• Journal of Periodontal and Implant Science
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• v.32 no.3
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• pp.643-653
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• 2002

Periodontal supporting tissue goes through destruction by chronic inflammatory periodontal disease as two aspect. One is qualitive aspect such as alteration of periodontium, the other is quantitative aspect such as alveolar bone loss. According to many authors, PDL is responsible for biting force, and there are two mean. for measuring PDL's function - mobility test and biting force test. This study was conducted to compare the biting force with remaining bone level, that is, quantitative aspect of periodontium, in anterior and premolar teeth at periodontal maintenance phase. 17 patients on periodontal maintenance phase during 6 months at minimum were selected for this study. For the same condition, 4 anterior, canine, premolar teeth were tested by MPM-3000 bite-force register at the same time(a.m.l0-12), the same position, the same posture, by the same examiner. Patients of TMI), ill-fitting pros thesis, general disease, malocclusion and the teeth of TFO, absence of opposing teeth, malposition were excluded. Remaining bone level was measured on the panorama X-ray film through 5 level from 1mm below CEJ to root apex. Teeth were examined twice, and bigger one was selected. If the values showed large difference. examinatin was re-done and the mean was selected. The results were as follows ; 1. In the 4 anterior group, as the remaining bone is decreased, the average of maximal biting force is decreased. Especially, at 3/5 bone level, maximal biting force is decreased significantly(p<0.01). 2. In the canine group, as the remaining bone is decreased, the average of maximal biting force is decreased. Especially, at 2/5 bone level, maximal biting force is decreased significantly(p<0.01). 3. In the premolar group, as the remaining bone is decreased, the average of maximal biting force is decreased. Especially, at 3/5 bone level, maximal biting force is decreased significantly(p<0.05). From the results of this study, clinicians could utilize these efficiently when they have to determine the proper restorative materials, time for tooth extraction, treatment plan, prognosis.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.4
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• pp.644-648
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• 2005

Supernumerary tooth was resulted from excessive proliferation of dental lamina and associated with familial tendency and a congenital syndrome such as Cleidocranial dysostosis or Gardner's syndrome. Incidence reports identify a range of $0.3{\sim}0.8%$ in primary dentition, $1.0{\sim}3.5%$ in permanent dentition with males being affected twice as frequently as females, maxilla nine times as frequently as mandible. The most common supernumerary tooth is the mesiodens, which located between the maxillary central incisors, and the next common site is the fourth molar and lateral incisors. Supernumerary teeth are uncommon in the mandible, but premolars are the most common supernumerary teeth and occurrence is very rare in the incisor region of the mandible and the incidence is 2%. We need a early diagnosis and appropriate treatment plan because of possiblilty of diastema and eruption failure displacement, rotation of the associated permanent teeth, root resorption and dentigerous cyst with presence of the supernumerary teeth. In this two case, one supernumerary tooth located in the mandibular incisor region, the other supernumerary tooth located in premolar region. We could get normal alignment of mandibular dentition by extraction and orthodontic treatment.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.2
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• pp.217-223
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• 2005

The term 'impaction teeth' is used to designate a tooth which remains unerupted in jaw beyond the time at which it should normally be erupted. Most cases of impacted teeth reported in the literature are permanent teeth. The impaction of primary teeth occur rarely whereas impaction of second primary molars is more numerous than all other impactions. Failure of eruption of primary teeth may cause a number of complications, such as interference with development and eruption of successive permanent teeth, malocclusion, cystic change of tooth follicle. The clinican should consider the various treatment option available (a) No treatment and observation, (b) surgical extraction (c) space regainer. Proper treatment plan should be established after thought consideration of impacted tooth and it's relation with successive permanent tooth.

• The korean journal of orthodontics
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• v.20 no.3 s.32
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• pp.447-462
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• 1990

