Patent Publication Number: US-9883896-B2

Title: Jawbone distraction system and a control method thereof capable controlling operation using a remote control

Description:
TECHNICAL FIELD 
     The present invention relates to a jawbone distraction system and control method thereof and more particularly, to a jawbone distraction system and control method thereof, including a jawbone extension apparatus, a remote controller and a monitor, the jawbone distractor being configured to allow a horizontal shift of alveolar bone as well as performing vertical jawbone distraction, being precisely controlled in a wireless mode and configured to control a drive of the jawbone distractor through the remote controller while ascertaining a driving state by the monitor. 
     BACKGROUND ART 
     There are so many cases of causing deformities due to alveolar bone in malformed maxillofacial patients. For example, those can be called patients with cleft lips and palates, jutting chins, deformation, and edentulous patients arising from traumas. 
     In case of a child with cleft lip and palate, it has a cicatrix after an early surgical operation and therefore meets with an impediment to growth of bone to cause deformation of jawbone. As a chin is normally growing despite abnormal growth of maxilla, the circumstance around a nose becomes to be recessed (undergrowth of upper jawbone) or the chin becomes to be protruded (overgrowth of lower jawbone). For solving these troubles, it is usual to conduct a corrective surgery for maxilla and chin in the end of the season when the maxilla is growing (a teenage), which means a surgical procedure to pull an undergrown maxilla frontward so as to revive the volume of the central portion in face or push a chin backward so as to make the chin shown smaller, with which a corrective treatment for teeth is accompanied to make rows of teeth fit well each other between the top and the bottom. 
     With respect to a jutting chin, there may be two cases of bad and acceptable teeth engagements. The latter can be correctable by simple surgery, whereas the former is inevitable to have surgery and correction. If even a correction is not contributable to occlusion because a jutting chin is too excessive, it is necessary to perform surgery for push the whole body of jaw including teeth and alveolar, which is regarded as the greatest surgery in the cases called jutting chins. It is also necessary to perform a dental correction before and after such surgery because the surgery can not be still acceptable thereto. 
     In other words, it is impossible for the cleft lip and palate and the jutting chin to be with a teeth shift by way of a corrective treatment in a classic manner because of discontinuity of alveolar, from which there are generated a malocclusion with lateral disharmony of maxilla due to cicatrix tissues after surgery, and a failure of thrive of intermediate face due to a frontward undergrowth of maxilla after surgery. 
     As a way for remedying faces and reconstructing rows of teeth for deformed patients and edentulous patients arising from traumas, it is required to perform surgery such as alveolar bone distraction or extension for frontward and backward teeth shifts, or a corrective treatment for prosthetic restoration. 
     As a surgical treatment for the deformed maxillofacial patients and defective patients, for the purpose of increasing a length of chin bone in inherent and acquired deformities, it is possible to result in an appropriate face and occlusion by adjusting a direction of distraction with a cutoff position and angle of bone. To do this, jawbone distractors are needed and can be briefly classified into extra-oral and intra-oral types. 
     An extra-oral distractor is an apparatus that is installed out of an oral cavity and controlled at the outside of the skin, advantageous in simplicity of installation, easiness of handling, controllability of distracting direction and so on, but inconvenient for a social life and may remain a permanent scar on the face. 
     An intra-oral distractor is an apparatus that is installed within an oral cavity, being widely used due to the shortness of the extra-oral one. However, even the intra-oral distractor may also cause various problems involved in aesthetic view, life convenience, complication and so on because its control part is located out of the oral cavity. 
     With the development of medial machinery and arts, corrective treatments have been diversified through surgical operations at maxillofacial parts. Among them, a technique of bone distraction has been being used to extend horizontal and vertical lengths of maxilla and chip and broaden an arch. The horizontal bone distraction has acted as a limit to clinical application because of its structural property in the bone distractor. 
     In recent years, being published are the studies about influences of bone distraction to peripheral tissues during bone distraction, particularly various analyses about influences of continuous, interrupted-continuous and intermittent forces to bone distraction, but still in shortness of objective materials since it is difficult to control minute forces due to a mechanical limitation of the distractor. Furthermore, during bone distraction, the feature of bone distractor necessitating external control may cause a complication such as an inflammation and a skin cicatrix due to contagion from an external projection. Therefore, there is a need for a jawbone distractor capable of being controlled more precisely without any external projection, hence free from a complication. 
