• Journal of Korean Dental Science
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• v.7 no.2
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• pp.66-79
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• 2014

Purpose: To analyze the amount and pattern of tooth movement and the changes in arch dimension of mandibular dentition after orthodontic treatment using a new three-dimensional (3D)-indirect superimposition method. Materials and Methods: The samples consisted of fifteen adult patients with class I bialveolar protrusion and minimal anterior crowding, treated by extraction of four first premolars with conventional sliding mechanics. After superimposition of 3D-virtual maxillary models before and after treatment using best-fit method, 3D-virtual mandibular model at each stage was placed into a common coordinate of superimposition using 3D-bite information, which resulted in 3D-indirect superimposition for mandibular dentition. The changes in mandibular dental and arch dimensional variables were measured with Rapidform 2006 (INUS Technology). Paired t-test was used for statistical analysis. Result: The anterior teeth moved backward, displaced laterally, and inclined lingually. The posterior teeth showed statistically significant contraction toward midsagittal plane. The amounts of backward movement of anterior teeth and forward movement of posterior teeth showed a ratio of 6 : 1. Although the inter-canine width increased slightly (0.8 mm, P<0.05), the inter-second premolar, inter-first molar, and inter-second molar widths decreased significantly with similar amounts (2.2 mm, P<0.05; 2.3 mm, P<0.01; 2.3 mm, P<0.001). The molar depth decreased (6.7 mm, P<0.001) but canine depth did not change. Conclusion: A new 3D-indirect superimposition of the mandibular dentitions using best-fit method and 3D-bite information can present a guideline for virtual treatment planning in terms of tooth position and arch dimension.

• The korean journal of orthodontics
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• v.20 no.3 s.32
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• pp.519-539
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• 1990

It is the aim of this study to observe the distribution of various facial types in class III malocclusion and to characterize the craniofacial features of the very facial types. Cephalometric headptates of a hundred and ten persons showing bilateral class III malocclusion whose mean age was 12.51 years and sixty nine persons of normal occlusion whose mean age was 12.23 years were measured and statistically analyzed. The following summary and conclusions were drawn. 1. Affording the bases for SNA and SNB, $35.45\%$ of sample showed normally positioned maxilla and protruded mandible, $30.00\%$ for retruded maxilla and normally positioned mandible, $15.45\%$ for retruded maxilla and protruded mandible, $10.90\%$ for both maxilla and mandible within normal range and $8.20\%$ for miscellaneous types were arranged in class III malocclusion. 2. $52.72\%$ of sample showed neutrodiveigent, $35.45\%$ for hyperdivergent and $11.81\%$ manifested hypodivergent mandible in class III malocclusion. 3. Providing the bases for facial and mandibular planes, $33.63\%$ of sample showed prognathic and neutrodivergent, $20.90\%$ for mesognathic and hyperdivergent, $17.27\%$ for prognathic and hyperdivergent and $15.45\%$ for mesognathic and neutrodivergent were arranged in class III malocclusion. 4. The class III malocclusion brought out shorter cranial base, smaller saddle angle, and larger articular and genial angle. It showed retropositioned maxilla and forward positioned mandible in spite of no significant differences in linear measurements of mandible. Anterior lower facial height was significantly larger in class III malocclusion, while posterior total facial and anterior total facial heights exhibited no significant differences. 5. It is suggested class III malocclusion was attributed to shorter cranial base, smaller saddle angle, maxillary deficiency and/or retrusion, mandibular excess and/or protrusion, excessive vertical growth of the anterior lower face, and their complex as well.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.32 no.2
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• pp.36-45
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• 2023

The aesthetic appearance of the incisors is essential for a natural and healthy smile, and it is also an important factor for confidence in interpersonal relationships. If there is crowding or protrusion of the anterior teeth, root canal treatment and excessive tooth removal are often required to resolve it in a short period of time. However, it is difficult to achieve sustainable aesthetic results. In this case, orthodontic treatment will be necessary to preserve the remaining tooth structure as much as possible. Middle-aged and elderly patients are often aware of the need for orthodontic treatment, but they are hesitant to use the traditional orthodontic treatment method using brackets because of the social gaze. In this case, clear aligners can be a good option. So, in this article, a case in which aesthetic needs were resolved with clear aligners alone and another case in which satisfactory results were obtained through restorative treatment following clear aligners application are reported.

• The Journal of the Korean dental association
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• v.50 no.1
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• pp.13-21
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• 2012

In an edentulous situation, the dentist must make several determinations when constructing artificial teeth. These include vertical and horizontal relationships of mandible with respect to the maxilla, occlusal form and position, vertical dimension, occlusal relationships during both centric closure and eccentric excursive movements. Artificial teeth are attached to a movable base resting on movable and displaceable living tissue subject to damage. They act as a unit; therefore, they must be arranged to function as a unit. Bilateral balanced occlusion is that stability of the denture is attained when bilateral contacts ex ist throughout all dynamic and static states of the denture during function. Lateral excursion in a balanced scheme implies simultaneous working side and nonworking side contact, while occlusal contacts are maintained on both anterior and posterior teeth as the mandible moves anteriorly into protrusion.