The objective of this experiment is to observe structural differences in the othodontic movement of vital (control group) and devitalized (experimental group) teeth in the mongrel dogs. The 5 utilized dogs in this experiment were approximately 1 year of age and their average weight was about 12 Kg. Endodontic therapy was performed on the 2nd premolars in upper & lower jaws of each animal under the general anesthesia by intravascular injection of 25mg/kg of pentobarbital sodium. The canals of the teeth were obturated by using gutta percha in conjunction with root canal sealer (AH26 Densply). One of the roots in the 2nd premolars was hemisected to make an extraction space for the devitalized teeth to be moved. The edgewise technique was employed for the movement of the teeth. Orthodontic models and intraoral roentgenograms were taken before and after orthodontic tooth movement. The open coil springs (.010 x .040) were used at interbraket space in order to provide equal forces (75gm) between the teeth in each arch wire. After 13 weeks of active orthodontic tooth movement, dogs were sacrified and the experimental results w ere examined through the intraoral radiography, microscopic examination and scanning electromicroscopic examination at the root sulfate. From the results of the study, the following conclusions may be drawn: The root resolution and cemental deposition were observed within the pressure and tension site in both group. 2. The root resorbed lacunae were observed in the cementum and/or into the dentin in both group. 3. The prominent osteoblastic activities were observed on the alveolar margin in the tension site in both group. 4. A few of blood vessels were observed in the pressure site, but also lots of blood vessels were observed in the tension site especially in the periphery of the alveolar bone in both group. 5. In the pressure site, resorbed lacunae were formed with deep and narrow cavity in the control group; the shallow and wide cavity in the experimental group. 6. In the pressure site, the repaired cementum or cementoid tissue was lined on cementum in the experimental group, but not in the control group. 7. There was no significant difference between external root resolution of endodontically and vital teeth when both were subjected to orthodontic forces.

• Journal of Periodontal and Implant Science
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• v.23 no.2
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• pp.261-281
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• 1993

The author transplanted periodontally-diseased teeth which had been treated with citric acid into a clinically healthy extraction sockets and periodontally-affected extraction sockets, and compared with the healing processes within these tissues. Recipient sites were prepared by surgically removing a part of alveolar bone of premolars of adults dogs, placing elastic orthodontic ligatures for 8weeks, thereby inducing periodontal disease. The diseased roots were extracted and transplanted into healthy extraction sockets, and these were designated as control group 1. Diseased roots transplanted into diseased sockets were designated as control group 2. Diseased roots which had been root planed, treated with citric acid and transplanted into healthy sockets were designated as experimental group 1, while identically treated roots which had been transplanted into diseased sockets were designated as experimental group 2. Observations were made at weeks 2, 8 and 12, with following results. 1. At week 2, experimental group 2 showed some inflammatory cell infiltration in the connective tissue above the extraction sockets, while control groups showed less inflammatory or foreign body reactions throughout the experiment. 2. In both control groups, root surface resorption was observed throughout the experiment, while experimental groups showed a little resorption. 3. Control group 1 & 2 showed ankylosis by newly-formed bone ground the resorbed root surfaces, while experimental group 1 & 2 displayed collagen fibers which are not functionally-arranged, with random, loose arrangement or parallel orientation to root surfaces, and newly-formed bone outside of them. 4. In both control groups & experimental groups which had been transplanted into a clinically healthy extraction sockets & periodontally affected extraction sockets groups, histological differences were not significant. 5. Root resorption or ankylosis in control group 1 & 2 had increased quantitatively as experiment progressed. 6. New bone formation developed from the base and lateral wall of extraction sockets. In both control groups & experimental groups, root surfaces lying next to the upper portion of extraction sockets showed little alveolar bone formation and surrounded by connective tissue fiber at weeks 2 & 8, while at weeks 12, they did show alveolar bone formation. 7. At week 12, experimental group 2 showed numerous cells which appeared to be periodontal ligament cells, with functionally arranged connective tissue fibers between the roots and alveolar bone.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.3
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• pp.217-225
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• 2001

Any fracture passing through the socket of a teeth is compounded intraorally, even if the fracture is not displaced and the tooth is firm in its socket. Before the advent of antibiotic therapy the danger of infection in a compounded fracture posed severe problems in treatment. Infection is reduced by antibiotic therapy but prolonged use of antibiotics is not justified in an attempt to save a tooth which might eventually be sacrificed. There is still controversy in the management of third molar in mandibualr angle fracture, particulary in regard to their retention or removal at the time of fracture treatment. So we surveyed the 159 patients who were treated with open reduction of mandibular angle fracture containing third molar in fracture line, and compared with the postoperative infection rate depending on time intervals between injury and operation, eruption state of third molar, non-extraction or extraction of third molar related to eruption state, non-extraction or extraction of third molar related to condiition of third molar and its surrounding periodontium and were to propose treatment guidline of third molar in mandibular angle fracture The results obtained were as follows : 1. There were no statistical significance between the time from injury to operation and postoperative infection. 2. There were no statistical significance between eruption state of third molar and postoperative infection. 3. In case of retention of the third molar, there were no statistical significance between eruption state of third molar and postoperative infection, but in case of extraction, postoperative infection was high rate in complete impacted cases. 4. There were no statistical significance between non-extraction or extraction of third molar and postoperative infection depending on condition of third molar. There are no difference in infection rate statistically according to the time from injury to operation, eruption state and condition of third molar, but retention of third molar revealed lowered infection rate in completely impacted cases. By terms of the manegement of third molar, we should extract or preserve third molar in the line of the mandibular angle fracture according to possibility of infection.

