• 대한소아치과학회지
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• 제45권3호
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• pp.344-353
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• 2018

이 연구의 목적은 mineral tiroxide aggregate의 긴 경화시간과 치아변색 등의 단점으로 인해 이를 대체하고자 최근 주목받고 있는 재료인 tricalcium silicate를 기반으로 한 치수복조제 중 Biodentine의 미세누출과 최종수복제로 가장 많이 쓰이는 composite resin간의 전단결합강도에 대하여 경화시간에 따른 차이를 비교 평가하는 것이다. 미세누출 평가를 위해 소 치아 70개를 이용하여 순면에 와동을 형성한 후 Biodentine을 충전하고 무작위로 10개씩 하위 군으로 나누어 12분, 45분, 24시간, 48시간, 1주일, 2주일, 1개월로 경화시간을 달리한 후 상방에 composite resin을 적용하여 시편을 제작하였다. 미세누출 평가를 위해 표본을 24시간 동안 0.5% fuchsin 용액에 침적한 뒤, 수세하고 건조하여 각 표본을 수주 하 디스크를 이용해 절반으로 나누어 20배의 비율로 실체현미경(Olympus SZ61, Olympus, Tokyo, Japan)을 사용하여 관찰하였다. 전단결합강도 평가를 위해 중심구를 가진 아크릴 레진 블록을 210개를 제작하고 중심구에 Biodentine을 채운 후 각각 30개씩 7개 군으로 나누어 12분, 45분, 24시간, 48시간, 1주일, 2주일, 1개월 경화시간 경과 후 상방에 composite resin을 적용하여 시편을 제작하였다. Universal testing machine을 이용하여 경화시간에 따른 전단결합강도를 측정하였다. 연구결과, 미세누출에 있어서 24시간 이상 Biodentine 경화 후 상방에 composite resin 수복을 시행한 경우 미세누출을 최소화 하는 것으로 나타났다. 또한 전단결합강도에 있어서도 Biodentine의 경화시간이 24시간 이상일 경우 composite resin의 중합수축을 상쇄할 수 있는 전단결합강도가 측정되었다. composite resin 수복 전 Biodentine을 24시간 이상 경화시키는 것이 임상적으로 더 나은 결과를 나타낼 것이다.

• Restorative Dentistry and Endodontics
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• 제23권1호
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• pp.433-442
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• 1998

The purpose of this study was to observe the changes of acidity of resin cement(Time Line), glass ionomer cement(GC Fugi Lining LC), zinc phosphate cement(Fleck's zinc cement). zinc oxide eugenol cement(Sultan,Chemists.) in vivo and in vitro. Class I cavities with 3mm depth were prepared on the occlusal surfaces of 20 recently extracted human Mn. molar teeth and 20 human Mn. 3rd molar teeth in oral cavity. The prepared cavities were divided into 4 groups of each 5 teeth using the above 4 cavity liners. Each cement was mixed in accordance with manufacturer's direction at the room temperature of $23^{\circ}{\pm}5^{\circ}C$ and filled into the cavity in a width of 1 mm. The microelectrode of pH meter was inserted into the prepared cavity which was filled with mixed cement, and the acidity of cement was measured for 3 days from the beginning of cement mix in vitro and in vivo. The measured acidity was then statistically analyzed by ANOVA. The results were as follows. 1. In vitro, the pH of zinc oxide eugenol cement was statistically lower than that of the three other groups at 2min, 4min, 6min, 8min, 10min, 12min, 18min, 20min. (p<0.05). 2. The pH of zinc oxide eugenol cement in vivo was statistically higher than that in vitro at 16min,16min, 20min(p<0.05). 3. The pH of zinc phosphate cement in vivo was statistically higher than that in vitro at 4min, 20min(p<0.05). 4. In vitro and in vivo, there was no significant difference in the pH between the resin cement and the glass ionomer cement(p>0.05). 5. The initial acidity was not high, but almost neutral in all kinds of the cements.

