• The korean journal of orthodontics
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• v.46 no.1
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• pp.27-35
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• 2016

Objective: The aims of our study were to verify the validity of the T-Scan III system (Tekscan) as an objective occlusal evaluation tool, and to assess the differences between two occlusal indexes - the peer assessment rating (PAR) index and the American Board of Orthodontics objective grading system (OGS) - by comparing the scores derived from the T-Scan III system with the two occlusal indexes and analyzing the correlations between them. Methods: The final study sample included 48 adult volunteers (39 men and 9 women, mean age $24.14{\pm}3.16years$), after excluding 29 volunteers whose occlusion could not be evaluated by the T-Scan III system due to severe skeletal or occlusal problems. PAR index and OGS scores were assessed using dental study models, and measurements of centric occlusion, protrusive movement, and lateral excursion movement were obtained via the T-Scan III system. The results were analyzed to determine correlations. Results: Occlusal analysis by the T-Scan III system was clinically reliable (p < 0.05), and the PAR index and OGS scores were significantly correlated with several measurements obtained with the T-Scan III system (p < 0.05). Conclusions: The T-Scan III system is a quantitative and reliable method for occlusal evaluation, and represents a potential substitute for occlusal indexes. Compared to the PAR index, the OGS scores of more variables were significantly correlated with the T-Scan measurements.

• Journal of Oral Medicine and Pain
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• v.10 no.1
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• pp.113-124
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• 1985

In order to observe the effect of mandibular orthopedic repositioning appliance (MORA) on body strength, the author measured back muscle strength with Digital Back Muscle DYNAMOMETER (TAKEI KIKI KOGYO Co., Tokyo, Japan) before MORA, 15 days after and 30 days after MORA in 12 men and then analysed them statistically. The subjects were weight-lifting athletes of Seoul Athletic High School without dysfunction of masticatory system. MORA was fabricated at 1.0-1.5rnm isotonically closed position (Myocentric Occlusion Position) from mandibular rest position (Myocentric Rest Position) using Myo-monitor (MyoTronics Research Inc., Seattle, Washington, USA) and-SVT C-II (Tokyo Shizaisha Inc., Tokyo, Japan). The results were as follows : 1. The mean of back muscle strength before MORA was 150 kg, that of 15 days after MORA was 165 kg (4.43% increase than before), and that of 30 days was 175 kg (10.76% increase than before). 2. There was a significant difference among back muscle strength before MORA, 15 days after and 30 days after MORA (P<0.01: repeated measures one-way ANOVA). 3. According to the result of determining mandibular position for MORA fabrication, mandibular rest position after relaxation with Myo-monitor was 3.2mm lower, 1.0mm posterior, and 0.5 mm left from centric occlusion. And the mean of the amount of lateral deviation was 0.7 mm.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.3
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• pp.232-238
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• 2018

Flabby ridges adversely affect the stability of complete dentures. For the management it is suggested that soft tissues reconditioned before making definitive dentures, and modified impression techniques used for the flabby ridges. Also, correct record of centric relation is important in complete dentures. This case of 67-year-old edentulous female patient had atrophied ridges on the mandible and the flabby ridge on the maxilla. Treatment dentures were fabricated using gothic arch tracing method and tissue conditioner. Definitive dentures were made using window opening impression technique, the gothic arch tracing method, and lingualized occlusion. The patient was satisfied with the function and esthetic quality of the new prostheses.

• The korean journal of orthodontics
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• v.32 no.2 s.91
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• pp.91-105
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• 2002

In general, orthodontists make problem lists and treatment plans based on norms of several cephalometric standards. But consideration of dentoalveolar compensation, which tends to maintain normal dental arch relationship in various skeletal jaw relationships, helps orthodontists make more individualized treatment objectives and plans. The purpose of this study was to classify skeletal patterns of normal occlusion samples by cluster analysis and to investigate the dentoalveolar compensation according to skeletal patterns. The subjects were consisted of 125 subjects who were normal occlusion samples at Seoul National University Dental Hospital, Department of Orthodontics. Lateral cephalograms in centric occlusion were traced and digitized. The skeletal patterns of normal occlusion samples were classified into three horizontal groups and three vertical groups by cluster analysis and ANOVA on the skeletal and dentoalveolar measurements among the groups were carried out. The results were as follows ; 1. Anteroposterior and vertical skeletal relationships of normal occlusion samples were very variable. 2. As the mandibular position was anterior to the maxilla, the maxillary incisors inclined more labially, the mandibular incisors more lingually, and the occlusal plane was flattened due to the anteroposterior dentoalveolar compensation. dentoalveolar height was decreased and upper posterior teeth was uprighted to the palatal plane and lower incisors and lower posterior teeth to the mandibular plane. 4. Lower incisors were more strongly associated with the dentoalveolar compensation than upper incisors according to the anteroposterior and vertical skeletal relationship.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.3
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• pp.273-279
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• 2016

Severe tooth wear may lead to pathological changes of pulp, imbalance in occlusion as well as functional and esthetic problems. In this case, 34-year-old male came to the hospital because of generally worn dentition due to attrition and erosion. After evaluation, a full mouth restoration with elevation of the vertical dimension of occlusion was planned. After occlusion was stabilized by an occlusal stabilization appliance, centric relation position was recorded and subsequent provisional restorations were fabricated. After evaluation, a CAD-CAM (computer aided design-computer aided manufacturing) prosthetic restoration was carried out using monolithic zirconia. After 12 months of follow up observation, the patient was satisfied with function and esthetic appearance.