     Generally, bone distracters being commercialized these days are mostly related to vertical bone distraction for recovering vertically defected bones, but horizontal alveolar shifters highly usable for corrective treatment region are almost not applied. Therefore, it is also required an apparatus capable of horizontally shifting an alveolar bone as well as performing vertical bone distraction. 
     In regard to the current technology of bone distraction, there are accompanied with limitations and complications such that an inadequate distraction force may be applied to a reviving tissue to generate a newly deformed bone, a direction of distraction may be set due to a failure of setting a treatment plan, an error for a surgical process, and a misuse of an apparatus, and excessive distraction of soft tissues may cause damage to peripheral soft tissues. 
     Therefore, the present invention provides a jawbone distraction system capable of horizontally shifting an alveolar as well as allowing vertical bone distraction, being precisely controlled in a wires mode and free from a complication without any outward projection. 
     DISCLOSURE 
     Technical Problem 
     The present invention is directed to provide a system and control method for jawbone distraction, which is capable of horizontally shifting an alveolar bone as well as allowing vertical bone distraction, being configured to permit a precise wireless control thereto and control drive with a remote controller while ascertaining a driving state thereof by way of a monitor. 
     Technical Solution 
     To solve the technical problem, according to the present invention, a jawbone distraction system, including a micro-actuator and an actuator controller controlling the micro-actuator, being formed to include a jawbone distractor installed to an upper bone and a lower bone connected to the upper bone and configured to adjust an interval between the upper and lower bones, and a monitor generating and wirelessly transmitting an actuator control signal to the jawbone distractor, may further include: a remote controller including a forward shift key and a reverse shift key that set the micro-actuator to shift each in a forward direction and a reverse direction, in which the monitor may be configured to include an arithmetic processor generating an actuator control signal in response to a forward shift key signal and a reverse shift key signal that are received from the remote controller. 
     Further according to the present invention, a jawbone distraction system may include a micro-actuator and an actuator controller controlling the micro-actuator, being formed to include a jawbone distractor installed to an upper bone and a lower bone connected to the upper bone and configured to adjust an interval between the upper and lower bones, and a monitor generating and wirelessly transmitting an actuator control signal to the jawbone distractor, in which the monitor may be configured to include: a key input unit including a forward shift key and a reverse shift key that set the micro-actuator to be shifted each in a forward direction and a reverse direction; and an arithmetic processor generating an actuator control signal in response to a forward shift key signal and a reverse shift key signal that are received from the key input unit. 
     The actuator controller may include: an actuator microcontroller wirelessly receiving the actuator control signal from the arithmetic processor; an actuator driver driving the micro-actuator in response to the actuator control signal that is received by the actuator microcontroller; and an actuator state detector detecting a voltage of a device serially coupled to the micro-actuator or a current signal of an input node of the micro-actuator as a state detection signal. 
     Further according to the present invention, a jawbone distraction system, including a micro-actuator and an actuator controller controlling the micro-actuator, including a jawbone distractor installed to an upper bone and a lower bone connected to the upper bone and configured to adjust an interval between the upper and lower bones, may further include: a remote controller including a forward shift key and a reverse shift key that set the micro-actuator to shift each in a forward direction and a reverse direction, in which the actuator controller may be configured to include: an actuator microcontroller generating an actuator control signal in response to a forward shift key signal and a reverse shift key signal that are received from the remote controller; and an actuator driver driving the micro-actuator in response to the actuator control signal that is received by the actuator microcontroller. 
     The actuator controller may further include a shift detection sensor detecting a shift distance of a lower bone support of the jawbone distractor. 
     The monitor may be configured to display an image, where is shifted the lower bone support of the jawbone distractor, in an X-ray image in response to a shift distance detection signal that is wirelessly received from the actuator controller. 
     An interface of the actuator controller and the monitor may use RS-232C, the micro-actuator may be a supersonic motor using a piezoelectric ceramic, and the micro-actuator may be controlled by a mode of PWM (Pulse Width Modulation). 
     The jawbone distractor may include: a lower bone support comprising an actuator installation unit fixedly installing the micro-actuator at the center and installed in a lower bone; an upper bone support installed in an upper bone connected to the lower bone and comprising a nut portion, into which a shaft having a bolt portion of the micro-actuator is inserted, at the center; and a support rod fixed to both left and right sides of the upper bone support and penetrating left and right sides of the lower bone support. 
     The upper bone support may include an upper bone connector including a fixing hole for helping installation in the upper bone, in which the lower bone support comprises a lower bone connector including a fixing hole for helping installation in the lower bone, and a support rod passing a support rod passage hole of the lower bone support may be configured to pass both left and right holes of a support rod fixer located at the end of the lower bone support. 
