• Restorative Dentistry and Endodontics
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• 제47권3호
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• pp.29.1-29.10
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• 2022

Objectives: This study aimed to investigate the anti-erosive/abrasive effect of resin infiltration of previous deproteinized dentin. Materials and Methods: Dentin slabs were randomly assigned to 3 groups (n = 15): Control (no deproteinization; no resin infiltrant applied), RI (no deproteinization; resin infiltrant applied), and DRI (deproteinization; resin infiltrant applied). After undergoing the assigned treatment, all slabs were subjected to an in vitro cycling model for 5 days. The specimens were immersed in citric acid (0.05 M, pH = 3.75; 60 seconds; 3 times/day) and brushed (150 strokes). Between the challenges, the specimens were exposed to a remineralizing solution (60 minutes). The morphological alterations were analyzed by mechanical profilometry (㎛) and scanning electron microscopy (SEM). Data were submitted to one-way analysis of variance (ANOVA) and Tukey tests (p < 0.05). Results: Control and RI groups presented mineral wear and did not significantly differ from each other (p = 0.063). DRI maintained a protective layer preserving the dentin (p < 0.001). After erosive/abrasive cycles, it was observed that in group RI, only 25% of the slabs partially evidenced the presence of the infiltrating, while, in the DRI group, 80% of the slabs presented the treated surface entirely covered by a resin-component layer protecting the dentin surface as observed in SEM images. Conclusions: The removal of the organic content allows the resin infiltrant to efficiently protect the dentin surface against erosive/abrasive lesions.

• Restorative Dentistry and Endodontics
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• 제48권3호
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• pp.29.1-29.8
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• 2023

Objectives: This study tested the hypothesis that cryotherapy duration influences lipopolysaccharide (LPS)-induced inflammation in a rat model. Materials and Methods: Six Wistar rats (Rattus norvegicus albinus) were used. Five sites were selected per animal and divided into 5 groups: a negative control group (NC), 2 positive control groups (PC1 and PC2), and 2 experimental groups (E1 and E2). Cryotherapy was applied for 1 minute (E1) or 5 minutes (E2). An acute inflammatory response was induced in the PC and E groups via subcutaneous administration of 0.5 mL/kg. In the PC2 group, a catheter was inserted without additional treatment. For the E1 and E2 groups, 2.5℃ saline solution was administered through the implanted catheters for 1 and 5 minutes, respectively. The rats were sacrificed, and samples were obtained and processed for histological analysis, specifically examining the presence of polymorphonuclear neutrophils and hemorrhage. The χ² test was used to compare the presence of acute inflammation across groups. Dependent variables were compared using the linear-by-linear association test. Results: Inflammation and hemorrhage varied significantly among the groups (p = 0.001). A significantly higher degree of acute inflammation was detected (p = 0.0002) in the PC and E1 samples than in the E2 group, in which cryotherapy was administered for 5 minutes. The PC and E1 groups also exhibited significantly greater numbers of neutrophils (p = 0.007), which were essentially absent in both the NC and E2 groups. Conclusions: Cryotherapy administration for 5 minutes reduced the acute inflammation associated with LPS and catheter implantation.

• Imaging Science in Dentistry
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• 제54권2호
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• pp.159-169
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• 2024

Purpose: The aim of this study was to evaluate the influence of different cone-beam computed tomography (CBCT) acquisition protocols on reducing the effective radiation dose while maintaining image quality. Materials and Methods: The effective dose emitted by a CBCT device was calculated using thermoluminescent dosimeters placed in a Rando Alderson phantom. Image quality was assessed by 3 experienced evaluators. The relationship between image quality and confidence was evaluated using the Fisher exact test, and the agreement among raters was assessed using the kappa test. Multiple linear regression analysis was performed to investigate whether the technical parameters could predict the effective dose. P-values<0.05 were considered to indicate statistical significance. Results: The optimized protocol (3 mA, 99 kVp, and 450 projection images) demonstrated good image quality and a lower effective dose for radiation-sensitive organs. Image quality and confidence had consistent values for all structures (P<0.05). Multiple linear regression analysis resulted in a statistically significant model. The milliamperage (b=0.504; t=3.406; P=0.027), kilovoltage peak (b=0.589; t=3.979; P=0.016) and number of projection images (b=0.557; t=3.762; P=0.020) were predictors of the effective dose. Conclusion: Optimized CBCT acquisition protocols can significantly reduce the effective radiation dose while maintaining acceptable image quality by adjusting the milliamperage and projection images.