• 대한소아치과학회지
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• 제36권4호
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• pp.539-549
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• 2009

본 연구는 소년원학교 학생의 치아우식증, 치주조직 상태와 구강건강에 대한 실태 및 인식도를 조사하기 위해 경기도 지역 소년원학교에 수용되어 있는 13~20세 남녀 청소년 342명의 우식, 상실, 충전 치아 수와, 상하악 좌우 제1대구치와 상악 우측 중절치, 하악 좌측 중절치의 출혈/치석/치주낭 존재 유무를 검사하였으며, 구강건강에 대한 인식도에 대한 설문조사를 시행하여 다음과 같은 결과를 얻었다. 1. 2006년 국민구강건강실태 조사와 비교할 때, 일반청소년에 비해 소년원학교 학생의 우식 치아, 우식경험 영구치, 출혈, 치석, 천치주낭을 보이는 치아 수가 많았다. 2. 여자가 남자보다 우식경험 영구치 수가 많았으나(p<0.05),건전 치주조직을 보이는 치아 수는 많고, 천치주낭을 보이는 치아 수는 더 적었다(p<0.05). 3. 여자가 남자보다 자신의 구강건강이 나쁘다고 생각하는 비율이 높았으며(p<0.05), 대다수(79.2%) 청소년이 구강건강이 중요하다고 응답하였다. 4. 소년원학교 학생의 71.5%가 치과치료에 대한 불안이 있다고 응답하였으며, 여자가 남자보다 그 비율이 높았다(p<0.05).

• Restorative Dentistry and Endodontics
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• 제30권1호
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• pp.16-21
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• 2005

본 실험에서는 근관 충전 후 Streptococcus mutans를 이용하여 포스트 와동 형성 전후의 근관부미세 누출을 비교하였다. 40개의 발치된 치아를 치근단의 길이가 14 mm가 되도록 치관부를 제거한 뒤, 06 taper $Profile^{(R)}$로 MAF 크기가 $\#40$이 되게 근관 확대를 시행하였다. 근관 확대 후 continuous wave technique으로 근관 충전을 시행하였다. 실험군은 다음과 같다. 1군은 양성 대조군으로 sealer 없이 근관 충전 하였다. 2군은 음성 대조군으로 sticky wax로 치근면을 완전히 막았다. 3군은 근관 충전 후 전체 길이를 14 mm로 유지하였다. 4군은 근관 충전 후 거타퍼치를 5 mm 길이로 남겨두고 포스트 와동을 형성하였다. 치근을 플라스틱 튜브 안에 위치시켜 치근첨은 Andrade's indicator가 첨가되어 있는 BHI 배지에 접촉되도록 하고 상부에서는 bacteria가 유입되도록 하였다. 실험군 3에서의 색변화는 평균 27.2일 만에 일어났으며 포스트 와동 형성한 4군은 평균 15.7일만에 색변화가 일어났으며 3군과 4군 사이에 통계학적으로 유의차를 나타내었다(P = 0.0007).

• 대한치과보철학회지
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• 제36권4호
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• pp.549-565
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• 1998

Porcelain is considered to be one of the materials of choice for restoration where esthetics is of concern. But porcelain surface without final glazing treatment may induce undesirable results such as inflammatory response on adjacent soft tissues due to plaque accumulation and increased wear of opposing teeth. Therefore, rough porcelain surface must be smoothened by final glazing treatment or chairside polishing procedure. The purpose of this study was to compare the surface roughness among self-glazed, overglazed and polished porcelain with various polishing kit, and to detect which phase of polishing is optimal in clinic. Specimens were fabricated with Vita VMK porcelain. The surface treatment of each group was performed as follows. Group 1 : overglazing treatment Group 2 : self-glazing treatment Group 3 : polishing with the Truluster Polishing System for Porcelain(Brasseler, U.S.A.) Group 4 : polishing with the Exa Cerapol Adjustment kit (Edenta dental products, Switzerland) followed by finishing with diamond-filled polishing paste Group 5 : polishing with the Shofu Porcelain Adjustment kit (Shofu inc., Japan) followed by finishing with diamond-filled polishing paste. At each polishing steps, the measurement of Ra and Rq values were performed, and the surface was examined by scanning electron microscope. The results were as follows : 1. Overglazing treatment brought smoother surface than self-glazing treatment. 2. Polishing systems without porcelain polishing paste did not make better result than self-glazing treatment. 3. Polishing system with porcelain polishing paste made similar result to overglazing treatment. 4. Applying diamond-filled polishing paste after using polishing system which has no porcelain polishing paste produced surface as smooth as overglazing treatment does.