     The micro-actuator may include a shaft with screw threads, the shaft being configured to shift upward and downward while rotating, and the actuator controller may be located under the actuator installation unit of the lower bone support and over a support rod fixer. 
     The micro-actuator may be formed of a piezoelectric ceramic pillar and a shaft, wherein the shaft is located at the center of the piezoelectric ceramic pillar, wherein the shaft comprises screw threads and is configured to shift up and down while rotating, wherein the piezoelectric ceramic pillar comprises a cover enclosing the outside, wherein an outer side of the cover is connected to a signal transfer line. 
     Further according to the present invention, a method for driving a jawbone distraction system configured to include a jawbone distractor, a remote controller and a monitor, may include: an initializing step setting a motor step, a shift distance interval and a shift time period in the monitor and resetting (clearing) a counter; a power factor clear step setting a power factor to ‘0’; an interrupt enable step making an interrupt flag of a microcontroller of the jawbone distractor to be enabled; a key input determination step determining whether a key has been input into a key input unit; an interrupt flag disable determination step determining whether the interrupt flag is disabled if the key has been input into the key input unit in the key input determination step and returning to the interrupt enable step if the interrupt flag is disabled; a pulse on-time determination step determining whether a pulse on-time is ‘0’ if the interrupt flag is not disabled in the interrupt flag disable determination step and returning to the power factor clear step if the pulse on-time is ‘0’; a counter value determination step reading and comparing a counter value with the pulse on-time and one period (total time) unless the pulse on-time is ‘0’ in the pulse on-time determination step; and a pulse on-time &lt; counter value ≦ one period step determining whether a stop mode is present if the counter value is larger than the pulse on-time but smaller than the one period (total time) in the counter value determination step, setting the power factor to be a preset minimum power factor value unless the stop mode is present, an actuator controller stopping actuator control, reducing a stored power factor value by one and returning to the power factor clear step. 
     The method for driving a jawbone distraction system may further include: a none-key input processing step resetting the counter unless the key has been input into the key input unit in the key input determination step, determining whether the stop mode is present, storing the power factor as a preset minimum power factor value unless the stop mode is present, the actuator controller stopping the actuator control, and reducing the stored power factor value by one; and a power factor determination step determining whether the stored power factor value is ‘0’ after the non-key input processing step, being terminated if the power factor value is ‘0’ and returning to the power factor clear step unless the power factor value is ‘0’. 
     The method for driving a jawbone distraction system may further include: a step of a counter value &gt; one period or a counter value ≦ pulse, resetting the counter if the counter value is larger than the one period in the counter value determination step, determining whether a start mode is present, storing the power factor as a preset maximum power factor value if the start mode is present, increasing the stored power factor value by one, the actuator controller beginning (on) the actuator control, and returning to the power factor clear step. 
     Further according to the present invention, a method for driving a jawbone distraction system configured to include a jawbone distractor, a remote controller and a monitor, may include: an X-ray image loading step reading a preliminarily stored X-ray image by an arithmetic processor of the monitor; a shifter setting step setting a shifter, in which a lower bone support is installed, in the X-ray image in the arithmetic processor of the monitor; a normal operation determination step determining whether a normal state is present by comparing a preliminarily stored reference signal with an actuator state detection signal, which is received from the jawbone distractor, in the arithmetic processor of the monitor, and terminating with outputting an alert to inform abnormality unless the normal state is present; a shift detection signal reception step receiving a shift detection signal from the jawbone distractor by the arithmetic processor of the monitor if the normal state determination step determines that the normal state is present; and a shifter shifting step outputting an image, on which a shifter in which a lower bone support is installed is shifting according to a shift detection signal, in the X-ray image. 
     The method for driving a jawbone distraction system may further include: a jawbone distractor drive end determination step determining whether the jawbone distractor is stopped, from an actuator control signal that is generated from the arithmetic processor of the monitor, or from the actuator state detection signal or the shift detection signal that are received from the jawbone distractor, in the arithmetic processor of the monitor, terminating the arithmetic processor of the monitor if the jawbone distractor is stopped, and returning to the normal operation determination step unless the jawbone distractor is stopped. 