• Journal of Preventive Medicine and Public Health
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• 제57권1호
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• pp.65-72
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• 2024

Objectives: Protecting people against financial hardship caused by illness stands as a fundamental obligation within healthcare systems and constitutes a pivotal component in achieving universal health coverage. The objective of this study was to analyze the prevalence and determinants of catastrophic health expenditures (CHE) in Iran, over the period of 2013 to 2019. Methods: Data were obtained from 7 annual national surveys conducted between 2013 and 2019 on the income and expenditures of Iranian households. The prevalence of CHE was determined using a threshold of 40% of household capacity to pay for healthcare. A binary logistic regression model was used to identify the determinants influencing CHE. Results: The prevalence of CHE increased from 3.60% in 2013 to 3.95% in 2019. In all the years analyzed, the extent of CHE occurrence among rural populations exceeded that of urban populations. Living in an urban area, having a higher wealth index, possessing health insurance coverage, and having employed family members, an employed household head, and a literate household head are all associated with a reduced likelihood of CHE (p<0.05). Conversely, the use of dental, outpatient, and inpatient care, and the presence of elderly members in the household, are associated with an increased probability of facing CHE (p<0.05). Conclusions: Throughout the study period, CHE consistently exceeded the 1% threshold designated in the national development plan. Continuous monitoring of CHE and its determinants at both household and health system levels is essential for the implementation of effective strategies aimed at enhancing financial protection.

• The Journal of Advanced Prosthodontics
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• 제16권4호
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• pp.201-211
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• 2024

PURPOSE. The aim of this prospective clinical study was to compare the influence of palatal vault forms on accuracy and speed of intraoral (IO) scans in completely edentulous cases. MATERIALS AND METHODS. Based on the palatal vault form, participants were divided into three equal groups (n = 10 each); Class I: moderate; Class II: deep; Class III: flat palatal vault. A reference model was created for each patient using polyvinylsiloxane impression material. The poured models were digitized using an extraoral scanner. The resultant data were imported as a solid CAD file into 3D analysis software (GOM Inspect 2018; Gom GmbH, Braunschweig, Germany) and aligned using the software's coordinate system to determine its X, Y, and Z axes. Five digital impressions (DIs) of maxilla were captured for each patient using an intraoral scanner (TRIOS; 3Shape A/S, Copenhagen, Denmark) and the resultant Standard Tessellation Language (STL) scan files served as test models. Trueness was evaluated by calculating arithmetic mean deviation (AMD) of the vault area between reference and test files while precision was evaluated by calculating AMD between captured scans to measure repeatability of scan acquisition. The scan time taken for each participant was also recorded. RESULTS. There was no significant difference in trueness and precision among the groups (P = .806 and .950, respectively). Average scan time for Class I and III palatal vaults was 1 min 13 seconds and 1 min 37 seconds, respectively, while class II deep palatal vaults showed the highest scan time of 5 mins. CONCLUSION. Palatal vault form in edentulous cases has an influence on scan time. However, it does not have a substantial impact on the accuracy of the acquired scans.