• Imaging Science in Dentistry
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• v.46 no.3
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• pp.223-227
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• 2016

A static, unilateral, and focal bone depression located lingually within the ascending ramus, identical to the Stafne's bone cavity of the angle of the mandible, is being reported. During development of the mandible, submandibular gland inclusion may lead to the formation of a lingual concavity, which could contain fatty tissue, blood vessels, or soft tissue. However, similar occurrences in the ascending ramus at the level of the parotid gland are extremely rare. Similar cases were previously reported in dry, excavated mandibles, and 3 cases were reported in living patients. A 52-year-old African American male patient was seen for pain in the mandibular teeth. Panoramic radiography showed an unusual concavity within the left ascending ramus. Cone-beam computed tomography confirmed this incidental finding. The patient was cleared for the extraction of non-restorable teeth and scheduled for annual follow-up.

• The Journal of Korean Academy of Prosthodontics
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• v.39 no.6
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• pp.633-640
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• 2001

Statement of problem. Relatively low success rate of root analogue implant system was supposed to be due to the time duration between extraction and implant installation. The use of three-dimensional computer tomography and the reconstruction of objects using rapid prototyping methods would be helpful to shorten this time. Purpose. This aim of this study was to evaluate the application possibility of the 3-dimensional computer tomography and the rapid prototyping to root analogue implants. Material and methods. Ten single rooted teeth were prepared. Width and height of the teeth were measured by the marking points. This was followed by CT scanning, data conversion and rapid prototyping model fabrication. 2 methods were used; fused deposition modelling and stereolithography. Same width and height of this models were measured and compared to the original tooth. Results. Fused deposition modelling showed an enlarged width and reduced height. The stereolithography showed more exact data compared with the fused deposition modelling. Smaller standard deviation were recorded in the stereolithographic method. Overall width error from tooth to rapid prototyping was 7.15% in fused deposition modelling and 0.2% in stereolithography. Overall height showed the tendency of reducing dimensions. Conclusion. From the results of this study, stereolithography seems to be very predictable method of fabricating root analogue implant.

• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.1
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• pp.23-29
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• 2009

The ovate pontic was first described by Dewey and Zugsmith in 1933, but used clinically as a clinical alternative for esthetics in the late 1990s. The ovate pontic has been suggested as a more accurate duplication of emergence profile for natural teeth to provide an esthetic, cleanable prosthesis. If the resin temporary prosthesis with the ovate pontic is used during the healing period after the tooth extraction, it is possible to preserve the interdental papilla and eliminate or minimize the black triangle between the teeth. Ultimately it can become a esthetic final restoration without saliva leakage and phonetic discomfort. In this case we tried to treat the maxillary anterior area by the use of the ovate pontic and minimize the loss of the interdental papilla via duplicate the emergence profile of the natural tooth.

• Journal of Periodontal and Implant Science
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• v.23 no.3
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• pp.647-658
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• 1993

The purpose of this study is to examine the influence of 5% tetracycline(Tc) gel on healing of gingival tissue and change of diseased root surface when used with nonsurgical procedure. 7 patients with advanced periodontitis were received thorough scaling and root planning, followed by saline irrigation on 10 randomly selected control teeth and Tc gel application for 5 minutes with specifically designed plastic instrument of 10 test teeth in contralateral side. At 0, 1, 7, 14, and 21 days after treatment, biopsy and extraction were carried out. At day 7, Tc group showed decreased inflammation and delayed proliferation of pocket epithelium in comparison with control group which was continued for all experimental days. Scanning electron microscopic finding revealed demineralized and cleaned root surface with exposed dentinal tubules in Tc gel group. In the present study, clinically successful result is expected with combined use of nonsurgical periodontal therapy and intrapocket application of Tc gel.