• The korean journal of orthodontics
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• v.37 no.4
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• pp.260-271
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• 2007

The purpose of this study was to evaluate the relationships between the occlusal plane angle and craniofacial skeletal pattern in relation to anterior overbite. Methods: Lateral cephalograms of 90 adults with skeletal class III malocclusions were traced and measured to analyze skeletal factors and occlusal plane angles. In terms of anterior overbite, all patients were classified into 3 subgroups of positive overbite, edgebite, and negative overbite groups. All measurements were evaluated statistically by ANOVA and Duncan's Post Hoc, and correlation coefficients were evaluated among measurements. Results: In this study, some skeletal measurements (saddle angle, articular angle, Y axis, AFH, SN-FH, SN-Mn, FH-Mn) showed a significant difference among the 3 groups in relation to overbite changes. Correlation coefficient showed that PFH/AFH, SN-Mn, Mx-Mn, and FH-Mn showed a significant difference with FH-Occ, Mx-Occ, and Mn-Occ. Regression analysis showed that Mx-Mn had a determination coefficient of 0.714, 0.560, and 0.677 in relation to FH-Occ, Mx-Occ, and Mn-Occ, respectively. Conclusion: This study suggests that consideration of the occlusal plane in relation to the maxillomandibular vertical skeletal state enable the establishment of a more predictable orthognathic surgery result.

• Parasites, Hosts and Diseases
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• v.27 no.2
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• pp.141-144
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• 1989

During October-December 1987, chigger mites infested on the striped field mice (Apodemus agrarius cereae) collected at Pochun-gun, Gyeonggi Province and Chinhae city, Kyongnam Province were identified. . 1. Of 171 back-striped mice collected, chigger mites wire found from 58 mice, showing 33.9% of infestation rate. 2. Total 865 chigger mites collected were classified into seven species; Leptotrombidium pallidum (4.3%), L. palpate(23.0%), L. orienpalis(20.2%), L. xetum(19.0%), Neotrombicula tamiyai(32.9%), JV. japonica(0.25%) and Euschongastia koreaensis(0.3%). Though the most dominant species in number was N. tamiyai(32.9% of the total), this species was collected at very limited locality and for a short period. Therefore, most common species in Korea seems to be L. palpale which was found at all localities throughout the whole survey period. L. pallidum which is known as the vector species of tsutsugamushi disease in Korea was collected in a very low number(4.3% of the total chiggers collected). 3. The number of chigger mites infested on a host animal showed great variations from one chigger up to 207 chiggers. The present study has shown that there may be other Leptotrombidium species mite(s) for the vector and host of tsutsugamushi disease in Korea.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.3
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• pp.246-253
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• 2016

The optimal time for the removal of supernumerary teeth can be divided into two groups; early removal and late removal. While each group has its own advantages, the effects on maxillary central incisor can be significant. The purpose of this study was to determine the ideal time for the removal of the supernumerary teeth by evaluating 166 patients for three months after surgical removal of supernumerary teeth. Relatively young patients in early Hellman's dental stage with less developed or unerupted maxillary central incisor had less midline deviation. No statistical significance was found in diastema, rotation of the maxillary incisors and their changes during a follow-up period. Removal of supernumerary teeth should be considered as a preventative measure prior to eruption of the maxillary incisors when the midline deviation is observed in panoramic radiographic examination. This study will be useful in determining the optimal time for the removal of supernumerary teeth depending on the location of the maxillary incisors. This study will be informative on deciding the optimal time to remove the supernumerary teeth depending on the various positions of the maxillary central incisor. (this sentence is better to use)

• Journal of Oral Medicine and Pain
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• v.32 no.1
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• pp.57-67
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• 2007

In currently, stress diseases are increased that present several sign and symptoms. Under stress condition, there are dry mouth, burning mouth syndrome, oral mucosa diseases and halitosis more frequently. Changing of salivary proportion is checked in almost patients with changing of function and structure in salivary gland. This study purpose are what effect stress does on salivary gland, and a-amylase on salivary gland. This study was resulted that 1. Under restraint stress, acinar cells are vacuolization and changing of intercellular spaces are separated, and peripheral tissues of duct are changed 2. Acinar cells were shrunk after 3 hours under restraint stress, intercellular space was separated after 6hours, peripheral tissues of duct started to change after 72 hours, and acinar cells and peripheral tissues of duct were all severely changed after 168hours. 3. In immunohistochemical study, amylase reaction was showed partially and irregularly after 3 hours, was getting little milder after 6 hours. And amylase reaction was gradually increased from the time of 12 hours after experiment up to the time of 48 hours after experiment. But after 168 hours, amylase appearance was diminished. According this result, emotional stress can change of salivary gland structure, and amylase secretion, the important digestive enzyme from salivary gland is changed and it is supposed to make digestive disorder and to make halitosis efficiency. So, we need to study about secretion of amylase.

