 
           [0014]      FIG. 2  is a skeletal representation of maxilla  30  and mandible  32 . 
           [0015]      FIG. 3  is an illustration of a bilateral screw driven oral appliance in accordance with one aspect of the invention. 
           [0016]      FIG. 4  is an illustration depicting another aspect of the invention using a front screw driven oral appliance. 
           [0017]      FIG. 5  is an illustration depicting the implementation of another aspect of the invention using front screw driven oral appliance utilizing a headband including an electronics board and a pulse oximeter. 
           [0018]      FIG. 6  is an exemplary logic flowchart generally depicting the algorithm of the system with a single sensor input in accordance with the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]    Referring now to  FIG. 1  a schematic of the system  10  in accordance with the invention is illustrated. The system broadly includes sensor  12  for sensing various physiologic parameters during an individual&#39;s sleep state. For example sensor  12  may include a pulse oximeter that detects changes in an individual&#39;s oxygen saturation. Sensor  12  may also be a position sensor that detect whether the patient is lying in a supine or lateral position. Sensor transmits physiologic parameters collected during the sleep cycle to microprocessor or controller  14 . Controller  14  is powered by a source of power  22 . Those of skill in the art will appreciate that source of power  22  may include one or more batteries or may include an AC source of power. 
         [0020]    Controller  14  includes memory including a knowledge database of sleep disorders, one or more software algorithms operable to compare the data transmitted by sensor  12  to the sleep disorder knowledge database and predict the presence and/or severity of a sleep disorder event such as apnea. Controller may also include safety controls such as maximum and minimum advancement limits. Controller  14  may be an 8-bit or 16-bit microcontroller. 
         [0021]    Controller  14  is in operable communication with actuator  16  and transmits a signal to actuator  16  to increase or decrease the protrusion of an individual&#39;s mandible  32  (as best seen in  FIG. 2 ) by an amount that will improve the symptoms of the sleep disorder. Actuator  16  may be a micro motor such as a DC motor, pancake, stepper, servo or piezo motor. Actuator  16  may comprise two actuators, one each for the left and right sides of the individual&#39;s mandible. 
         [0022]    The system  10  may also include a patient web or desktop application  20  whereby data is transmitted (wired or wirelessly) from data transmission unit  24  to the web application  20  to provide an individual patient or their care team (dentist, sleep specialist and the like) with feedback regarding sleep disorder events on any particular night and how the oral appliance  18  responded. Alerts may be generated based on activity deemed outside the normal functioning range and shared among the patient and authorized care team members. Data may be transmitted via a wired set-up or may use wireless Bluetooth, WiFi and/or cellular means. 
         [0023]    The system  10  in accordance with the invention may also include a status indicator, such as a display, that visually indicates the sleep patterns and/or the operation and/or performance and/or efficacy of the system  10 , the oral appliance  18  or both. 
