• The korean journal of orthodontics
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• v.39 no.3
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• pp.146-158
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• 2009

Objective: The purpose of this study was to reveal the position of the incisive foramen in relation to the incisive papilla and cusp tips. Methods: Plaster models and CT images of 25 adult orthodontic patients were used to measure the width of the incisive canal and positions of the anterior and posterior borders of the incisive foramen in relation to the incisive papilla. Results: The palatal surface distance from the interdental papilla between the maxillary central incisors to the posterior border of the incisive foramen along the palatal surface was 1.7 fold of the distance from the interdental papilla between the central incisors to the posterior border of the incisive papilla. The distance between the posterior border of the incisive papilla and posterior border of the incisive foramen along the palatal surface was 6.15 ${\pm}$ 1.75 mm. The anteroposterior position of the posterior border of the incisive foramen was slightly anterior to the lingual cusp tips of the maxillary 1st premolars. The width of the incisive foramen was 4.03 ${\pm}$ 0.64 mm, therefore it is recommended to position the mini-implant more than 3 mm laterally when placing a mini-implant lateral to the incisive foramen, from the center. Conclusions: These results can be used as a reference in presuming the position of the incisive foramen when placing mini-implant in the anterior palate area.

• 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.

• Journal of Dental Rehabilitation and Applied Science
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• v.35 no.3
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• pp.153-159
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• 2019

Purpose: Aims to analyze the occlusal wear patterns in maxillary posterior teeth with palatal side abfractions and study the association between occlusal force and abfractions. Materials and Methods: This study was conducted in a total of 308 teeth from 148 patients with palatal side abfractions in maxillary posterior teeth. The occlusal wears in maxillary premolars and molars with palatal side abfractions were classified and recorded. The classification was done by type of teeth, age, and gender, and in order to evaluate the statistical significance between groups, chi-square test was conducted (${\alpha}=0.05$). Results: Palatal side abfractions in maxillary posterior teeth were observed at the highest frequency in the 1st molars, and in all teeth with palatal side abfractions, more than one occlusal wear was observed. In classification by type of teeth, by age, and by gender, the occlusal wears in teeth with palatal side abfractions were observed at high frequency in cuspal inclined plane, central fossa, and marginal ridge, and there was a statistical significance (P < 0.05). Conclusion: Palatal side abfractions were observed at the highest frequency in maxillary 1st molars, and in all maxillary posterior teeth where palatal side abfractions were found, the occlusal wears were observed. And the occlusal wears were observed at high frequency in cuspal inclined plane, central fossa and marginal ridge. Such results show that abfraction is associated with occlusal force.

• Journal of the korean academy of Pediatric Dentistry
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• v.49 no.4
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• pp.402-413
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• 2022

The aim of this study was to identify factors that affect the treatment duration and to predict the duration of forced eruption in impacted maxillary canines using panoramic radiographs and cone-beam computed tomography. This retrospective study was performed by reviewing medical records and radiographs of 73 patients (93 impacted maxillary canines) from the age of 8 to 18 years who were treated with surgical and orthodontic interventions on impacted maxillary canines from January 2012 to December 2020 in Ajou University Dental Hospital. Stepwise multiple regression analysis showed that the distance between the canine cusp tip and the occlusal plane, mesio-distal location, bucco-palatal location, patient's age, and use of rapid palatal expansion are significant factors with regard to the duration of forced eruption. There was a statistically significant correlation of the treatment duration with the angulation between the axis of the canine and the occlusal plane and unilateral or bilateral impaction. It can be concluded that the duration of forced eruption in impacted maxillary canines could be shorter when the impacted canine is closer to the occlusal plane and located in the lateral incisor or canine area, buccal or middle, the patient is younger and uses rapid palatal expansion.

• 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.

• Restorative Dentistry and Endodontics
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• v.29 no.4
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• pp.346-352
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• 2004

The purpose of present study was to evaluate the polymerization shrinkage stress and cuspal deflection in maxillary premolars resulting from polymerization shrinkage of composites and compomers. Composites and compomers which were used in this study were as follows: Dyract AP, Z100, Surefil. Pyramid, Synergy Compact, Heliomolar, Heliomolar HB, and Compoglass F. For measuring of polymerization shrinkage stress, Stress measuring machine (R&B, Daejon, Korea) was used. One-way ANOVA analysis with Duncan's multiple comparison test were used to determine significant differences between the materials. For measuring of cuspal deflection of tooth, MOD cavities were prepared in 10 extracted maxillary premolars. And reduction of intercuspal distance was measured by strain measuring machine (R&B, Daejon, Korea) One-way ANOVA analysis with Turkey test were used to determine significant differences between the materials. Polymerization shrinkage stress is $\mathbb{\ulcorner}$Heliomolar, Z100, Pyramid < Synergy Compact Compoglass F < Dyract AP < Heliomolr HB, surefil$\mathbb{\lrcorner}$ (P < 0.05). And cuspal delfelction is $\mathbb{\ulcorner}$Z100, Heliomolar, Heliomolar HB, Synergy Compact Surefil. < Compoglass F < Pyramid, Dyract AP$\mathbb{\lrcorner}$ (P < 0.05). Measurements of ploymerization shrinkage stress and those of cuspal deflection of the teeth was different. There is no correlation between polymerization shrinkage stress and cuspal deflection of the teeth(p > 0.05).

