• Journal of Periodontal and Implant Science
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• v.25 no.1
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• pp.14-23
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• 1995

Cyclosporin A is a powerful immunosuppressive agent commonly used for patients receiving organ transplants. Like phenytoin and the calcium channel blockers, the drug is associated with gingival overgrowth. The purpose of this study was to compare the correlation with gingival overgrowth score and clinical indices(i.e, : plaque index, papillary bleeding index, probing depth) and correlation with gingival overgrowth score and microorganism distribution in use of phase contrast microscope. After renal tranplant, taking cyclosporin A 40 patients participating in this investigation. Post - transplatation cyclosporin medication period was average $17.53{\pm}15.75$ months. In previous study reported that gingival overgrowth is an adverse side - effects seen in about 25-81% of patient taking cyclosporin A. The results were as follows : 1. Gingival overgrowth prevalence in taking cyclosporin A patients was 77.5%. Prevalence rate of region was anterior region(26 teeth, 55.3%), molar region(14 teeth, 29.8%), premolar region(7 teeth, 14.8%) in turns. Gingival overgrowth score by Angelopoulos & Goaz method was molar region($1.56{\pm}0.81$), anterior region($1.52{\pm}0.75$), premolar region($1.14{\pm}0.90$) in turns. 2. Medication period was not correlation with gingival overgrowth score. 3. Clinical indices and gingival overgrowth score were as follows. 1) Plaque index and gingival overgrowth score was significantly correlated(p

• The Journal of Korean Academy of Prosthodontics
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• v.14 no.1
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• pp.41-46
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• 1976

The purpose of the current study was to investigate histologic changes in the alveolar bone of the lower molar region subsequent to the loss of their opposite molars, and to characterize chemical alterations by utilization of histochemical procedures. Twenty five rats(Sprague Dawley), approximately 150-200gm body weight, were used in this experiment. In the treated animals, upper molars were removed. The animals were decapitated by groups at the following intervals after teeth removals: 10th, 20th, 50th, 70th and 100th day. The normal, untreated rats were used as controls. The molar region of lower jaw, including the intact alvelar bone and teeth was dissected and specimens were decalcified in 3% formic acid. After the tissues were fully decalcified, the specimens were embedded in celloidin and sectioned in mesiodistal plane. These sections were stained in the following staining methods. Mallory azan stain and hematoxylin-eosin stain were utilized for structural evaluation. Polysaccharides were demonstrated by means of the PAS reaction. Acidmucopolysaccharides were studied by means of the colloidal iron stain. Alloxan-Schiff reaction was used for protein. The results were as follows: 1) In the control animals, bone resorption was noted in the distal alveolar bone proper and bone apposition was shown in the mesial alveolar bone proper. But in the treated animals, bone apposition was observed on the mesial and distal walls of the alveolus and osteoclastic activity was not noted in any walls. 2) Bone apposition was most prominent from the 10th to 20th day after treatment. 3) Appositional growth of cementum along the surface of root was prominent from the 50th to 70th day after treatment. 4) In the area where osteoblastic activity was apparent, osteoblasts were stained strongly in the PAS and alloxan-Schiff reaction. A plastic resorption line showed strong alloxan-Schiff reaction. 5) In the colloidal iron stain, the alveolar wall adjacent to the cementum apposition area was stained more strongly than the other areas.

• The Journal of Korean Academy of Prosthodontics
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• v.31 no.4
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• pp.611-624
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• 1993

The purpose of this study was to analyze the stress distribution of the natural teeth, the implant, the prosthesis and the supporting tissue according to the types of implant and connection modality in the five-unit fixed partial denture with a implant pier abutment. A Two dimensional stress analysis model was constructed to represent a mandible missing the first and second premolars and first molar. The model contained a canine and second molar as abutment teeth and implant pier abutments with and without stress-absorbing element. Finite element models were created and analyzed using software ANSYS 4.4A for IBM 32bit personal computer. The results obtained were as follows. 1. Implant group, compared to the natural teeth group, showed a maximum principal stress at the superior portion of implants and a stress concentration at :he neck and end portion. 2. Maximum principal stress and maximum Von Mises stress were always lower in the case of rigid connection than nonrigid connection. 3. A cylinder type implant with stress absorbing element and screw type implant were generally similar in the stress distribution pattern. 4. A screw type implant, compared to the cylinder type implant, showed a relatively higher stress concentration at both neck and end portion of it. 5. Load B cases showed higher stress concentration on the posterior abutments in the case of nonrigid connector than rigid connector. 6. A maximum displacement was always lower in the case of rigid connection than nonrigid connection. These results suggest that osseointegrated implant can be used as an intermediate abutment.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.2
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• pp.323-336
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• 1996