• Restorative Dentistry and Endodontics
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• 제49권3호
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• pp.30.1-30.12
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• 2024

Objectives: The aim of the current study was to evaluate the effect of polishing systems and surface sealant on the color stability and whiteness index of single-shade resin composites after staining and bleaching. Materials and Methods: Three single-shade (Omnichroma, Charisma Diamond One, Zenchroma) and one multi-shade (Filtek Z250) materials were tested. From each resin composite, 40 specimens were prepared. The specimens were divided into 4 subgroups (n = 10) according to the surface treatments: 1-step polishing, 1-step + Biscover LV, 2-step polishing, and 2-step polishing + Biscover LV. Color differences (ΔE₀₀) were calculated after being immersed in the coffee solution for 12 days. After the staining, the specimens were immersed in a whitening mouthrinse (Crest-3D White) for 12 hours. Whiteness index differences (ΔWI_D = WI_D after staining - WI_D after bleaching) values were recorded. The generalized linear model was used for analysis (p< 0.05). Results: The lowest and highest ΔE₀₀ values were found for Zenchroma and Charisma Diamond One respectively. Sealed groups indicated higher ΔE₀₀ values than nonsealed groups with significant differences (p = 0.008). The lowest and highest ΔWI_D values were found for Zenchroma and Charisma Diamond One respectively. Sealed groups indicated lower ΔWI_D values than nonsealed groups with significant differences (p = 0.022). Conclusions: The use of surface sealant increased the discoloration and showed less whiteness change in resin materials. When the 1-step was compared with the 2-step polishing, the effects on the color stability and whiteness index values of the resin materials were similar.

• 대한치과교정학회지
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• 제33권6호
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• pp.485-497
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• 2003

악안면 구조의 형태와 기능은 대개 유전자 정보에 의해 결정된다. 분자생물학의 발달로 인해 정상 성장과 형태 형성에 중요한 유전자에 대한 정보가 밝혀지고 있고 이는 현대 두개안면 생물학의 근간이 되고 있다. 밝혀진 사실들 중 주목할만한 것은 섬유아세포 성장인자2 (FGFR2)에 서 의 특이한 돌연변이 가 어 퍼트 증후군 (Apert syndrome) 의 발생과 관련이 있다는 것이다. 어퍼트 증후군은 두개 관상봉합의 조기 유합과 사지의 기형으로 특징지워진다. 그 중 특히 두개골 유합증의 병인과 형성기전을 연구하기 위해 본 연구에서 유전자 변환기법을 시도하여 어퍼트 증후군의 유발인자로 알려진 FGFR2에 서 의 단일 아미노산 치 환 돌연변이를 재연한 인위 유전자구조물을 제작하고 이를 미 세주입법으로 쥐의수정란에 삽입하여 형질변환 쥐를 제작하였다. 본 연구에서는 전체 조직이 아닌 골조직에서 특이하게 활성화되는 전사촉진자(promoter, 제 I형 교원질 유전자의 전사촉진자)를 이용하여 골조직에서만 돌연변이 유전자의 발현을 재현함으로써 이 시도가 쥐에서 두개골유합증을 유발하는지 검증하고자 하였다. 초기 표현형 분석을 통해 어퍼트 환자에서 기대되는 두개골 유합증을 확인하였다. 또한 본 연구에서 삽입된 변환유전자가 원활히 돌연변이 단백질을 생산하고 기능의 증가를 보임을 확인하였다. 이러한 동물 모델을 이용함으로써 이제 정상적 혹은 비정상적 두개골 및 봉합 발육에서의 FGFR2의 역할을 연구하는 것이 가능하리라 사료된다

• 치위생과학회지
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• 제14권2호
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• pp.158-166
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• 2014

