• 대한치과교정학회지
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• 제26권6호
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• pp.691-703
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• 1996

Three-dimensional finite element model was made from adult skull to find desirable direction of retraction force to treat skeletal class II malocclusion. The retraction force of 400g was applied to the first molar. The direction of the force application was $23^{\circ}$ downward, parallel, $23^{\circ}$ upward and $45^{\circ}$ upward to the occlusal plane. The stress distribution and the displacement within the maxilla were analyzed by three-dimensional finite element method. The findings obtained were as follows: 1. Maxillary first molar was displaced posteriorly and inferiorly in $23^{\circ}$ downward, parallel, $23^{\circ}$ upward retraction but it was displaced posteriorly and superiorly in $45^{\circ}$ upward retraction. 2. ANS, A point and prosthion were moved posteriorly and inferiorly and pterygomaxillary fissure was moved posteriorly and superiorly. Clockwise rotation of maxilla occurred when retraction force was applied. 3. The degree of clockwise rotation of maxilla was greatest when the force was applied $23^{\circ}$ upward to the occlusal plane and was least when the force was applied $23^{\circ}$ downward to the occlusal plane. 4. Large tensile stress appeared in maxillary first molar and alveolar bone and the infraorbital region of maxilla when the force was applied $23^{\circ}$ downward to the occlusal plane. Tensile stress was smaller as the direction of force move upward. 5. Large compressive stress was appeared in maxillary first molar and infraorbital region in $45^{\circ}$ upward case and large compressive stress occurred in the posterior part of maxilla as the retraction force was upward.

• Journal of Oral Medicine and Pain
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• 제15권1호
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• pp.117-124
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• 1991

The purpose of his study was to investigate the variations of occlusal contact pattern according to chewing side preference. The author selected 59 dental students (mean age 23.6 years) who had no signs and symptoms of masticatory disorders and divided into two groups, that is, bilateral chewing side group and unilateral chewing side group, respectively. For recording, T-Scan System(Teksan Inc., USA) was used and the recorded occlusal contacts were examined as to the number of occlusal contacts, points distribution in dental arch, time sequence and force snapshot. The obtained results were as follow s: 1. Total number of occlusal contacts were more in unilateral chewing side group and there were significant difference in number between right and left side or between chewing and less-chewing side in all two groups. 2. All items related to time sequence showed no statistical significant difference between two groups in any case. 3. Unilateral chewing side group had more occlusal contact force than bilateral group, especially in chewing side. From the above finding, the author considered that there was occlusal unbalance in unilateral chewing side group. 4. Chewing side preference would possibly have more effects on the occurrence rate of anterior tooth contact that the rate of prolonged their contact but proved.

• 비파괴검사학회지
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• 제29권3호
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• pp.214-218
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• 2009

The occlusal force of the tooth leads to loss of tooth tissue owing to attrition and abrasion, and may cause abfraction and pathological change of the dentin. Thus, we developed finite element models, examined them by applying ordinary occlusal force, and analyzed the stress distribution. Specimens used were mandibular first premolars from 15 Korean males and 13 females and were made into finite element models from medical images that were obtained using a Micro-CT. We have found that the irregular feature of the tooth is not only useful to masticating and pronouncing as well known, but it is also suitable for protecting inner tissue by dispersing stress and delivering proper pressure to periodontal tissue to continue a physiological action. Also, image analysis could let us know the factor that is the cause of a disorder due to stress concentration in the cervical line. These results are expected to support the field of dental treatment planning, operating procedure and clinical trial, and the advance of technical expertise to develop implants and dentures.

• 대한치과교정학회지
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• 제40권5호
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• pp.304-313
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• 2010

본 연구는 한국인 정상교합자와 부정교합자 사이의 교합력의 크기와 교합 시의 접촉 면적의 차이 및 골격 형태와 교합 관계, 연령, 성별이 교합력의 크기에 영향을 미치는지 알아보기 위해 시행되었다. 정상교합자 15명, 부정교합자 636명에서 일회용 pressure sensitive sheet (Dental $Prescale^{(R)}$ 50H, typeR, Fuji Film Corp., Tokyo, Japan)를 자연 두부위에서 최대 근력으로 교합하도록 한 후, CCD camera ($Occluzer^{(R)}$ FPD 707, Fuji Film Corp., Tokyo, Japan)로 판독하여 교합력의 크기 및 접촉 면적을 측정하였다. 정상교합자군의 교합력의 크기는 $744.5{\pm}262.6N$, 접촉면적은 $24.2{\pm}8.2mm^2$으로, 부정교합자군의 $439.0{\pm}229.9N$, $12.4{\pm}10.7mm^2$에 비해 교합력의 크기와 접촉 면적이 유의하게 컸다 ($p$ < 0.05). 부정교합자군의 경우 연령에 따른 교합력의 차이는 없었으나, 남자가 여자에 비해 큰 교합력을 가지고 있었다 ($p$ < 0.05). 악안면의 전후방적인 골격 형태를 나타내는 ANB 및 골격성 1급 부정교합에서의 구치부의 Angle 분류는 교합력에 유의한 차이를 나타내지 않았으나, 수직적인 골격 형태를 구분하는 mandibular plane angle, gonial angle이 큰 경우, 교합력이 유의하게 작았다 ($p$ < 0.05). 하지만, 교합력의 크기와 접촉 면적간에는 높은 상관관계가 존재하는 점과 접촉 면적을 통제한 상태에서의 골격 형태와 교합력의 크기 사이에는 유의할 만한 상관관계가 없는 점을 고려한다면 수직적인 골격 형태가 직접적으로 교합력에 영향을 주기보다는 수직적인 골격 형태에 따른 접촉 면적의 감소가 교합력 저하에 관여한다고 판단된다.