• The Journal of Korean Academy of Prosthodontics
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• v.53 no.3
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• pp.262-275
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• 2015

The treatment of areas demanding esthetic requirements, such as maxillary anterior teeth, should take into account the achievement of a healthy, harmonious to the surrounding tissue, and an attractive smile line. In this case report, smile line, soft tissue and hard tissue morphology, and the anatomy and proportion of the tooth, must be considered. In patients with unesthetic maxillary anterior ratio due to inadequate gingival contour and diastema caused by peg lateralis, it would be challenging to achieve an esthetic restoration by orthodontic treatment alone. In such case, after orthodontic treatment, dento-gingivo-facial compositional diagnosis and analysis, followed by gingivectomy and prosthodontic restoration is needed to improve the interdental mesial/distal, width/length ratio to achieve a satisfactory esthetic result. In addition, when improving the tooth proportion of peg lateralis by prosthodontic treatment, Porcelain laminate veneer (PLV), which results in less tooth structure loss, reproduction of similar shade to that of the proximal tooth and high transparency, is recommended. This case report demonstrates esthetic improvements by prosthodontic restoration through systematic diagnosis and treatment procedure in patients with unesthetic maxillary anterior proportion after orthodontic treatment due to peg lateralis by means of two female patients aged twenty years old.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.2
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• pp.153-158
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• 2004

Preformed stainless steel crown is an useful restorative material for the treatment of badly broken down primary teeth. However iatrogenic damage to adjacent teeth might occur during the process of tooth reduction. Such damages might lead to plaque accumulation and increase the risks of caries initiation. Especially the damage can make a problem in the first permanent molar. Purpose of this study was to investigate an iatrogenic damage to the first permanent molar during preparation of second primary molar for preformed stainless steel crown. Twelve children restored with preformed stainless steel crown to second primary molar were selected. Contact areas were separated with separation elastics, and tooth surfaces were cleaned. After taking negative impression using vinylpolysiloxane impression material, the specimens were examined by scanning electron microscope for the detection of iatrogenic damage. The prevalence of iatrogenic damage was 66.7% and variable appearances and So we can suggest that when preparing teeth for preformed stainless steel crown, we should be careful about adjacent teeth not to make an iatrogenic damage.

• Journal of the korean academy of Pediatric Dentistry
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• v.40 no.1
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• pp.48-52
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• 2013

Ectopic eruption of the first permanent molar is an abnormal positioning of this tooth, causing a premature resorption of the distal surface of the second primary molar. It occurs in approximately 3~4% of the population and the maxillary arch is usually affected. While 66% of ectopically erupting permanent molars are corrected spontaneously without treatment (i.e. a reversible type), active treatment is necessary for irreversible ectopic eruption cases. The treatment modalities have been divided into two categories: interproximal wedging and distal tipping. Interproximal wedging is indicated for minimal impaction and when the impaction is severe, distal tipping techniques are required. Although much has been written about treatment modalities on unilateral ectopic eruption of the first permanent molar, few reports mention bilateral ectopic eruption cases. In this report, two cases of bilateral ectopic eruption of the first permanent molars in young patients are presented. We describe the use of a modified bilateral Halterman appliance for correction of these cases and the clinical results were satisfactory.

• Restorative Dentistry and Endodontics
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• v.26 no.5
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• pp.363-371
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• 2001

