• 한국융합학회논문지
• /
• 제8권1호
• /
• pp.89-96
• /
• 2017

본 연구의 목적은 치과임상에서 불소 바니쉬 선택 시 고려해야 할 정보를 제공하고자 국내에서 사용하는 모든 불소 바니쉬를 선정하여 초기우식병소의 재광화 효과를 분석하고자 하였다. 7종의 불소 바니쉬를 무작위 배분하여 영구치(56)는 7종(CS, MI, CW, VV, EP, FP, FN)을, 유치(20)는 그중 CS, MI, CW, FP를 사용하였다. 시편은 네일바니쉬로 $3{\times}3mm^2$ 윈도우 형성 후 4일간 탈회시키고, 영구치와 유치로 구분하여 불소 바니쉬 도포 후 1주간 인공타액에서 교반하였다. QLF-D을 이용하여 우식 병소크기 변화를 분석한 결과, 영구치에서 바니쉬 도포전에 비해 도포 후 CS(4,64), MI(4.86), CW(4.50), EP(5.50)바니쉬가 ${\Delta}F$값이 감소하였고, 유치에서 FP(3.00), MI(3.00)바니쉬에서 재광화 효과가 나타났다. 그러므로 MI바니쉬는 치과임상에서 성인과 아동 모두에게 우식예방을 위한 불소도포 제제로 유용하게 활용될 수 있을 것이다.

• Imaging Science in Dentistry
• /
• 제43권3호
• /
• pp.171-177
• /
• 2013

Purpose: The purpose of this study was to compare the efficacy of two imaging modes in a cone beam computed tomography (CBCT) system in detecting root fracture in endodontically-treated teeth with fiber posts or screw posts by selecting two fields of view. Materials and Methods: In this study, 78 endodontically-treated single canal premolars were included. A post space was created in all of them. Then the teeth were randomly set in one of 6 artificial dental arches. In 39 of the 78 teeth set in the 6 dental arches, a root fracture was intentionally created. Next, a fiber post and a screw post were cemented into 26 teeth having equal the root fractures. High resolution (HiRes) and standard zoom images were provided by a CBCT device. Upon considering the reconstructed images, two observers in agreement with each other confirmed the presence or absence of root fracture. A McNemar test was used for comparing the results of the two modes. Results: The frequency of making a correct diagnosis using the HiRes zoom imaging mode was 71.8% and in standard zoom was 59%. The overall sensitivity and specificity in diagnosing root fracture in the HiRes mode were 71.79% and 46.15% and in the standard zoom modes were 58.97% and 33.33%, respectively. Conclusion: There were no significant differences between the diagnostic values of the two imaging modes used in the diagnosis of root fracture or in the presence of root canal restorations. In both modes, the most true-positive results were reported in the post space group.

• International Journal of Oral Biology
• /
• 제41권4호
• /
• pp.243-251
• /
• 2016

This study was undertaken to achieve a high bleaching efficacy with plasma, through longer application and reparative bleaching processes, by different shade evaluation methods. Extracted human teeth were divided into 6 groups (n=10). All teeth were treated in pairs. Low concentration of 15% carbamide peroxide (CP) was applied, with and without plasma, for 10, 20, and 30-min tooth bleaching, respectively. The bleaching procedure was repeated once daily for four days. The teeth were maintained in a moist environment provided by artificial saliva. The Vitapan Classical shade guide and Commission Internationale de L'Eclairage (CIELAB) color system were collectively used to measure the bleaching efficacy. Color evaluation was statistically analyzed using Student t-test and one-way analysis of variance (ANOVA) complemented by Tukey's test. Combining the plasma with 15% CP showed significantly greater color changes compared to bleaching without plasma (p<0.05). A high bleaching efficacy with plasma is proportional to the repetitive application and the treatment time. A 30-min application with plasma provided the best bleaching. Repetitive bleaching showed lower probability of color relapse of the bleached tooth. The color change by shade guide correlated with the changes in CIELAB color system. A value of 1 color change units (CCU) conversion factor for overall color change (${\Delta}E$) values comparisons was 3.724 values. The two measuring methods provide a more accurate correspondence of color change. The repetitive and longer application for tooth bleaching, combined with plasma, has a strong bleaching effect and produces whiter teeth.

