• The korean journal of orthodontics
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• v.41 no.4
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• pp.255-267
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• 2011

Objective: The purpose of this study was to confirm the reliability of a cone beam computed tomography (CBCT)-generated panoramic view based on a CBCT 3D image and to find the most helpful 2D panoramic image compared with CBCT 3D image when examining the mesiodistal tooth axis. Methods: A test model was constructed according to cephalometric norms. The test model was repeatedly repositioned for CBCT and panoramic radiographic imaging. Panoramic radiographs were acquired at each of the following 3 occlusal plane positions: $-5^{\circ}$, $0^{\circ}$, and $+5^{\circ}$. Measurements of mesiodistal tooth axis in CBCT 3D image, CBCT-generated panoramic view, and panoramic radiographs were compared. Results: Compared with the CBCT-generated panoramic view, CBCT 3D image showed significant difference in the mesiodistal tooth axis in the premolars and no significant difference in the mesiodistal tooth axis in the incisors and canines. Mesiodistal tooth axis on the CBCT-generated panoramic view was significantly different from that on panoramic radiographs. Conclusions: CBCT-generated panoramic view can be a useful tool for evaluating mesiodistal tooth axis.

• The korean journal of orthodontics
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• v.41 no.4
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• pp.288-296
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• 2011

Objective: The purposes of this study were to evaluate the relationship between the dental and basal arch forms; to analyze their differences in the tapered, ovoid, and square arch forms in normal occlusion by using three-dimensional (3D) virtual models; and to test the hypothesis that the overjet and maxillomandibular basal arch width difference have a significantly positive correlation. Methods: Seventy-seven normal occlusion plaster casts were examined by 3D scanning. Facial axis (FA) and WALA points were digitized using the Rapidform 2006 software. The dimensions of the dental and basal arches and the overjet were measured. The samples were classified into 3 groups according to arch forms: tapered (n = 20), ovoid (n = 20), and square (n = 37). Analysis of variance (ANOVA) was used to compare the dental and basal arch dimensions. The Pearson correlation coefficients between the intercanine as well as the intermolar widths at the FA and WALA points were calculated. Results: With regard to the basal arch dimensions, the tapered arch form showed a larger mandibular intermolar depth than the ovoid. Strong correlations were noted between the basal and dental intermolar widths in both the upper and lower arches (r = 0.83 and 0.85, respectively). Moderate correlation was found between the upper and lower intercanine widths (r = 0.65 and 0.48, respectively). Conclusions: The 3 dental arch form groups differed only in some dimensions of the skeletal arch. Moderate correlations were found between the basal and dental intercanine widths. These findings suggest that the basal arch may not be a principle factor in determining the dental arch form.

• The korean journal of orthodontics
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• v.50 no.5
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• pp.336-345
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• 2020

Objective: To investigate the treatment modalities (Tx-Mods) for patients with unilateral hemifacial microsomia (UHFM) according to Pruzansky-Kaban types and growth stages. Methods: The samples consisted of 82 Korean UHFM patients. Tx-Mods were defined as follows: Tx-Mod-1, growth observation due to mild facial asymmetry; Tx-Mod-2, unilateral functional appliance; Tx-Mod-3, fixed orthodontic treatment; Tx-Mod-4, growth observation due to a definite need for surgical intervention; Tx-Mod-5, unilateral mandibular or bimaxillary distraction osteogenesis (DO); Tx-Mod-6, maxillary fixation using LeFort I osteotomy and mandibular DO/sagittal split ramus osteotomy; Tx-Mod-7, orthognathic surgery; and Tx-Mod-8, costochondral grafting. The type and frequency of Tx-Mod, the number of patients who underwent surgical procedures, and the number of surgeries that each patient underwent, were investigated. Results: The degree of invasiveness and complexity of Tx-Mod increased, with an increase in treatment stage and Pruzansky-Kaban type (initial < final; [I, IIa] < [IIb, III], all p < 0.001). The percentage of patients who underwent surgical procedures increased up to 4.2 times, with an increase in the Pruzansky-Kaban type (I, 24.1%; IIa, 47.1%; IIb, 84.4%; III, 100%; p < 0.001). However, the mean number of surgical procedures that each patient underwent showed a tendency of increase according to the Pruzansky-Kaban types (I, n = 1.1; IIa, n = 1.5; IIb, n = 1.6; III, n = 2.3; p > 0.05). Conclusions: These findings might be used as basic guidelines for successful treatment planning and prognosis prediction in UHFM patients.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.4
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• pp.415-422
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• 2011

