• Journal of Periodontal and Implant Science
• /
• v.47 no.4
• /
• pp.211-218
• /
• 2017

Purpose: The purpose of the present study was to perform a pattern analysis in patients with temporomandibular disorder (TMD) resulting from unilateral mastication due to chronic periodontitis. Methods: Thirty participants with signs or symptoms of TMD who engaged in unilateral mastication due to periodontitis-related discomfort (test group) were selected. Another 30 subjects exhibiting signs or symptoms of TMD resulting from unilateral mastication not due to chronic periodontitis (control group) were also recruited. An interview-based questionnaire was administered, and an examination of the temporomandibular joint (TMJ) with determination of periodontal status was performed. Results: The duration of unilateral mastication was significantly longer in the control group than in the test group. There was a significant negative correlation between the duration of unilateral mastication and the Community Periodontal Index score. Using the Research Diagnostic Criteria for TMD (RDC/TMD) axis I algorithms, all the subjects were assigned to 3 main groups. The test group exhibited significantly a higher diagnostic distribution of group III (arthralgia, osteoarthritis, or osteoarthrosis), and in both the test and control groups, the number of diagnoses was larger for the non-chewing side. The control group showed a significantly higher diagnostic distribution of group I (myofacial pain), and in both the test and control groups, the number of diagnoses was larger for the chewing side. Conclusions: The results of the present study indicate that unilateral mastication due to chronic periodontitis could induce not only pain but also structural TMJ changes if adequate treatment is not administered and supported within a short time from the onset of the condition. Therefore, immediate treatment of chronic periodontitis is recommended to prevent not only the primary progress of periodontal disease, but also secondary TMJ-related problems. Furthermore, subjects who have suffered chronic long-term periodontitis without treatment should be urged to undergo a TMJ examination.

• The korean journal of orthodontics
• /
• v.22 no.2 s.37
• /
• pp.389-412
• /
• 1992

Along with form and function relationship of craniofacial growth comes a concern for the masticatory muscles with postnormal occlusion. It is the aim of this study to grope the certain differences upon the electromyographic activities of the masticatory muscles between normal occlusion and class II malocclusion during the varieties of oral functions. 26 persons of normal occlusion whose mean age were 18.9-25.6 years and another 26 persons of class II malocclusion whose mean age were 19.0-28.9 years served for this study. The electromyographic recordings processed by $Medelec^{\circledR}$ MS 25 EMG apparatus were taken from the anterior and posterior temporal, and anterior and posterior masseter muscles of both sides, and suprahyoid muscles as well. Analyses of the data toward such specific activities as mandibular rest, maximal biting, chewing gums and swallowing peanuts turned out the following summary and conclusions. 1. The maximal mean amplitude of the posterior temporalis showed significant augmentation in class II malocclusion, however the anterior temporalis, posterior masseter, and suprahyoid muscles manifested meaningful diminutions. 2. Stronger posterior temporalis and weaker anterior masseter and suprahyoid muscles were arranged in maximal biting with parameters of maximal mean amplitude. 3. The anterior temporalis of working side expressed smaller maximal mean amplitude in class II malocclusion. Significant swelling in duration were shown at anterior and posterior temporalis of working side, and posterior temporalis of balancing side in class II malocclusion, and marked reduction at anterior masseter of balancing side and posterior masseter of working side as well. The lessened latency were expressed at anterior masseter of working side, and anterior and posterior masseter of balancing side. Class II malocclusion group had significant prolongation of silent period duration. Mean silent period duration of 10.75 msec in normal occlusion and 24.37 msec in class II malocclusion were calculated. 4. Significant augmentations of maximal mean amplitude while swallowing peanuts were yielded at right anterior temporalis and posterior temporalis of both sides, however left anterior masseter and right posterior masseter showed diminution. No significant differences in duration showed at every muscle examined in class II malocclusion group.5. Weaker masseter and stronger temporalis were suggested as characteristics of class II malocclusion.