• 대한치과보철학회지
• /
• 제14권1호
• /
• pp.17-21
• /
• 1976

The author studied the gingival responses to some dental cements in the gingival sulcus around artificial crowns. Abutment preparation for full veneer crown was performed in the canines of the two dogs. The location of cervical margins was about 0.5mm. below the gingival crest. Niranium metal crowns were constructed for the teeth, and cemented with zinc phosphate cement or polycarboxy late cement. In the experimental groups the retained cements in the gingival sulucus were not removed, and in the control groups the cements were removed completely after cementation. The dogs were sacrificed at 3 weeks and 5 weeks respectively after cementation. The gingival responses to these cements were examined histologically. The findings were as follows. 1. There was severe inflammation in the gingiva where the cements had been retained in the gingival sulcus around artificial crowns. 2. There was more severe inflammation in the gingiva which had contacted with zinc phosphate cement than in the gingiva with polycarboxylate cement. 3. There was mild inflammation in the gingiva around the margins of Niranium crowns. 4. The retained cement around the margin of restoration should be completely removed after cementation.

• Imaging Science in Dentistry
• /
• 제33권2호
• /
• pp.91-95
• /
• 2003

Purpose : To compare the diagnostic accuracy of proximal caries detection between Kodak Insight film and the Biomedisys CDX2000HQ digital (CCD) sensor. Materials and Methods: 156 proximal surfaces of extracted teeth, 78 of which had chemical artificial caries, were used in this study. Four observers interpreted the radiographs using a five-point confidence rating scale to record their diagnoses. The results were analyzed by receiver operating characteristic curves, ANOVA and Kappa values. Result: Analysis using receiver operating characteristic curves revealed the areas under each curve which indicated a diagnostic accuracy of 0.951 in Insight and 0.952 in CDX2000HQ digital sensor. ANOVA revealed no significant differences between the two images with respect to caries detection. Kappa values indicated that the mean intra-observer agreement was 0.85 and inter-observer agreement 0.71 in conventional radiography. In digital radiography, the mean intra-observer agreement was 0.84 and inter-observer agreement 0.72. Conclusion: The results suggest that no significant difference exists between the two modalities for artificial caries detection and that CDX2000HQ was as good as Insight film for this purpose.

• Restorative Dentistry and Endodontics
• /
• 제19권1호
• /
• pp.180-193
• /
• 1994

The purpose of this study was to observe the sealing ability and durability of All-Bond 2, Gluma Bonding System, Scotch bond 2 and Superbond D-liner which are dentin bonding agents used as desensitizing agents. The durability of the sealing ability of the materials were compared after 0, 140, 420, 840 tooth brushing strokes. 120 extracted teeth were divided into 5 groups and the agents were applied to the exposed dentin. No agents was applied on group I, the control group. Each specimen went through thermocycling from $5^{\circ}$ to $55^{\circ}C$, 200 times. Each group was devide into 4 subgroups and artificial tooth brushing strokes were done for 0, 140, 420, 840 times. Finally the specimens were stored in 0.5 % methylene blue solution for 24 hours in a incubator set at $37^{\circ}C$. The tooth were sectioned perpendicular to the long axis and the dye penetration ratio to the pulp was measured. The following results were obtained. 1. All four dentin bonding agents initially showed excellent sealing ability. 2. All-bond 2, Gluma Bonding System and Superbond D-liner showed durability of dentinal tubule sealing effect after 840 strokes(6-week) artificial tooth brushing. 3. Scotchbond 2 showed a significant decrease in sealing ability after 420 strokes(3-week) artificial tooth brushing. (P<0.05).

• The Journal of Advanced Prosthodontics
• /
• 제4권2호
• /
• pp.109-115
• /
• 2012

PURPOSE. The purpose of this clinical study was to evaluate the frequency and type of prosthetic complications in relation to type and properties of removable dentures and to investigate the influence of these complications and several data about the existing dentures on patient satisfaction. MATERIALS AND METHODS. Ninety nine patients (44 males and 55 females) wearing removable dentures have been included in the study. The complications of the patients were recorded; patient satisfaction was determined with a Visual Analog Scale (VAS) and the relationship of complications and patient satisfaction with several data about the dentures such as denture age, type of denture, centric relation and vertical dimension was investigated. Kruskal Wallis, Mann Whitney U and Chi square tests were used for statistical analyses. The results were evaluated statistically at a significance level of $P$ <.05. RESULTS. Need for addition of artificial teeth for dentures with correct centric relations was found to be significantly lower than dentures with wrong centric relations ($P$ <.01). Loss of retention, ulcerations and high vertical dimension affected the VAS chewing ability scores negatively and ulcerations affected the VAS phonation scores negatively ($P$ <.05). CONCLUSION. Considering the results of this study, it can be concluded that loss of retention, ulcerations and high vertical dimension caused patient dissatisfaction. Additionally, dentures with wrong centric relations caused need for addition of artificial teeth.