• Restorative Dentistry and Endodontics
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• 제14권2호
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• pp.49-64
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• 1989

The purpose of this study was to evaluate the effect of several materials on the healing process of apical wound. Sixteen mandibular premolars obtained from 4 healthy dogs were used for this study. Under general anesthesia, the pulpal chamber of each tooth was opened and the pulps were extirpated. The root canals were then instrumented with H-file and irrigated with physiologic saline solution ; the apices were purposely perforated and enlarged with the engine K-reamer. In the experimental groups, apical wounds were filled with one of calcium hydroxide, hydroxylapatite, and tricalcium phosphate materials, mixture of each materials and physiologic saline solution, with a lentulo spiral. In the control group, apical wounds were not filled with any material. All the root canals were filled by the lateral condensation technique with gutta-percha cone and ZOE sealer. The access opening of all the teeth were closed with amalgam. On the 10, 20, 40 and 60th day after experiment, experimental animals were sacrificed. Segments of jaws, each containing one tooth, were fixed in 10% formalin solution and decalcified in Plank-Rychlo solution. The specimens were embedded in paraffin and serially sectioned to an average thickness of $6{\mu}m$. The sections were stained by hematoxylin-eosin and Masson's trichrome stain method and examined under light microscope. The results were as follows : 1. In the experimental groups, the new bone formations were observed in apical wounds. 2. Fourty days later, apical wounds were healed by granulation tissue in the experimental groups, but were not healed by granulation tissue in the control group, and the healing process of experimental groups were more rapid than that of control group. 3. Sixty days later, chronic inflammation disappeared in the experimental groups, and the materials used showed biologic affinity to the periapical tissue. 4. In all the groups, the resorption of cementum appeared on the 10th and 20th day after experiment, and the deposition of cementum appeared on the 40th and 60th day after experiment, especially showing narrowness of apical foramen due to newly formed cementum in calcium hydroxide group. 5. Calcum hydroxide and tricalcium phosphate particles were gradually resolved, but hydroxylapatite particles were not resolved through the experimental period.

• Restorative Dentistry and Endodontics
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• 제16권1호
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• pp.121-132
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• 1991

The purpose of the study was to evaluate the marginal sealing effect of composite resin inlays according to the luting techniques and compare them to the conventional direct resin filling technique. 90 cavities of class V were prepared on the buccal surface of 90 extracted molar teeth, which were divided into four groups. Cavities of control group were directly filled with Scotchbond 2 and P - 50, and those of composite resin inlay groups were luted with one of the followings: Adhesive bond followed by Adhesive cement, All bond followed by Adhesive cement, Fuji - ionomer type L All the specimens were immersed in India ink dye solution for 7 days at $37^{\circ}C$ incubator after thermocycling between $5^{\circ}C$ and $60^{\circ}C$ and longitudinally sectioned with diamond disk inot two parts All the specimens were observed at the occlusal and gingival margins and statistical analysis was performed. The results were as follows: 1. Groups filled with composite resin inlay showed less marginal leakage than the group directly filled(p<0.01). 2. There was no significant difference in marginal leakage between composite resin inlay groups luted with Adhesive bond followed by Adhesive cement and the group luted with All bond followed by Adhesive cement(p>0.05). 3. At occlusal margins, Composite resin inlay group luted with Adhesive bond followed by Adhesive cement showed less marginal leakage than the group luted with Fuii ionomer type I(p<0.01). At gingival margins, composite resin inlay group luted with All bond followed by Adhesive cement showed less marignal leakage than the group luted with Fuji ionomer type I(P<0.01).

• Restorative Dentistry and Endodontics
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• 제12권1호
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• pp.107-116
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• 1986

