• 대한치과보철학회지
• /
• 제33권4호
• /
• pp.718-730
• /
• 1995

This study was performed to measure the mandibular movement and the changes of masicatory and sternocleidomastoid muscle activity reflected by occlusal disturbance during habitual chewing. For this study, 18 subjects(14 males and 4 females with an average age of 24.0) were selected. The impression of each subject were taken for measuring intermolar distance on lower dentition. The activities of masticatory and sternocleidomastoid muscle and the mandibular movement were recorded and analyzed during habitual chewing by means of E.M.G.(electromyograph), E.G.N.(electrognathograph), rotate program in BioPak analyzing system(BioResearch Inc.). The results were as follows : 1. In EMG of the mandibular rest position, the mean value of muscle activites were increased by nocleidomastoid muscle and anterior belly of digastric muscle(0.05

• 대한치과교정학회지
• /
• 제20권1호
• /
• pp.47-59
• /
• 1990

Respiration is one of the most important functions which are carried out in stomatognathic system. When nasal orifice is obstructed or the resistance of upper airway is increased mouth breathing is initiated. Mouth breathing is regarded as an important etiologic factor of dentofacial anomalies. This experiment was performed to observe the influences of metabolic acidosis, tracheal resistance and vagotomy on mouth breathing. After rabbits were anesthetized with sodium pentobarbital, a pair of wire electrode was inserted into mylohyoid muscle, anterior belly of digastric muscle and dilator naris muscle to record EMG activity. Femoral vein and artery were cannulated for infusion of 0.3N HCl and collection of blood sample to determine the blood pH, and tracheal intubation was done to control airway resistance. Mouth breathing was induced by metabolic acidosis. Increase of the airway resistance through tracheal cannula intensified the activity of dilator naris, mylohyoid and digastric muscle. The higher the resistance, the larger the EMG amplitude. After bilateral vagotomy, respiratory volume and inspiatory time were increased and the activities of dilator naris, mylohyoid and digastric muscle were strengthened. It was concluded that the muscle activity related to mouth breathing was induced by metabolic acidosis and increase of tracheal tube resistance.

• Restorative Dentistry and Endodontics
• /
• 제29권3호
• /
• pp.226-232
• /
• 2004

Use of electric pulp testing elicits painful response in vital teeth. In this study, we examined the excessive time from pain feeling to stimulation disconnection in clinical situation. D626D (Parkell Inc., USA.) scan type electric pulp tester was used in total of 23 young healthy individuals. Each of the right central incisors and first premolars were used as testing teeth. Stimulation disconnection was achieved by EMG in anterior belly of digastric muscle, finger span, and voice and the excessive stimulation time over the sensory thresh-old was recorded. As a result, we found that the short responses before the stimulation disconnection appeared following order：EMG, finger span, and voice. The EMG disconnection is suggested to be used to reduce the excessive stimulus time in electric pulp testing.

• 치과방사선
• /
• 제22권1호
• /
• pp.29-37
• /
• 1992

The temporomandibular joint was evaluated using magnetic resonance imaging using a urface coil in 11 patients having reciprocal clicking or locking and compared with the normal joint in five subjects. Serial multisection 3㎜-thick parasagittal, paracoronal, and axial image on both closing and opening mouth were obtained with a 1.5 Tesla MR system and surface coil using CSMEMP, GRASS, MPGR, powerful extensions of fast imaging that is currently under clinical evaluation. MR images obtained were analized correlating with the theory of internal derangement. The obtained results were as follows: 1. The serial findings of structures in joint were determined on the serially sectioned images of joint with reciprocal clicking or locking by CSMEMP and MPGR on closing mouth. 2. The delta shaped white images of synovial fluid in the glenoid fossa and on the posterior surface of condyle were revealed on the parasagittal images by MPGR on opening mouth as in the normal joints. 3. The white image of joint fluid surrounding meniscus was recognized on the paracoronal image by GRASS on opening mouth as in the normal joints. 4. In joints having temporomandibular dysfunction the smooth image of displaced meniscus was recognized, but otherwise in the normal joints the image of muscle was noted on the paracoronal image sectioned at the anterior portion of condyle by GRASS. 5. The more thickened fascial plane between superior and inferior belly of lateral pterygoid muscle was not recognizable in joints having temporomandibular dysfunction than in the normal joints.