The study on correlation between the parents' character of orthodontic patients and patients cooperation. Although dentists have excellent skill and technique, patients' cooperation is always demanded. Patients' poor cooperation results in poor treatment result. Cooperation between psycho-social state of parents and patient's cooperation was studied. The parent's psychosocial state is evaluated with scl-90-r. The cooperation is measured by appointment time compliance, appliance taking rate, breakage of appliance, and fee paying. Parents' psychosocial contents are somatization, obsessive-compulsive, interpersonal sensitivity, depression, anxiety, hostility, phobic-anxiety, paranoid ideation, psychoticism, and additional item. Statistics was done by SPSS WINDOW version 12.0 program. The result showed no correlation between patients' cooperation and their parents' psychosocial state. There is no correlation between father's psychosocial state and patients' cooperation except psychoticism. There is no correlation between mother's psychosocial state and patients' cooperation. However, there was correlation among cooperation variables: appointment time compliance, appliance taking rate, breakage of appliance, cost paying. Appliance taking rate and cost paying showed positive correlation. Our findings suggest that patients' cooperation does not followed their parents' pychosocial state. Other combined factors should be considered like pychosocial state of patient and doctor-patient relationship.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.3
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• pp.548-555
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• 2008

Dentigerous cyst is the most common type of odontogenic cyst followed by radicular cyst. Most of dentigerous cysts originate from the permanent dentition and a few of them are associated with mesiodens. The complications of a dentigerous cyst associated with mesiodens are eruption abnomalies of adjacent teeth, root resorption, displacement, rotation, diastema and the secondary infection of the cyst due to adjacent teeth. The treatment of a dentigerous cyst of a maxillary mesiodens is to enucleate a cyst with a mesiodens. Otherwise, when it is close to adjacent teeth, a cyst is to reduce the through marsupialization after removing a mesiodens. There are numerous studies on dentigerous cysts and mesiodentes alone; however, the studies on the association of the two are rare. These are case reports about patients with mixed dentition whose dentigerous cyst of a maxillary mesiodens had been removed. After removal, the patients have been regularly checked up and shown satisfactory progress.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.3
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• pp.516-522
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• 2008

In the case of the impacted teeth, the clinician has to consider development of tooth, site of impaction, eruption path, and cooperation of patient. If there are genetic or general factors to effect the eruption of tooth, the clinician treats these first and then takes the early treatment for eruption guidance. If there are physical factors to intercept eruption, the clinician put them off first. However, if there are no factors to effect eruption of tooth and enough space for eruption, the clinician can consider extraction of deciduous teeth, forced eruption and surgical reposition. In case of surgical repositioning, proper time for root development, proper socket formation, and minimal trauma are important for success. This case presents displaced impacted maxillary central incisor with dilacerated root. The development of root is Nolla's stage 7, and the tooth was treated by surgical repositioning. We can observe no root resorption and good healing pattern.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.2
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• pp.344-350
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• 2000