This is a retrospective study on the patients with infection of the oral and maxillofacial region with the purpose of obtaining some useful data for diagnosis and treatment plan of that relatively common disease in dentistry. The used materials of study were 87 in total, including 52 male patients, 35 female patients who diagnosed and treated at the Department of the Dentistry in Hanyang Medical College Hospital for the period of Jan. 1990 to Dec. 1994. The author analyzed the distribution and incidence of sex, age, admission period, etiologic factors, etiologic teeth, treatment method of infections, pus culture, antibiotics sensibilities and medication. The result obtained as follows : 1. The developmental incidences by sex was superior in male by the ratio of 1.5 : 1 and the infection was most frequently occurred during the third decades(35.6%). 2. The number of admitted patients elevated in February, March, and April, and average of admission period was 9.8 days. 3. Main etiologic teeth showed on lower molar region in adult(63%) and upper molar region in primary dentition(46.1%). 4. Medications were administrated in all of the cases, and surgical incision and drainage were performed in 53% and extraction of the causative teeth were performed in 63.6% of all cases. 5. The most common involved fascial spaces were Buccal space(41.4%), Infraorbital space(27.6%), Submandibular space(16.1%),in order, and 9 cases(10.3%) were Ludwig's Angina. In 68.2% of the patients, and infection involved only one fascial space and in 21.8% of the patients, it involved to more fascial spaces. 6. The most causative organisms isolated from pus culture were Gram-positive facultative cocci(55.5%), and antibiotics sensitivities on the total isolated bacterial strains were exposed chloramphenicol(88.6%), Cephalothin(88.6%), Erythromycin(81.5%), Lincomycin(77.8%) in order, but it showed resistant on Gentamycin(58.3%), Tetracycline(56.5%), Methicillin(38.5%).

• The Journal of Advanced Prosthodontics
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• v.1 no.3
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• pp.140-144
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• 2009

STATEMENT OF PROBLEM. Little information is available about the buccal gingival level of multiple implant restorations. PURPOSE. This study was aimed to evaluate the relationship between width and height of buccal soft tissue around single and 2 adjacent implant restorations. MATERIAL AND METHODS. Four implant restoration groups (first and second molars, single second molars, posterior single restorations between teeth, and anterior single restorations between teeth) were randomly chosen from one dental institute. Each group comprised of 6 patients. After 6 months of function, silicone impressions were taken and stone models were fabricated for each restoration group. The stone models were cut in bucco-lingual direction at the most apical point of buccal gingival margin. The height and width of buccal supra-implant soft tissue were measured. One way ANOVA and Tukey HSD post hoc tests were performed to analyze the data obtained (P < .05). RESULTS. The most unfavorable width-height ratio was noted for the group, which was comprised of the second molar in the multiple adjacent (first and second molar) implant-supported restorations. The group also resulted in the shorter height of buccal supra-implant mucosa rather than that of anterior single implant restorations between natural teeth. CONCLUSION. To achieve a favorable level of buccal gingival margin, greater thickness of buccal supra-implant mucosa is required for the implant restorations without a neighboring natural tooth compared to the implant restorations next to a natural tooth.

• International Journal of Oral Biology
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• v.37 no.2
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• pp.77-83
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• 2012

We investigated the pulpal response to direct pulp capping in rat molar teeth using mineral trioxide aggregate (MTA) and calcium hydroxide (CH). A palatal cavity was prepared in rat maxillary molar teeth. Either MTA or CH was placed on the exposed pulp and all cavities were restored with composite. Rats were sacrificed for histological evaluation after 12 hours and at 2, 7, 14 and 21 days. In both the MTA and CH groups, reparative dentin formation was clearly observed on histology after 14 days. The MTA-capped pulps were found to be mostly free from inflammation, and hard tissue of a tubular consistent barrier was observed. In contrast, in CH-capped teeth, excessive formation of reparative dentin toward residual pulp was evident. The pulpal cell response beneath the reparative dentin layer was examined by immunofluorescence using antibodies against DSP. After 2 days, a few DSP immunopositive cells, most of which showed a cuboidal shape, appeared beneath the predentin layer. At 7 days, DSP-immunopositive cells with columnar odontoblast-like cells were seen beneath the newly formed hard tissues. At 14 and 21 days, DSP was more abundant in the vicinity of the odontoblastic process along the dentinal tubules than in the mineralized reparative dentin. The CH group showed strong expression patterns in terms of DSP immunoreactivity. Our results thus indicate that MTA may be a more effective pulp capping material as it induces the differentiation of odontoblast-like cells and the formation of reparative dentin without the loss of residual pulp functions.