• 대한소아치과학회지
• /
• 제23권3호
• /
• pp.717-728
• /
• 1996

The effects of electro-acupuncture on the pain threshold and the amplitude of dEMG(di-gastric EMG) evoked by the noxious electric stimulation on teeth and gingiva in dogs were studied. Experiments were carried out with 10 dogs weighing 5-8kg. Each animal was anestheticed with Entobar given intraperitoneally in an initial dose of 30mg/kg. Maintenance dose of 5mg/kg/hr was given through a cannula, in the femoral vein, as required to keep up light anesthesia. Bipolar stimulating wire electrodes, 0.1mm in diameter, insulated except for tips, were inserted into the upper canine and palatal gingiva. Rectangular aluminium plate electrodes (15$\times$5mm) were placed on acupuncture points, called Yin-Hsiang, located at both sides of the upper jaw. Rectangular biphasic current pulses of 2Hz, with a $250{\mu}sec$ duration, were delivered for 15 minutes. The dEMG activities were recorded from the anterior belly of the digastric muscle(one of the jaw opening muscles) using bipolar wire electrodes. The magnitude of the jaw opening reflex at different intensties of electro-acupuncture(1volt 4volt and 10volt) was estimated by averaging the 30 superimposed dEMGs recorded on an oscilloscope and audiomonitor. Data were analysed statistically with ANOV A and paired t-test. The obtained results were as follows: 1. Pain thresholds were increased 7.7 %, 15.4 %, 17.3 % in the teeth and 11.1 %, 19.0 %, 25.4 % in the gingiva as the intensities of electro-acupuncture increased incrementally. 2. Amplitudes of dEMG were decreaed 8.3%, 22.4%, 27.4% in the teeth and 9.8%, 36.5%, 42.2 % in the gingiva as the intensities of electro-acupuncture increased incrementally. 3. Inhibition of pain responses by the electroacupuncture was more effective in the gingiva than in the teeth.

• 대한소아치과학회지
• /
• 제23권2호
• /
• pp.525-536
• /
• 1996

The purpose of this study was to investigate the effect of electrical anesthesia induced by non-acupuncture point stimulation on inhibition of amplitude of digastric EMG evoked by noxious electrical stimuli in teeth and gingiva. Experiments were performed with dogs anesthetized with intraperitoneal pentobarbital sodium in an initial dose of 30mg/kg. Maintenance doses of 4.0ml/hour were given through a cannula in the femoral vein using a constant infusion pump. Anterior belly of digastric muscle was exposed and a pair of 0.1mm wire electrodes were inserted for E.M.G. recording. Bipolar electrodes were inserted into the labial and lingual surface of upper canine and the labial area of upper gingiva. Noxious stimuli were delivered to the tooth and gingiva through those electrodes by electric stimulator. Non-acupuncture point stimulation of 2Hz was delivered bilaterally to the femoral area. Amplitudes of digastric E.M.G. were measured from the oscilloscope and the monitor connected to amplifier at different intensities of electronic anesthesia of 1 volt, 4 volt and 10 volt. The inhibited rate of the amplitudes of digastric E.M.G. were analysed statistically with paired t-test. The following results were obtained : 1. Non-acupuncture point stimulation with intensities of 1 volt, 4 volt and 10 volt showed the inhibitory effect on pain of 15%, 25% and 16% in teeth and 15%, 18% and 12% in gingiva respectively 2. In tooth, statistical significance was observed between control and each group. In gingiva, there was statistical significance between control and group 1, 2 except group 3 From these results, low frequency electrical stimulation of non-acupuncture point resulted in reducing of dental and gingival pain, it could be used as adjunct to other pain control methods.