• Journal of Oral Medicine and Pain
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• 제17권2호
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• pp.27-35
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• 1992

The purpose of this study was to evaluate the size of the temporomandibular joint space by the increase of the occlusal force on the working side and the non-working side during unilateral biting. For the study, 22 normal adults, age from 23 to 25, who had normal or class I molar relationship and had no symptoms on TMJ area and masticatory muscles were selected. Transcranial TMJ radiograph was taken during unilateral biting with the sensor of occlusal load measuring device (MPM-3000 ; Nihon Kohden Kogyo Co. Ltd., Japan) on 1st molar teeth of right and left side given to force of 0kg, 10kg, 20kg and 30kg respectively with Accurad-200(Denar Corperation's product). The radiographs were traced on the screen, with enlaged as 5 times. The size of temporomandibular joint space at anterior, superior and posterior compartment were measured with Dumas's method (reference line between squamotympanic fissure and the lowest point of articular eminence). The following results were obtained by this study. 1. The size of anterior TMJ space showed a tendency to decrease on the working side and increase on the non-working side by the increase of the occlusal force, but had no statistical significancy (P>0.05). 2. The size of superior TMJ space showed a tendency to increase on the working side and decrease on the non-working side by the increase of the occlusal force (P<0.05). 3. The size of posterior TMJ space showed a tendency to decrease on both working and nonworking side, but had no statistical significancy (P>0.05)

• Journal of Oral Medicine and Pain
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• 제18권2호
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• pp.71-79
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• 1993

Many types of occlusal splints are used for treatment of craniomandibular disorders. Most widely used splint among them is flat-type centric relation splint. Insertion of splint into the mouth may cause increasing of vertical dimension, masticatory muscle realignment and rearrangement of maxillo-mandibular relationship, so as a result of splint treatment, occlusal relation may vary whether you like it or not. From this point of view, occlusal state of patient shold be frequently monitored to prevent undesired or harmful effect during occlusal splint therapy. The purpose of this study was to investigate the effect of occlusal splint, especially centric relation splint, on the occlusal contact state after 3 months treatment. 32 patients with craniomandibular disorders who had unilateral symptoms participated in this study. To observe and record occlusal contact state, the author used T-Scan system (Tekscan Co. U.S.A.) at both pretreatment and posttreatment. The recorded date were analyzed with regard to contact number, contact force and contact time, change of anterior tooth contact and coincidence of first contact point with affected side were observed, too. Aan last, the subjects were divided into 2 groups and compared, according to average value of VAS index, with respect to joint pain, sound and limitation of movement, respectively. The collected date were statistically processed with SPSS and the result as follows : 1. Total occlusal contact number and force were not changed by occlusal splint therapy but total occlusal contact time decreased slightly. 2. There was a tendency of increasing number of subjects with anterior tooth contact after treatment and change of first contact point side were observed in as many as 40.6% of subjects. 3. There were no difference between higher and lower group of VAS index, and between pretreatment and posttreatment in each group, either.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제34권5호
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• pp.537-542
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• 2008

BSSRO is most frequently operated among orthognathic surgery techniques for repairment of maxillofacial deformities. In case of patients with maxillofacial asymmetry accompanying mandibular protrusion who are operated by BSSRO, this study considers the recovering time for masticatory force of each tooth and Masseteric EMG and the adequate time enabling normal occlusion. The patients who are operated with BSSRO under general anesthesia in Dankook Dental Hospital, Department of OMS are selected for this study. The control group is devided into 2. 26 patients with facial asymmetry accompanying mandibular protrusion are selected for group 1 and their maximum voluntary bite force and masseteric EMG are measured. Group 2 is formed by volunteers with healthy dentition who are measured maximum bite force and masseteric EMG on both sides of the mouth. At the week of 3rd, 5th, 7th, 9th and 11th, Mann-Whitney U test is carried on for statistical analysis and the result is as follows. 1. Patients with mandibular protrusion showed apparently low maximum bite force and masseteric EMG than patients with normal occlusion. 2. In comparison with control group 1, Occlusal force is regained in incisors and canines at the 9th week and in premolars and molars, 11th week and masseteric EMG is regained at 11th week. 3. Comparing to normal occlusal patients, no recovery could be found in experimental group in every parts of the mouth.

