• 한국치위생학회지
• /
• 제12권3호
• /
• pp.485-493
• /
• 2012

Objectives : The purpose of this study is to provide basic data to develop health education program, by analyzing the relationship between the oral health behavior intention and self-efficacy in dental hygiene students. Methods : This research was based on self administrated survey conducted by 348 dental hygiene students. The survey was composed of five items of general characteristics, ten items of factor in self-efficacy and seven items of factor in oral health behavior intention. Results : According to general characteristics, students with high grades had higher oral health behavior intention(p<0.05) and students answered that the significance of oral health is very important had higher oral health behavior intention(p<0.05). The level of self-efficacy was separated by high-level(30%), medium-level(40%), and low-level (30%), and the higher self-efficacy was, the higher oral health behavior intention was. Conclusions : By improving dental hygiene student's self-efficacy, it was necessary to promote oral health behavior intention.

• 대한치과기공학회지
• /
• 제41권2호
• /
• pp.93-100
• /
• 2019

Purpose: This study is making a dog dental prosthesis using digital dental technology. The mechanical strength of the prosthetic material was observed in terms of compressive strength and fracture pattern. Methods: The experiment was performed using dog mandibular molars. The teeth were scanned and modeled. The specimens were made of zirconia, PMMA and Ni-Cr. The specimens were subjected to a vertical compression test with an artificial cancellous bone in UTM tester. Vertical compressive strength and fracture behavior of specimen were observed. Results: The result of observing the compressive load between specimen and artificial bone were $184.8{\pm}5.7N$ in the zirconia specimen, $185.6{\pm}8.9N$ in the PMMA specimen, and $184.4{\pm}4.0N$ in the Ni-Cr alloy specimen. Compression marks of artificial bones were observed. The fracture strength of specimen was observed. The fracture strength of the zirconia specimen was an average of 1,381.4N. The fracture strength of the PMMA specimen was an average of 572.2N. Conclusion: The crown made of three kinds(zirconia, PMMA, Ni-Cr alloy) of materials has the strength to chew about the artificial bone. zirconia and PMMA have vertical compressive strength applicable to medium dog dental prosthetic materials.

• 대한치과교정학회지
• /
• 제49권6호
• /
• pp.404-412
• /
• 2019

Objective: To assess shear bond strength and failure mode (Adhesive Remnant Index, ARI) of orthodontic brackets bonded to polymethylmethacrylate (PMMA) blocks for computer-aided design/manufacture (CAD/CAM) fabrication of temporary restorations, following substrate chemical or mechanical treatment. Methods: Two types of PMMA blocks were tested: $CAD-Temp^{(R)}$ (VITA) and $Telio^{(R)}$ CAD (Ivoclar-Vivadent). The substrate was roughened with 320-grit sandpaper, simulating a fine-grit diamond bur. Two universal adhesives, Scotchbond Universal Adhesive (SU) and Assure Plus (AP), and a conventional adhesive, Transbond XT Primer (XTP; control), were used in combination with Transbond XT Paste to bond the brackets. Six experimental groups were formed: (1) $CAD-Temp^{(R)}/SU$; (2) $CAD-Temp^{(R)}/AP$; (3) $CAD-Temp^{(R)}/XTP$; (4) $Telio^{(R)}$ CAD/SU; (5) $Telio^{(R)}$ CAD/AP; (6) $Telio^{(R)}$ CAD/XTP. Shear bond strength and ARI were assessed. On 1 extra block for each PMMA-based material surfaces were roughened with 180-grit sandpaper, simulating a normal/medium-grit ($100{\mu}m$) diamond bur, and brackets were bonded. Shear bond strengths and ARI scores were compared with those of groups 3, 6. Results: On $CAD-Temp^{(R)}$ significantly higher bracket bond strengths than on $Telio^{(R)}$ CAD were recorded. With XTP significantly lower levels of adhesion were reached than using SU or AP. Roughening with a coarser bur resulted in a significant increase in adhesion. Conclusions: Bracket bonding to CAD/CAM PMMA can be promoted by grinding the substrate with a normal/medium-grit bur or by coating the intact surface with universal adhesives. With appropriate pretreatments, bracket adhesion to CAD/CAM PMMA temporary restorations can be enhanced to clinically satisfactory levels.