• Journal of Veterinary Clinics
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• v.17 no.1
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• pp.129-133
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• 2000

Based on pathological findings, 5 German shepherds, revealed a mean age of 7.6 years, showing no clinical signs were diagnosed as tracheopathia osteochondroplastica(TOC). Grossly, multiple small-sizecd nodules, appeared as cobble-stones, on the cartilage rings situated in the anterior trachea and the mucosal surface of the epiglottis were showed. Numerous tiny nodules were scattered on the pleural surface of the lung. The vascular walls of the heart were irregular and coarse apearance with calcification. Histopathologically, nodules in the trachea represented an irregular expansion of the underlying tracheal ring with protrusion into the submucosa and consisted of proliferated and calcified cartilage and bone with marrow spaces containing numbers of hematopoietic cells. Pulmonary calcinosis and calcification of the vascular walls of the heart were observed. Our observations suggested that TOC arises form eccondroses and exostoses of the tracheal cartilage rings.

• Journal of the Korean Society of Clothing and Textiles
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• v.18 no.5
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• pp.628-636
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• 1994

One vertical (medianus) and six horizontal (chest, bust, below bust, waist, abdomen and hip) sections of nine healthy pregnant women were examined every month by siliding gauge method during the period from 3rd to loth monthes of pregnancy. In the body changes along the passing months of pregnancy, which were observed by a follow·up measurement, there was little change on the posterior line when viewed using a vertical cross section. On the contrary, there was a great deal of increase on the anterior median line. Particularly, the degree of protrusion was great in the waist and ubilicus area due to pregnancy. At early pregnancy the distance from front to back is much shorter than side to side, however, as pregnancy progressed the front to back distance, on a horizontal cross section, is almost equal to the side to side distance.

• The Korean Journal of Physiology
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• v.3 no.1
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• pp.33-44
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• 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 Yeungnam Medical Science
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• v.5 no.1
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• pp.127-133
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• 1988

Two patients, sought treatment for chief complaints of protruding frontal tooth and desired treatment to reduce the prominance of lips, were diagnosed as bimaxillary protrusion via clinical and cephalometric analysis. The authors corrected them by combined surgical and orthodonic treatment. As pre-surgical survey, paper and cast surgery were performed and wafer and resin sprint were constructed. We performed anterior maxillary and mandibular osteotomies in first premolar site to retract the maxillary and mandibular dentoalveolar segment in order to ; 1) decrease prominance of upper and lower lips. 2) create proper lower incisor intrusion. By use of intrtamaxillary fixation, prompt oral intake was possible. We made good result of esthetic improvement and there was no evidence of relapse and any complication.

• The korean journal of orthodontics
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• v.34 no.5 s.106
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• pp.458-464
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• 2004

Anchorage plays an important role in orthodontic treatment especially in the maxillary arch. In spite of many efforts for anchorage control. it was difficult for clinicians to predict the result of treatment because most of the treatment necessitated an absolute compliance of patients, But recently, skeletal anchorage has been used widely because it does not necessitate patient compliance but produces absolute anchorage. In addition titanium miniscrews have several advantages such as ease of insertion and removal. possible immediate leading and use in limited implantation spaces. In this case, a skeletal Class I bialveolar protrusion Patient was treated with standard edgewise mechanics using indirect active P.S.A. (palatal skeletal anchorage). The miniscrews in the paramedian area of the hard palate provided anchorage for retraction of the upper anterior teeth and remained firm and stable throughout treatment This indicates that the PSA can be used to reinforce anchorage for orthodontic treatment in the maxillary arch Consequently, this new approach can help effective tooth movement without patient compliance, when used with various transpalatal arch systems.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.3
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• pp.199-207
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• 2013

Purpose: The importance of occlusal contacts of the natural dentition for durability of teeth, mandibular stabilization, and restorative dentistry is well known. The purpose of this study is to analyze the occlusal contact and guidance pattern of Koreans by evaluating the static occlusion on maximal intercuspal position and measuring dynamic occlusion during straight protrusion. Materials and methods: The occlusal contacts at maximal interincisal position and the occlusal guidance pattern during straight protrusion of 29 subjects were recorded with shimstock foil (Whaledent, Langenau, Germany), T-Scan III (Tekscan Inc., Boston, MA, USA), polyvinylsiloxane registration material (Genie Bite, Sultan Healthcare, Hackensack, NJ, USA) and compared. Occlusal registration procedures were repeated 3 times. The position was fixed to an upright position and the head position was fixed with the Frankfurt horizontal plane paralleling the horizontal plane. Fisher's Exact Test (R-General Public License, ver. 2.14.1) and Pearson's Test were used to assess the significance level of the differences between the experimental groups (${\alpha}=.05$). Results: When using shimstock foil, T-Scan III system, and polyvinylsiloxane registration material, most of the patients showed contact on anterior, premolar, and molar teeth during maximal intercuspal position. Approximately 51% of maximal intercuspal position showed anterior contact using shimstock foil. When examining the protrusive movement using shimstock foil and T-Scan III system, guidance pattern with the central incisor was the most common. Conclusion: During maximal intercuspal position, there were cases in which not all of the teeth showed occlusal contact. During mandibular protrusive movements, one or more maxillary central incisors frequently joined in straight protrusion and the posterior teeth were disoccluded. Therefore, the anterior teeth protect the posterior teeth, and vice versa. Thus, mutually protected occlusion should be applied when reconstructing occlusion.