     Advantageous Effects 
     According to a system and control method for jawbone distraction, a jawbone distractor is capable of horizontally shifting an alveolar bone as well as allowing vertical bone distraction, being configured to permit a precise wireless control thereto and control drive with a remote controller while ascertaining a driving state thereof by way of a monitor. Thus it is possible for the jawbone distractor to be controlled wirelessly and automatically in precision without outward projection, so that there is no anxiety for complication. 
     While a bone distractor of the related art is exposed at the outside, penetrating the skin, a jawbone distractor of the jawbone distraction system according to the present invention, i.e. Micro-Actuator-Generated Distractor (MAGD), is installable completely within an oral cavity and workable by a remote controller, without revision surgery for driving the jawbone distractor, having an aesthetic merit even after surgery. 
     While a bone distractor of the related art is enabled with bone distraction through direct actuation one or two times a day by a patient guardian, a jawbone distraction system of the present invention uses an MAGD to execute remote control with more easiness and simplicity, offering manipulation and convenience. 
     A jawbone distraction system according to the present invention is workable with distraction/compression of jawbone and with cyclic tensile strain, capable of granting a continuous force as well as an intermittent force. 
     A jawbone distraction system of the present invention is capable of allowing bone distraction in the unit of micrometer, having excellent precision, reducing the possibility of contagion, i.e. a compliment, from an external wound because there is no part exposed outward. 
     Moreover, a jawbone distraction system can be controlled wirelessly, providing basic information for developing intra-mouth micro-actuator driven bone distractors suitable for Koreans. For instance, exact measurement values taken from analyzing radiographs and practical anatomy with Koreans can be used as outlined design materials for developing bone distracters with micro-actuators, by which jawbone distracters suitable for Koreans can be manufactured. 
     A jawbone distraction system of the present invention is advantageous, for clinical application, in reducing side effects after treatment and improving recuperation after surgery, lightening social expenses caused from medical and legal disputes due to aftereffects, and saving medical payments of patients. 
     Especially, a jawbone distraction system of the present invention is convenient in use and controllable with high precision and accuracy. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  is a schematic illustrating a jawbone distraction system of the present invention. 
         FIG. 2  is a schematic illustrating appearances of a jawbone distractor according to an embodiment of the present invention. 
         FIG. 3  illustrates an example of a micro-actuator according to an embodiment of the present invention. 
         FIG. 4  is a schematic illustrating a configuration for driving a jawbone distraction system of the present invention. 
         FIG. 5  is a schematic illustrating a driving feature of an actuator driver of  FIG. 4 . 
         FIG. 6  is a schematic illustrating a driving mechanism of a piezoelectric motor. 
         FIG. 7  is a schematic illustrating an environment of a monitor for activating a jawbone distractor of a jawbone distraction system of the present invention. 
         FIG. 8  illustrates an example of GUI of a monitor of a jawbone distraction system of the present invention. 
         FIG. 9  is a flow chart for controlling a micro-actuator by forward and reverse direction keys in a jawbone distraction system of the present invention. 
         FIG. 10  shows an example of flow chart for outputting a shifted image of a jawbone distractor from a monitor of a jawbone distraction system of the present invention. 
     
    
    
     BEST MODE 
     Hereinafter will be described a jawbone distraction system and a control method thereof with reference to the accompanying drawings. 
       FIG. 1  is a schematic illustrating a jawbone distraction system of the present invention, including a jawbone distractor  10 , a bone distraction monitor  20 , and a remote controller  30 , in which the remote controller  30  may be omitted. 
     The jawbone distractor  10  is composed of an upper bone support  100  and a lower bone support  200 , acting means for separating (isolating) or combining an upper bone to which the upper bone support  100  is installed, and a lower bone to which the lower bone support  200  is installed. That is, in the jawbone distractor  10 , the upper bone support  100  is installed under the ear of the upper jawbone, the lower bone support  200  is installed at the lower jawbone, connected with the upper jawbone, an actuator control signal transferred by the bone distraction monitor  20  or the remote controller  30  which is located at the outside is received at an actuator controller  350  to generate an actuator drive signal for controlling a micro-actuator  300  to be driven. Then, the micro-actuator  300  functions to separate (isolate) in a predetermined interval, or combine the upper jawbone to which the upper bone support  100  is installed, and the lower jawbone to which the lower bone support  200  is installed. 
     Although  FIG. 1  shows an example that the jawbone distractor  10  is set between the upper jawbone and the lower jawbone which is connected with the upper jawbone, the jawbone distraction system of the present invention may not be limited thereto in implementation and rather applicable to various modes of bone distraction such as alveolar bone. 
