• Journal of Oral Medicine and Pain
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• 제30권4호
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• pp.411-426
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• 2005

이갈이나 이악물기 시 근활성, 하악의 이동, 악관절에 가해지는 부하, 그리고 교합에 미치는 영향 등에 대한 연구는 많았으나 하악운동에 미치는 영향에 대해서는 연구가 적었다. 따라서 측두하악장애의 주요한 기여요인으로 간주되는 이악물기나 강한 씹기에 의해 나타나는 하악의 미세한 운동양태에 대해서는 더 많은 연구가 수행될 필요가 있으며, 이에 본 연구에서는 하악의 비틀림 회전운동을 중심으로 이악물기 및 강한 씹기의 영향을 조사하였다. 저작계 이상이 없는 건강한 남자 14명을 선정하여 교합고경 및 형태의 변화와 수의적 이악물기 수준의 차이가 이악물기 및 씹기 운동 시 나타나는 하악의 비틀림 회전운동(torque rotational movement)에 미치는 영향을 조사하였다. 각 교합조건과 이악물기 힘에서의 씹기 운동은 먼저 나무젓가락(분리기)이 없는 한 번의 이악물기와 나무젓가락을 구치부에 위치시킨 상태에서 두 번에 걸친 씹는 운동 등 세 번의 하악운동으로 구성되었다. 본 연구의 결론은 다음과 같다. 1. 좌측으로 씹을 때와 우측으로 씹을 때 간에 전두면 및 시상면상 운동거리는 두 가지 이악물기 힘 모두에서 차이가 없었으나 하악의 운동속도는 다른 양상을 보여 강한 이악물기에서는 차이가 없었으나 약한 이악물기에서는 좌측으로 씹을 때 우측에 비해 속도가 다소 빠른 경향을 보였다. 이때 하악의 비틀림 회전운동각은 두 가지 이악물기 모두에서 전두면상 차이는 거의 없었으나 수평면상 각도에서는 씹는 측에 따라 차이가 있는 경향을 보였다. 2. 이악물기 힘의 차이는 전두면 및 시상면상 운동거리와 속도에 영향을 미쳐 강한 씹기에서 약한 씹기에 비해 측정치가 크게 나타났으며 하악의 비틀림 회전운동각 역시 강한 씹기에서 수평면상 운동각이 다소 증가된 양상을 보였다. 3. 전두면 및 시상면상 개구거리는 교합조건에 따른 차이를 보였는데, 즉 웨이퍼나 레진블록 등 교합고경이 높은 교합형태일수록 운동거리가 감소하였으며, 이때 강한 씹기에서는 운동속도 역시 유사한 양상으로 감소하였다. 그러나 하악의 비틀림 회전운동각은 전두면 및 수평면 모두에서 교합조건에 따른 차이를 거의 나타내지 않았다. 4. 세 번의 씹는 운동에서 분리기가 없는 경우에 비해 있는 경우에서 대체로 전두면상 회전운동각을 제외한 나머지 하악의 비틀림 회전운동량은 모두 증가하는 양상을 보였다. 그러나 이때 각 교합형태 간 동일항목의 비교에서는 전두면상 회전운동거리가 이악물기 힘에 따른 차이를 보여 약한 이악물기에서 유의한 변화를 나타내었다. 이상의 연구를 통해 하악 비틀림 회전운동의 전체적인 양상은 관찰면에 따라 다르게 나타나 이악물기 힘에 따른 차이는 전두면에 비해 수평면상 측정치가 더 많이 변화되는 모습을 보였으나 교합조건에 따른 양상은 관찰면 간 차이를 보이지 않았다. 한편 이악물기 및 씹는 운동 각각에서의 하악 비틀림 회전운동량은 교합조건이나 이악물기 힘에 관계없이 대체로 분리기 씹기에 의해 수평면상 회전운동량의 변화가 전두면상 측정치에 비해 더 유의하게 나타났다.

• Journal of Oral Medicine and Pain
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• 제25권4호
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• pp.383-394
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• 2000

This study was performed to investigate the effect of change of body posture on the rest position and the rotational torque movement of the mandible. Thirty dental students without any signs and symptoms of temporomandibular disorders and with natural dentition were selected for this study. Cervical inclination and the amount of the mandibular movement on protrusion, on left and right excursion, and on tapping in three body postures such as sitting position, supine position without pillow, and supine position with pillow were measured by goniometer, Cervical-Range-of-$Motion^{(R)}$, and mandibular tracking device, $BioEGN^{(R)}$ with $Rotate!^{(R)}$ program. The data obtained were classified and processed according to body posture and type of lateral guidance with SPSS windows program and the results were as follows: 1. There was significant difference among the three cervical inclinations by body postures. 2. Comparison of mandibular rest positions among body postures showed significant difference only for lateral distance in frontal plane, but comparison between before and after swallowing showed significant difference except for the lateral distance, vice versa. 3. Distance and amount of the rotational torque movement on protrusion and/or lateral excursions didn't show any difference by body posture. But by both body posture and lateral guidance type, there were slightly significant difference for some items. 4. A significant difference was shown for the rotational torque movement in frontal plane on tapping by body postures, for the lateral distance in frontal plane on sitting position by lateral guidance type, and for the rotational torque movement in frontal plane by both body posture and lateral guidance type.

