• The korean journal of orthodontics
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• v.24 no.3 s.46
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• pp.631-648
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• 1994

The purpose of this study was to investigate the effects of different types of orthodontic force on the root resorption and repair in rat molar. 77 rats were divided into three groups; The control group was not equiped with orthodontic appliance between incisor and first molar. The experimental group was subdivided into closed coil spring subgroup and elastic chain subgroup by the application methods of orthodontic force. Initial orthodontic force between incisor and first molar was 100g. Experimental period was 8 weeks; for 4 weeks the appliance was acting and for another 4 weeks, removed. Root resorption and repair in the root of first molar was examined by light microscope for histologic changes and by inductively coupled plasma spectroscopy(ICP) for quantitative changes. The results were as follows: 1. In the closed coil spring subgroup odontoclasts and root resolution were appeared one week earlier. 2. One week after orthodontic force was eliminated the repair response in the resorptive lacuna was seen in both subgroups. Delayed resorption was seen on the periphery of resorptive lacunae whereas reparative response was seen in the center of lacunae. A new resorption was seen one week after orthodontic force was eliminated. Root contour was partially restored by repairing of resorbed root. 3. The weight ratios of calcium and phosphorous to the sample were decreased during resorptive process but increased during repair process in both the orthodontic groups, but not more than the control group. 4. By different types of orthodontic force (closed coil spring or elastic chain) resorption process was affected but repair process was not.

• Journal of Periodontal and Implant Science
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• v.38 no.4
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• pp.603-610
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• 2008

Purpose: The guided bone regeneration (GBR) technique is widely used in periradicular surgery. However, there is still some controversy regarding the effectiveness of GBR in promoting bone healing after periradicular surgery. The purpose of this study was to evaluate the resorbable membrane on the osteointegration of immediate implants in sites with periradicular lesion that had been removed by periradicular surgery. Materials and methods: Six roots of lower second premolars and 15 roots of lower third and fourth premolars of dogs were used as control and experimental teeth, respectively. Periradicular lesions were induced only in the experimental teeth. Twelve weeks later, the control and experimental teeth were extracted and implants were placed immediately. Periradicular lesions were removed with osteotomy, curettage and saline irrigation. Resorbable membranes were used in experimental group 1 but not in experimental group 2. After 12 week of healing period, the implants were clinically not mobile and showed no signs of infection. Data obtained by histomorphometric analysis were analyzed by Kruskal-Wallis test. Results: The control group showed a significantly higher bone to implant contact (BIC) ($74.14{\pm}16.18$) than experimental group 1 ($40.28{\pm}15.96$) and 2 ($48.70{\pm}17.75$)(p<0.05). However, there was no significant difference between experimental group 1 and 2. Conclusion: Although BIC in experimental groups were lower than in control group, immediate implant can be successfully placed at extraction socket with periradicular lesion and osseous defect. However, the use of resorbable membrane in bony defect created during periradicular surgery was questioned.

• Journal of the korean academy of Pediatric Dentistry
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• v.42 no.1
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• pp.87-101
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• 2015

The premature loss of the mandibular primary canine is relatively frequent and a sign of the upcoming space problems in the transitional period. This situation is caused by the permanent lateral incisor resorbing the root of the primary canine during its eruption. Bilateral loss of primary canines in a crowded arch leads to the lingual tipping of the permanent incisors, with the consequent reduction in the arch perimeter and increase in overbite. When the loss of a primary canine is unilateral, tipping of the adjacent incisors occurs toward the space, resulting in midline deviation. In these situations, treatment possibilities, such as extraction of the antimeric tooth or placement of a passive lingual arch, can be applied; although there are some controversies concerning this. Most space problems with less than 4 mm can be resolved through preservation of the leeway space using sequential disking of the primary teeth and a passive lingual arch, regaining space or limited arch expansion in the late mixed dentition. In cases with 4~6 mm of space problems, arch expansion (A-P or transverse) can be applied. Space problems with more than 6 mm should be treated through diagnosis and treatment planning. Most of these cases will require extraction of permanent teeth including serial extraction (guidance of eruption).

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.3
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• pp.519-525
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• 2007

Supernumerary tooth is developed from overgrowth of dental laminar and is mainly observed in the maxillary anterior area, named 'mesiodens. Mesiodens cause many problems such as malposition of permanent anterior tooth, diastema, formation of cyst, and eruption to oral or nasal cavity. Extraction, therefore, is generally recommended choice of treatment. This case report describes that the patient is a 9 years and 8 months old boy, whose unilateral maxillary incisor was missing due to trauma, and he had a mesiodens. We practiced autotransplantation of the mesiodens to the missing maxillary central incisor area and then restored with prosthetics, substantially kept out alveolar bony resorption and provided esthetic appearance. Mesiodens was too small to be used as an abutment because its length is totally 14mm, so that poor prognosis was anticipated due to bad crown/root ratio. However, we observed clinically acceptable result during the observation period of 8 months after operation.

