• The korean journal of orthodontics
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• v.30 no.1 s.78
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• pp.91-99
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• 2000

This study was done to identify the changes of bite force and occlusal contact between before and after stabilization splint therapy. 16 female patients, accepted for orthodontic treatment at the Department of Orthodontics, College of Dentistry, Chosun University, were selected as the sample of this investigation. For comparisons, the samples of 16 were divided into just before stabilization splint, 1 month after stabilization splint, 2 months after stabilization splint, and 3 months after stabilization splint and used the T-scan system to identify the bite force and occlusal contact changes for each group. Statistical analysis of the data was carried out ANOVA tests, and Turkey tests using $SPSS/PC^+$. The results were as follows : 1. Bite force change from just before treatment to 1 month after stabilization splint therapy was statistical significantly decreased (P<0.05). 2. Bite force changes from 1 to 3 months after stabilization splint therapy showed no statistical significance (p>0.05). 3. The changes of anterior occlusal contacts showed no statistical significance regardless of the wearing periods of stabilization splint (P>0.05). 4. The changes of posterior occlusal contacts from just before treatment to 1 month after stabilization splint therapy was statistical significantly decreased (P<0.05). 5. The changes of posterior occlusal contacts Outing 1 to 3 months after stabilization splint therapy showed no statistical significance (P>0.05). 6. Posterior teeth rather than anterior teeth were more influenced by the changes of the number of occlusal contacts. To sum up above results, we may respect to capturing and stabilizing centric relation Position just 1 month after stabilization splint therapy.

• Journal of Oral Medicine and Pain
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• v.37 no.4
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• pp.205-211
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• 2012

A 35 year-old female presented with the complaint of sudden occurrence of bite change and concurrent opening limitation, as well as pain in the right temporomandibular joint (TMJ) during mouth opening. From her history it was revealed that she had simple clicking of right TMJ for several years before onset of these symptoms, and that the clicking sound subsided recently after development of opening limitation. On clinical examination, anterior open bite, midline shift of the mandible to right, and premature contacts on left posterior teeth were observed. Maximum mouth opening and lateral movement to left were also restricted. On magnetic resonance images, the right TMJ showed anterior disc displacement without reduction and the posterior joint space is greatly collapsed by retrusion of the condyle. It was thought that the sudden occurrence of occlusal change would be resulted from abrupt displacement of the mandible associated with development of the anterior disc displacement without reduction. The stabilization appliance traction therapy was performed initially for first 3 months along with physical and pharmacologic therapy. However, the anterior open bite and opening limitation didn't resolve and the position of mandible still remained altered. So the stabilization appliance was changed to intermaxillary traction device. Then the mandible returned progressively to normal position and the occlusion became more stable and comfortable. After 5 months of intermaxillary traction therapy, the anterior open bite was dissolved completely and the occlusion became stabilized satisfactorily along with recovery of normal mouth opening range. On post-treatment magnetic resonance image, remodeling of condylar head was observed.

• Journal of Oral Medicine and Pain
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• v.38 no.2
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• pp.149-159
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• 2013

The purpose of this study was to investigate the relationship between horizontal morphology of lateral pterygoid muscle and onset of temporomandibular joint disorders. Randomly selected 150 subjects, assigned with equal number in terms of gender and age group, were included. The axial and sagittal images in their magnetic resonance images of the temporomandibular joints were used to measure the morphologic characteristics of lateral pterygoid muscles and temporomandibular joints. The measurement variables were maximal horizontal width and insertion angle to the condyle, position of the articular disc, condylar deformity, and joint effusion. In addition, presence or absence of the temporomandibular joint pain was examined through history and palpation of the joints. The relationships among measurement variables were analyzed and the results were as follow. The insertion angle of the lateral pterygoid muscle to the condyle was higher in the joint of anterior disc displacement without reduction than that in the joint of normal disc position. In addition, the maximal horizontal width of the lateral pterygoid muscle was significantly increased in joints with pain than those without pain. Also, the insertion angle was significantly higher in younger age group and the maximal width was significantly greater in male than in female. These results suggest that high insertion angle of lateral pterygoid muscle might be an important anatomic predisposing factor for anterior disc displacement in temporomandibular joint and muscular activity of lateral pterygoid muscle might be affected by preauricular pain. In conclusion, there might be a bi-directional interaction between lateral pterygoid muscle and joint in the progression of anterior disc displacement in temporomandibular joint.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.4
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• pp.249-256
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• 2022