• The korean journal of orthodontics
• /
• v.27 no.4 s.63
• /
• pp.549-557
• /
• 1997

This study was designed to investigate the attrition pattern in Angle Class III malocclusion with facial asymmetry. The sample consisted of three groups, the 20 subjects of normal occlusion group(Group I), the 12 subjects of class III malocclusion without facial asymmetry group(Group II) and 17 subjects of Class III malocclusion with facial asymmetry group(Group III). Attrition areas from canine to second molar on both sides in upper and lower arch, totally twenty, was marked by pencil and mesured by computer system(INTERGRAPH CO. USA) 2 times and the average value was used for date processing. Attrition areas from canine to second molar on both sides in upper and lower arch, totally twenty, was marked by pencil and mesured by computer system(INTERGRAPH CO. USA) 2 times and the average value was used for date Processing. All attrition areas were measured 2 times and the average value was used for data processing The data were statistically analyzed by SAS program. The results of this study were as follows. 1. Total attrition area in Group I was larger than in Group II and III. 2. There was no significant difference in attrition area between right and left side in each group, but attrition area in Group III was larger than in Group I and II. 3. In Group I, Maxillary attrition area was larger than mandibular attrition area, but in Group ll and III, there was no significant difference in attrition area between maxilla and mandible. 4. In Group III, the attrition area of deviated side was target than undeviated side 5. There was no significant difference in attrition area between chewing side and non-chewing side in each group. 6. The total attrition area was unaffected by gender.

• The Korean Journal of Physiology
• /
• v.3 no.1
• /
• pp.33-44
• /
• 1969

Electoromyographic studies were performed on the action of the muscles of the temporomandibular joints following exfoliation of the deciduous teeth. The subjects examined, being 50 children. between the age of 6 and 13 years, divided into 5 groups. They were; 1) Deciduous dentition were complete in the first group. 2) Deciduous incisors were missing in either upper or lower jaw in the second group. 3) Deciduous canine and molars were missing in the left side of either upper or lower jaw in the third group. 4) Deciduous canine and molars were missing in the right side of either upper or lower jaw in the fourth group. 5) Permanent dentition completed in the fifth group(except third molars). Electromyogram was recorded with 4 channel polygraph (Grass model VII modified for 7P3). Electrodes which were the cup-typed gold discs, 9 millimeters in the diameter, were located on the anterior, middle and posterior lobes of the temporal muscles, and also on the superficial and deep layers of the masseter muscles. Paired electrodes were held by electrode cream so that they were pressed on the skin surface at right angle, adhesive tape being used to anchor them. The distance of the pair electrodes was about 5 millimeters. The results obtained were as follow: 1) In rest position of mandible; All groups showed slight, electrical activities in the muscles involved, but in the middle lobe of temporal muscle they were slightly higher. 2) In molar occlusion of mandible; High activity-anterior lobe of temporal muscle and superficial layer of masseter muscle. Moderate activity-deep layer of masseter muscle. Low activity-middle and posterior lobes of masseter muscle. There were no differences among the first, the second and the fifth groups. In the third group the muscle activity was weaker than that of the right, and in the fourth group opposite characteristics was revealed. 3) In incisal bite of mandreble; Hight activity-superficial layer of masseter muscle. Modertae activity-deep layer of masseter muscle. Low activity-anterior, middle and posterior lobes of temporal muscle. The first, the third, the fourth and the fifth groups showed no differences but the second group showed less activity than those of others. 4) In protrusion of mandible; High activity-deep layer of masseter muscle Moderate activity-superficial layer of masseter muscle. Low activity-anterior, middle and posterior lobes of temporal muscle. In the first, the fourth and the fifth groups, there were no differences in the activities, but the second group showed less activity than the others. 5) In retrusion of mandible; High activity-deep layer of masseter muscle. Moderate activity-superficial layer of masseter muscle. Low activity-anterior, middle and posterior lobes of temporal muscle. In the first, the third, the fourth and the fifth groups, there were no differences but the second group showed less activity than the others. 6) In lateral excursion of the mandible (either direction); High activity-posterior lobe of temporal muscle. Moderate activity-anterior and middle lobes of temporal muscle. Low activity-superficial and deep layers of masseter muscle. The muscle action potentials were weaker than those of the right side in the third group and vice ver'sa in the fourth group. 7) In chewing movement; Temporal muscle activities were higher than those of masseter, especially in the middle lobe of temporal muscle the activity was highest. Right side muscle activities were higher than those of the left in the third group and, on the contrary, the left side was dominant over the right in the fourth group.

