• The Journal of Korean Academy of Prosthodontics
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• v.51 no.3
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• pp.199-207
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• 2013

Purpose: The importance of occlusal contacts of the natural dentition for durability of teeth, mandibular stabilization, and restorative dentistry is well known. The purpose of this study is to analyze the occlusal contact and guidance pattern of Koreans by evaluating the static occlusion on maximal intercuspal position and measuring dynamic occlusion during straight protrusion. Materials and methods: The occlusal contacts at maximal interincisal position and the occlusal guidance pattern during straight protrusion of 29 subjects were recorded with shimstock foil (Whaledent, Langenau, Germany), T-Scan III (Tekscan Inc., Boston, MA, USA), polyvinylsiloxane registration material (Genie Bite, Sultan Healthcare, Hackensack, NJ, USA) and compared. Occlusal registration procedures were repeated 3 times. The position was fixed to an upright position and the head position was fixed with the Frankfurt horizontal plane paralleling the horizontal plane. Fisher's Exact Test (R-General Public License, ver. 2.14.1) and Pearson's Test were used to assess the significance level of the differences between the experimental groups (${\alpha}=.05$). Results: When using shimstock foil, T-Scan III system, and polyvinylsiloxane registration material, most of the patients showed contact on anterior, premolar, and molar teeth during maximal intercuspal position. Approximately 51% of maximal intercuspal position showed anterior contact using shimstock foil. When examining the protrusive movement using shimstock foil and T-Scan III system, guidance pattern with the central incisor was the most common. Conclusion: During maximal intercuspal position, there were cases in which not all of the teeth showed occlusal contact. During mandibular protrusive movements, one or more maxillary central incisors frequently joined in straight protrusion and the posterior teeth were disoccluded. Therefore, the anterior teeth protect the posterior teeth, and vice versa. Thus, mutually protected occlusion should be applied when reconstructing occlusion.

• Imaging Science in Dentistry
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• v.31 no.4
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• pp.185-192
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• 2001

Purpose: To evaluate the condylar movement at maximal mouth opening on MRI in patients with internal derangement. Materials and Methods: MR images and transcranial views for 102 TMJ s in 51 patients were taken in closed and maximal opening positions, and the amount of condylar movement was analyzed quantitatively and qualitatively. Results: For MR images, the mean condylar movements were 9.4 mm horizontally, 4.6 mm vertically and 10.9 mm totally, while those for transcranial views were 12.5 mm, 4.6 mm, and 13.7 mm respectively. The condyle moved forward beyond the summit of the articular eminence in 41 TMJs (40.2%) for MR images and 56 TMJs (54.9%) for transcranial views. Conclusion: The horizontal and total condylar movements were smaller in MR images than in transcranial views.

• The Journal of the Korean dental association
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• v.25 no.10 s.221
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• pp.913-916
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• 1987

저작운동을 중추신경계와 말초조직의 작용에의해 일생동안 학습과 적응의 가정을 통해 이루어진다. 저작의 양상은 유치가 구강내에 맹출되면서 이루어지며, 상하악 치아의 접촉, 점막과 혀 및 치아상호간에 일어나는 접촉과 치근막의 고유수용기와 악관절 수용기등에 의해 조정되어 최종적으로 에너지소비가 적고 동통이나 불편함이 없이 최대의 효율을 나타내는 양상으로 된다. 그러나 원활한 저작과 하악은동을 이룩하기 위해서는 저작근, 악관절, 상하악 치아의 교합등이 서로 조화를 이루어야 한다. 만일 외상에 의해 악관절의 기능장애가 오면 저작근활동이 변화하고 이에따라 교합장애를 야기한다. 또한 치아를 상실하거나 대합치아간의 조기접촉이 있으면 교합장애가 원인이 되어 근육활동이 변화와 악관절 기능장애를 초래한다. 그리고 때로는 지나친 근육의 활동(이갈이, 지속적 긴장성 수축)에 의해 지나친 치아의 마모로인한 교합장애나 악관절장애를 일으킬 수 있다. 따라서 하악의 기능을 충분히 이해하기 위해서는 교합의 형태학적 관계와 더불어 저작계의 기능적인 면도 고려하여 그 상호관계를 검토하여야 하며 본문에서는 교합에 관련된 저작근의 작용과 이에 영향을 주는 요인 및 교합장애와 근육활동장애의 연관성에 관해 고찰코자 한다.