• 대한치과보철학회지
• /
• 제54권4호
• /
• pp.445-450
• /
• 2016

Piezography는 발음을 이용하여 채득된 보철 공간을 의미하며, 의치의 인공치와 연마면의 위치를 결정하는 참고점으로 사용하게 된다. 본 증례 대상은 67세 여성환자로, 새 의치 제작을 주소로 내원하였다. 기존 의치에서 2급 악간관계와 불량한 유지력을 확인할 수 있었으며, 안정적인 의치를 위해 piezography와 설측교합을 이용하기로 하였다. 통상적인 방법으로 인상 채득 후 주모형 상에서 상하악 기초상과 왁스 교합제를 제작하였고, 별도로 piezography를 위하여 하악에 추가적인 기초상을 하나 더 제작하였다. 이 추가 기초상에 실리콘 인상재를 적용 한 뒤 '시', '소', '메', '테', '데', '무' 여섯개의 발음으로 piezography를 채득하였다. 하악 인공치를 이 보철공간에 맞추어 배열한 뒤, 형태를 수정하여 설측 교합을 부여하였다. 그 결과, 환자는 새로운 의치에 기능적, 심미적으로 만족하였다.

• Restorative Dentistry and Endodontics
• /
• 제18권2호
• /
• pp.277-290
• /
• 1993

Dental caries is considered to be caused by demineralization by organic acid produced by microorganism. But the formation of subsurface lesion in initial caries make it diffcult to explain by simple demineralization. This study is carried out on the basis of thermodynamic concept proposed by Margolis and Moreno. The purpose of this study is to evaluate the effects of acid concentration and pH of lactate buffer system on the artificial caries lesion progress. 160 teeth without any crack, defect or opaque enamel were used and coated with nail varnish except the window ($2{\times}3$ mm). Under the constant degree of saturation(D.S.). The teeth were divided into 8 groups according to acid concentration(10mM, 25mM, 50mM, 100mM) and pH(4.3, 5.0, 6.0). Each group was immersed in buffer solution for 3, 6, 9, 18 days under controlled temperature($25^{\circ}C$). After cutting through the window and grinding, the specimens, 100-150 um in thickness, were imbibed in water or air and examined using polarilizing microscope. The depth of the surface and subsurface surface lesion were measured. 1. In the constant pH and D. S. value, the subsurface lesion progresses more rapidly as the concentration of lactic acid increases. (0.01, 0.025, 0.05, 0.1) 2. In the constant acid concentration and DS value, the subsurface lesion progresses more slowly as the pH increases. (4.3, 5.0, 5.5, 6.0) 3. The width of surface lesion seems to be constant independant of pH and acid concentration.

• Imaging Science in Dentistry
• /
• 제41권4호
• /
• pp.143-150
• /
• 2011

Purpose : The aim of this study was to compare the diagnostic accuracy of cone-beam computed tomography (CBCT) images and bitewing images in detection of secondary caries. Materials and Methods : One hundred and twenty proximal slots of Class II cavities were randomly prepared on human premolar and molar teeth, and restored with amalgam (n=60) and composite resin (n=60). Then, artificial secondary caries lesions were randomly created using round steel No. 4 bur. The teeth were radiographed with a conventional bitewing technique and two CBCT systems; Pax-500ECT and Promax 3D. All images were evaluated by five observers. The area under the receiver operating characteristic (ROC) curve ($A_z$) was used to evaluate the diagnostic accuracy. Significant difference was tested using the Friedman test (p value<0.05). Results : The mean $A_z$ values for bitewing, Pax-500ECT, and Promax 3D imaging systems were 0.882, 0.995, and 0.978, respectively. Significant differences were found between the two CBCT systems and film (p=0.007). For CBCT systems, the axial plane showed the greatest $A_z$ value. Conclusion : Based on the design of this study, CBCT images were better than bitewing radiographs in detection of secondary caries.