• Journal of Oral Medicine and Pain
• /
• v.38 no.3
• /
• pp.275-289
• /
• 2013

This study was conducted to investigate and analyze the dental patients' awareness and understanding about TMDs. Among the total number of 243 patients who had visited the department of dentistry of Busan Paik Hospital, Inje University or Hanvit dental hospital in Ulsan metropolitan city and participated in the survey, 195 patients who filled in all parts of the questionnaire were selected as the subjects. The results were as follows. 1. The subjects who were aware of the term, "TMDs" were 17.4%. The group with total education period of 12 years and over was significantly more aware of "TMD"(82.4%, p<0.01) than the other group. The subjects who were aware of the term, "jaw joint disease" were 81.0%. 30 to 49 age group(45.6%, p<0.05) and the group with total education period of 12 years and over(60.1%, p<0.01) were significantly more aware of "jaw joint disease" than other groups. 2. More than half of the subjects chose "overuse of the jaws" as the concept of jaw joint disease(50.6%). 3. TV, radio(41.4%) was the most frequent source of awareness about jaw joint disease followed by family and friends(20.2%), hospitals and health professionals(18.2%), internet(15.7%) and newspapers, magazines(4.5%). Among the respondents who were aware of jaw joint disease through TV, radio, 30 to 49 age group showed significantly higher percentage(52.4%, p<0.05) than other age groups. Among the respondents who were aware of jaw joint disease through internet, 18 to 29 age group showed significantly higher percentage(61.3%, p<0.01) than other age groups. Among the respondents who were aware of jaw joint disease from hospitals and health professionals, the group with total education period of 12 years and over showed significantly higher percentage(75.0%, p<0.05) than the other group. 4. Noise during mouth opening and closing(26.9%), mouth opening difficulty(25.1%) and jaw pain(13.7%) were the most frequently responded sign and symptoms of jaw joint disease. For the causes of jaw joint disease, enjoying hard food chewing(19.5%), occlusal discrepancy(19.0%) and chewing with one side only(18.5%) were responded in sequence. TMJ surgery(28%) was the most frequently responded treatment method for jaw joint disease, followed by occlusal appliance therapy(23.9%) and physical therapy(14.6%). For preventive method of jaw joint disease, avoid eating hard food(21.1%), avoid opening mouth wide(17.0%) and simultaneous using of molar of both side when chewing food(15.4%) were chosen frequently.

• Journal of Korean Physical Therapy Science
• /
• v.7 no.1
• /
• pp.295-310
• /
• 2000

The relationship between symptoms of temoromandibular joint dysfunction(TMJD) and stomatognathic habit was studied in 500 adolescents(mean age 22.45). The severity of TMJD was determined by using a self-reported anamnestic questionnaire composed of 10 questions regarding common TMJD. The index of oromandibular habit was determined by using a self-reported anamnestic questionnaire composed of 17 questions. There was a positive correlation(p<0.01) between the index of TMJD and index of stomatognathic habit. The most frequent symptoms were clicking sounds from the TMJ(37.4%) and a feeling of pain in the jaws(33.3%). The most frequent stomatognathic habit were a chin support(69.8%) and one side chewing(68.0%).

