• Restorative Dentistry and Endodontics
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• 제46권1호
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• pp.6.1-6.10
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• 2021

Objectives: The aim of this study was to evaluate the corrosion resistance of heat-treated (Reciproc and WaveOne) and non-heat-treated (ProTaper and Mtwo) superelastic nickel-titanium endodontic files when immersed in a 5.25% sodium hypochlorite solution. Materials and Methods: Anodic polarization curves were obtained with potential sweeps that began at the open circuit potential or corrosion potential (E_corr). The pitting potential (E_pit) was identified on the anodic polarization curve as the potential at which a sudden increase in current was observed. The micromorphology of the 28 tested files was analyzed before and after the electrochemical assay using scanning electron microscope (SEM). The data were analyzed using 1-way analysis of variance with the post hoc Bonferroni test (for E_corr) and the Student t-test for independent samples (for E_pit). Results: The mean E_corr values were 0.506 V for ProTaper, 0.348 V for Mtwo, 0.542 V for Reciproc, and 0.321 V for WaveOne files. Only WaveOne and Protaper files exhibited pitting corrosion, with E_pit values of 0.879 V and 0.904 V, respectively. On the SEM images of the ProTaper and WaveOne files, cavities suggestive of pitting corrosion were detected. Conclusions: Signs of corrosion were observed in both heat-treated and non-heat-treated files. Of the evaluated files, WaveOne (a heat-treated file) and ProTaper (a non-heat-treated file) exhibited the lowest corrosion resistance.

• Restorative Dentistry and Endodontics
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• 제46권4호
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• pp.48.1-48.10
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• 2021

Objectives: This study aimed to evaluate the effects on bone repair of different concentrations of mineral trioxide aggregate (MTA) added to AH Plus. Materials and Methods: Bone tissue reactions were evaluated in 30 rats (Rattus norvegicus) after 7 and 30 days. In the AH + MTA10, AH + MTA20, and AH + MTA30 groups, defects in the tibiae were filled with AH Plus with MTA in proportions of 10%, 20% and 30%, respectively; in the MTA-FILL group, MTA Fillapex was used; and in the control group, no sealer was used. The samples were histologically analyzed to assess bone union and maturation. The Kruskal-Wallis and Mann-Whitney tests were performed for multiple pairwise comparisons (p ≤ 0.05). Results: At the 7-day time point, AH + MTA10 was superior to MTA-FILL with respect to bone union, and AH + MTA20 was superior to MTA-FILL with respect to bone maturity (p < 0.05). At the 30-day time point, both the AH + MTA10 and AH + MTA20 experimental sealers were superior not only to MTA-FILL, but also to AH + MTA30 with respect to both parameters (p < 0.05). The results of the AH + MTA10 and AH + MTA20 groups were superior to those of the control group for both parameters and experimental time points (p < 0.05). Conclusions: The results suggest the potential benefit of using a combination of these materials in situations requiring bone repair.

• Restorative Dentistry and Endodontics
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• 제45권4호
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• pp.47.1-47.11
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• 2020

Objectives: The aim of this study was to assess the physicochemical properties, cytotoxicity and penetration into dentinal tubules of ChlorCid^TM Surf (3% sodium hypochlorite [NaOCl] with surfactant) in comparison to ChlorCid^TM (3% NaOCl without surfactant). Materials and Methods: The physicochemical properties evaluated were pH, surface tension, free available chlorine (FAC) and contact angle. Cytotoxicity was evaluated in L929 fibroblasts exposed to the solutions by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and neutral red assays. Assessment of penetration into dentinal tubules was performed by staining single-rooted permanent human teeth with crystal violet (n = 9), which were irrigated with the solutions and analyzed in cervical, middle and apical segments. Data were analyzed by one-way analysis of variance (ANOVA) and Tukey's post-test, 2-way ANOVA and Bonferroni's post-test or t-test (α = 0.05). Results: ChlorCid^TM Surf and ChlorCid^TM FAC values were close to those indicated by the manufacturer. ChlorCid^TM Surf showed lower surface tension and contact angle on dentin, and higher pH than ChlorCid^TM (p < 0.05). The penetration of ChlorCid^TM Surf was higher in cervical and middle segments, compared with ChlorCid^TM (p < 0.05). There was no difference in irrigant cytotoxicity (p > 0.05). Conclusions: ChlorCid^TM Surf showed lower surface tension, lower contact angle on root canal dentin, higher penetration into dentinal tubules and more alkaline pH, compared with ChlorCid^TM. However, both solutions showed similar cytotoxicity and FAC content.

• Restorative Dentistry and Endodontics
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• 제47권3호
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• pp.34.1-34.12
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• 2022

Objectives: This study aimed to evaluate the success rate of endodontic treatments performed by undergraduate students and the factors associated with the outcome. Materials and Methods: A follow-up of 3 to 8 years after root canal filling was carried out in 91 patients. At the follow-up visits, medical and dental history questionnaires were applied along with clinical and radiographic examinations. Data collected in the clinical exam included: the presence of pain, swelling, sinus tract, mobility, tenderness to palpation and percussion, periodontal probing profile, and type/quality of coronal restoration. Postoperative and follow-up radiographs were digitalized and analyzed by 2 trained and calibrated examiners to assess periapical healing. The treatment outcome was based on strict clinical and radiographic criteria and classified as success (absence of any clinical and radiographic sign of apical periodontitis) or failure (other combination). Logistic regression was used to investigate the impact of clinical and radiographic variables on endodontic treatment outcomes at a 5% significance level. Results: The success rate of endodontic treatments was 60.7%. The only risk factor significantly associated with failure was the presence of a periapical lesion on the postoperative radiograph (odds ratio, 3.35; 95% confidence interval, 1.17-9.54). Conclusions: The success rate of endodontic treatments performed by undergraduate students was low and was jeopardized by the presence of a periapical lesion on the postoperative radiograph.