         [0024]    Referring now to  FIG. 3 , one aspect of an intelligent oral appliance  18  in accordance with the invention is depicted. Oral appliance  18  could be custom molded or fabricated using CAD-CAM models. Oral appliance  18  includes a maxillary occlusal plate  34  that is fitted to an individual&#39;s maxillary dentition  30  and a mandibular occlusal plate  36  that is fitted to an individual&#39;s mandibular dentition. The mandibular occlusal plate  36  is structured to engage the maxillary occlusal plate via connector  38 . Connector  38  may be integrally molded with mandibular occlusal plate  36  or may be a separate piece that snap fits with mandibular occlusal plate  36 . Maxillary occlusal plate  34  includes a bilateral advancement screw  40  operably coupled thereto. Bilateral advancement screw  40  includes motor  56  which may comprise a DC, pancake, stepper, servo or piezo motor. Bilateral advancement screw  40  includes electronics  58 , such as a motor drive and one or more sensors to sense position, airflow and the like, that are structured to transmit data to controller  14  and receive commands from controller  14  to impart different amounts of mandibular advancement to the mandibular occlusal plate  36 . Controller  14  may also be connected to additional sensors such as pulse oximeter, EEG and the like to sense related physiological parameters. Those of skill in the art will appreciate that one or more sensors may be embedded in the motor drive board while other sensors (including EEG, plus oximeter) may be attached via connectors/cables to the controller which then communicates with the motor. Upon receiving data from the sensors, the controller  14  compares the data to knowledge base stored in memory to determine the amount of movement required to improve the sleep disorder. Controller  14  then sends a signal to motor  56  to moveably advance or retract by the determined amount. If the command is to advance, screw  40  is driven by motor  56  to push against connector  38  which in turn moves the mandibular occlusal plate  36  forward by the determined amount. If the command is to retract, motor  56  drives screw  40  backwards which releases the force against connector  38  which allows the mandibular occlusal plate  36  to retract and move backwards. Those of skill in the art will appreciate that bilateral advancement screw  40  includes a counterpart screw on the opposite side of the maxillary occlusal plate  34 . As seen the screw advancement device is coupled to via cable  60  to controller  14  and source of power  22   
         [0025]    Referring now to  FIG. 4  another aspect of an intelligent oral appliance  18  is depicted. Like pieces are numbered with like numerals. Oral appliance  18  includes a maxillary occlusal plate  34  that is fitted to an individual&#39;s maxillary dentition  30  and a mandibular occlusal plate  36  that is fitted to an individual&#39;s mandibular dentition  32 . Oral applicance  18  includes a front screw driven device  48  operably coupled to the maxillary occlusal plate  34 . Front screw driven device  48  includes a rotating screw shaft  50 , a gear  54  operably coupling the screw shaft  50  to a motor  56 . Those of skill in the art will appreciate that motor  56  may comprise a DC, pancake, stepper, servo or piezo motor. Front screw driven device  48  also includes electronics  58 , such as a motor drive, and one or more sensors to sense oxygen saturation, EEG, sleep position, airflow and the like that are structured to transmit data to controller  14  and receive commands from controller  14 . Those of skill in the art will appreciate that one or more sensors may be embedded in the motor drive board while other sensors (including EEG, plus oximeter) may be attached via connectors/cables to the controller which then communicates with the motor. 
         [0026]    The mandibular occlusal plate  36  includes a receptacle  42  such as a lingual bar or lingual slot that traverses left and right sides of the mandibular occlusal plate  36 . In the case of a lingual bar  42 , it may be integrally molded with mandibular occlusal plate  36  or may be a separate piece that snap fits with mandibular occlusal plate  36 . Maxillary occlusal plate  34  includes a front advancement screw  44  operably coupled thereto. Front advancement screw  44  includes a mating piece  62  that is structured to engage receptacle  42 . Mating piece  62  may comprise a hook or clasp. Hook or clasp  62  is operably coupled to the rotating screw shaft and receives commands through electronics to moveably advance or retract which in turn causes advancement and retraction of mandibular occlusal plate  36  via engagement with receptacle  42 . Those of skill in the art will appreciate that the male and the female hook/clasp and receptacle/bar/slot assembly can be interchangeably positioned between the two arches so as to have the male piece in the mandibular plate and the female receptacle in the maxillary plate. Other implementations may include a ball-clasp like structures. As shown, cable  60  operably couples motor  56  and electronics  58  to controller  14 . However, those of skill in the art will appreciate that controller  14  may wirelessly communicate with motor  56  and electronics  58 . 
