• 대한소아치과학회지
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• 제30권2호
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• pp.189-195
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• 2003

본 연구의 목적은 레이저 형광법을 이용해 초기 치아우식증을 광학적으로 진단하기 위해 진단감도를 높이는 것이다. 소의 치아를 STPP 인공우식병소 유발용액에 침잠시키고 다양한 깊이의 병소를 유발한 후 표면에 아르곤 레이저를 이용해 형광현상을 유도하고 여러 가지 필터를 부착한 CCD 카메라로 이와 같은 형광현상을 촬영하여 컴퓨터로 전송하였다. 컴퓨터 영상분석 프로그램을 이용하여 병소 표면에서의 광밀도를 측정하였다. 이 실험에서 사용한 필터는 노랑색, 호박색, 오렌지색, 그리고 빨강색이였으며 광밀도를 측정한 후에는 치아 시편을 절단하여 편광현미경으로 실제 조직학적 병소의 깊이를 측정하고 병소의 깊이와 여러 가지 필터를 사용하여 측정한 병소 표면에서의 광밀도간의 상관관계를 분석하여 다음과 같은 결과를 얻었다. 1. 조직학적 병소의 깊이가 증가될수록 호박색과 오렌지색 필터를 사용하여 측정한 병소 표면에서의 광밀도는 증가되었다. 2. 병소 표면에서의 광밀도와 조직학적 병소의 깊이 사이의 상관계수는 오렌지색 필터가 가장 컸으며(r=0.49), 다음 호박색(r=0.32) 노랑색(r=0.13), 빨강색(r=0.01) 순 이였다. 3. 회귀분석결과 오렌지색 필터를 사용한 경우 병소표면에서의 광밀도와 조직학적 깊이 사이에 가장 직선에 가까운 회귀방정식을 나타내었다. 이상의 결과를 종합해 볼 때 오렌지색 필터가 건전치질과 우식치질 사이의 색조대비를 잘 표현하여 진단감도를 높일 수 있는 방법으로 생각되며 이와 같은 레이저 형광법으로 치아우식증의 조기탐지는 물론 비침습적 방법으로 치아우식증의 진행정도를 평가할 수 있을 것으로 사료된다.

• 대한소아치과학회지
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• 제26권1호
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• pp.109-118
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• 1999

The aim of this study was to evaluate the optical density of laser fluorescence for detection of incipient caries. Prepared and polished bovine enamel specimens were demineralized in a STPP solution for varying periods of time between 3 hrs. and 60 hrs. with an area of sound enamel retained on each specimen. The randomized specimens were analyzed for optical density of enamel demineralization using laser fluorescence. The specimens were sectioned and examined lesion depth by polarizing light microscope. Results were analyzed statistically with SAS program. The results from this study can be summarized as follows: 1. Optical density measured by laser fluorescence and lesion depth measured by polarizing light microscope was increased as demineralization time was increased(p<0.001). 2. Between optical density measured by laser fluorescence and lesion depth measured by polarizing light microscope was correlated highly(${\gamma}{\geq}0.74956$, p<0.001). 3. Regressive equation was obtained in this study as follows. Y=[X-0.260851]/0.000271(R-square:0.5618, p<0.001) (X:DENSITY, Y:DEPTH) In summary, optical density measured by laser fluorescence would be within the range of possibility to quantitatively presume demineralization amount of incipient caries lesion

• 대한소아치과학회지
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• 제25권4호
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• pp.849-857
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• 1998