• 전자공학회논문지SC
• /
• 제41권6호
• /
• pp.43-49
• /
• 2004

치수 검사(pulp test)는 치아에 물리적 및 화학적 자극을 가하여 치수의 생활력(vitality) 여부를 판별하는 검사이다. 치과 임상에서 수행되는 검사 과정에서 피검자는 치아에 가해지는 역치 이상의 자극으로 인하여 큰 고통과 스트레스에 노출된다. 본 논문에서는 생활치수의 전기 치수 검사 시, 자극의 강도를 서서히 증가시켜 역치에 이르게 되면 나타나는 피검자의 동통반응으로 개구반사에 의한 악이복근의 근전도, 발성에 의한 음성 반응, 손가락의 움직임에 의한 반응을 각각 측정하였다. 또한 동통 반응이 발생하는 시점으로부터 자극이 차단될 때까지 피검자에게 필요이상으로 인가되는 과용 자극 시간을 측정하였으며, 과용자극 시간 측정 시 치수 검사기의 자극 차단 주체자에 따른 과용 자극 시간을 측정 분석하였다. 이러한 결과를 바탕으로 동통 반응에 의한 인체 반응 신호를 이용하여 치수검사기의 출력을 자동으로 차단하는 제어 스위치를 구성하였다. 피검자가 역치 자극을 느낀 후 나타나는 최초의 인체 반응의 10 ms 이내에 신속하게 검사기의 출력을 차단함으로써 과용자극 시간을 줄이고자 하였다.

• 대한치과교정학회지
• /
• 제24권3호
• /
• pp.569-586
• /
• 1994

성장기 백서에 있어서 상악 및 하악 절치의 제거와 soft diet 투여시에 있어서 하악과두의 후상부와 상부에서의 연골의 성장, 연골층의 두께 및 미세구조 그리고 교근의 천층 및 악이복근의 근섬유에 미치는 영향을 요약하면 다음과 같다. 과두연골의 후상부 및 상부에서, 섬유층과 증식층의 두께가 대조군에 비해 유의하게 감소하였으며(p<0.01), 후상부에서의 감소정도는 상부보다 컸었다. 그러나 성숙세포층, 비대세포층 및 연골 전체의 두께는 대조군에 비해 차이가 없었다. $^3H-thymidine$투여 후 시간경과에 따른 각 층의 세포표지율은 상부에서는 대조군에 비해 차이가 없었으나 후상부에서는 투여후 1일과 2일 경과군에서는 성숙세포층, 4일 경과군에서는 비대세포층의 표지율이 대조군에 비해 유의하게 감소하므로서 (p<0.01) 상악 및 하악 절치의 제거와 soft diet투여로 과두 후상부에 가해지는 기계적 부하의 감소로 인해 이 부위의 연골성장이 감소되는 것으로 나타났다. 대조군에 있어서, 하악과두는 상부에 비해 후 상부방향으로 더 빨리 성장하는 것으로 나타났다. 교근의 천층에서, type IIA 근섬유의 직경은 변화하지 않았으나 type IIB 근섬유의 직경은 대조군에 비해 유의하게 감소하였다 (P<0.01). 악이복근의 전복에서, type I 근섬유의 직경은 변화하지 않았으나 type IIA, type IIB 근섬유의 직경은 대조군에 비해 유의하게 감소하였다(P<0.01). 하악과두 연골의 미세구조에 있어서는 증식층, 성숙세포층 및 비대세포층은 모두 후상부와 상부에서 대조군에 비해 유의할 만한 변화가 없었다. 그러나 섬유층에서, 상부에서는 대조군에 비해 차이가 없었으나 후상부에서는 뚜렷한 차이가 있었다. 실험군 후상부의 섬유층에서는 대조군처럼 관절강에 인접한 세포와 증식층에 인접한 세포사이의 미세구조적 차이는 인지되지 않았으며, 흡수기능을 가진 세포에서 보이는 손가락 모양의 많은 세포돌기, 세포막을 따라 나타나는 수 많은 미음소포, 발달된 용해소체, 사립체 그리고 불규칙한 모양의 핵 등과 같은 대조군의 관절강에 인접한 세포에서 많이 나타나는 특징은 미약하였으며 전반적으로 세포간 기질을 개조하는 활동이 감소하는 양상을 보였다.