• Journal of Korean Neurosurgical Society
• /
• v.49 no.5
• /
• pp.284-286
• /
• 2011

Glossopharyngeal neuralgia is a relatively rare condition characterized by severe, paroxysmal episodes of lancinating pain in the tongue, throat, ear, and tonsil. This disorder is assumed to be due to compression of the glossopharyngeal nerve by vascular structures. A 47-year-old woman complaining of sharp and lancinating pain in the right periauricular and submandibular areas visited our hospital. Swallowing, chewing, and lying on her right side triggered the pain. Her neurologic examination revealed no specific abnormalities. The results of routine hematologic and blood chemistry studies were all within normal limits. Carbamazepine and gabapentin were given, but her symptoms persisted. Her pain was temporarily relieved only by narcotic pain medication. MRI showed an arachnoid cyst located in the right cerebellomedullary cistern extending to the cerebellopontine cistern. Cyst removal was performed via a right retrosigmoid approach. Lateral suboccipital craniotomy was performed using the right park-bench position. After opening the dura and cerebellopontine angle, the arachnoid cyst was exposed. The arachnoid cyst was compressing the flattened lower cranial nerves at the right jugular fossa. Her symptoms resolved postoperatively. Two months after the operation, she was completely free from her previous symptoms.

• Journal of Technologic Dentistry
• /
• v.38 no.3
• /
• pp.151-156
• /
• 2016

Purpose: The dental implant should be enough to endure chewing load and it's required to have efficient design and use of implant to disperse the stress into bones properly. This study was to evaluate the stress distribution on a supporting bone by lengths and diameters of the implant fixture. Methods: The modeling and analysis of stress distribution was used for the simple molar porcelain crown model by Solidworks as FEM program. It was designed on applying with tightening torque of 20 Ncm of a abutment screw between a cement retained crown abutment and a fixture. The fixtures of experimental model used 10, 13mm by length and 4, 5mm by diameter. A external vertical loading on the two buccal cusps of crown and performed finite element analysis by 100 N. Results: The maximum von Mises stress(VMS) of all supporting bone models by fixture length and diameter were concentrated on the upper side of supporting compact bone. The maximum stress of each model under vertical load were 164.9 MPa of M410 model, and 141.2 MPa of M413 model, 54.3 MPa of M510 model, 53.6 MPa of M513 model. Conclusion: The stress reduction was increase of fixture's diameter than it's length. So it's effective to use the wider fixture as possible to the conditions of supporting bone.

• Archives of Craniofacial Surgery
• /
• v.22 no.1
• /
• pp.45-51
• /
• 2021

Background: Mandibular deficiency leading to facial asymmetry causes cosmetic deformity as well as psychological stigma for the patient. Correction of these mandibular asymmetries is a major challenge. The study investigates the efficacy of bidirectional mandible distraction for the treatment of mandibular deficiency. Methods: This prospective study included six individuals aged between 17 and 24.4 years. Five patients had hemifacial microsomia and one had unilateral temporomandibular joint ankyloses. All patients underwent mandibular distraction osteogenesis. Postoperative skeletal changes in affected mandible, and changes in occlusal plane and oral commissure cant were evaluated using three-dimensional reconstruction. Patient satisfaction and understanding of the procedure were assessed through three questionnaires administered during pre-distraction, distraction and post-distraction phases. Results: In pre-distraction phase, aesthetic appearance seemed to be the primary indication for surgery. In distraction phase, pain while chewing was the primary handicap. In post-distraction phase all patients were satisfied with the aesthetic outcome. The facial deformity was improved through mandibular distraction osteogenesis. On the affected side in all the patients, height and length of the mandible increased. Canting of the occlusal plane and oral commissure was corrected. Conclusion: Bidirectional mandible distraction is an effective treatment for correction of mandible deformities in adult patients.

• The Journal of Korean Physical Therapy
• /
• v.35 no.6
• /
• pp.185-189
• /
• 2023

Purpose: This study investigated the immediate biomechanical effects of unilateral mastication for 10 minutes on the temporomandibular joint (TMJ) with 21 healthy adult participants. Methods: The gum group chewed gum on the right side for 10 minutes, and the control group rested for 10 minutes. Biomechanical data were obtained using a three-dimensional infrared camera before and after intervention. An independent t-test assessed the variation of kinematic data to identify differences between before and after intervention. Results: Among biomechanical variables, the gum group's length of the left forehead middle region and the temporomandibular joint angle decreased compared to the control group (p<0.05). Conclusion: Caution with unilateral masticatory activity is recommended, as unilateral mastication causes biomechanical changes due to excessive load on the soft tissues of the contralateral TMJ.