• Journal of Dental Rehabilitation and Applied Science
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• v.20 no.2
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• pp.95-107
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• 2004

The prosthodontic treatment of Class II division 2 malocclusions is challenging. Ideally, these malocclusions should be identified at an early age and corrected with orthodontic treatment; otherwise, the individual develops a habitual position characterized by deep overbite and significant retruded position of mandibular condyle at the TMjoint fossa. This article describes a clinical protocol for the occlusal rehabilitation of patients with Class II div.2 malocclusions. Within this protocol, an occlusal splint was used to locate the most suitable maxillary-mandibular relationship for function and range of motion. The splint increased the vertical dimension and reduced pain on TMjoints. After transfer this relationship to an articulator for fabrication of provisional restorations, the CR position and centric prematurity contact between maxilla and mandible was used to determine the tentative vertical dimension of occlusion(VDO). The amount of elevation of VDO was decided on the articulated model. The provisional restorations were accurately transfered to a patient's mouth in clinical procedures using tattoo points. The final restoration was delivered after some trial periods with provisional restorations. The theory behind this protocol and its associated clinical procedures is presented along with a discussion.

• Journal of Dental Rehabilitation and Applied Science
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• v.39 no.4
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• pp.204-213
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• 2023

Invasive or non-invasive reduction of fractures could be conducted as treatments of traumatic maxillofacial bone fractures. But when suboptimal reduction or malunion of maxillofacial bone fracture occurs, malocclusion could occur as a result of the lost relationship of the mandible and midface. This malocclusion is called post-traumatic malocclusion and orthognathic surgery, orthodontic treatment, selective grinding and prosthetic reconstruction are suggested as treatments for post-traumatic malocclusion after securement of stable TMJ. Stable TMJ is essential for occlusal rehabilitation to prevent occlusal change and relapse of malocclusion. Centric relation and adapted centric posture are suggested as start points of occlusal rehabilitation because they are most stable TMJ position. This case report presents a case in which post-traumatic malocclusion occurred after reduction of panfacial fracture. To rehabilitate full mouth occlusion, selective grinding and prosthetic reconstruction of implant supported fixed prostheses were conducted in centric relation and showed satisfying results in functional and occlusal aspects.

• The korean journal of orthodontics
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• v.24 no.3 s.46
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• pp.587-620
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• 1994

This study was aimed to evaluate the changes in condylar position when severe anterior open bite patients were treated with MEAW. The subjects consisted of 11 patients(21 TMJs) who visited the departement of orthodontics in SNUH, having severe anterior open bite as a chief complain. They were supposed to wear the up and down elastics and MEAW after finishing the leveling. The condylar position was evaluated with individualized corrected tomography in centric occlusion taken before and after treatment. The results were as follows; 1. In the change of condylar position after treatment, there were no statistically significant differences in right and left TMJs. 2. In the change of condylar position after treatment, there were no statistically significant differences in each malocclusion groups. 3. There were no statistically significant differences in percent dispacement of condyle between before and after treatment 4. There were no statistically significant differences in the amount of change in condylar change.

• The Journal of Korean Academy of Prosthodontics
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• v.17 no.1
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• pp.61-66
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• 1979

To investigate the variation of the mandibular rest position according to time, the mandibular rest position was induced by combination of relaxation and swallowing method. The displacement of the incisal point was recorded with the pinpointed miniature lamp luminograph in three dimensions immediately, 30 seconds, and 60 seconds after induction of the mandibular rest position. The Results obtained were as follows 1. Intermaxillary vertical distance measured immediately after induction of mandibur rest position ranged from 1.0mm to 3.9mm And it varied irregularly with time, ranging from 0.1mm to 1.1mm Anteroposterior variance with time ranged irregularly from 0.2mm to 0.8mm 2. The mandibular rest position observed in the frontal plane varied with time to right or left direction, ranging from 0.2mm to 0.5mm from the centric occlusion 3. the mandibular rest position wos not placed definite position but varied spatially in certain range with time.

• Journal of Oral Medicine and Pain
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• v.14 no.1
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• pp.89-103
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• 1989

In order to evaluate the influences of Myo-monitoring on masticatory muscles, Myo-monitoring on 31 normal persons and 30 persons with one more temporomandibular dysfunction symptoms during 45 minutes or above. The author observed velocities of mandibular opening and closing movement, variabilities of mandibular rest position and EMG activities of temporal and masseter muscles. The obtained results were as follows : 1. There were no significant differences on velocities of mandibular opening and closing movement between before and after Myo-monitoring. 2. There were significant differences on vertical dimension and total dimension form mandibular rest position to centric occlusion between before and after Myo-monitoring but no significant differences on anteroposterior and lateral dimension. 3. Activities of temporal and masseter muscles were decreased in Myo-Monitoring. 4. There were disappeared significant differences on EMG activity values between normal and symptom groups after myo-monitoring.