     The bone distraction monitor  20  functions to generate the actuator control signal through an arithmetic process with a degree of isolation between the upper and lower bones and then wirelessly transmits the actuator control signal to the jawbone distractor  10 . 
     According to circumstances, the bone distraction monitor  20  can also display an image signal (e.g. supersonic image signal, X-ray image signal) which is transferred by taking a picture of installation state of the jawbone distractor  10  of a patient from image devices. 
     The jawbone distractor  10  receives the actuator control signal from the bone distraction monitor  20  or the wireless remote controller  30  and then generates the actuator drive signal to control the micro-actuator  300  to be driven, making the upper and lower bones keep in isolation with a predetermined interval. The jawbone distractor  10  also wirelessly transmits information about a driving state of the micro-actuator  300  and an isolation state of the upper and lower bones, toward the bone distraction monitor  20 . 
     The remote controller  30  is a remote controller to enhance the mobility of doctor, partly including a function of the bone distraction monitor, which may be omitted in case. The remote controller  30  generates the actuator control signal from arithmetic process with a degree of isolation between the upper and lower bones, and wirelessly transmits the actuator control signal to the jawbone distractor  10  and the bone distraction monitor  20 . 
       FIG. 2  is a schematic illustrating appearances of a jawbone distractor according to an embodiment of the present invention, including the upper bone support  100 , the lower lone support  200 , a support rod  130 , a support rod fixer  190 , the micro-actuator  300 , and the actuator controller  350 . 
     The upper bone support  100  is a support to be installed at the upper bone, being formed of an actuator insertion unit  110  and an upper bone connector  120 . 
     The actuator insertion unit  110  is means for inserting the micro-actuator  300  into the center of the upper bone support  100 , including the upper bone connector  120  at the outer left and right sides. The actuator insertion unit  110  is fixedly installed the support rods  130  by combination between bolts, which are formed at one ends of the support rods  130  at the inner left and right sides, and nuts of support rod fixing holes  135 . The actuator insertion unit  110  has a nut portion  160  in the center. Into the nut portion  160  is inserted a bolt portion  310  of a shaft of the micro-actuator  300 . 
     The upper bone connector  120  is means for installing the upper bone support  100  at the upper bone. The upper bone connector  120  includes a fixing hole  140  for settling a fixing tool such as screw. 
     The lower bone support  200  is a support installed at the lower bone, which is formed of an actuator installation unit  210  and a lower bone connecter  220 . 
     The actuator installation unit  210  is means for fixedly installing the micro-actuator  300  at the center of the lower bone support  200 , including the lower bone connector  220  at the outer left and right sides. In the actuator installation unit  210 , the support rod  130  passes support rod passage holes  280  at the inner left and right sides and the micro-actuator  300  is fixedly installed at the center. 
     The lower bone connector  220  is means for installing the lower bone support  200  at the lower bone, including fixing holes  240  for installing fixing tools such as screws. 
     The support rods  130  formed of two members are means acting as guide rails for the lower bone support  200  to which the micro-actuator  300  is installed, which are fixedly installed at the inner left and right sides of the actuator insertion unit  110  of the upper bone support  100 , passing the support rod passage holes  280  at the inner left and right sides of the actuator installation unit  210  of the lower bone support  200 , and separately fixed each other by the support rod fixer  190 . 
     The support rod fixer  190  is means for fixing one ends of the support rods  130  in a certain interval. Occasionally, the support rod fixer  190  may be integrated with the lower bone support  200 . 
     The micro-actuator  300  is an actuator movable upward and downward while its shaft having screw threads is rotating, which is settled at the actuator installation unit  210  of the lower bone support  200  and whose shaft is inserted into the nut portion  160  of the actuator insertion unit  110  of the upper bone support  100 . The micro-actuator  300  may be made up of a supersonic motor using piezoelectric ceramic. 
     The actuator controller  350  is means equipped with a circuit for controlling and driving the micro-actuator  300 , which is located, at a position not disturbing drive of the micro-actuator  300 , under the actuator installation unit  210  of the lower bone support  200  and over the support rod fixer  190 . The actuator controller  350  receives the actuator control signal which is transmitted by the bone distraction monitor  20  or the wireless remote controller  30  which is located at the outside, and then generates the actuator drive signal to control the micro-actuator  300  to be driven. Additionally, the actuator controller  350  wirelessly transmits information about a current driving state of the micro-actuator  300  and an isolation state between the upper and lower bones toward the bone distraction monitor  20 . 
