• Journal of Digital Convergence
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• v.15 no.10
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• pp.307-314
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• 2017

In this study, a minimum amount of the vertical occlusion was secured differently in each type of mandibular advance devices snoring and Class I malocclusion patients wore these devices. This study analyzes, after the use of devices, a different amount of the vertical occlusion results in a change of the area of upper airway by additional changes such as mandibular position, muscle changes, tongue position. The higher the vertical amount, the area of the upper airway was shown smaller, And if the patient's tongues was prevented from the distal movement, the area of the upper airway had increased, To reduce snoring, doctors should accurately diagnose patients' occlusal relationships and select a MAD snoring that is appropriate for the occlusion. The dental technician who builds the selected device should also consider design settings such as the amount of vertical occlusion, the finish lines, and the thickness of the device to increase the effectiveness of the device.

• Journal of Biomedical Engineering Research
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• v.22 no.6
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• pp.551-557
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• 2001

Occlusion of the dural-sac in the lumbar spine was quantitatively analysed using a one motion segment finite element mode developed in this study. Occlusion was quantified by calculating the cross sectional area chance of the dural-sac. In static analysis. less than 2 kN of compressive load could Produced no dural-sac occlusion. whereas 6kN load reduced cross sectional area by 4%, and produced 7.4%, 10.5% occlusion for additional 8 Nm. 10 Nm extension moments. respectively. In creep analysis, 10 Nm extension reduced cross sectional area and volume of the dural-sac by 6.9% and 2.4%, respectively. However. flexion moment could not produce any occlusion. The results suggested that occlusions may result mainly from slackening of ligamentum flavum and disc budging.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.3
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• pp.262-272
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• 2015

Loss of molar support and abnormal jaw relationship lead to occlusal disharmony and cause pathologic signs. Full mouth rehabilitations with reestablishment of occlusal schemes are needed. In this case, the 75 year-old female patient showed posterior bite collapse, irregular occlusal plane and Class II jaw relationship. By observing her profile and interocclusal distance, she was diagnosed as loss of occlusal vertical dimension. Treatment plan is to restore maxillay class I removable partial denture and mandibular fixed prosthesis and to establish vertical dimension and harmonious occlusal plane. Occlusal vertical dimension of 19 mm, which is obtained by 7.5 mm increase between maxillary right lateral incisor and mandibular canine, was established using temporary prosthesis via diagnostic wax-up. Patient adaptation with newly formed vertical dimension was verified during 8 week follow-up period. Within the information of interim prostheses, final restoration was constructed and delivered. The patient showed sound occlusal scheme and esthetic profile.

• The korean journal of orthodontics
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• v.30 no.4 s.81
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• pp.491-507
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• 2000

The purpose of this study was to investigate if there were a significant differences in mandibular position between cephalometric measurements from a centric occlusion tracing compared to those of a acquired centric relation by stabilization splint on malocclusion patient with TMD. 60 malocclusion patients, who had TMD and CO-CR discrepancy beyond normal range, were selected and subdivided into Class I, II, III by Angle's classification and also subdivided into clockwise, straight downward, and counterclockwise group by Jarabak's posterior facial height/anterior facial height ratio. Lateral cephaolmetric radiographs with the mandible in centric occlusion were taken and measured, and for each Patient the stabilization splint with mutually protected occlusal scheme was applied for minimum 3months. After each patient's CO-CR discrepancy was in normal range, lateral cephalometric radiographs were retaken and measured. The comparison of the difference between CO-CR cephalometric measurements in all sample, Class I, II, III groups, and Clockwise, Straight downward, Counterclockwise groups were studied. The finding of this study can be summarized as follows: 1 In all sample, the value of cephalometric measurements was significantly different between CO-CR. The mandible rotated to down and posterior position and the vertical change was greater than the horizontal change (overjet-1.3mm increase, overbite-1.9mm decrease). 2. In Class II malocclusion group, most of the mean difference value between CO-CR is higher than that of the other groups and more measurements was statically significant. 3. In clockwise and counterclockwise group, some of the mean difference value is higher than that of straight downward group and more measurements was statically significant. 4. There ware no measurements that explain centric relation measurements from the type of malocclusion, facial pattern and centric occlusion measurements. Henceforth, it is strongly recommended that stabilization splint therapy for orthodontic treatment on TMD patient should be excuted upon overall facial types prior to orthodontic diagnosis and treatment planning.

• The Journal of Korean Academy of Prosthodontics
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• v.58 no.2
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• pp.110-120
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• 2020

Although not all kinds of deep bite occlusions are considered pathological states, they can cause persistent wear and eruption of the anterior mandibular teeth if the anterior occlusal contact is unstable or accompanied by an occlusal disharmony. The patient was a 72-year-old man with no occlusal contact of the remaining anterior teeth in the centric relation position because of a skeletal class II malocclusion and loss of occlusal support. If the vertical dimension needs to be increased for prosthetic restoration in a patient with a deep bite, the amount of vertical dimension increase must be determined through precise diagnosis. This is because the overjet may increase and cause an unstable occlusion. In this review, we report the case of a patient with a stable occlusion and good treatment results achieved by using a removable partial denture prosthesis and applying the Dahl concept.