본 연구는 남자 고등학생들의 스트레스와 구강건강의 중요성 및 주관적 구강건강상태 인식, 칫솔질 횟수에 따른 스트레스와 구강건강관련 삶의 질에 대한 연관성을 파악하여 고등학생들에 대한 실질적인 구강보건교육 필요성을 강조하며 청소년기의 구강위생관리가 올바르게 이루어져 성인 및 노인기까지 구강건강이 유지 증진되어 전반적인 삶의 질이 향상될 수 있는 기초자료를 제공하고자 한다. 2013년 5월부터 7월까지 충남에 위치한 2개 고등학교 1, 2학년을 대상으로 편의표본추출법에 의한 자기기입식으로 설문조사를 실시하였다. PASW Statistics 18.0과 AMOS 5.0 프로그램을 이용하여 다음과 같은 결과를 얻었다. 잠재변수 스트레스가 하위 5가지 영역의 스트레스와 구강건강관련 삶의 질과의 관련성을 분석결과 모두 유의한 것으로(p<0.001)로 나타났으며, 스트레스가 구강건강관련 삶의 질에 주는 영향력은 구강건강의 중요성 인식에 따라 구강건강이 중요하지 않다고 인식할 때보다(-0.38, p<0.001), 중요하다고 인식할 때(-0.32, p<0.001) 구강건강관련 삶의 질이 높은 것으로 나타나 스트레스의 영향이 낮은 것을 알 수 있으며, 주관적 구강건강 인식에서 또한 스스로 구강건강이 좋다고 인식할 때 스트레스의 영향력이-0.14 (p<0.05)로 낮게 나타나 구강건강관련 삶의 질이 높은 것으로 나타났다. 구강건강관리 행태와의 관련성에서는 하루 칫솔질 횟수가 1회로 낮을 때 스트레스가 구강건강의 삶의 질에 주는 영향력이 -0.69 (p<0.001)로 매우 높아 구강건강관련 삶의 질에도 매우 부정적인 영향을 주었다. 이상의 결과를 바탕으로 모델의 적합도 검정결과 GFI, AGFI, CFI, NFI에서 모두 0.9 이상을 보였으며, RMR과 RMSEA 값이 모두 0.1보다 작은 값이 추정되어 양호한 모형이다. 본 연구결과 스트레스와 구강건강관련 삶의 질은 연관성이 있다고 볼 수 있다. 또한 학생들의 구강건강 중요성 인식과 주관적 구강건강 인식도는 구강건강관련 삶의 질과 연관성이 있음을 확인되었고, 구강위생 관리 행태 중 칫솔질 횟수와도 연관성이 나타났다. 그러므로 본인의 구강건강을 스스로 책임져야 할 시기인 고등학생들이 구강건강을 위하여 바람직한 인식과 습관 형성을 위한 실질적이고 체계적인 구강보건교육이 시행되야 할 것이다.

• 대한치과보철학회지
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• 제33권4호
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• pp.753-768
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• 1995