• 대한소아치과학회지
• /
• 제50권3호
• /
• pp.347-359
• /
• 2023

본 연구는 탈구된 치아의 저장 매체로서 polydeoxyribonucleotide (PDRN)의 적합성을 평가하고자 하였다. HBSS와 10, 25, 50, 100 ㎍/mL 농도의 PDRN 용액과 수돗물에 저장된 인간 치주인대 세포의 생존율을 측정하기 위해 Cell Counting Kit-8 assay와 Live/Dead assay를 시행하였다. 또한, PDRN의 항염증 효과를 평가하기 위한 NO 검출 및 qRT-PCR 실험을 진행하였다. 100 ㎍/mL 농도의 PDRN 용액에 저장된 치주인대 세포의 생존율이 다른 용액보다 유의하게 높았다(p < 0.01). 또한, 100 ㎍/mL 농도의 PDRN 용액은 유의하게 NO의 생산을 줄였다(p < 0.0001). 그리고, HBSS 용액에 비하여 50 및 100 ㎍/mL 농도의 PDRN 용액에서 유의하게 tumor necrosis factor α, interleukin (IL)-4, IL-6, 그리고 IL-10의 발현이 낮았다(p < 0.01). 이 연구를 통해 PDRN은 치주인대 세포에 세포 보존 및 항염증 효과를 가진 것으로 밝혀졌다. 이 연구는 효과적인 탈구치 저장매체의 개발을 위한 향후 추가적인 실험의 기반이 될 수 있을 것이라 생각한다.

• 대한치과기공학회지
• /
• 제2권1호
• /
• pp.39-46
• /
• 1980

• 치위생과학회지
• /
• 제12권3호
• /
• pp.209-215
• /
• 2012

본 연구는 소목(C. sappan L.)으로부터 분리된 Brazilin이 S. mutans의 생장 및 배양 환경 에 미치는 영향을 측정하고 다음과 같은 결과를 얻었다. 1. Methanol에 의해 분리된 소목의 수율은 총 4.8%로 나타났으며, 여러 분획물 가운데 brazilin이 포함된 에틸아세테이트(EtOAc) 분획물에서 3.94%로 가장 높은 수율을 보였다. 2. 소목으로부터 분리된 brazilin의 S. mutans 생장에 대한 효과는 대조군이 24시간에서 0.816으로 최대 생장률을 보였으나, brazilin (0.3 mg/ml, 1 mg/ml, 3 mg/ml)을 투여한 배지는 32시간 만에 최대생장을 보였다. 3. S. mutans를 16시간 동안 배양한 후 배지 내 pH를 측정한 결과 대조군은 5.25이었으며, brazilin (0.3 mg/ml, 1mg/ml, 3 mg/ml)을 투여한 배지는 각각 pH 7.00, pH 7.01, pH 6.98로 유지하여 산 생성을 억제하였다. 4. S. mutans를 48시간 동안 배양한 후 배지 내 탄수화물 변화량을 측정한 결과 대조군보다 소목의 brazilin이 투여된 배지의 탄수화물의 소모량이 적었다. 5. S. mutans를 24 시간 동안 배양한 후 배지 내 단백질 변화량을 측정한 결과, 최대 생장량을 보인 24 시간에서 대조군은 2.46 mg/ml 이었으며, 소목의 brazilin이 투여된 배지는 2.54 mg/ml 이었다. 6. S. mutans의 다당류 생성에 미치는 효과는 대조군의 경우 배양 8 시간에 300 mg/100 ml을 생성하였으나, 소목의 brazilin이 투여된 배지에서는 200 mg/100 ml을 생성하였다. 이상의 결과를 볼 때, 소목의 EtOAc 분획에 존재하는 brazilin은 배지 내 S. mutans 균주의 생육을 억제하는 효과가 있어, 향후 구강 내 우식원성 세균의 억제물질로 활용을 제시한다.