• The Journal of Korean Academy of Prosthodontics
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• v.27 no.2
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• pp.173-187
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• 1989

The purpose of this study was to evaluate the effects of stabilization occlusal splint by using a simplified condylar path recorder and a dental sound checker. For this study, 11 subjects (10 men and 1 woman) with TMJ disorder were selected from students at Chosun University, School of Dentistry. And they were treated with the stabilization occlusal splint. The condylar movement and the TMJ sound of each subject were recorded and analyzed by using a simplified condylar path recorder and a dental sound checker. The obtained results were as follows: 1. No statistically significant reduction of reduced PRI scores occurred before and immediately after wearing of stabilization occlusal splint. 2. The reduced PRI scores after wearing of stabilization occlusal splint showed statistically significant reduction with the lapse of time. 3. After stabilization occlusal splint therapy, Fisher angle and Bennett angle had almost no change. 4. TMJ sound disappeared in 4 out of 11 subjects.

• The Journal of Korean Academy of Prosthodontics
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• v.33 no.2
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• pp.269-280
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• 1995

저작은 교합과 악운동 뿐만 아리라 근신경계, 고위 중추까지 복합적으로 관여하는 기능적 행위이다. 교합 양상은 다양하게 저작 형태에 영향을 끼치며 저작 효율에도 관여한다. 저작 형태는 다양한 모양을 가지나 두가지 전형적인 군 즉, 전방에서 관찰시 그 양상이 수직적이며 chopping운동을 닮은 군과 저작 형태가 주로 측방으로 이루어지며 grinding을 하는 군으로 나눌 수 있다. 본 연구의 목적은 저작 형태의 치아가 교합접촉 및 저작 효율에 미치는 영향을 고찰해 보고자 하는 것이다. 하악운동궤적기록기를 이용하여 정상교합을 가진 치과대학생중 전형적인 2가지 저작형태를 보이는 각 10명씩을 피검자로 선택하였다. 3가지 하악위 즉, 중심위, 작업측 비작업측에서의 교합접촉을 고무형 교합인기재로 기록하여 천공부의 직경이 1mm이하면 1점, 1-2mm또는 직선상이면 2점, 2mm이상이면 3점으로 평가하여 각 점수의 합으로 좌우 소구치 및 대구치의 접촉 지수를 측정하였다. 저작 효율을 평가하기 위해 땅콩 3g(${\pm}0.01g$)을 20회 저작하게 한 후 3회 입을 헹구어 뱉게 하였다. 체눈 크기가 각 0.425, 0.60, 0.85, 2.0, 4.0인 체에 거른 후 $65^{\circ}C$로 오븐에서 세시간 말려 무게를 측정하고 중심 크기$(M_{50})$과 저작효율치(R)를 계산 비교하여 다음과 같은 결론을 얻었다. 1. Chopping형은 grinding형에 비해 중심위에서 더 넓은 교합접촉을 보였다(P<0.01). 2. Grinding형은 chopping형에 비해 측방위에서 더 넓은 교합접촉을 보였다(P<0.01). 3. Chopping형은 중심크기($(M_{50})$)과 저작효율치(R)로 비교하였을 때 더 좋은 저작 효율을 보였다(P<0.01).

