• 대한치과보철학회지
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• 제25권1호
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• pp.213-226
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• 1987

The purpose of this study was to standardize and classify the coordination pattern among the left and right masseter and anterior temporal muscles, in terms of integrated EMG values per stroke during gum chewing in normal subjects. In this study, 20 normal subjects were selected to chew a piece of gum and integrated EMG from middle portion of the masseter and anterior temporal muscles on both sides were recorded 20 times during each of the right and left chewing respectively. And the Bioelectric Processor Model EM2 (Myo-tronies Research, Inc., U.S.A.) with the surface electrodes was used to record the EMG activity during all experimental procedures. The results were as follows; 1. In all subjects, the chewing side masseter muscle was predominantly active among the four muscles examined. 2. The integrated EMG value of the middle of masseter muscle was significantly predominant than those of the anterior temporal muscle (p<0.0001) on the chewing side, but no significant predominant was observed on the nonchewing side (p<0.98). 3. In comparison with same muscles on the chewing and nonchewing side, low correlation coefficient was found between the middle of masseter muscles (R=0.317), but high correlation coefficient was found between the anterior temporal muscles (R=0.738). Between two muscles on the same side, there were significant correlation in the chewing (R=0.557) and nonchewing side (R=0.625). 4. In the coordination patterns among four muscles examined, distinct individual differences were found, but in an identical subject one fixed pattern appeared with significant reproducibility.

• 치위생과학회지
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• 제12권1호
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• pp.45-53
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• 2012

본 연구는 각종 구취제거방법 중 효과적인 방법들을 시행하여 효율적인 구취제거 방안을 마련하고자 시행하였다. 2007년 4월 2일부터 2007년 4월 13일까지 서울 S보건대학 치위생과 재학생 중 만 20세에서 22세의 여학생 17명을 대상으로 실시하였다. 실험대상자는 구취제거방법을 시행하지 않은 대조군, 잇솔을 사용한 잇솔질군, 구강위생보조용품인 혀세정기구 사용군, 사탕섭취군(무설탕), 껌 저작군(무설탕)으로 분류하였다. 이를 통하여 구취감소를 측정하고 비교 분석하여 다음과 같은 결과를 얻었다. 1. 대조군과 실험군의 구취는 시간이 경과함에 따라 실험 20분 경과까지 통계적으로 유의하게 감소하였다(P<0.05). 2. 잇솔질군의 구취는 대조군에 비하여 실험 5분 경과부터 실험 20분에 이르기까지 통계적으로 유의하게 낮게 나타났다(P<0.05). 3. 혀세정기구 사용군의 구취는 잇솔질 사용군에 비하여 통계적으로 유의한 차이를 보이지 않았다(P>0.05). 4. 사탕섭취군의 구취는 실험 5분 경과에서 대조군과 유의한 차이를 보였다(P<0.05). 5. 껌 저작군은 저작 후 10분 경과까지 대조군과 차이를 보이며 통계적으로 유의하게 낮게 나타났다(P<0.05).

• 한국치위생학회지
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• 제11권6호
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• pp.853-862
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• 2011

Objectives : The aim of this study was to investigate the number of self-report symptoms for temporomandibular disorders(TMD) and related factors in the third grade students of high school. Methods : A total of 1,043 high school the 3rd students age 16 20 completed a questionnaire from 11 high schools in Andong city from April to June 2010. Student's t-test was used to analyze the difference of TMD number. Multiple regression analysis was performed to determine the effects of independent variables on TMD number. Results : 1. Students who have one TMD were 71.3%, two 41.7% and over three 25.7%, respectively. 2. The number of TMD symptom of students who have no good habits such as clenching, bite lip and cheeks, resting on hand, chewing gum, hard foods, and unilateral chewing was a statistically significant higher than those who doesn't have ones(p=0.00). 3. TMD number of students who have been under more stress was a significantly higher than those who didn't have been(p=0.00). 4. Bite lip and cheek(${\beta}$=0.03, p=0.037), chewing gum(${\beta}$=0.03, p=0.029), resting on hand(${\beta}$=0.04, p=0.006), hard foods(${\beta}$=0.07, p=0.000), and stress out(${\beta}$=-0.03, p=0.018) were significantly associated with TMD number by multiple regression analysis. Conclusions : Variables associated with TMD were bite lip and cheek, chewing gum, resting on hand, hard foods, and stress out factor. According to our findings, it is so important to teach good habits on oral health to the 3rd grade students in high school. Further prospective study should explore cause of TDM from those variables.