         [0027]    Referring now to  FIG. 5  an alternative aspect of the oral appliance in accordance with the invention is depicted. Like pieces are numbered with like numerals. Oral appliance  18  includes a maxillary occlusal plate  34  that is fitted to an individual&#39;s maxillary dentition  30  and a mandibular occlusal plate  36  that is fitted to an individual&#39;s mandibular dentition  32 . Oral applicance  18  includes a front screw driven device  48  operably coupled to the maxillary occlusal plate  34 . Front screw driven device  48  includes a rotating screw shaft  50 , a gear  54  operably coupling the screw shaft  50  to a motor  56 . Those of skill in the art will appreciate that motor  56  may comprise a DC, pancake, stepper, servo or piezo motor. An elastomeric or non-elastomeric headband  64  supports an electronics board  66  having a microprocessor, battery and other electronics thereon. Headband  64  also supports at least one sensor such as a pulse oximeter, body position and/or sleep position sensor. As shown, cable  60  operably couples electronics board  66 , including microprocessor, with motor  56 . However, those of skill in the art will appreciate that cable  60  may be eliminated and microprocessor may wirelessly communicate with motor  56 . Front screw driven device  48  may also include and additional source of electronics  58 , such as a motor drive, and one or more additional sensors to sense EEG, sleep position, airflow and the like that are structured to transmit data to controller  14  and receive commands from controller  14 . Alternatively, all sensors may be located in the headband  64 . The mandibular occlusal plate  36  includes lingual bar or lingual slot  42  that traverses left and right sides of the mandibular occlusal plate  36 . If a lingual bar  42  is used, it may be integrally molded with mandibular occlusal plate  36  or may be a separate piece that snap fits with mandibular occlusal plate  36 . Those of skill in the art will appreciate that a lingual slot  42  will necessarily be molded into the mandibular occlusal plate  36 . Maxillary occlusal plate  34  includes a front advancement screw  44  operably coupled thereto. Front advancement screw  44  includes hook  62  that is structured to engage lingual bar  42  and that is moveably advanceable. Hook  62  is operably coupled to the rotating screw shaft and receives commands through electronics  58  or  68  to moveably advance or retract which in turn causes advancement and retraction of mandibular occlusal plate  36  via engagement with lingual bar  42 . 
         [0028]    Any of the appliances disclosed above and set forth in  FIGS. 3, 4 and 5  may be used to record bruxism based on the input gathered from the controller  14 . The oral appliance may also be used to alter the user&#39;s position in the event of prolonged apnea. The oral appliance for example could include an auditory or other type of alarm. For example, prolonged supping posture may lead to increased severity of the apnea and after a set threshold, the appliance may buzz or vibrate or sound an audio-visual alarm to wake and prompt the user to shift positions. In addition the web/mobile/desktop application may include a cognitive behavioral training module that is customized to the user based on the data gathered from the intelligent oral applicance. 
         [0029]    Referring now to  FIG. 6  an exemplary logic flow chart with a single sensor input is depicted. In the initial state  70  the motor  56  advance the screw  40 ,  44  to allow the mandibular plate  36  to counter a patient&#39;s overbite. SpO2 is checked for apena events within a defined period of time  72 . If apnea events are absent the microprocessor via sensors continues to check SpO2  72 . If apnea events are detected  76  the motor  56  causes the screw  40 ,  44  to advance the mandible in predetermined increments without exceeding a pre-determined maximum protrusion limit  78 . The microprocessor continues to monitor SpO2 for apnea events  80  with a defined interval  80 . If an apnea event has not been detected  82  then the microprocessor  14  transmits a command or signal to the motor to move the mandible back in predetermine increments not to exceed the distance to counter the overbite. The cycle continues with the microprocessor monitoring SpO2 for apnea events  72 . 
         [0030]    As will further be appreciated by those skilled in the art, the processes herein described may be embodied as a system, method or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that may all generally be referred to as a “circuit,” “module” or “system.” Furthermore, the present invention may take the form of a computer program product embodied in any tangible medium of expression having computer usable program code embodied in the medium. 
         [0031]    The processes comprising the method of the present invention have been described with reference to flow diagrams illustrating exemplary steps. It will be understood that each block of the flowchart diagrams, and combinations of blocks in the flowchart diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart diagram block or blocks. 
         [0032]    These computer program instructions may also be stored in a computer-readable medium that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable medium produce an article of manufacture including instruction means which implement the function/act specified in the flowchart block or blocks. 
         [0033]    The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions/acts specified in the flowchart diagram block or blocks. 
         [0034]    Although the present invention has been described with reference to certain aspects and embodiments, those of ordinary skill in the art will appreciate that changes may be made in form and detail without departing from the spirit and scope of the invention.