• Journal of Oral Medicine and Pain
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• 제23권2호
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• pp.143-155
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• 1998

This study was performed to investigate the factor that might affect mandibualr body rotation. For the study, 115 patients with temporomandibular disorders and 35 dental students without angy signs and symptoms of temporomandibular disorders were randomly selected as the patient group and the contreol group, respectively. Preferred chewing side, Angle' classification, lateral guidance pattern, and affected side were clinically recorded, and the amount of Mandibular body rotational torque movement was measured in wide opening and closure, in right and left excursion with vertical and lateral distance in frontal plane, right and left rotational angel in horizontal and in frontal plane. Masticatory muscle activity of anteriorocclusal contact pattern on maximal hard biting were also observed synchronously with BioEMG and T-Scan , respectively. The observed items were muscle activity of anterior temporalis and superficial masseter, and tooth contact status related to contact number, force, duration, and occlusal unbalance between right and left arch. The data collected were analyzed by SAS statistical program. The results of this study were as follows : 1. Mean value of vertical distance in frontal plane in wide opening and closure was more in control subjects than in patients, but there was no difference for rotational angle. In right excursion, rotational angles were greater in patient group than in control group. 2. Comparison among the subjects by preferred chewing side did not reveal any significant difference, but comparison among patients by affected side showed more rotational amount in bilaterally affected patients than in unilaterally affected patients. 3. Comparison among the subjects by Angle's classification or lateral guidance pattern revealed no difference. There was also no difference between preferred chewing side and contralateral side, and between affected side and contralateral side. 4. Positive correlation in madibular rotational torque movements were observed among vertical distance, total horizontal rotation angle, electromyographic activity of anterior temporalis, tooth contact number, and tooth contact force but total frontal rotation angle almost did not show any correlation with other variables except vertical distance.

• Journal of Oral Medicine and Pain
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• 제26권1호
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• pp.59-73
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• 2001

This study was performed to investigate the effects of occlusal appliance on the mandibular position and the mandibular rotational torque movement during speech. For this study, 20 patients with temporomandibular disorders(TMDs) and 20 normal subjects without any signs and symptoms in the masticatory system were selected as the patient group and as the normal group, respectively. Biopak $system^{(R)}$(Bioresearch Inc., Milwaukee, USA) and a sentence of 'Sue is missing her house' were used for recording and for observing of speech pattern. There were five mandibular positions observed in this study, that is, mandibular rest position, 'ssi', 'her', 'ha', and 's' speech position. In each position, slant and A-P distance in sagittal plane, vertical distance and lateral distance in frontal plane were measured. Amount of the mandibular rotational torque movement were measured at 'her', 'ha' speech position and for all through speech movement. Centric relation splint(CRS) was placed in both groups, but anterior or posterior bite plane were placed in normal subjects only. Data collected were processed and analysed by SPSS windows program. The results of this study were as follows : 1. Mandibular positions in both groups were not different before adaptation, with CRS, and after removal, but total amount of the mandibular rotational torque movement was greater in patients. 2. Mandible was slightly placed anteriorly with CRS at 'her' and 'ha' speech position in patients, but was placed anteriorly at all the five positions in normal subjects. 3. Difference with type of occlusal appliance in normal subjects were noted only for vertical distance at 'ssi' and 'ha' speech position, and the distance with CRS were more than that with posterior bite plane. 4. Mandibular rotational torque movement at 'her' and 'ha' speech position was greater in patients, but the difference was disappeared after appliance removal. And the torque movement was greater at 'ha' speech position than that at 'her' speech position in frontal plane. It could be concluded that the adaptation of occlusal appliance showed a tendency to locate the mandible anteriorly during speech in both groups, but did not affect total mandibular rotational torque movement which was greater in patients.

• Journal of Oral Medicine and Pain
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• 제24권2호
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• pp.207-217
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• 1999

This study was performed to investigate the effects of clutch adaptation on the mandibular rotational torque movement in normal people. 69 dental students were selected for the study. Their mean age were 23.6 years and they did not present any signs and symptoms of temporomandibular disorders. $BioEGN^{(R)}$ with $Rotate^{(R)}$ program was used to observe and record the amount of mandibular rotational torque on protrusion, on right excursion, on left excursion, and on comfortable wide opening movement. The natural tooth contact movement and the movement with clutch were performed in the above four each mandibular movement. Clutch was made by the method used in $Pantronic^{(R)}$ clutch fabrication. Distance of slant frontal which was translatory trajectory in frontal plane and degree of rotational torque in horizontal and in frontal plane were recorded. The data obtained were processed with SPSSWIN program and the results were as follows : 1. Distance of slant frontal in each mandibular movement generally increased with clutch. 2. Degree of rotational torque in horizontal and in frontal plane on protrusion and on lateral excursions did not increase with clutch, but the degree on wide opening increased with clutch. 3. Degree of rotational torque in horizontal plane on protrusion and on lateral excursions did not show any difference between right and left side, but the degree in frontal plane on protrusion and on lateral excursions showed significant difference between right and left side. 4. Total amount of rotational torque from right and left sides on protrusion and lateral excursions were not increased with clutch, but the degree on wide opening movement was increased with clutch. And in this case, degree in horizontal plane was larger than that in frontal plane. 5. Correlation between total amount of rotational torque in horizontal plane and that in frontal plane were highly significant on protrusion and on lateral excursions with or without clutch, but the significant correlation on wide opening without clutch became not significant with clutch.