       FIG. 3  illustrates an example of a micro-actuator according to an embodiment of the present invention. 
     The micro-actuator  300  of  FIG. 3  includes a piezoelectric ceramic pillar and a shaft. 
     The shaft is located at the center of the piezoelectric ceramic pillar, including screw threads, and configured to move up and down while rotating. The piezoelectric ceramic pillar includes a cover enclosing its outside. To an outside of the cover is connected a signal transfer line  309 . 
     The micro-actuator  300  may be used with a supersonic motor employing a piezoelectric ceramic and configured to make the shaft, which has male screw threads, move up and down while rotating. 
       FIG. 4  is a schematic illustrating a configuration for driving a jawbone distraction system of the present invention, including the jawbone distractor  10 , the bone distraction monitor  20  and the remote controller  30 . 
     The jawbone distractor  10  includes the actuator controller  350  and the micro-actuator  300 , and the actuator controller  350  includes a transceiver  310 , a microcontroller  320 , an actuator driver  330 , an actuator state detector  340  and a shift detection sensor  345 . 
     The microcontroller  320  receives the actuator control signal from the monitor  20  or the remote controller  30  and then outputs the actuator control signal to the actuator driver  330 . The microcontroller  320  receives a state detection signal of the actuator from the actuator state detector  340  and transfers the state detection signal to the monitor  20  through the transceiver  310 , and transfers a shift detection signal to the monitor  20  through the transceiver  310  from the shift detection sensor  345 . 
     Here, it is permissible to employ an I2C interface for controlling a driver IC, i.e. the microcontroller  320 . The microcontroller  320  may use a host, i.e. an embedded system microcontroller that is workable in the I2C interface and the serial interface RS-232C with the monitor  20 . 
     The actuator driver  330  functions to drive the micro-actuator  300  in response to the actuator control signal which is received from the microcontroller  320 . 
     The driver for driving the micro-actuator  300  (e.g. piezoelectric motor) of MAGD has a DC-DC step-up converter as shown in  FIG. 5 , driving a half bridge driver in a form of phase-shifted square wave with a supersonic frequency required by the piezoelectric motor. 
     The actuator state detector  300  is means for ascertaining a motion of the actuator and the actuator detection signal may be composed of a detection signal with a voltage of a device serially coupled to the micro-actuator  300  or with a current of a signal input node of the micro-actuator  300 . 
     The shift detection sensor  345  functions to detect whether the lower bone support  200  has shifted (or detect a shift distance) and the shift detection signal which is detected is transmitted to the monitor  20  through the transceiver  310 . The shift detection sensor  345  may be a photo sensor, an infrared sensor or a resistive sensor. The shift detection sensor  345  may be omitted otherwise. 
     The micro-actuator  300  may use an USM motor or a piezoelectric motor. A function of the piezoelectric motor can be accomplished in a circuit adjusting a velocity along a progressing direction by means of a signal period and a duty ratio according to a pulse width modulation (PWM) signal and controlling a direction by means of a phase difference between electric signals connected to a plate. 
     The monitor  20  is means for monitoring a driving state of the jawbone distractor  10 , including a transceiver  410 , an arithmetic processor  420 , a memory  430 , a key input unit  440  and a display unit  450 . 
     The arithmetic processor  420  checks a driving state of the micro-actuator  300  from the actuator state detection signal which is received from the jawbone distractor  10  by way of the transceiver  410  and outputs a signal of the state signal to the display unit  450 . 
     The arithmetic processor  420  can receive a forward or reverse drive signal from the key input unit  440 , and then generate the actuator control signal and transmit the actuator control signal to the jawbone distractor  10  through the transceiver  410 . The arithmetic processor  420  otherwise can receive a forward or reverse drive signal from the remote controller  30  through the transceiver  410 , and then generate and transmit the actuator control signal to the jawbone distractor  10  through the transceiver  410 . The actuator control signal can be generated directly from the remote controller  30 , not from the arithmetic processor  420 . 
     Additionally, the arithmetic processor  420  receives the shift detection signal through the transceiver  410  from the jawbone distractor  10 , obtains a shift distance of the micro-actuator  300 , and outputs a value of the shift distance to the display unit  450 . The arithmetic processor  420  can otherwise output the shift detection signal to the display unit  450  to represent, on a preliminarily stored image (e.g. X-ray image), that a lower bone support connection is shifting in response to the shift detection signal. The arithmetic processor  420  can also estimate a rotation count of the motor from the actuator control signal and obtain a shift distance of the micro-actuator  300  from the rotation count of the motor. 