• 대한치과기공학회지
• /
• 제23권1호
• /
• pp.75-83
• /
• 2001

This study was conducted to find antibacterial agent against growth of dental caries bacteria. St. mutans KDJ-50 from various medicinal plants of which safety was indetified. Medicinal plants used in this study was dried and grinded after purchased at Daegu yakryung sijang and Kyungsan jungang sijang. Medicinal plants extracted with 80% ethanol at boiling point for 3 hrs was used as antibacterial agent after freeze dried. This study was conducted to find antibacterial agent against growth of dental caries bacteria. St. mutans KDJ-50 from 32 medicinal plants of which safety was indetified. The result of using paper disc method. Caryophylli Flos. Coptidis Rhizoma. Phellodendri Cortex. Schizamdrae Fructs. Myristicae Semen, Crataegi Fructus and Acori Graminei Rhizoma was selected as antibacterial agent. The result of viable cell counting method. the antibacterial activity of Caryophylli Flos was highest among tested 7 medicinal plants followed by Phellodendri Cortex and Coptidis Rhizoma. The extinction effect of the St. mutans by Caryophylli Flos was shown with the addition of 0.5 (w/v) in the medium. The high antibacterial activity was acquired at high extraction temperature and long extraction temperature. The antibacterial activity of Caryophylli Flos was not effected by the concentration of ethanol.

• 대한치과의사협회지
• /
• 제20권3호통권154호
• /
• pp.233-237
• /
• 1982

A review of the literature was presented, illustrating the effect that gingivally retained orthodontic elastic bands have on the periodontal tissues. A case report was presented for treatment of mobile maxillary central incisors secondary to a subgingival elastic band. Following surgical removal of elastic band and periodontal debridement, the teeth were successfully retained with active orthodontic appliances. Until a harmless radiopaque medium can be safely incorporated into elastic bands, extreme caution in their use should be observed. Not only should all attempts be made to anchor the elastic bands to the clinical crown, but the patient should receive through instructions in their placement and removal.

• 대한치과기공학회지
• /
• 제11권1호
• /
• pp.89-93
• /
• 1989

The purpose of this study was to evaluate the effect of sprue length and casting pressure on the relative castability of the base metal alloys, commonly used to make porcelain metal restoration. Samples of total 30 were constucted and devided into 6 groups according to three variables (low, medium, high). The total number of complety cast squares were counted, verified and recorded. The results of this 1. main effect of casting pressure was statistically significant.(P<0.05). 2. main effect of sprue length was not statistically significant.

• 대한치과기공학회지
• /
• 제32권3호
• /
• pp.255-264
• /
• 2010

Purpose: This study was conducted to corroborate factors affecting dental technicians recognition states of their job consciousness. Methods: Self-administering questionnaires were distributed directly to some 200 registered female dental technicians in metropolis, small & medium-sized cities, farming and fishing villages of whom 153(76.5%) female dental technicians and female students responded in December, 2009. Information on recognition states of female dental technicians and female students in department of dental technology possible occupational mind and other general characteristics was gathered. Analysis of data was processed by use of X2-test and multiple regression analysis. Results: The recognition states of occupational satisfaction were higher in female students than female dental technicians(p<.05). They were observed that between respondents with more than five years of work and less than five years of career(p<.05). Statistically significant differences were observed in recognition values of female dental technicians occupational satisfaction between high and low groups of internal characteristic of their position and all ceramic part(p<.05). Conclusion: For woman dental technicians, the most predictive variables for recognition values of occupational satisfaction were an age, between groups, which of part and career(p<.05). Finally, this result suggests the facts that in order to achieve self-realization through the work experience, women herself should get rid of the dichotomous diagram and should change the consciousness of traditional role normals.