For accurate impression taking of dental patient and esthetic denture treatment of ednetulous patient, measuring between intraoral anatomic landmarks is useful.In this study the subjects selected at a random were two-jundred forty persons with a mean age 22.5(range 21-24) and were taken impression of by irreversible hydrocolloid impression material(Alginate). On the study model made by dental stone, each individual tray was made and final impresion was taken by border moilding. On final model measurings were performed with 3-dimensional measuring device and the values were analyzed by t-test The results is following : ABOUT THE MEASURED VALUES. 1. The width between maxillary right and left canine cusp tip was average 36.44mm(s.d. 2.48), man 36.67mm, woman 35.83mm(p<0.05). 2. The width between labial height of contour of maxillary right and left canine was average 40.08mm(s.d. 2.42), man 40.29mm, woman 39.52mm(p<0.05). 3. The width between mesio-lingual cusps of maxillary first molar was average 43.14mm(s.d. 3.33), man 43.56mm, woman 42.05mm(p<0.05). 4. The width between buccal alveolar ridge on axis of mesiolingual cusp of right and left maxillary first molar was average 64.89mm(s.d. 3.88), man 65.58mm, woman 62.92mm(p<0.05). 5. The width between buccal alveolar ridge on axis of mesiolingual cusp of right and left maxillary second molar was average 68.58mm(s.d. 3.91), man 69.29mm, woman 66.30mm (p<0.05). 6. The width between right and left hamular notch was average 49.80mm(s.d. 3.96), man 50.70mm, woman 48.20mm(p<0.05). 7. The length from labial heigth of contour of maxillary central incisor to center of incisive papilla was average 9.52mm(s.d. 1.18), man 9.46mm, woman 9.63mm(p>0.05). 8. The length from labial heigth of contour of maxillary central incisor to palatine fovea was average 53.27mm(s.d. 2.93), man 53.93mm, woman 52.08mm(p<0.05). 9. The center of incisive papilla ws located posterior to intercanine line at 0.40mm(s.d. 1.16), man 0.51mm, woman 0.11mm(p<0.05). 10. The height from incisal edge of maxillary central incisor to the labial vestibule was average 21.84mm(s.d. 1.38), man 22.01mm, woman 21.00mm(p<0.05). 11. The height from mesiolingual cusp of maxillary first molar to buccalvestible was average 17.45mm(s.d. 1.42), man 17.56mm, woman 17.08mm(p>0.05). 12. The height from hamular notch to standard occlusal plane was average 6.84mm(s.d. 1.06), man 6.91mm, woman 6.70mm(p>0.05). 13. The height from the deepest point of palatal vault to standard occlsalplane was average 19.95 mm(s.d. 2.03), man 20.19mm, woman 19.12mm(p<0.05). ABOUT THE ARCH FORM 1. The arch form was able to classify into four typr by the rate of the measured values. Each arch form distribution was that the 1 group had 32.46% the 2 group 2.19%, the 3 group 52.83%, the 4 group 12.72%. The sexual composition was that in 1 group man had 73.5%, woman 26.5%, in 2 group man had 40.0%, woman 60.0%, in 3 group man had 83.3%, woman 16.7%, and in 4 group man had 55.17%, woman 44.83%. 2. When canine cusp tip was marked as point O, the intersection point between labial height of contour of maxillary central incisor and intermaxillary suture as point A, height of contour of maxillary second molar buccal alveolar ridge as B point, ${\angle}$AOB was measured $133.8^{\circ}$for the 1 group, $133.0^{\circ}$for the 2 group, $132.3^{\circ}$for the 3 group, $128.9^{\circ}$for the 4 group.

• 한국방사선학회논문지
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• 제5권5호
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• pp.237-244
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• 2011

일반적으로 저 에너지 방사선 조사로 검사하게 되는 치과 영역에서는 투과력이 약해 인체에 흡수되는 양이 많다. 치과 영역에서 방사선검사 시 부득이하게 방사선 노출을 받게 되는 방사선 작업종사자나 환자의 보호자가 위치와 거리에 따른 방사선 피폭 선량의 감소 방안을 알아보고자 한다. 진단용 발생장치인 GX-770, CRANEX TOME CEPH와 조사선량 측정기인 Ion chamber model 2026c, Reader기 20X6-1800을 사용하여 구강내 검사와 구강외 검사의 각각 검사실과 조정실에서의 관전압의 변화, 관전류와 조사시간의 변화, 조사방향의 변화에 따라 선량을 측정하였다. 그 결과 최고선량이 검사실 안에서는 평균 702.8 ${\mu}R$으로 측정 되었으며, 조정실 안에서 측정하였을 경우 20 ${\mu}R$이하의 낮은 선량을 보였으며, 120cm 거리에서 후방검사보다 측방검사가 낮은 선량으로 나타났다. 방사선검사시 위치와 거리에 따른 조사선량을 비교 분석하여, 적절한 거리 확보와 조사되는 중심방사선을 기준으로 측방($90{\sim}135^{\circ}$)에 위치함으로써 방사선 방어에 도움을 줄 것이며, 차폐문을 이용하여 방사선 피폭으로부터 감소 효과를 볼 수 있을 것이다.