• The Journal of Korean Academy of Prosthodontics
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• v.55 no.4
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• pp.419-426
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• 2017

In implant restorations, it is difficult for the patient to percept any symptoms. In addition, they are absent of shock absorbers, which can lead to mechanical failure if stress distribution is not considered. Since maxillary anterior multiple-implant restorations play a significant role in guiding the functional movement of the mandible by distributing lateral force, it is crucial to form appropriate occlusion. The use of the T-scan system is more advantageous in assessing 'dynamic occlusion', such as the change of occlusion over time, the amount of tooth contact during functional movement, and assessing the occlusion in the less-visible posterior teeth. The case is reported as it has satisfactory results in harmonious anterior guidance of a maxillary anterior multiple-implant restoration using T-scan analysis.

• Journal of Oral Medicine and Pain
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• v.37 no.2
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• pp.107-112
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• 2012

Orofacial movement disorders (OMD) are uncontrolled movement of the muscles involving the face, tongue, lip and mandible. Due to variable oral and lingual muscles affected, the patients with OMD are interfered with the appropriate performance such as chewing, swallowing and talking. In this study, there are 4 OMD cases with oral dryness that saliva flow rate is decreased or not. The symptoms are improved after oral administration of pilocarpine to 4 patients with OMD. Therefore, we suggest that objective or subjective oral dryness could be etiologic factor in OMD and pilocarpine could be regarded as medication for OMD.

• Journal of Oral Medicine and Pain
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• v.33 no.4
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• pp.339-352
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• 2008

Aims: The aims of this study were to identify the association between cervical muscle pain and TMD by pressure pain response, and to find cervical muscles showing moderate to severe pressure pain that are correlated with masticatory muscle pain. Methods: Patients(n=129, female 65.9%, mean age 28.8 years) answered a TMD questionnaire asking about headache, neck pain, emotional stress, sleep disturbance, parafunction habits, and pain intensity. A clinical examination of the masticatory system was performed. Of the neck muscles, (1) the upper sternocleidomastoid, (2) the middle sternocleidomastoid, (3) the upper trapezius, (4) the splenius capitis, (5) the semispinalis capitis, (6) the scalene medius, and (7) the levator scapulae muscles were examined by palpation. Pressure pain or tenderness of all palpation sites was scored from 0 to 3 according to the pain response. The variables of sum of pressure pain scores were calculated from pressure pain scores and were used for statistical analyses. Results: Eighty patients(62.0%) answered that they suffer from neck pain in the TMD questionnaire. More than 40% of sternocleidomastoid and upper trapezius examination sites showed moderate to severe tenderness in the cervical muscles, and 36% of middle masseter in the masticatory muscles. For the 129 patients, the sum of cervical muscle pain scores(mean=12.88, SD=8.06) and the sum of TMD pain scores(mean=5.36, SD=5.10) were moderately correlated($\rho$ = 0.502, P < 0.001). The sum of TMD pain scores tends to increase as the sum of cervical muscle pain scores increases(Y = 0.395${\cdot}$X, $R^2$ = 0.659, P < 0.001). In the patients with masticatory muscle disorders, the sum of sternocleidomastoid and upper trapezius pain scores(mean = 8.67, SD = 4.95) and the sum of temporalis and masseter pain scores(mean = 3.37, SD = 3.56) showed moderate correlation($\rho$ = 0.375, P < 0.001). Those two variables were in a proportionate relationship(Y = 0.359${\cdot}$X, $R^2$ = 0.538, P < 0.001). In a partial correlation analysis of the sum of unilateral pain scores, the sum of right cervical muscle pain scores and the sum of left cervical muscle pain scores showed the highest correlation(r = 0.802, P < 0.001). The sum of right TMD pain scores and the sum of left TMD pain scores were moderately correlated(r = 0.481, P < 0.001). For the twenty patients with unilateral TMD pain, the partial correlation coefficient between the sum of ipsilateral cervical muscle pain scores and the sum of contralateral cervical muscle pain scores was the largest(r = 0.597, P = 0.009). A partial correlation between the sum of primary TMD side pain scores and the sum of ipsilateral cervical muscle pain scores was 0.564(P = 0.015). Conclusions: TMD is associated with cervical muscle pain on condition of pressure pain response to palpation. Of the cervical muscles, sternocleidomastoid and upper trapezius frequently exhibit moderate to severe pressure pain, and they are closely related to the masticatory muscle pain. The characteristic of symmetric involvement of pain is prominent in cervical muscles; however, TMD can affect the level of cervical muscle pain to modify its symmetric nature.

