• The korean journal of orthodontics
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• v.39 no.1
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• pp.43-53
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• 2009

Objective: The purpose of this study was to compare the difference in three dimensional tooth movement using three different wire sizes($0.018{\times}0.025-in,\;0.016{\times}0.022-in$ 0.016-in) on a NiTi scissors-bite corrector. Methods: Computed tomography(CT) images of the experimental model before and after tooth movement were taken and reconstructed into three dimensional models for superimposition. The direction and the amount of tooth movement were measured and analyzed statistically. Results: The lingual and intrusive movements of the crown of the maxillary second molar were increased as the size of the NiTi wire increased. The roots of the maxillary second metals moved buccally except for the 0.016-in group. The intrusive movement of the roots of the maxillary second molars was increased as the size of the NiTi wire increased. Due to the use of orthodontic mini-implants, anchorage loss was under 0.2 mm on average. Conclusions: The $0.018{\times}0.025-in$ NiTi wire was most effective in lingual and intrusive movement of the maxillary second molar which was in scissors-bite position. Indirect skeletal anchorage with a single orthodontic mini-implant was rigid enough to prevent anchorage loss.

• Journal of Dental Rehabilitation and Applied Science
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• v.39 no.4
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• pp.204-213
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• 2023

Invasive or non-invasive reduction of fractures could be conducted as treatments of traumatic maxillofacial bone fractures. But when suboptimal reduction or malunion of maxillofacial bone fracture occurs, malocclusion could occur as a result of the lost relationship of the mandible and midface. This malocclusion is called post-traumatic malocclusion and orthognathic surgery, orthodontic treatment, selective grinding and prosthetic reconstruction are suggested as treatments for post-traumatic malocclusion after securement of stable TMJ. Stable TMJ is essential for occlusal rehabilitation to prevent occlusal change and relapse of malocclusion. Centric relation and adapted centric posture are suggested as start points of occlusal rehabilitation because they are most stable TMJ position. This case report presents a case in which post-traumatic malocclusion occurred after reduction of panfacial fracture. To rehabilitate full mouth occlusion, selective grinding and prosthetic reconstruction of implant supported fixed prostheses were conducted in centric relation and showed satisfying results in functional and occlusal aspects.

• Journal of Korean society of Dental Hygiene
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• v.10 no.4
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• pp.627-633
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• 2010

Objectives : The purpose of this study was to compare and analyse periodontal terminology of 16 dental hygiene textbooks including periodontology, dental prophylaxis for the standardization. Methods : 16 kinds of major publications were classified into the following criteria. - the standardization of translation, orthography, classification Results : 1. There are twelve cases, all told, of words with same origin used as different explanation and interpretation. Mucogingival Junction is most translated as '치은점막 경계' with high percentage of 53.8%, while Probe is translated as '치주낭 측정기' with 41.7% and Acquired Pellicle is translated as '획득피막' with 57.1%. In addition, Stippling is interpreted as '점몰' with high percentage of 70%, and Supine Position is interpreted as '수평자세' or '앙와위' with 33.3%. Yet, Pen Grasp is explained differently in all five books, whereas Modified Pen Grasp is explained as '변형 연필 잡기법' with 57.1%. The rest, Palm Thumb Grasp and Adaptation, have different interpretation in books, requiring unified interpretation of terms. 2. There are two cases of loanwords expressed according to orthography. Implant is expressed as '임플란트'(87.5%) and '임프란트'(12.5%). Scaling is expressed as '스켈링'(40.0%) and '스케일링'(60.0%). 3. There are four cases of same terms classified in a different way. Classification of 'Probing시 압력' and '치주인대섬유군' concurs only 50.0% in six books. '치석제거 시술자의 위치' is classified differently in all six books, while '정상치은 열구 깊이' concurred 45.5% in books. Conclusions : In conclusion, related academic majors and writers should provide cohesive explanation and interpretation of terms for unification of terminology in the field of periodontics as well as higher level of understanding and learning opportunities for students. Furthermore, description of all terms should be reviewed and analyzed comprehensively based on existing classification criteria in order to provide best standard explanation.