The implant prosthesis of anterior maxilla requires careful consideration in planning. In order to satisfy both esthetic and functional needs of a patient, fusion of intra-oral scan in Cone-beam computed tomography (CBCT) and facial scan can be considered. Bony structures and soft tissues captured in CBCT and occlusal surfaces of intra oral scan were incorporated into personal characteristics from facial scan. The patient had insufficient buccal bone on maxillary anterior area. The maxillary implants could not be placed on the most ideal position. However, the "top down" approach completed by computer-generated arranging of teeth in implant planning and surgery with surgical guide resulted in esthetically and functionally satisfying result regardless of the limitation. Careful diagnosis with digital technique and the usage of surgical guide resulted in successful surgery and esthetic restoration. The temporary fixed prostheses were designed, restored and evaluated. The patient was not satisfied with the first design of temporary prosthesis, which showed uneven space distribution between teeth due to the position of maxillary implant. The design was modified by changing proximal emergence contours and line angle to alter the perceived since of incisors. The patient was satisfied with the new design of provisional restoration. A digital occlusion analyzer (Arcus Digma II, KaVo, Leutkirch, Germany) was used to measure inherent condylar guidance and anterior guidance of a patient to provide a definitive prosthesis.

• Journal of Oral Medicine and Pain
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• v.37 no.4
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• pp.221-225
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• 2012

Disc dislocation without reduction, as known as closed lock, is a clinical condition in which the disc is dislocated from the condyle and does not return to normal position during condylar movement When the condition of disc dislocation without reduction is acute, the initial therapy should include an attempt to reduce or recapture the disc by manual manipulation. When patients report a history of being locked for 1 week or less, manual manipulation is usually successful. In patients with a longer history, success rate tends to decrease rapidly. If the disc has been successfully recaptured, placing an anterior positioning appliance is recommended to prevent clenching on the posterior teeth, which would likely redislocated the disc. But it is hard to make an appliance immediately in the clinic because it takes too much time. And making an appliance using self-curing acrylic resin is not very popular because of its discomfort by odor and working time. Also, if the patient has resin allergy or is under orthodontic treatment, or if it is impossible to control behavior of the patient, it has been restricted to make an appliance immediately. Therefore, to supplement this disadvantages, we tried to confirm about successful short term use of temporary anterior positioning splint made by using putty impression material after manual manipulation in this study.

• Journal of Oral Medicine and Pain
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• v.38 no.1
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• pp.29-34
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• 2013

Objective: All patients who have the disc displacement with reduction (DDwR) are always not progressive but some of them with significant catching or locking progress to disc displacement without reduction (DDw/oR). In this study, we suggest opening exercise therapy using Locking-free Appliance (LA) to be helpful to prevent progressive derangement. Methods: Retrospectively, a total 37 patients who received exercise treatment using LA was analyzed from January 2010 to December 2011. Patients had been instructed in proper exercise technique to practise for opening and closing of mouth wearing the appliance 30 times a day in locking-free position. Results: None of the patients took a turn for worse to DDw/oR (37 patients). The 16 patients (43.2%, locking-free group) of them could open their mouth without intermittent condylar locking. Measurement of data was analyzed using and Mann-Whitney test. There was no statistically significant difference for age, gender, presence of palpational pain, locking period, VAS quantitative pain score between locking-free group and locking group. Conclusions: In this study, some patients could open their mouth without intermittent locking and did not take a turn for worse to DDw/oR after opening exercise therapy with LA. Furthermore, LA had advantages which were short wearing time, low costs and minimizing patients' uncomfortable compared to conventional treatment method. This therapy can be more appropriate new treatment to prevent progress to DDw/oR.

• Journal of Dental Rehabilitation and Applied Science
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• v.16 no.2
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• pp.133-147
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• 2000

A well-planned, precise occlusal adjustment of natural teeth has some distinct advantages over other forms of occlusal therapy. It should be emphasized, however, that an occlusal adjustment is an irreversible procedure and has definite contraindications in some mouths. Generally, the treatment methods for the patients that has open-bite will be following as below. : (1) Use of removable orthopedic repositioning appliance, (2) Orthodontics, (3) Full or partial reconstruction of the dentition, (4) Orthognathic surgical procedure, (5) Occlusal adjustment of the existing natural teeth, (6) Any combination of the above. Above all, the advantages of occlusal adjustment of natural teeth are : (1) the patient is more able to adapt to the changes in jaw position and posture; (2) the phonetic or speaking ability of the patient is not significantly changed and usually is improved; (3) the esthetics of the natural teeth is not altered and often is better; (4) the hygiene of the individual teeth is easily maintained; and (5) the functional usage of the teeth as cutting and chewing devices is markedly improved. The objective of an occlusal adjustment, as with any form of occlusal therapy, is to correct or remove the occlusal interferences, or premature contacts, on the occluding parts of the teeth which prevent a centric relation closure of the mandible. A systematic, disciplined approach can be followed in treatment, the objectives should be listed. They are : (1) Centric relation occlusion of the posterior teeth. (2) Proper "coupling" of the anterior teeth. (3) An acceptable disclusive angle of the anterior teeth in harmony with the condylar movement patterns. (4) Stability of the corrected occlusion. (5) Resolution of the related symptoms. For the patient with open-bite on anterior and posterior teeth, this case report shows the treatment methods in combination the fixed prosthesis with the selective cutting of the natural teeth. Occlusal adjustment is no longer an elective procedure but a mandatory one for patients requiring restorations and those in treatment for TMD dysfunctions or those whose dentitions show signs of occlusal trauma. Occlusal adjustment is essential for all who do not display the above lists.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.1
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• pp.33-43
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• 2023