The primary aim of this study was to assess the effects of the margin designs and composite resins on the marginal leakage of Class V resin restorations. 60 Class V cavities with $90^{\circ}$ butt joint, 60 with $45^{\circ}$ bevel joint, and 60 with concave joint were prepared on the labial surfaces of 38 extracted anterior teeth and the buccal and lingual surfaces of 71 premolars, and classified as the butt group, bevel group and concave group, respectively. After completion of the cavity preparation, Heliosit${(R)}$ was filled in 20 butt joint cavities, 20 bevel joint cavities, and 20 concave cavities. And Hi-Pol$^{(R)}$ and Palfique$^{(R)}$ were filled in the same manner, respectively. After finishing, all specimens were subjected manually to 50 thermal cycles at $4^{\circ}C$, $37^{\circ}C$, and $60^{\circ}C$. They were immersed in 0.5% methylene blue solution for 24 hours, and buccolingually sectioned with sectioning machine. The sectioned specimens were examined under the light microscope. The results indicated the following: 1. The bevel group showed the least amount of marginal leakage compared with the other two design groups, but the statistical analysis showed no significant difference at the 95% confidence level. 2. Hi-Pol$^{(R)}$ group showed the most severe marginal leakage compared with the other composite resin materials, but there was no significant difference in the groups. 3. The bevel-Heliosit$^{(R)}$ subgroup, which was filled with Heliosit$^{(R)}$ in the beveled cavities, showed the least amount of marginal leakage, but there was no significance in all the subgroups.

• Restorative Dentistry and Endodontics
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• 제37권1호
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• pp.41-49
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• 2012

Objectives: The internal adaptation of composite restorations with or without resin modified glass ionomer cement (RMGIC) was analyzed non-destructively using Microcomputed tomography (micro-CT). Materials and Methods: Thirty intact human teeth were used. The specimens were divided into 3 groups. In the control group, the cavities were etched with 10% phosphoric acid for 15 sec. Composite resin was filled into the cavity without adhesive. In group 1, light cured glass ionomer cement (GIC, Fuji II LC, GC) was applied as a base. The cavities were then etched, bonded, light cured and filled with composites. In group 2, the cavities were then etched, bonded, light cured and filled with composites without base application. They were immersed in a 25% silver nitrate solution. Micro-CT was performed before and after mechanical loading. One-way ANOVA with Duncan analysis was used to compare the internal adaptation between the groups before or after loading. A paired t-test was used to compare internal adaptation before and after mechanical loading. All statistical inferences were made within the 95% confidence interval. Results: The silver nitrate solution successfully penetrated into the dentinal tubules from the pulp spaces, and infiltrated into the gap between restoration and pulpal floor. Group 2 showed a lower adaptation than the control group and group 1 (p < 0.05). There was no significant difference between the control group and group 1. For all groups, there was a significant difference between before and after mechanical loading (p < 0.05). Conclusions: The internal adaptation before and after loading was better when composites were bonded to tooth using adhesive than composites based with RMGIC.

• Journal of Periodontal and Implant Science
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• 제32권1호
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• pp.161-172
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• 2002

The present study evaluated the effects of guided tissue regeneration using xenograft material(deproteinated bovine bone powder), with and without biodegradable membrane in beagle dogs. Contralateral fenestration defects (6 ${\times}$ 4mm) were created 4 mm apical to the buccal alveolar crest of maxillary premolar teeth in 5 beagle dogs. Deproteinated bovine bone powders were implanted into fenestration defect and one randomly covered biodegradable membrane (experimental group). Biodegradable membrane was used to provide GTR. Tissue blocks including defects with soft tissues which were harvested following four & eight weeks healing interval, prepared for histo-phathologic analysis. The results of this study were as follows. 1. In control group, at 4 weeks after surgery, new bony trabecular contacted with interstitial tissue and osteocytes like cell were arranged in new bony trabecule. Bony lamellation was not observed. 2. In control gruop, at 8 weeks after surgery, scar-like interstitial tissue was filled defect and bony trabecule form lamellation. New bony trabecular was contacted with interstitial tissue but defect was not filled yet. 3. In experimental group, at 4 weeks after surgery, new bony trabecular partially recovered around damaged bone. But new bony trabecular was observed as irregularity and lower density. 4. In experimental group, at 8 weeks after surgery, lamella bone trabecular developed around bone cavity and damaged tissue was replaced with dense interstitial tissue. In conclusion, new bone formation regenerated more in experimental than control groups and there was seen observe more regular bony trabecular in experimental than control groups at 4 weeks after surgery. In control group, at 8 weeks after surgery, the defects was filled with scar-like interstitial tissue but, in experimental group, the defects was connected with new bone. Therefore xenograft material had osteoconduction but could not fill the defects. We thought that the effective regeneration of periodontal tissue, could be achieved using GTR with biodegradable membrane.