• Journal of Oral Medicine and Pain
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• 제31권3호
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• pp.265-274
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• 2006

측두하악관절 내장증, 그 중에서도 정복성 관절원판 변위(Disc displacement with reduction; DDwR)는 가장 흔하게 발생하는 측두하악관절 질환으로, 저작 능력에 다양한 영향을 미칠 것으로 생각되어져 왔다. 저작 능력을 평가하는 객관적이고 가시적인 수단으로 최대 교합력의 측정이 널리 통용되어져 왔는데, 과거 많은 연구자들이 측두하악장애(TMD)와 교합력의 관계에 대한 연구를 시도하였으나, 피험자의 개인적 특성이나 측정 방법의 차이 등으로 인하여 통일성 있는 결과를 얻지 못하고 있으며, 측두하악장애로 인한 통증이 교합력 및 저작능력을 감소시킨다고 보고된 바 있으나 측두하악관절의 구조적 변화와 저작능력의 관계에 대한 연구는 아직 충분히 이루어져 있지 않다. 본 연구에서는 측두하악관절의 구조적 변화와 저작 능력의 관계를 파악해 보고자 개구시 무통성의 관절음을 보이는 환자 39명 및 대조군 59명을 대상으로 최대 교합력, 교합 접촉 면적 및 교합압을 감압필름법(pressure sensitivie film)을 이용하여 분석, 평가한 후 다음과 같은 결과를 얻었다. 1. 정복성 관절원판 변위 환자군이 대조군보다 높은 최대 교합력(P < 0.01) 및 넓은 교합 접촉 면적(P < 0.05)을 나타내었다. 2. 단위 면적당 평균 교합압은 대조군과 정복성 관절원판 변위 환자군 간에 있어서 유의성있는 차이를 보이지 않았다(P > 0.05). 3. 남녀간의 차이에 있어서, 정복성 관절원판 환자군과 대조군 모두에서 남성이 여성보다 높은 교합압을 나타내었으나(P < 0.05), 평균 교합압과 교합 접촉 면적은 유의성있는 차이를 보이지 않았다(P > 0.05). 이상의 결과로부터 얻을 수 있는 결론은 측두하악관절의 정복성 관절원판 변위가 교합 기능을 변화시키는 한 요소로서 작용할 수 있다는 점이다. 향후의 연구에 있어서 근전도 등을 이용한 저작근 활성도 측정을 병행함이 유용할 것으로 사료되며, 교합력에 영향을 미치는 다른 요소가 통제된 보다 대규모 환자집단에 대한 연구가 필요할 것으로 사료된다.

• 대한의생명과학회지
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• 제30권1호
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• pp.17-23
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• 2024

In this study, the changes in occlusal strength and oral environment before and after the use of natural gargles containing cinnamon were confirmed. This study involved 42 adults aged 19 or older living in Busan from November 25 to December 2, 2023. Twenty-one people were randomly selected for each of the regular and natural gargles. In this study, the group using natural gargles confirmed an increase in saliva buffering power, a decrease in O'Leary index, and an increase in occlusal strength. Through this, it was confirmed that natural gargles containing cinnamon are helpful in improving the oral environment and occlusal strength.

• 구강회복응용과학지
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• 제34권3호
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• pp.147-156
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• 2018

교합점 기록재를 통해 교합점을 분석하는 방법이 신뢰할 만한가에 대해서는 사용하는 방법이 결과에 미칠 수 있는 영향을 고려해야 한다. 교합점 기록은 교합점 기록재료와 두께, 교합력, 사용 횟수, 재료의 물리적 특성, 매개 물질 등 많은 변수에 의해서 정확도, 신뢰도에 영향을 받을 수 있다. 그럼에도 불구하고 교합점 기록재에 대한 연구는 환자의 교합력과 기록재의 두께 등 일부 요소에 대한 평가가 주를 이루어 다양성이 부족하다. 변수를 통제하기 위해 교합지는 가능하면 매 회 새것을 사용하고 구강 내 건조상태를 확보하며 가급적 얇은 교합지를 사용하여야 한다. 또한, 한가지 방법만으로 분석하는 것은 지양하여야 하며, 보조 수단을 함께 활용할 것이 추천된다.