Pathological wear across the entire dentition causes problems such as collapsed occlusal plane, reduced vertical dimension, anterior premature contact, inadequate anterior guidance, and tooth migration, thereby induce symptoms such as temporomandibular joint disorder, reduced masticatory efficiency, and tooth hypersensitivity. For the treatment of patients with excessive wear, evaluation of vertical dimension should be preceded along with analysis of the cause. The patient in this case was a 45-year-old female with a history of orthognathic surgery. Through clinical examination, radiographic examination, and model analysis, overall tooth wear, interdental spacing in the anterior maxillary region, retruded condylar position, and insufficient interocclusal space for prosthetic restoration were confirmed. Full mouth rehabilitation with increased vertical dimension was planned, the patient's adaptation to the new vertical dimension was evaluated with a removable occlusal splint and temporary prosthesis, and cross-mounting was performed based on the temporary restoration to fabricate the definitive zirconia prosthesis, maintaining the adjusted vertical dimension. It showed satisfactory functional and esthetic results through stable restoration of the occlusal relationship.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.4
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• pp.487-496
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• 2021

Full mouth rehabilitation is re-organizing the occlusion of the remaining teeth and missing teeth considering the functions, esthetics, and neuromuscular harmony. With the loss of multiple teeth, the patient's occlusal plane gradually collapses and the vertical dimension can be reduced. Since reduced vertical dimension can be a potential etiology of the temporomandibular joint and masticatory muscles, prosthetic restoration with increased vertical dimension is required. This case report is about a 68 years old patient with vertical dimension loss due to worn dentition and multiple loss of teeth. In this case, the loss of vertical dimension is assessed carefully using the digital dentistry technology. Using CAD software in digital analysis step, the occlusal plane was established and evaluated using several criteria. Orienting the position of the bone and teeth using CBCT image, patient's condition was visualized in 3 dimension and treatment planning was possible virtually. The information that matches the patient's condylar position with the articulator, which is the virtual face bow, is reproduced on the actual articulator, and evaluated again. After the evaluation, provisional prosthesis was fabricated and it was confirmed that the patient adapts without any abnormality. This was implemented as a final prosthesis. As a result, the patient obtained satisfying results, utilizing the benefits of digital dentistry technology and traditional methods.

• The korean journal of orthodontics
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• v.28 no.5 s.70
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• pp.839-853
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• 1998

The present study was performed to prove the relationship between CO-CR discrepancy and facial skeletal type. In this study, 242 subjects were randomly selected and devided into 9 groups(devided into class I, II, III by ANB and each one devided into dolicho-, brachy-, mesofacial skeleton by Ricketts' vertical index). Lateral cephalometric radiographs with the mandible in centric occlusion were taken and measured and CO and CR bites were registered on all subjects. Diagnostic casts were mounted on Panadent articulator using an estimated face-bow and centric relation bite registration. The amount and direction of CO-CR discrepancy present was recorded using a Condylar Position Indicator(CPI) and a centric occlusion wax bite registration. CPI measurements and cephalometric measurements were statistically analyzed. The finding of this study can be summerized as follows : 1. There is little correlation between right and left sides for magnitude or direction of CO-CR discrepancies. The correlation between the magnitude of CO-CR discrepancy of left A-P and right A-P is higher than that of left S-I and right S-I. 2. Correlation of Class II malocclusion group was higher than that of the other groups between the magnitude of CO-CR discrepancy of left CPI and right CPI. 3. There is no difference between the pattern of CO-CR discrepancy of 9 malocclusion groups. 4. There is very little, if any, correlation between Skeletofacial measurements and CO-CR discrepancy. 5. In Class II brachyfacial skeleton and Class III mesofacial skeleton there was Lateral cephalometric measurements by that we predict CPI measurements was detected. That was overbite, overjet, upper genial angle, lower genial angle, saddle angle, articular angle, convexity of point A, ANS-Me/Na-Me, PCBL/RH, Posterior FH/anterior FH.