심미성 수복재 중합시 사용되는 광원은 다양한 요인들에 의해 선택되어지고 있지만 이러한 요인들은 앞으로도 논란의 여지를 많이 남겨두고 있다. 또한 현재 사용되고 있는 중합법들이 제각기 독특한 장점들을 갖고 있기 때문에 최적의 중합법 결정이 필요한 시점이다. 이에 본 연구에서는 중합광의 강도(50, 100, 200, 300, 400, 600mW/$\textrm{cm}^2$)와 중합시간(10, 20, 40초)을 다양하게 변화시켰을 때 복합레진의 미세경도와 미세누출도가 어떠한 양태를 보이는지를 관찰하고자 하였다. 본 실험에서는 A3 색상의 혼합형 복합레진인 국산 DenFil과 미세입자형 복합레진인 Esthet X를 사용하였다. 중합 1일 후 복합레진의 Vickers 경도는 다이아몬드형 압흔 길이를 측정하여 평가하였으며 미세누출도는 1% methylene blue용액을 이용한 방법과 주사전자 현미경을 이용한 수복물과 치질간의 최대 이개도 평가법의 두 가지 방법으로 측정하였다. 본 연구의 결과는 다음과 같다; 1. 미세경도는 시편 상면이 하면에 비해 단단한 양태를 보였으며 상, 하면에 관계없이 혼합형 복합레진인 국산 DenFil이 미세입자형 복합레진인 Esthetx에 비해 높은 경도치를 보였다. 2. 모든 미세 경도 실험에서 너무 낮은 광도(50mW/$\textrm{cm}^2$, 100mW/$\textrm{cm}^2$)로 중합한 군에서는 대조군에 비해 유의하게 낮은 미세 경도를 보였다(p<0.05). 3. 상면의 경우, DenFil은 중합시간과 관계없이 200mW/$\textrm{cm}^2$ 이상의 광도에서 대조군(600mW/$\textrm{cm}^2$ 광도로 40초간 중합)과 유의차 없는 미세경도치를 보였으나, Esthet X는 200mW/$\textrm{cm}^2$ 이상의 광도로 40초 동안 중합한 군에서만 대조군과 유의차 없는 미세경도치를 보였다. 4. 하면의 경우 DenFil은 300mW/$\textrm{cm}^2$ 이상의 광도로, Esthet X는 200mW/$\textrm{cm}^2$ 이상의 광도로 각기 40초 동안 중합한 군에서만 대조군과 유의차 없는 미세경도치를 보였다. 5. 법랑질 변연부에서는 색소 침투가 전혀 없었으나 상아질 변연부에서는 정도의 차이는 있었지만 모든 시편에서 색소 침투를 보였다. 6. 통계적 유의차는 없었지만 저광도에서 우수한 미세누출도를 보였으며 색소 침투법과 최대 이개도 평가법간에는 상관성이 매우 낮았다 (p=0.801).

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.1
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• pp.17-31
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• 2018

Purpose: The purpose of this study was to investigate the accuracy of the interocclusal relationship between upper and lower teeth according to the buccal interocclusal record scan using various intraoral scanner systems. Materials and Methods: The upper and lower full arch Models with normal occlusion were scanned with 5 intraoral scanners (Cerec Omnicam, CS3500, iTero, Trios, True Definition). Buccal interocclusal record scan was taken only at the left side while occlusion was intentionally raised by 1 mm, 2 mm, 3 mm, and 4 mm with metal cylinder core embedded within polyvinylsiloxane bite registration material at the right molar region. The superimposition analysis was done to evaluate overall three-dimensional deviation and cross-section analysis was done to evaluate the degree and the direction of deviation of interocclusal relationship. Results: From the superimposition study, Cerec Omnicam showed the least deviation ($165.5{\mu}m$) and CS3500 ($369.0{\mu}m$) showed the largest (P < 0.01). And the deviation was greater in 3, 4, 2 mm group than 1 mm (P < 0.01). From the cross-section study, Cerec Omnicam showed the farthest deviation ($-242.8{\mu}m$) and CS3500 showed the closest deviation ($312.5{\mu}m$) and a significantly high value was shown in 3 mm group. Conclusion: Every intraoral scanner has different accuracy in reproducing interocclusal relationship.

• Archives of Reconstructive Microsurgery
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• v.5 no.1
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• pp.56-61
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• 1996

The nasal ala and columella represent a difficult location for reconstruction, especially when defect area is covered with scar. Local flap, such as forehead flap or nasolabial flap, may result in additional facial scarring and bulkiness that require multiple thinning revisions. Recent delineation of vascular territories of the ear has allowed the use of vascularized auricular free flap in the reconstruction of large ala and columella defects. Authors reconstructed two cases of full thickiness defect of the ala and columella with auricular free flap. The pedicle of this flap is the superficial temporal artery and vein. The donor vessels were anastomosed to the facial artery and vein. The results were satisfactory cosmetically and functionally.