• Journal of Periodontal and Implant Science
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• v.29 no.3
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• pp.621-636
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• 1999

When mucoperiosteal flaps are positioned and sutured to desirable position, the wound contains several interface between tissues which differ fundamentally in composition & biological reaction. Thus the C-T surface of the flap will, on one hand, oppose another vascularized surface, and on the other, the avascular dental material for example, when root resoptions, fractured root, endodontic perforation, deep root carious lesions were filled with amalgam, glass ionomer, resin etc. Recently, a number of case report described the successful treatment of a subgingival root lesion with restorative material & free gingival graft, open flap surgery, but more objective research was needed . Most of study on restorative materials were concerned for cytotoxicity not for actual healing event on that materials and its influencing factors such as biocompatibility, surface wettability, surface topography . The aim of this in vitro study was to evaluate the effect of amalgam, resin modified glass ionomer, composite resin per se, and their surface roughness on the growth of human gingival fibroblast. The cells were obtained and placed on culture flask and incubated for 3 days with the prepared test materials. Then count the attached cell number with hemocytometer,(n=12) and 2 samples were examined with SEM about attachment cell morphology . Another 4 samples were evaluated on their surface roughness with Talysurf and average surface roughness value(Ra) were obtained. Statistical difference in attached cell number, roughness value were analyzed using ANOVA. The number of attached cell was as follows, for root dentin specimen 16.7${\pm}$4.41, resin modified glass ionomer 14.0${\pm}$4.15, resin 8.13${\pm}$3.63, amalgam 0.72${\pm}$3.33(${\times}10^3$). Between root dentin and resin-modified glass ionomer, no significant difference was observed, but resin, amalgam showed a significant less cell numbers than for root dentin, resin modified glass ionomer cement. SEM examination expressed many cell surface attachment apparatus in root dentin and resin modified glass ionomer specimens. For resin specimen, cell attachment was observed but exposed less appratus. The average surface roughness value are following results. Dentin specimen 0.6972${\pm}$ 0.104, resin modified glass ionomer 0.0822${\pm}$0.009, resin 0.0875${\pm}$0.005, amalgam 4.2145${\pm}$0.985(${\mu}m$). Between root dentin, resin-modified glass ionomer, and resin, no significant difference was observed, but amalgam showed a significant more rough surface than other groups. When evlauated the interrelationship between cell attachment and surface roughness, therefore, there was weak reverse correlation.(pearson correlation : - 0.593) These results suggest that resin modified glass ionomer have the favorable healing potential when used for subgingival restoration. And for relationship between cell attachment and surface characteristics, further investigations were needed.

• Journal of Periodontal and Implant Science
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• v.37 no.3
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• pp.563-573
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• 2007

Genetic polymorphisms associated with aggressive periodontitis have previously been reported. Interleukin-10 is an immunoregulatory cytokine that plays a role in the pathogenesis of periodontitis. Individual capacity for IL-10 production appears to be under genetic influence, The aim of present investigation was to explore possible genetic association of IL-10 gene promoter polymorphisms with generalized aggressive periodontitis. The study population consisted of 37 generalized aggressive periodontitis patients from the Department of Periodontology, Chonnam National University Hospital and 27 control subjects, all the subjects were non-smokers, Genomic DNA was obtained from buccal swab. The IL-10promoter -597, -824, -1082 positions were genotyped by amplifying the polymorphic regions using polymerase chain reaction (PCR) , followed by restriction enzyme digestion and gel electrophoresis. IL-10-597 C (allele 1) to A (allele 2) and IL-10-824 C (allele 1) to T (allele 2) and IL-10-1082 G (allele 1) to A (allele 2) polymorphisms were examined. The results were as follows. 1. In patients, the distribution of genotypes C/C, C/A and NA at Il-10-597 was determined to be 13.5%, 37.8% and 48.7%, respectively and the distribution of genotypes at IL-10-824 was the same as that of IL-10-597. The distribution of genotypes G/G, G/A and NA at IL-10-1082 was found to be 2.7%, 16.2% and 81. 4%, respectively. No statistical difference in genotype distribution was found between the patient and control groups. 2. Allele 2 carriage rate at the three position of the IL-10 promoter region was higher in the control group than the patient group. 3. Allele 2 frequencies at IL-10-597 and -824 positions were higher in female group than male group and its difference was statistically significant(p<0.05). No significant difference in genotype distribution between the control and patient groups. Allele frequency between control and patient groups was not significantly different although allele 2 frequency at the three positions in the IL-10 promoter region appeared to be higher in control group. In conclusion, no clear association between IL-10 gene promoter polymorphisms and generalized aggressive periodontitis in Korean was observed.