• The Journal of the Korean dental association
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• v.21 no.4 s.167
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• pp.293-297
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• 1983

Bruxism이란, 일반적으로 기능이외의 목적으로 상하악 치아를 악물거나 갈음질 하는 것이라고 정의된다. 동일한 상태를 서술하는 용어로 neuralgia traumatica, Karolyi effect, occlusal habit neurosis, parafunction 등이 있으며, 수면중의 이갈음질을 bruxism, 주간의 습관성 이갈음질을 bruxomania로 구분하기로 한다. 또한 centric bruxism과 eccentric bruxism으로 분류하기도 한다. eccentric bruxism은 통상적 의미의 수면중의 bruxism이며, 하악의 측방운동중의 이갈음질이고 뽀드득하는 갈음질 소리를 냄, 저작근육의 긴장도가 증가되어 있으면서 등장성수축을 나타내고, 비중심위의(eccentric) 교합간섭이 주요 유발인자인 반면에 centric bruxism은 중심교합위에서 상하악 치아를 간헐적으로 악무는 것(clenching)은 의미하고 - 지속적으로 악무고 있는 것은 clamping이라고 함.- 주로 주간에 행하며 갈음질소리를 들을 수 없고, 역시 저자근육의 긴장도가 증가되어 있으며 등률성수축을 나타내고, 중심교합위에 근접하여 존재하는 교두간섭이 유발인자이다. bruxism이나 clenching과 부정교합의 관계는 bruxism과 clenching은 부정교합을 야기할 수 있고, 부정교합도 역시 bruxism과 clenching을 유발시키는 작용을 할 수 있는 악순환적 관계이다. 현저한 부정교합을 가지고 있는 bruxism환자의 교정치료는 그 목적이 bruxism의 치료라기보다는 오히려 부정교합의 치료이며 부차적으로 bruxism의 치료를 기대하게 된다. 그러나 bruxism이 장기간 지속되어 치아 및 그 주위조직, 악관절과 신경근계에 심한 손상을 주었을때의 교정치료는 일반적으로 제한을 받을 뿐만아니라 bruxism의 처치에는 거의 무의미한 치료가 될 수 있다. 따라서 거자는 bruxism 환자의 교정치료라는 제목의 원고 청탁을 받았으나 편집위원의 양해아래 장치를 이용한 bruxism의 치료에 관하여 서술하려 한다.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.2
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• pp.310-317
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• 2009

Dens evaginatus is a dental anomaly involving an extra cusp or tubercle that protrudes from the occlusal surface of the affected tooth. The prevalence of dens evaginatus is 1 to 4 percent, and dens evaginatus is observed most commonly in premolars. It can be worn or fractured easily, resulting in pulpal exposure, pulpal infection, loss of vitality, facial infection and osteomyelitis. Since the tooth frequently has the immature apex when the tubercle is fractured, there is difficulty in treatment. Although calcium hydroxide is widely used for pulp treatment of an immature permanent tooth, several alternatives have been suggested to reduce patient's appointments. Mineral trioxide aggregate is considered biocom-patible and has excellent marginal sealing ability. In addition, it can minimize patient's visits. In this case report, apexification with MTA was attempted on the immature premolars in patients with cellulitis patient, caused by pulp necrosis due to dens evaginatus. Favorable clinical and radiologic results were achieved. In one case, continued root formation was observed.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.2
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• pp.127-136
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• 2018

The patient who has severely absorbed residual ridges, treatments are challenging to satisfy many factors: support, retention, stability, etc. The neutral zone or monoplane occlusion with non-anatomical tooth would be helpful to get additional retention and stability. The monoplane occlusion has been used long time because it can eliminate horizontal forces and many other advantages. The lingualized occlusion was introduced to improve chewing efficiency and esthetics. But from a stability aspect, it seems controversy between monoplane occlusion and lingualized occlusion. This case report shows the results of the treat two flat residual ridge patients using functional impression; piezography, and made 2 other dentures with monoplane and lingualized occlusion that patient can select denture.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.4
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• pp.563-567
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• 2009

Incontinentia pigmenti(Bloch-Sulzberger syndrome) is a sex-linked hereditary disorder so girls are almost exclusively affected. The frequency rate is approximately 1:40,000 among girls. It is associated with skin, ocular, dental, skeletal and central nervous deformities. We reported 2 cases of medically diagnosed IP patients who were 4 and 5 years old girls. They had thin and sparse hair, and represented congenital missing of multiple primary and permanent teeth, accessory cusps and cone-shaped crowns. Therefore we report the dental manifestations and treatment progress.