• The Journal of Korean Academy of Prosthodontics
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• v.58 no.1
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• pp.50-57
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• 2020

The loss of posterior support and the abnormal jaw relation can cause pathologic findings. If deep bite patients with multiple missing teeth, can not have the stable posterior contact, the mandible moves posteriorly, and consequently the overjet and overbite get worse. And when the mandibular irregular occlusal plane is corrected, it is easier to have the bilateral balanced occlusion with the maxilla. So the treatment goal is to give proper posetrior support and establish appropriate anterior guidance, and ultimately provide improved mastication and esthetics recovery. In this case, a 68 year old man, having deep bite without posterior support was evaluated by the vertical dimesion decision flow-chart. An available prosthetic height, anterior occlusal relation such as overjet, overbite and the esthetic part such as facial height and the cephalometric analysis are the factors to be considered.

• The korean journal of orthodontics
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• v.38 no.1
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• pp.31-40
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• 2008

Objective: This study investigated the skeletal and dentoalveolar changes after intrusion of maxillary posterior teeth using miniscrew implants during the treatment and posttreatment period. Method: The subjects consisted of 11 adults (1 male, 10 females) whose open bites were treated by posterior teeth intrusion with miniscrew. The lateral cephalometric x-rays of pre-treatment, post-treatment, and the retention period were evaluated. Results: The average intrusion of maxillary posterior teeth at the end of the treatment period was 2.22 mm (p < 0.001) and the average extrusion of maxillary posterior teeth at the end of the 17.4 month retention period was 0.23 mm (p = 0.359). The relapse rate was calculated at 10.36%. A decrease in overbite after the 17.4 month retention period was 0.99 mm (p < 0.05). The relapse rate was calculated at 18.10%. The skeletal changes and vertical height change of maxillary posterior teeth during the retention period was statistically insignificant, but there was a significant decrease in overbite (mean 0.99 mm, p < 0.05). The amount of intrusion and the overbite improvement from treatment significantly correlates to the degree of relapse. Conclusions: The results indicate that intrusion of the maxillary posterior teeth using miniscrews is an effective, non-surgical treatment modality which can reasonably be used to address adult open bite.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.1
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• pp.1-7
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• 2016

Purpose: The aim of this study was to evaluate the effect of increased vertical dimension of occlusion on lower facial changes by facial type. Materials and methods: Lateral cephalograms from 261 patients were obtained and classified by sagittal (Class I, II, and III) and vertical (hypodivergent, normodivergent, and hyperdivergent) facial patterns. Retrusive displacement of soft tissue Pogonion and downward displacement of soft tissue Menton were measured in each group after 2 mm of vertical dimension of occlusion was increased at the lower central incisor using a virtual simulation program. The ratio of both displacements was calculated in all groups. The statistical analysis was done by 2-way ANOVA and Post hoc was done by Tukey test (5% level of significance). Results: Retrusive displacement of soft tissue Pogonion in Class III group was statistically different compared to Class I and II, and in vertical facial groups all 3 groups were significantly different (P<.05). Downward displacement of soft tissue Menton showed statistically significant difference between all sagittal groups and vertical groups (P<.05). The ratio of both displacements showed statistically significant difference in all sagittal groups and vertical groups (P<.05), and Class II hyperdivergent group had the highest value. Conclusion: Lower facial change was statically significant according to the facial type when vertical dimension of occlusion increased. Class II hyperdivergent facial type showed the highest ratio after increase in vertical dimension of occlusion.

• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.4
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• pp.477-482
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• 2010

In a case of multiple posterior teeth loss, antagonistic teeth extrude to the edentulous space and compensatory occlusion on the remained anterior teeth leads to occlusal trauma. Extrusion of antagonistic teeth breaks down occlusion plane and loss of posterior support bring about severe wear of remained teeth. In this situation, it is needed to restore remained teeth and edentulous space by increasing vertical dimension to obtain prosthodontic rehabilitation space and to correct occlusion plane. In this case report, the patient had a masticatory problem with loss of posterior teeth support and an esthetic problem of shortened anterior teeth. Before the tooth preparation for the prosthodontic restoration, the patient used removable device for 2 months to increase vertical dimension reversibly. After that, he got provisional fixed restoration with irreversible tooth reduction and used it for 3 months. It had spent 5 month to evaluate the adaptation state on final restoration with incresed vertical dimension. The increasing amount was 3 mm, which was relatively in less degree and masticatory system adapted to the increased vertical dimension without any pathologic changes. Final restoration was made to have equal-intensity contacts on all teeth in a verifiable centric relations and immediate disclusion of all posterior contacts the moment the mandible moves in any direction from centric relation. In addition, metal occlusion surface on posterior teeth was applied to prevent excessive muscle activation, occlusal trauma and the porcelain fracture.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.2
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• pp.143-152
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• 2023

Although tooth wear is a normal process due to aging, severe tooth wear causes various complications such as increased tooth sensitivity, loss of tooth structure, and pulp complications. In the treatment of patients with excessive tooth wear, the evaluation of loss of vertical occlusal dimension should be prioritized. If it is necessary to increase the vertical dimension to secure the restoration space, it is important to establish a treatment plan with the comprehensive analysis and determine the minimum vertical dimension elevation. In this case, 66-year-old male patient with severe worn dentition wanted to restore masticatory function and improve esthetic restoration. In order to determine the appropriate vertical dimension of the patient, we evaluated oral examination, radiographic examination, and diagnostic cast examination, and performed rehabilitation with minimum vertical dimension elevation. As a result of observation for 8 months, the definitive prosthesis was completed with contact of all teeth in centric occlusion, and proper anterior/posterior guidance. Through the above process, satisfactory aesthetic and functional outcomes were obtained.