• The Journal of Korean Academy of Prosthodontics
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• v.55 no.4
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• pp.403-409
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• 2017

In the case of an extraction in the maxillary anterior region, immediate placement of implant-supported fixed prosthesis can be considered as a treatment option. Fewer surgical operations, reduced treatment time, and optimal availability of existing bone are obvious advantages of the method; however, when applied in the continuous maxillary anterior region, inter-implant distance must be carefully considered, as well as accurate diagnosis and treatment planning for predictable outcome. In this case report, immediate placement of two implants in the continuous maxillary anterior along with bone graft following the extraction of root rests, and the restoration of provisional and implant-supported fixed prosthesis on a 63-year-old patient had resulted in both esthetically and functionally satisfactory clinical outcomes.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.2
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• pp.177-184
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• 1991

A giant cell granuloma and a cementifying fibroma occurring in the same lesion of right mandibular body in a 10 year old boy is presented with a 12 month follow up without recurrence or any other complications after operation. The relatively small lesion of cementifying fibroma was well delineated from the larger lesion of central giant cell granuloma, and as their origins are different each other(odontogenic or connective tissue origin), we have considered that both lesions had developed independently. Clinically, the evidencesa of aggressiveness of giant cell granuloma were also found, that is, large size, earlier age of 10, root resorption of lower right 1st annd 2nd molars and cortical perforation. With curettage and electric cauterization, we have treated both lesions satisfactorily.

• The korean journal of orthodontics
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• v.28 no.3 s.68
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• pp.479-486
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• 1998

Bimaxillary Protrusion can be treated effectively in growing patients and in adults with conventional orthodontic therapy. However, In the adult patient, combined surgical and orthodontic treatment modalities may offer distinct advantages over such conventional therapy. In those cases complicate by vertical jaw dysplasia, sagittal dysplasia, or transverse skeletal discrepancy in addition to bimaxillary protrusion, the possibilities of obtaining successful results through orthodontic treatment alone greatly diminish. Surgical retraction of both maxillary and mandibular anterior segments with subapical osteotomies and ostectomies in the extraction site may be a good treatment alternative. Treatment time and possible adverse effects of lengthy orthodontic therapy may be reduced and optimum esthetic improvement may be facilitated. On the following cases, patient who had bimaxillary protrusion with Angle class III malocclusion was treated with combined orthodontic - surgical therapy by anterior subapical segmental osteotomies.

• The Journal of Korean Academy of Prosthodontics
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• v.39 no.4
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• pp.376-390
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• 2001

Alveolar bone changes after immediate loading on implants up to one year were observed by means of standard intraoral X-ray measurement which were taken at 3 month intervals. At the same time, bone density changes were observed according to digital subtraction method which is a becoming a more and more promising diagnostic tool for implants. Following results were obtained ; 1. There was no significant difference in the amount of alveolar bone loss implant type, sex and implant diameter, but there was difference according to case selection. In fully bone anchored prostheses cases, bone loss was $1.16{\pm}0.15m$ whereas, in partial edentulous cases, it was $1.84{\pm}0.08mm$. 2. Alveolar bone loss after immediate loading showed a higher degree of bone loss than after submerged loading in the initial three months. But there were no significant difference at the 12th month. 3. According to the one year bone density change observation at the alveolar bone surrounding the implant, significant change was observed vertically, whereas no significant change could observed horizontally. According to the above mentioned results, we can conclude that immediate loading of implants results in a higher degree of alveolar bone loss in one year than submerged loading. But since alveolar bone loss rate decreases to a reasonable rate after the initial 3 months of rapid bone loss, immediate loading of implants seems to be an acceptable treatment modality for patients with good bone conditions. Fully bone anchored cases showed an favorable outcome, but partial edentulous cases showed more bony resorption. So this cases considered in case selections. Bone density changes observation in the study was performed for only one year therefore a more longitudinal observation may be studied.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.3
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• pp.317-326
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• 2017

The aim of this study was to investigate the survival and success rates of autotransplanted maxillary canine at the artificially formed recipient socket and evaluate the factors that influence survival and success rates. A total of 28 children who had 37 impacted canines were reviewed over the mean observation time of 25.1 months. Tooth mobility, pathologic root resorption, vertical bone loss, periapical lesion and anklyosis of donor tooth were investigated clinically and radiographically. The survival rate was 100%. The success rate was 64.9%, because 13 teeth were evaluated as unsuccessful. Significant parameter in determining the success rate of autotransplantation was enlarged follicle size of donor tooth according to Cox proportional hazard regression model. The results provide information necessary for clinician to make a better treatment decision about autotransplantation at the artificially formed recipient socket.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.3
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• pp.529-533
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• 2006

Supernumerary teeth are defined as an excess in the number of teeth when compared to the normal dental formula. They are more prevalent in the permanent dentition than the primary dentition. Supernumerary teeth can occur in the maxilla, mandible, or both. But the majority are found in the maxilla and most of it is found in the premaxilla region The present cases documents about the uncommon cases of supernumarary teeth on maxillarty premolar area and mandibular incisal area.