• 대한치과보철학회:학술대회논문집
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• 대한치과보철학회 1999년도 Asian Academy of Prosthodntics. Korean Academy of Prosthodontics
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• pp.33-33
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• 1999

• 대한치과의사협회지
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• 제48권6호
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• pp.436-442
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• 2010

Objective: Transmission of S. mutans, a major dental caries pathogen, occurs mainly during the first 2.5 years of age. Children appear to acquire S. mutans mostly from their mothers, but few studies have investigated preventive effect of xylitol to S. mutans transmission from mother to child. The aim of this study was to perform a follow-up evaluation the preventive effect of xylitol chewing gum of the S. mutans of children's oral cavities, which included the characteristics of vertical transmission from mother to child. Methods: The mothers voluntarily participating in a women's oral health prevention program were divided into two groups (a control and a xylitol group). The subjects were 20 mother-child pairs, who were monitored for 30 months. Xylitol chewing gum group had consumed 2 gum pellets, 3 times a day for 24 months, and then they were followed until 30 months. At baseline, 24 and 30 months whole stimulated saliva samples were collected from the mothers. Children were also recruited from 6 months to 30 months after birth and were collected their dental plaque samples. After isolation and identification, the analysis of the colony count, transmission electron microscopy and real-time RT-PCR were performed to analyze the characteristics of S. mutans. Results: The S. mutans counts decreased steadily in the xylitol group at 24 months, but increased at 30 months. The similar results were showed at their children. While the glucan synthesis was decreased at xylitol group both mother and child. The expression of gtfB, gtfD and ftf were significantly reduced in the xylitol group both mother and child (p<0.05). Conclusions: These findings indicate that chewing xylitol gum over a long period may decrease the expression of the genes associated virulence and reduced the glucan synthesis of S. mutans, which can result the preventing the mother-to-child transmission of S. mutans.

• 대한치과보철학회지
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• 제29권1호
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• pp.53-71
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• 1991

This study was performed to investigate the muscular activity of the complete denture wearers compare with subjects with natural teeth. For the study, 10 subjects with natural dentition and 18 upper and lower complete denture wearers selected and the Bio-electric Processor EM2(Myo-tronics Reaserch, Inc., U.S.A.) with the surface electrodes was used to record electromyographic activity from the right and left middle of masseter and anterior temporal muscles of each subject during mandibular postural rest position, tapping of teeth from postural rest position, maximal clench, and right and left gum and raw carrow chewing. This results of this study were as follows : 1. In mandibular postural rest position, the denture wearers produces high muscular activity in contrast to natural objects(P<0.05) but, there was no difference between the state of denture removal and insertion, and the muscle activity of the anterior temporal muscle was high than the middle of masseter muscle in natural objects and denture wearers. 2. In tapping of teeth, there was no difference in muscle activity between natural objects and the state of denture removal of denture wearers. 3. In maximal clench, there was markedly lower denture wearers than natural objects in muscle activity, and the ratio of mean voltages was about 36 percentages. 4. In gum and raw carrow chewing, the activity was lower than natural object, the ratio was about 59 percentages. 5. In chewing, the mean voltages of the middle of masster muscle on the chewing side was highest, followed by the anterior temporal on the chewing side, the anterior temporal and masster muscles on the non-chewing side.

• Journal of Oral Medicine and Pain
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• 제32권3호
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• pp.319-328
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• 2007

본 연구는 근육의 경도와 탄성도를 측정하여 교근 피로에 대한 물리치료의 효과를 정량적으로 평가하고자 하였으며, 측두하악장애 치료에 가장 흔히 사용되는 물리치료이면서 작용기전은 서로 다른 세 가지 치료법인 전기침자극치료(EAST), 극초단파(Microwave diathermy), 저수준레이저치료(LLLT)의 효과를 비교하였다. 실험을 위하여 건강한 20대 지원자 10명을 선정하여, 교근의 전부와 하부의 근육 경도와 탄성도를 촉각센서로 측정하였다. 실험적으로 교근 피로를 유발하기 위해 피검자가 VAS (0 to 10) 5 이상의 통증을 느낄 때까지 껌을 씹게 하여 근육 변화를 조사하였으며 치료 없이 15분간의 휴식을 준 다음 다시 검사하여 물리치료 후의 효과 비교를 위한 대조군으로 사용하였다. 하루 간격으로 사흘에 걸쳐 동일한 시간 동안 껌을 씹게 한 다음, 물리치료 한 가지씩을 매일 시행하였으며 3가지 물리치료법의 적용 순서는 무작위로 하였다. 껌 저작 전, 직후, 15분 후, 각각의 물리치료 시행 후에 근육 경도와 탄성도 측정과 함께 피검자들이 느끼는 근육의 피로도를 VAS로 평가 하도록 조사하였다. 실험 결과, 저작측에서만 껌 저작 직후와 15분 후에 근육경도의 증가와 탄성도의 감소가 관찰되었으며 (p<0.05) 비저작측에서는 유의한 차이가 없었으나 VAS는 저작측과 비저작측 모두에서 증가하였다(p<0.05). 껌 저작으로 인해 변화되었던 근육경도와 탄성도는 전기침자극치료나 극초단파 치료 후에 효과적으로 회복되고 VAS가 감소했으나(p<0.05) 저수준레이저 치료 후에는 유의한 변화를 보여주지 않았다. 이상의 결과로 보아, 편측 저작은 저작측 근육의 경도를 증가시키고 탄성도는 감소시키는 반면, 비저작측에서는 변화가 없는 것을 알 수 있다. 또한 전기침자극치료와 극초단파치료는 모두 근육의 경도를 감소시키고 탄성도를 증가시켜 근육의 피로를 감소시키는데 효과적인 치료법인데 반해 저수준레이저치료의 효과는 미약한 것으로 판단된다.