     The memory  430  stores an output of the arithmetic processor  420 , i.e. the shift distance of the micro-actuator  300 . 
     The key input unit  330  can include a shift start key, a shift end key, a forward shift key, a reverse shift key and so on. 
     The display unit  450  can output an output of the arithmetic processor  420 , i.e. the shift distance of the micro-actuator  300 , in a form of image or graph. 
     The remote controller  30  is means for wirelessly controlling the micro-actuator  300 , including a transceiver  510 , a microcontroller  520  and a key input unit  540 . The remote controller  30  can directly shift the micro-actuator  300  in the forward or reverse direction, or shift the micro-actuator  300  in the forward or reverse direction by way of the monitor  20 . 
     The key input unit  540 , including the forward shift key and the reverse shift key, inputs a key to shift the micro-actuator  300  in the forward or reverse direction. 
     The microcontroller  520  can transmit a forward shift signal or a reverse shift signal to the monitor  20  or the jawbone distractor  10  through the transceiver  510  from the key input unit  540 . 
     Otherwise the microcontroller  520  can generate the actuator control signal in response to the forward or reverse shift signal and then the actuator control signal to the jawbone distractor  10  through the transceiver  510 . 
     For motion control of MAGD and a wired remote control of position control command in the jawbone distraction system of the present invention, application software for host, i.e. a control program of the monitor  20 , can be composed using C/C++ and API, as shown in  FIG. 7 , and then transfer control commands and parameters through the RS-232C serial interface. 
     As a GUI (Graphical User Interface) of a host computer for MAGD control, the monitor  20  is configured as shown in  FIG. 8 , capable of conducting MAGD control with numerical control by simple mouth input unit and keyboard input. With respect to the MAGD control, it is permissible to prepare three regions of JOG Control, RUN Control and STEP Control so as to accomplish each parameter control. 
     The JOG Control enables the MAGD to be shifted in the reverse or forward direction by clicking Rev or Fwd. Only when Rev or Fwd button is being pressed down, the MAGD shifts. 
     The RUN Control enables the MAGD to be shifted in the reverse or forward direction by clicking Rev or Fwd. Only when button Stop is being pressed down, the MAGD stops. 
     The STEP Control sets Mtr Steps (motor step), Interval (shift distance interval) and Duration (shift time period). 
     Into box Mtr Steps, the number of steps is input to shift the MAGD. MAGD steps are driven by a burst signal (up to 65535). 
     Into box Interval, a value of ms is input in correspondence with each burst interval (104 ms). 
     Into box Duration, a period of each burst (ms) is input. This number must be smaller than the value of Interval and may be shorter than 1 ms. 
     Once the step parameter of the MAGD is set, clicking Rev or Fwd can shift the MAGD in the reverse and forward direction. 
     In the present invention, the microcontroller  320  of the actuator controller  350  switches a Half-Bridge FET switching device, which is embedded in a drive device for controlling the micro-motor, for MGAD control, if a control parameter command is received from the monitor  20  that is a PC host computer. During this, switching rate control is performed in the manner of PWM (Pulse Width Modulation) to determine the maximum power supply time, a rotor speed and torque of the micro-motor. 
       FIG. 9  is a flow chart for controlling a micro-actuator by forward and reverse direction keys in a jawbone distraction system of the present invention. 
     The flow chart of  FIG. 9  shows the procedure of setting a period and an interval step of a PWM wave in response to a key (Distraction Key) in MAGD drive parameter control algorithms and carrying out PWM control by means of an internal counter and an interrupt. 
     In an initializing step, if the forward and reverse direction keys begins to be driven, Mtr Steps (motor step), Interval (shift distance interval) and Duration (shift time period) are set and the counter is reset (S 110 ). 
     In a power factor clear step, a power factor goes to ‘0’ (S 115 ). 
     In an interrupt enable step, an interrupt flag of the microcontroller is forced to be set to an enable state, which makes an interrupt activated any time (S 120 ). The interrupt enable step can wait for until the disabled interrupt flag is enabled or forcibly reset the interrupt flag. 
     In a key input determination step, it is determined whether a key has been input into the key input unit (S 125 ). 
     In a processing step when there is no key input, if there is no key input into the key input unit, the counter is reset (S 130 ) and then it is determined whether a stop mode is present (S 135 ). If the stop mode is not present, a power factor is stored as a preset minimum power factor value (S 140 ), and the actuator controller turns off the actuator control (PWM control) (S 145 ), and reduce the stored power factor value (by one) (S 150 ). 
