• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.1
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• pp.134-143
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• 1998

Twin Blocks are simple bite-blocks that effectively modify the occlusal inclined plane to induce favorably directed occlusal forces by causing a functional mandibular displacement. These devices use upper and lower bite-blocks that engage on occlusal inclined planes. Twin Blocks use the forces of occlusion as the functional mechanism to correct the malocclusion. To get an excellent result in the treatment by using the Twin Block appliances, proper case selection must be needed. Twin Block treatment is performed in two stages. Twin Blocks are used in the active phase to correct the anteroposterior relationship and establish the correct vertical dimension. Once this phase is accomplished, the Twin Blocks are replaced with an upper Hawley type of appliance with an anterior inclined plane, which is then used to support the corrected position as the posterior teeth settle fully into occlusion. The Twin Block is the most comfortable, the most esthetic ane the most efficient of all the functional appliances. Twin Blocks have many advantages compared to other functional appliances. Patients can wear Twin Blocks 24 hours per day and can eat comfortably with the appliances in place. From the moment Twin Blocks are fitted, the appearance is noticeably improved. There is less interference with normal function. Integration with conventional fixed appliances is simpler than with any other functional appliance. Twin Blocks allow independent control of upper and lower arch width. Appliance design is easily modified for transverse and sigittal arch development. The authors treated Class II malocclusion with Twin Blocks. and the results as follows; 1. Rapid profile improvement was achieved in 2-3 months. 2. There was excellent patient cooperation. 3. Severe overjet and overbite were reduced. 4. Class II molar relationship was changed to Class I.

• The Journal of Korean Academy of Prosthodontics
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• v.53 no.1
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• pp.39-45
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• 2015

Loss of continuity of the mandible destroys the balance and symmetry of mandibular function, leading to altered mandibular movements and deviation of the residual fragment towards the resected side. Apart from deviation, other dysfunctions include difficulty in swallowing, speech, mandibular movements, mastication, and respiration are accompanied. In general, surgical reconstruction is considered first then proceeds to the prosthetic restorations. However, patients with systemic disease such as BRONJ (Bisphosphonate related osteonecrosis of the Jaw), surgical reconstruction may be limited. Thus, the prosthetic restoration remains as the only resort. Numerous prosthetic methods are employed to minimize deviation and to improve masticatory efficiency, function and esthetics. If a removable partial denture is the selected treatment modality, maximum stability of the partial denture base may be accomplished with a functional impression procedure by means of eliminating lateral and horizontal forces caused by the functional movements of the lips, cheeks and tongue. Also, Twin occlusion is used to obtain a favorable occlusal relationship and check support for esthetics. The purpose of this case report is to demonstrate how neutral zone impression technique and twin occlusion scheme were applied to restore a hemi-mandiblectomy patient with BRONJ syndrome to achieve satisfactory results in functional and esthetic aspects.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.3
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• pp.291-297
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• 2016

Patients with $Sj{\ddot{o}}gren^{\prime}s$ syndrome usually suffer from teeth discoloration and attrition due to xerostomia. If the anterior teeth are badly worn, problems such as loss of anterior guidance, occlusal disharmony, and limited space for restoration may occur. However, ideal occlusion is obtained in both centric and eccentric relation by regaining the disocclusion of the posterior teeth through the anterior and lateral guidance using twin-stage method. In this case, rehabilitation was performed for a $Sj{\ddot{o}}gren^{\prime}s$ syndrome patient with maxillary and mandibular incisor's severe attrition and teeth discoloration by using twin-stage method.

• The Journal of the Korean dental association
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• v.13 no.4
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• pp.335-337
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• 1975

The auther observed the oral status of the 14 twins clinically, the obtainde results were as follow : 1. In each twins, the color of the teeth, the form of the uper central incisors, the periodontal conditions and the oral hygiene status were resemble each other. 2. In one twin, the dentition and the size of the palatine tonsil were different each other. 3. In two twins, the occlusion and the number of the dental caries were different each other. 4. In four twins, the eruptions of teeth were different each other.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.197-205
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• 2020

Compared to aerial photogrammetry, UAV photogrammetry has advantages in acquiring and utilizing high-resolution images more quickly. The production of 3D models using UAV photogrammetry has become an important issue at a time when the applications of 3D spatial information are proliferating. Therefore, this study assessed the feasibility of utilizing 3D models produced by UAV photogrammetry through quantitative and qualitative analyses. The qualitative analysis was performed in accordance with the LODs (Level of Details) specified in the 3D Land Spatial Information Construction Regulation. The results showed that the features on planes have a high LoD while features with elevation differences have a low LoD due to the occlusion area and parallax. Quantitative analysis was performed using the 3D coordinates obtained from the CPs (Checkpoints) and edges of nearby structures. The mean errors for residuals at CPs were 0.042 m to 0.059 m in the horizontal and 0.050 m to 0.161 m in the vertical coordinates while the mean errors in the structure's edges were 0.068 m and 0.071 m in horizontal and vertical coordinates, respectively. Therefore, this study confirmed the potential of 3D models from UAV photogrammetry for analyzing the digital twin and slope as well as BIM (Building Information Modeling).