The purpose of this study was to investigate whether fluoride-releasing pit and fissure sealant was more effective in preventing caries than conventional non-fluoride-releasing sealant. Specimens 8mm in diameter were made from sound bovine enamel. Fluoride-releasing pit and fissure sealant(Helioseal F, Vivadent, Schaan, Liechtenstein) and non-fluoride-releasing sealant(Helioseal, Vivadent, Schaan, Liechtenstein) were applied to the specimens and artificial caries was induced. Microhardness and the depth of the carious lesion was measured. The following results were obtained: 1. In group 2, sealed with fluoride-releasing sealant, there was a 58.4% decrease in microhardness. This was significantly less than the 84.4% decrease observed in group 1, sealed with non-fluoride-releasing sealant(p<0.01). 2. The average depth of the artificial carious lesion in group 2 was $30.1{\pm}9.8{\mu}m$. In group 1, sealed with non-fluoride-releasing sealant, the lesion was significantly deeper with an average depth of $58.5{\pm}4.9{\mu}m$(p<0.01). 3. Fluoride-releasing pit and fissure sealant was more anticariogenic compared to non-fluoride-releasing sealant.

• 치과방사선
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• 제28권1호
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• pp.37-46
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• 1998

The purpose of this study was to evaluate the diagnostic performance of the senior dental students for the proximal dental caries on intraoral radiographs and to compare it with the dental hospital residents, the reference group. It was also investigated the diagnostic performance according to the carious lesion depth. Thirty-five intraoral periapical and bitewing radiographs with 213 proximal surfaces included in this study were selected from the dental patients at Chonnam National University Hospital. The observers were 181 senior dental students from 5 dental schools and 40 dentists who were second year resident from 5 dental hospitals. They were asked to evaluate the presence or the absence of the proximal dental caries. The results were as follows: 1. The mean of the hitting rate for the overall observers was 184.51 surfaces and the diagnostic accuracy was 86.62％. 2. The diagnostic performance of the sound proximal tooth surfaces was very high, i.e., 91.5％ true negative rate and 8.5％ false positive rate. 3. The diagnostic performance of the dentist group was higher than the student group(P<0.05). 4. The proximal dental caries perceptibility increased as the lesion depth increased significantly(P<0.001) except no difference between the carious lesion depth III and IV (P>0.001).

• 대한소아치과학회지
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• 제24권1호
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• pp.313-324
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• 1997

The aim of the present study was to describe an safe and convenient method for the early detection of enamel caries using laser fluorescence. Fluorescence from natually carious lesion of human teeth illuminated by an argon laser(488nm) was observed and photographed using barrier filter. Intact enamel was found to fluorescence with a yellowish light. Whereas, incipient caries lesions in the enamel were dearly visible as dark areas in contrast to the fluorescence surroundings. For evaluation of accuracy of this method, lesion depth measured by the laser fluorescence in light microscope was compared with that polarizing microscope. The results from the present study can be summarized as follows : 1. Enamel caries of smooth surface was observed as pale white spot and undefined outline in ordinary light. Whereas, lesion was clearly visible as dark spot in laser fluorescence. 2. There was no difference between ordinary light view and laser fluorescence in occlusal surface and interproximal surface. 3. There was no significant difference between the lesion depth observed by laser fluorescence with light microscope and polarizing microscope. Apparent correlation exists between two groups.

• Restorative Dentistry and Endodontics
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• 제22권2호
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• pp.637-647
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• 1997

The purpose of this study was to evaluate the effect of concentration and pH of lactic acid on the formation of artificial root caries lesions formation in bovine teeth. The characterictics of artificially produced early root lesions were observed with polarized light microscope and the depth of lesions were mearsured with measuring microscope The results were as follows: 1. In the group of low pH and high concentration of lactic acid, the progress of lesion formation was faster than that of high pH and low concentration lactic acid group. 2. In the same group, initial lesion progress faster, but progression rate was reduced as time goes by. 3. In the development of initial root caries, cementum was act as a barrier to protect dentin from lesion progression.