     In a power factor determination step (namely, a determination step to find out that the power factor is ‘0’), it is determined whether a stored value of the power factor is ‘0’ (S 155 ). If the power factor value is ‘0’, the procedure is terminated. If not, the procedure returns to the power factor clear step S 115 . 
     If a key has been applied to the key input unit in the key input determination step S 125 , the interrupt occurs to determine whether the interrupt flag is disabled (S 170 ). If the interrupt flag is disabled, the procedure returns to the interrupt enable step S 120 . 
     In a pulse on-time determination step (namely, a determination step to find that a pulse on-time is ‘0’), it is determined whether the pulse on-time is ‘0’ (S 175 ). If the pulse on-time is set on ‘0’, the procedure returns to the power factor clear step S 115 . 
     Generally, a PWM control signal is a signal formed in a pulse train with periods that repeats High and Low states, where the High state is represented as on and the Low state is represented as off. 
     In a counter value determination step, if the pulse on-time is not ‘0’ at the pulse on-time determination step (S 175 ), the counter value is read and compared to the pulse on-time and one period (total time) S 180 . 
     In a determination step of pulse on-time &lt; counter value ≦ one period, if the counter value is found as larger than the pulse on-time and smaller than one period (total time) at the counter value determination step S 180 , it is determined whether the stop mode is present (S 185 ). If not the stop mode, the power factor is set to the preset minimum power factor value (S 190 ), the actuator controller turns off the actuator control (PWM control) (S 195 ), the stored power factor value is reduced (by one) (S 200 ) and the procedure returns to the power factor clear step S 115 . 
     In a determination step of a counter value &gt; one period or a counter value ≦ pulse on-time, if the counter value is found as larger than one period (total time) at the counter value determination step S 180 , the counter is reset (S 210 ) and it is determined whether the start mode is present (S 215 ). If the start mode is present, the power factor is stored as the preset maximum power factor value (S 220 ), the stored power factor value is increased by one (S 225 ), the actuator controller begins (turns on) the actuator control (PWM control) (S 230 ) and the procedure returns to the power factor clear step S 115 . 
       FIG. 10  shows an example of flow chart for outputting a shifted image of a jawbone distractor from a monitor of a jawbone distraction system of the present invention. 
     In an X-ray image loading step, the arithmetic processor  420  of the monitor  20  reads a preliminarily stored X-ray image (S 510 ). Here, the stored X-ray image is an X-ray image after installing the jawbone distractor. 
     In a shifter setting step, a shifter in which the lower bone support is installed is set (S 515 ). It is possible to automatically calculate the set of the shifter, in which the lower bone support is installed, using an image. Otherwise a value established by a user through GUI can be loaded into the arithmetic processor  420  and used therein. 
     In a normal operation determination step, it is determined by comparing a preliminarily stored reference signal with an actuator state detection signal that is received from the jawbone distractor  10  whether the operation of the actuator is a normal state (S 520 ). If it is not the normal state, an alert informing an abnormal state is output to a speaker (not shown) or the display unit  450  (S 525 ) and the procedure is terminated. 
     In a shift detection signal reception step, if it is found as the normal state at the normal operation determination step S 520 , the shift detection signal is received from the jawbone distractor (S 530 ). 
     In a shifter shifting step, the shifter in which the lower bone support is installed is shifted in response to the shift detection signal on the X-ray image (S 540 ). 
     In a jawbone distractor drive end determination step, whether the jawbone distractor  10  stops driving is determined by the actuator control signal generated from the arithmetic processor  420  of the monitor  20 , or the actuator state detection signal or the shift detection signal received from the jawbone distractor  10  (S 550 ). If the jawbone distractor  10  stops, the arithmetic processor of the monitor  20  is terminated thereby. If the jawbone distractor  10  is still not stopped, the procedure returns to the normal operation determination step S 520 . 
     The above-disclosed subject matter is to be considered illustrative, and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other embodiments, which fall within the true spirit and scope of the present invention. Thus, to the maximum extent allowed by law, the scope of the present invention is to be determined by the broadest permissible interpretation of the following claims and their equivalents, and shall not be restricted or limited by the foregoing detailed description. 
     INDUSTRIAL APPLICABILITY 
     The present invention is concerned with a jawbone distraction system and a control method thereof, applicable to surgical treatments for deformed maxillofacial disorder patients and defective patients.