• 대한소아치과학회지
• /
• 제25권4호
• /
• pp.788-796
• /
• 1998

The purpose of this study was to investigate the effect of various electroacupuncture duration induced by acupuncture point-Zusanli ($S_{36}$) electrical stimulation on inhibition of amplitude of digastric electromyogram (dEMG) evoked by noxious electrical stimuli around the mental foramen. intraperitoneal sodium pentobarbital in an initial dose of 50mg/kg and maintenance doses of 4.5mg/kg/h were given through a cannula in the femoral vein using a constant infusion pump. A pair of stimulating electrodes were inserted for noxious stimuli around the mental foramen. An irritant electronic stimuli pulse (0.2 Hz, 0.1 ms duration) was produced with an intensity of about $1.5{\times}2$ times threshold for evoking the dEMG. The anterior belly of the digastric muscle was exposed and a pair of 0.1mm wire electrodes were inserted for dEMG recording. Acupuncture point stimulation on Zusanli (2 Hz, 250 ${\mu}s$, biphasic pulse, 2 V) was delivered by Dental Electronic Anesthesia (3M, U.S.A). For periods of electronic stimulation of 10, 20, and 30min, the amplitudes of dEMG were measured on the oscilloscope and on the monitor connected to the amplifier. The following results were obtained: The dEMG was decreased to 73.4% of that in the control set after 10 min electroacupunture stimulation (Group I); The dEMG was decreased to 77.1% (10min), 54.0.% (20min) of that in the control set after 20minutes of electroacupunture stimulation (Group II). The dEMG was decreased to 73.3% (10min), 61.9% (20min), 76.2% (30min) of that in the control set after 30 min of electroacupunture stimulation (Group III). From these results, it may be that in the electroacupuncture stimulation on the Zusnali resulted in a reduction of amplitude of dEMG and that the most effective electroacupuncture stimulation period was 20min.

• 한국전문물리치료학회지
• /
• 제18권4호
• /
• pp.60-67
• /
• 2011

Ultrasonography (US) is a recent technique that has proven to be useful for assessing muscle thickness and guiding the rehabilitation decision-making of clinicians and researchers. The purpose of this study was to determine the inter-rater reliability of the US measurement of transversus abdominis (TrA), internal oblique (IO), and external oblique (EO) thicknesses for different probe locations and measurement techniques. Twenty healthy volunteers were recruited in this study. Muscle thicknesses of the transversus TrA, IO, and EO were measured three times in the hook-lying position. The three different probe locations were as follows: 1) Probe location 1 (PL1) was below the rib cage in direct vertical alignment with the anterior superior iliac spine (ASIS). 2) Probe location 2 (PL2) was halfway between the ASIS and the ribcage along the mid-axillary line. 3) Probe location 3 (PL3) was halfway between the iliac crest and the inferior angle of the rib cage, with adjustment to ensure the medial edge of the TrA. The two different techniques of thickness measurement from the captured images were as follows: 1) Muscle thickness was measured in the middle of the muscle belly, which was centered within the captured image (technique A; TA). 2) Muscle thickness was measured along a horizontal reference line located 2 cm apart from the medial edge of the TrA in the captured image (technique B; TB). The intraclass correlation coefficient (ICC [3,k]) was used to calculate the inter-rater reliability of the thickness measurement of TrA, IO and EO using the values from both the first and second examiner. In all three muscles, moderate to excellent reliability was found for all conditions (probe locations and measurement techniques) (ICC=.70~.97). In the PL1-TA condition, inter-rater reliability in the three muscle thicknesses was good to excellent (ICC=.85~.96). The reliability of all measurement conditions was excellent in IO (ICC=.95~.97). Therefore, the findings of this study suggest that TA can be applied to PL1 by clinicians and researchers in order to measure the thickness of abdominal muscles.