Incidence of crown-root fracture due to traumatic injury, have been reported 3% in the permanent dentiton, 2% in the deciduous dentition. There are two treatment methods for crown-root fractured teeth with pulp exposure, when the fracture line was located under the alveolar crest. One way is the extrusion by orthodontic force the other way is intra-alveolar transplantation which occlusally repositioning of apical fragment in the alveolar socket. Since intra-alveolar transplantation has introduced in 1970s, it was practiced as alternative to orthodontic extrusion. As the result, this method may thoughted that had a good prognosis. As a result of trauma, completely crown-root fracture was occured in the maxillary right central incisor in this case. We couldn't reposition the deepest fracture line above the alveolar crest by the conventional surgical extrusion, because apical fragment was too short. Thus, after extraction of apical fragment, we repositioned it to the socket following demineralized freezed dried bone graft, which possible to support the apical fragment. At the 15-month recall examination, the root still showed normal mobility and there was not observed any in flammatory or replacement root resorption in the periapical radiograph.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.3
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• pp.534-547
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• 2006

Ectopic eruption and impaction of canines is a frequently encountered clinical problems. The incidence of impaction ranges between 1-3%. The cause of canine impaction can be the result of localized factors or can be a polygenic multifactorial inheritance and associated with other dental anomalies. The general dentist and pediatric dentist should know how to properly diagnose and manage potential disturbances in the eruption of maxillary canine. Diagnosis of impacted canine at age 8-10 years can significantly reduce serious ramifications, including surgical exposure and orthodontic traction as well as root resorption of the lateral incisors. Extraction of primary canine would be one of the method to prevent the impaction. The surgical procedure should be designed to minimize the destruction of periodontal tissue of impacted canine. Closed eruption technique is thought to be optimal method of surgical exposure compared with other methods. An overview of the incidence, sequela as well as the surgical periodontal, and orthodontic consideration in the management of impacted canine was presented.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.2
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• pp.326-333
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• 2003

The appropriate treatment for eruption guide of impacted teeth necessitates the formulation of a comprehensive treatment plan, which is dependent upon a number of factors such as the condition of the deciduous teeth, dental and skeletal relationship, dental age of the patient, willingness of the patient to undergo extensive dental treatment and financial considerations. If the etiology of the eruption disturbance has been identified, the elimination of the causes and various procedures can be used for eruption guide. Particularly the transplantation is a valuable alternative to extraction of impacted teeth, where surgical exposure and subsequent orthodontic realignment are difficult or impossible. This report present three cases of autotransplantation of impacted maxillary canine. As the result in these cases, atraumatic removal of donor tooth during operation is prerequisite to an optimal clinical result. Due to a high possibility of pulp necrosis, endodontic treatment of fully developed transplanted teeth should be undertaken. In complex case, autotransplantation can save time and less expensive than orthodontic forced eruption. Recipient socket should be prepared to a size that is slightly larger than the root of the donor tooth, and can be prepared with open or close procedure depends on root size of donor tooth and buccolingual width at transplantion site.

• Journal of the korean academy of Pediatric Dentistry
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• v.39 no.4
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• pp.357-365
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• 2012

There are orthodontic treatment which involves tooth movements and orthopedic treatment which involves skeletal movement. In childhood and adolescence, especially for the treatment of orthopedic treatment, the evaluation of bone maturity and growth potential is very important. The purpose of this study is to assess the developmental stage and to compare the amount of mandibular growth with cephalometric radiographs and hand-wrist radiograph in 6 to 13-year-old children with normal occlusion. The results are as follows : SMI and CVM showed a significant correlation (p < 0.05). Ar-Go, Co-Go, N-Go, S-Gn, N-Me, Co-Gn, Go-Me, Go-Gn increased with increasing maturity of hand-wrist and Ar-Go, Co-Go, N-Go, S-Gn, N-Me, Co-Gn, Go-Me, Go-Gn increased with increasing maturity of cervical vertebrae maturation. Also Ar-Go, Co-Go, N-Go, S-Gn, N-Me, Co-Gn, Go-Me, Go-Gn showed a significant correlation with each of the cervical vertebrae maturation stages and hand-wrist maturation stages (p < 0.05). These results suggested that mandibular growth had a significant correlation with cervical vertebrae maturation stages and hand-wrist maturation stages.