• 대한치과보철학회지
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• 제40권6호
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• pp.577-589
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• 2002

There are several variations in normal mastication. In them, unilateral mastication is chewing, predominantly on a preferred side of the dentition and hardly on e non-preferred side. Continual unilateral mastication may alter the coordination of masticatory muscles. Although they studied about these EMG of masticatory muscles, there were no information about characteristics of masticatory muscle activity in unilateral mastication. Therefore, In this study, we investigated the activity of the masseter and anterior temporal muscles during rest, clenching in maximum intercuspation and gum chewing in habitually unilateral mastication group compared with normal group and tried to know effects of continual unilateral mastication on activity of masticatory muscles. The results of this study were as follows 1. In electromyographic activity during rest, in bilateral mastication group pattern of muscle activity of right and left side was symmetrical. But, in unilateral mastication group, records of anterior part of temporal muscle was higher than that of bilateral mastication group (p<.01) and patterns of muscle activity of right and left side in both muscle were asymmetrical.(p<.05) 2. In electromyographic activity during clenching in maximum intercuspation, records of superficial part of masseter muscle were higher than anterior part of temporal muscle in both group. Muscle activity of temporal muscle in unilateral mastication group was a little higher han bilateral mastication group and asymmetry of activity pattern in temporal and masseter muscle was shown but these differences were not statistically significant. (p<.05) 3. In electromyographic activity during gum chewing, temporal muscle was activated earlier than masseter muscle and maximum bite force is derived from masseter muscle in both group. In unilateral mastication group, electromyographic activity of masseter and temporal muscle of preferred chewing side, regardless of right or left side chewing, was higher than that of bilateral mastication group and especially, difference in masseter muscle was statistically significant. (p<.01) Based on the above results, our study suggested that recording of masticatory muscle activity will be helpful in the effective diagnosis and treatment of some types of the parafunctional habits.

• Journal of Oral Medicine and Pain
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• 제46권4호
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• pp.155-160
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• 2021

The masticatory muscle disorder is the most common problem that patients with temporomandibular disorder often complain. For such complaints, treatment is directed towards reducing hyperactivity of muscles or effects of the central nervous system. However, if nonspecific occlusal change or pain persists, it is necessary to consider that muscle weakness might be the cause of the persistence of temporomandibular disorder. Stabilization of occlusion and improvement of the pain symptoms were achieved in both cases through the chewing gum exercise. This exercise may enable masticatory movements done in normal function by using muscle engram and achieve reinforcement of the masticatory muscles with balanced, simultaneous contacts of the teeth. In addition, it may be a viable method for treating temporomandibular disorders that do not respond well to conventional mandibular stabilization therapies.

• Journal of Oral Medicine and Pain
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• 제24권4호
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• pp.421-437
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• 1999

This study was performed to investigate the electromyographic(EMG) activity, firing time and sequence of the mandibular elevator muscle on gum chewing. For this study, 28 patients with temporomandibular disorders(TMD), especially internal derangement of TM joint, and 16 dental students without any signs and symptoms in the masticatory system were selected as the patients group and as the normal group, respectively. The patients group was composed of 14 right and 14 left side affected patients. For recording of EMG activity(${\mu}V$) of the anterior temporalis(TA) and the masseter muscle(MM), and measuring of firing time(millisecond) from the start of mandibular opening movement to the firing of the muscles, BioEMG, BioEGN, and Combo program integrated in the Biopak system(Bioresearch Inc., Milwaukee, USA) were used. Gum chewing stroke was performed in both right and left side for several times, and the first and the second chewing strokes were analysed and compared with regard to EMG activity, firing time, firing sequence, correlation between EMG activity and firing time. The data obtained were analysed by SPSS windows program and the results of this study were as follows : 1. In the patients group, chewing on the affected side showed higher EMG activities in the masseter of the side than those of the contralateral side, but chewing on the unaffected side showed higher EMG activity in the masseter and in the anterior temporalis of the side than those of the contralateral side. 2. There were no difference of firing time between both sides on chewing on the affected side, but firing time in the chewing side were earlier than that of contralateral side on chewing on the unaffected side in patients group. 3. In the normal group, EMG activities in the masseter and in the anterior temporalis in the chewing side were always higher than those of the contralateral side, and there were no difference of firing time between the two sides. 4. In general, firing sequence of four muscles of both sides were ipsilateral TA, ipsilateral MM, contralateral TA, and contralateral MM in earlier order of time in both groups. Correlation coefficients between EMG activity and firing time were negative value, and more significant correlation were appeared in the normal group than in the patients group.