• Imaging Science in Dentistry
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• v.47 no.3
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• pp.157-164
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• 2017

Purpose: This study determined and compared the distances from the maxillary root apices of posterior teeth to the floor of the maxillary sinus, or maxillary sinus distances(MSDs), and the distances from the mandibular root apices of the posterior teeth to the mandibular canal, or mandibular canal distances(MCDs), in Thai subjects with skeletal open bite and skeletal normal bite. Materials and Methods: Pretreatment cone-beam computed tomography (CBCT) images were obtained from 30 Thai orthodontic patients (15 patients with skeletal normal bite and 15 with skeletal open bite) whose ages ranged from 14 to 28 years. The CBCT images of the patients were processed and measured using the Romexis Viewer program. The MSDs and MCDs from the root apices of the maxillary and mandibular second premolar, first molar, and second molar to the maxillary sinus floor or the mandibular canal were measured perpendicularly to the occlusal plane. The Student t test was used for comparisons between the 2 groups. Results: The greatest mean MSDs were from the root apex of the second premolars in both groups, whereas the least mean MSDs were from the mesiobuccal root apex of the second molars. The greatest mean MCDs were from the mesial root apex of the first molars, whereas the least mean MCDs were from the distal root apex of the second molars. Conclusion: There were no differences in the mean MSDs or the mean MCDs between the skeletal normal bite group and the skeletal open bite group.

• The korean journal of orthodontics
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• v.53 no.3
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• pp.205-216
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• 2023

Objective: To investigate changes in the immature teeth of Sprague-Dawley rats during orthodontic treatment and to explore the changes in the peri-radicular alveolar bone through micro-computed tomography (CT). Methods: Twenty-five 26-day-old male Sprague-Dawley rats were included. The maxillary left first molar was moved mesially under a continuous force of 30 cN, and the right first molar served as the control. After orthodontic treatment for 7, 14, 21, 28, and 42 days, the root length, tooth volume, and alveolar bone mineral density (BMD) around the mesial root were measured through micro-CT. Results: The immature teeth continued to elongate after application of orthodontic force. The root length on the force side was significantly smaller than that on the control side, whereas the differences in the volume change between both sides were not statistically significant. Alveolar bone in the coronal part of the compression and tension sides showed no difference in BMD between the experimental and control groups. The BMD of the experimental group decreased from day 14 to day 42 in the apical part of the compression side and increased from day 7 to day 42 in the apical part of the tension side. The BMD of the experimental group decreased in the root apex part on day 7. Conclusions: The root length and volume of immature teeth showed continued development under orthodontic forces. Alveolar bone resorption was observed on the compression side, and bone formation was observed on the tension side.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.1
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• pp.22-28
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• 2011

Purpose: This article attempted to examine how teeth for restoration is made in a clinical practice and utilize it as future educational material of teeth formation and basic data for additional research. Materials and methods: This experiment investigated the models sent to milling center for production of zirconia crowns. After scanned with Lava CAD/CAM System (3M ESPE, Seefeld, Germany), they are measured on 'ImageJ (version 1.32j, National Institutes of Health, USA)' program and compared and analyzed. Convergence angle from mesio-distal surfaces and bucco-lingual surfaces of each teeth are measured. Also, bucco-lingual diameter of the region lowered as much as 0.4 mm from incisal edge in anterior teeth except canines.(This measure is defined as the Peak 0.4) The analysis of data between each group was conducted by Windows SPSS statistic program, and was proved significant on 95% confidence level by independent t-test, one-way ANOVA and multiple analysis (Sheff${\'{e}}$ test). Results: The mean value of convergence angle was $18.67^{\circ}$ It is ranked as molar ($26.70^{\circ}$) > premolar ($16.87^{\circ}$) > anterior teeth ($14.81^{\circ}$) in the order of mesio-distal convergence angle; anterior teeth ($22.32^{\circ}$) > molar ($20.93^{\circ}$) > premolar ($15.41^{\circ}$) in the order of bucco-lingual convergence angle. The mean value of Peak 0.4 was 1.18 mm. Conclusion: Convergence angle of abutment of zirconia all ceramic crown has difference depending on the location in the arch. Due to the nature of production of zirconia all ceramic crown, convergence angle of abutment and line angle finishing degree can have an effect on internal suitability of restoration.

• 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.