• Journal of Periodontal and Implant Science
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• v.26 no.3
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• pp.735-751
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• 1996

An ultimate goal of periodontal therapy is to stop the disease process and to regenerate a functionally-oriented periodontium destroyed as a result of periodontal disease. The purpose of this study was to observe the effect of grafting granulation tissue obtained from extraction socket on the regeneration of horizontal furcation defect. Six dogs were used in this study. All mandibular first and third premolars were extracted. At 2, 3, and 5 days after extraction, tissues were obtained from extraction socket of 1 mongrel dog and examined by light microscope. Granulation tissue obtained at 5 days after extraction was chosen as the graft material. Five days later, horizontal furcation defects were created surgically at mandibular second and fourth premolars in the right and left side of the 5 beagle dogs. The entrance area of the artificially prepared "key hole" defects were about $3\;4mm^2$. By random selections, 2 exposed furcation defects were grafted with granulation tissue obtained from extraction socket as experimental group and 1 furcation defect was as control. The flaps were replaced to their original position and sutured with 4-0 chromic cat-gut. Three dogs were sacrificed 4 weeks and two dogs 8 weeks after surgery, and the prepared specimens were examined by light microscope. At 4 weeks, furcations were filled with epithelial lining and fibrous connective tissue infiltrated with chronic inflammatory cells. New bone formation was observed in all groups. Only experimental group showed new cementum formation. At 8 weeks, new cementum, functional arrangement of new PDL fiber, root resorption, and some ankylotic union of newly formed alveolar bone and root surface were observed in all groups. Experimental group showed that epithelial downgrowth was inhibited and new bone formation was more active compared to control. The success rate of the furcation defect healing was higher in experimental group than control. These results suggested that grafting of granulation tissue obtained from extraction socket which combined with reconstructive periodontal flap surgery may promote periodontal regeneration of horizontal furcation defect.

• Journal of Periodontal and Implant Science
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• v.38 no.4
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• pp.579-588
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• 2008

Purpose: The purpose of this study was to investigate the association of generalized aggressive periodontitis with IL-6 promoter gene single nucleotide polymorphisms(SNP). Material and Methods: The study population consisted of 52 generalized aggressive periodontitis patients(GAP) and 30 periodontally healthy control subjects, who were systemically healthy non-smokers. Genomic DNA was obtained from buccal swab. The IL-6 promotor SNP at the positions of -597, -572, and -174 were genotyped by amplifying the polymorphic region using polymerase chain reaction(PCR), restriction enzyme digestion and gel electrophoresis. Result: The genotype distributions for G/G, G/A and A/A genotypes of IL-6 -597 were 30.8%, 40.4%, and 28.8% in the GAP group and 53.3%, 40%, and 6.7% in the control group and were statistically different between 2 groups(p<0.05). Allele 2 frequency of IL-6 -597 were significantly higher in the GAP group than the control group(p<0.01). At the position of IL-6 -572, the distribution for C/C, C/G and G/G genotypes were 23.1%, 55.8% and 21.2% in the GAP group and 20%, 33.3%, and 46.7% in the control group. In female subjects, the genotype distribution were significantly different between 2 groups(p<0.01). In male subjects, allele 2 frequency of IL-6-572 was significantly lower in the GAP group than the control group(p<0.05). The genotype distribution of IL-6 -174 in the GAP group were 96.2%, 3.8% for G/G, G/C genotypes whereas only the G/G genotype was detected in the control group. Conclusion: In conclusion, significant associations were found in IL-6 gene promoter(-597, -572) polymorphisms and generalized aggressive periodontitis. Further cohort study will be necessary in larger population.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.1
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• pp.101-110
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• 2013