• The Journal of Korean Academy of Prosthodontics
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• v.36 no.4
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• pp.533-548
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• 1998

The purpose of this study was to investigate the influence of balancing interference on the mandibular movement and masticatory muscle activity. 5 subjects(male. average age of 24.3) without dysfuction in masticatory system were selected. The balancing interference was provided by construction of cast metal crown and onlay on the upper and lower first molars. Clinical examination, changes displacement and velocity, and muscle activity were recorded and analyzed by means of BioPak system(Bioresearch Inc., Milwaukee Wisconsin. USA). The results were as follows ; 1. In clinical examination, various symptoms were reported by all subjects after application of interference. Almost symptoms were subsided after elimination of interference. 2. In the border movements in frontal plane, lateral border movement toward non-interference side was changed according to the interference after application of interference. Immediately after removal of interference, border movements' pattern was recovered as same as before experiment. 3. During gum chewing on the non-interference side, horizontal movement was decreased immediately after application of interference(p<0.05). 1 week after application of interference, horizontal movement was more decreased in 3 subjects and showed a chopping type masticatory stroke. But in 2subjects, horizontal movement was increased to avoid interference. 4. In EMG of the mandibular rest position, no significant changes were showed in the experiment period(p>0.05). 5. During gum chewing on the interference side, the activity of opposite temporal muscle was increased immediately after application of interference(p<0.05). 1 week after application of interference. The activity of ipsilateral temporal muscle and left and right masseter muscles was increased (p<0.05). 1 week after elimination of interference, increased muscle activity was recovered about the same level as before experiment. 6. During gum chewing on the non-interference side, 1 week after application of interference, the activity of ipsilateral temporal muscle was increased (p<0.05). 1 week after elimination of interference. increased muscle activity was returned about the same level as before experiment.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.3
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• pp.43-53
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• 1991

It is important to harmonize the occlusion with TMJ and neuromuscular system. However, clinically, how to harmonize is very difficult. The mandibular movement is the motion in which all component part of stomatognathic system participate. This study was performed to compare mandibular movement of mandibular prognathic patients group with that of normal group, to ascertain which components of mandibular movement have differences between two groups, and to use for occlusal treatment of mandibular movement. Thirteen adult who have physiologically normal occlusion and are free of TMJ dysfunction were selected as a control group(Group 1). Eight adult who are mandibular prognathic patient and have more than four anterior teeth crossbite, therefore have not anterior guidance function and have posterior interference at protrusion were selected as a experimental group(Group 2). Electronic pantograph, Denar Pantronic (Denar Corp., U.SA.), was used to record mandibular movement. Pantronic survey was performed by using an arbitrary hinge axis according to manufacturer's direction. Of the Pantronic recordings, immediate side shift (ISS), progressive side shift (PSS), orbiting condylar path (ORB), protrusive condylar path (PRO) between two groups were compared and analysed. The results were as follows: 1. The average protrusive and orbiting condylar inclination of mandibular prognathic patient$(28.44^{\circ},\;36.94^{\circ})$ was significantly lower than those of normal group$(40.15^{\circ},\;48.00^{\circ})$ (P<0.01). 2. There was no statistically significant difference between .the average immediate and progressive side shift of mandibular prognathic patient $(0.37mm,\;6.19^{\circ})$ and those of normal group$(0.52mm.\;5.96^{\circ})$ (P>0.01). 3. The significant correlation was found between orbiting condylar inclination and protrusive condylar inclination.