• Restorative Dentistry and Endodontics
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• 제18권2호
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• pp.387-394
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• 1993

In order to investigate the effects of continuous and pH cyclic remineralization, artificial enamel carious lesions were produced on sections of about 2mm thickness of bovine incisor. 0.1M lactic acid solution adjusted to a pH of 4.3 and saturity of $2.98{\times}10^{-8}$ was used as demineralizing solution. The lesions were remineralized with the solution of pH 7.0 containing 1.5mM $CaCl_2$, 0.9 mM $KH_2PO_4$ and 20mM Hepes. In continuous remineralization procedure, the specimens were immersed in remineralizing solution continuously for 72 hours. In pH cyclic remineralization procedure, the sections were immersed in remineralizing solution for 6 hours and in dermineralizing solution for 20 minutes alternately during 72 hours. The effect of remineralization was determined by polarizing microscopy and electron microprobe analysis. The obtained results were as follows. 1. In case of continuous remineralization, the lesion depth was reduced partially or unchanged. 2. In pH cyclic condition, the thichness of surface layer and the lesion depth were increased simultaneously. 3. The mineral content of lesion was recovered to the level of sound enamel by remineraiization.

• 대한소아치과학회지
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• 제25권1호
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• pp.62-75
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• 1998

The main purpose of this study was to compare the anticariogenecity of glass ionomer restorative material polymerized by argon laser versus visible light, The results from the present study can be summarized as follows; 1. Under the polarized light microscope, the specimens of laser-cured group showed the shallower lesion body than that of visible-light cured group, both in the stage of lesion initiation and progression. 2. Glass ionomer material cured by visible light showed shallower body of lesion than that of composite resin cured by argon laser at the stage of lesion progression(p<0.05). It was suggested fluoride released from the glass ionomer might have the additive anticariogenic effect. 3. Statistical difference between groups on depth of lesion body was evident after lesion progression (p<0.05). It was suggested that anticariogenic effect by argon laser was more effective at the stage of lesion progression than the lesion initiation. 4. The increment of lesion body during progression was highest in group IV (p<0.05). 5. Based upon the above-mentioned results of this study, it can be concluded that the advantage of anticariogenic effect and short curing time of argon laser in glass ionomer polymerization should be considered in children and adolescents whose caries activity is relatively higher.

• 대한치과의사협회지
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• 제58권6호
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• pp.336-345
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• 2020

Peri-apical implant lesion, also known as 'retrograde peri-implantitis' can occur with multifactorial etiological factors. The purpose of this case report is to demonstrate resolution of periapical implant lesion by removal of causative factors and saving implant by regenerative therapy. A 54-year old male patient with mild dull pain around implant on the right mandibular second premolar area due to persistent peri-apical infection of the adjacent first premolar was treated. Extraction of tooth with symptomatic apical periodontitis and regenerative therapy on the buccal fenestration area of the implant and extraction site were performed. After 6-month reentry, notable regenerated bone tissue around implant was found, and implant placement on the previous extraction site was performed. After 14-month follow-up from the regenerative therapy, neither biological nor mechanical complication could be found around the implant, evidenced by high implant stability, normal clinical probing depth, and absence of discomfort spontaneously and during masticatory function. In conclusion, surgical intervention including regenerative therapy using bone graft and barrier membrane on periapical implant lesion can be suggested as one of the treatment options considering the extent of periapical lesion.

• Restorative Dentistry and Endodontics
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• 제39권1호
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• pp.51-55
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• 2014

The term "endo-perio" lesion has been proposed to describe the destructive lesion resulting from inflammatory products found in varying degrees in both the periodontium and the pulpal tissues. In most of the cases, clinical symptoms disappear following successful endodontic therapy. However failure after conventional root canal treatment calls for surgical intervention. A 35 year old male patient with endo-perio lesion in right maxillary lateral incisor was treated with platelet rich fibrin (PRF) and alloplastic bone substitute after conventional endodontic therapy. At the end of 6 months there was gain in clinical attachment, increased radiographic bone fill and reduction in probing depth which was maintained till 18 month follow-up. Present case report aims to evaluate the efficacy of PRF and alloplastic bone substitute in the management of intrabony defect associated with endo-perio lesion in maxillary lateral incisor because the healing potential of PRF and bone graft has not been widely studied in endodontics. The use of PRF allows the clinician to optimize tissue remodelling, wound healing and angiogenesis by the local delivery of growth factors and proteins. The novel technique described here enables the clinician to be benefited from the full regenerative capacity of this autologous biologic material.