$T4K^{TM}$(Myofunctional Research Co, Australia) is one of the myofunctional appliance developed to be used in children of mixed dentition. Myofuncitonal appliance stimulate the facial, masticatory and tongue muscle and help to balance the muscular force. Labial bow included in the device exerts strength in excessively labial inclineded upper jaw, Lip bumper blocks strength of the mouth to prevent abnormal strength exerted in lower jaw, Tongue tag secures proper position of tongue, and additional exercise is not required for child patients. For the more, simpler design and softer texture of device prmoted cooperation of patients during use. This case report is to present the satisfactory results gained by using $T4K^{TM}$ on Class II patients. Comment 1. $T4K^{TM}$ was applied in Class II malocclusion patients of mixed dentition with expected space insufficient to gain facial improvement. 2. Excessive overjet, overbite were improved. 3. Main effects are regarded to have been achieved by development of lingual slant of upper jaw, labial slant of lower jaw, and lower part of jawbone. 4. Bad habits, such as mouth breathing, can also be adjusted.

• Radiation Oncology Journal
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• v.12 no.2
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• pp.243-252
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• 1994

The use of high dose rate remote afterloading system for the treatment of intraluminal lesions necessitates the need for a more accurate of dose distributions around the high intensity brachytherapy sources, doses are often prescribed to a distance of few centimeters from the linear source, and in this range the dose distribution is very difficult to assess. Accurated and optimized dose calculation with stable numerical algorithms by PC level computer was required to treatment intraluminal lesions by high dose rate brachytherapy system. The exposure rate from sources was calculated with Sievert integral and dose rate in tissue was calculated with Meisberger equation, An algorithm for generating a treatment plan with optimized dose distribution was developed for high dose rate intraluminal radiotherapy. The treatment volume becomes the locus of the constrained target surface points that is the specified radial distance from the source dwelling positions. The treatment target volume may be alternately outlined on an x-ray film of the implant dummy sources. The routine used a linear programming formulism to compute which dwell time at each position to irradiate the constrained dose rate at the target surface points while minimizing the total volume integrated dose to the patient. The exposure rate and the dose distribution to be confirmed the result of calculation with algorithm were measured with film dosimetry, TLD and small size ion chambers.

• Journal of Periodontal and Implant Science
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• v.31 no.1
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• pp.243-258
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• 2001

Gingival recession is exposure of the root surface with apical shift in the position of gingiva. The incidence of gingival recession is 8% in children and 100% after the age of 50. Recession tends to be found in patients with healthy gingiva, but more frequentely found in patients with periodontal disease, and it often causes mucogingival defects. Buccal surface of premolar is the area not only for severe gingival recession and cervical abrasion, but also the area of numbers of buccal frenum and less keratinized gingiva. Threrfore, the goal of this study was to observe the patients with periodontitis and examine whether there are clinical relations between gingival recession and cervical abrasion of premolar and other factors related with the condition of periodontal health. Generally healthy 218 patients who had periodontitis, aged between 18 and 78, were examined for depth of periodontal poket, width of attached gingival, gingival recession, cervical abrasion, and frenum of mid-buccal surface of premolar at the Department of Periodontics in Dankook University Dental Hospital and following is the result. 1. The average gingival recession and cervical abrasion of premolar with periodontal disease was 0.76mm and 0.29mm and each has 43% and 14% of incidence. Also the width of attached gingiva of mid-buccal surface was 1.77mm. the average periodontal pocket depth is 2.0mm and 47% of frequently seen was narrow single shaped frenum, and the interdistance of the frenum was mostly over 4mm. 2. With statistical significance(P<0.05), the incidence of gingival recession increased with age and was related much more with female than male, the first premolar than the second premolar, and with narrow attached gingiva and frenum. 3. With statistical significance(p<0.05), the incidence of cervical abrasion increased with age and was related with the area of the first premolar and narrow attached gingiva, but the sexual and frenum differences were not statistically significant (p>0.05). 4. The severity of gingival recession increased with age and was more related with female than male, the first premolar than the second premolar. And the area of narrow attached gingiva and frenum showed more gingival recession and the distance of frenum was more highly related than shape, and they were statistically significant (p<0.05). 5. With statistical significance(p<0.05), the severity of cervical abrasion increase with age and was observed at the first premolar and narrow attached gingiva. But the sexual and frenum differences were not statistically significant (p>0.05).