• Restorative Dentistry and Endodontics
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• 제47권3호
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• pp.27.1-27.14
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• 2022

Objectives: This systematic review and meta-analysis aimed to assess the association of cigarette smoking with the prevalence of post-endodontic apical periodontitis in humans. Materials and Methods: We searched through PubMed/Medline, Web of Science, and Scopus from inception to December 2020. Risk of bias was performed by using the Newcastle-Ottawa Scale for cross-sectional, cohort, and case-control studies. We performed the statistical analysis in Review Manager 5.3 (RevMan 5.3). Results: 6 studies met the inclusion criteria for qualitative and quantitative synthesis. Statistical analysis of these studies suggests that there were no differences in the prevalence of post endodontic apical periodontitis (AP) when comparing non-smokers vs smoker subjects regarding patients (odds ratio [OR], 0.68; 95% confidence interval [CI], 0.31-1.49; I2 = 58%) and teeth (OR, 1.71; 95% CI, 0.99-2.93; I2 = 72%). Conclusions: Our findings suggest that there was no association between cigarette smoking and post-endodontic apical periodontitis, as we did not find statistical differences in the prevalence of post-endodontic AP when comparing non-smokers vs smoker subjects. Therefore, smoking should not be considered a risk factor associated with endodontic failure.

• Restorative Dentistry and Endodontics
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• 제48권3호
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• pp.25.1-25.13
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• 2023

Objectives: The purpose of this study was to evaluate the influence of endodontic access cavities design on the removal of calcium hydroxide medication of the apical third of mandibular incisor root canal walls and dentinal tubules with different cleaning protocols: EDDY sonic activation, Er,Cr:YSGG laser-activated irrigation, or conventional irrigation with IrriFlex. Materials and Methods: Seventy-eight extracted human mandibular incisors were assigned to 6 experimental groups (n = 13) according to the endodontic access cavity and cleaning protocol for calcium hydroxide removal: traditional access cavity (TradAC)/EDDY; ultraconservative access cavity performed in the incisal edge (UltraAC.Inc)/EDDY; TradAC/Er,Cr:YSGG; UltraAC. Inc/Er,Cr:YSGG; TradAC/IrriFlex; or UltraAC.Inc/IrriFlex. Confocal laser scanning microscopy images were used to measure the non-penetration percentage, maximum residual calcium hydroxide penetration depth, and penetration area at 2 and 4 mm from the apex. Data were statistically analyzed using Shapiro-Wilk and WRS2 package for 2-way comparison of non-normally distributed parameters (depth of penetration, area of penetration, and percentage of non-penetration) according to cavity and cleaning protocol with the significance level set at 5%. Results: The effect of cavity and cleaning protocol interactions on penetration depth, penetration area and non-penetration percentage was not found statistically significant at 2 and 4 mm levels (p > 0.05). Conclusions: The present study demonstrated that TradAC or UltraAC.Inc preparations with different cleaning protocols in extracted mandibular incisors did not influence the remaining calcium hydroxide at 2 and 4 mm from the apex.

• 대한심미치과학회지
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• 제32권2호
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• pp.36-45
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• 2023

심미적인 전치부의 모습은 자연스럽고 건강한 미소를 위한 필수요건이며 대인관계의 자신감을 위해서도 중요한 요소이다. 전치부의 총생이=나 전돌이 존재하는 경우 단기간에 해결하기 위해 근관치료 및 과도한 치아삭제가 요구되는 경우가 많다. 하지만 이런 술식은 지속가능한 심미적 결과를 만들기 어렵다. 이런 경우 교정치료가 병행되어야만 수복이 필요한 치아들도 잔존 치질을 최대한 보존할 수 있을 것이다. 중장년층 환자들의 경우 교정 치료의 필요성을 절감하면서도 사회적 시선을 의식하여 브라켓을 이용한 전통적 방식의 교정치료 방법을 주저하는 경우가 많다. 이런 경우 투명교정장치는 좋은 선택지가 될 수 있다. 이에 투명교정만으로 심미적 요구를 해결한 증례와, 투명교정을 동반한 새로운 수복치료를 통해 만족스러운 결과를 얻은 다른 증례를 보고한다.

• Restorative Dentistry and Endodontics
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• 제31권2호
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• pp.86-95
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• 2006

본 연구는 치성 동통을 보이는 치아의 수산화칼슘의 사용 여부에 따른 동통 감소 효과를 판단하고자 시행하였다. 2003년 12월부터 2004년 9월 사이에 경희대학교 치과대학 부속 치과병원 치과보존과에 치성 동통으로 내원한 환자 213명으로부터 근관형성을 시행한 237개의 치아를 대상으로 환자의 성별 및 연령 치료부위, 재근관 치료의 여부, 치수의 상태, 술전 치아 상태와 술전 동통의 정도를 기록하였다. 수산화칼슘을 적용하지 않은 군 (1군)과 수산화칼슘을 적용한 군 (2군)으로 분류하였다. 환자들에게 설문지를 배분하여 다음 내원시 치료 후4시간, 2일 및 7일에 술후 동통의 발생 여부와 동통의 정도를 기록하도록 하였다. 수집한 자료들은 Chi-square analysis (p < 0.05)를 사용하여 비교, 분석한 결과 근관내 약제로써 수산화칼슘은 술후 동통을 예방하거나 감소시키는 효과를 가지고 있지 않다는 것을 알 수 있었다.

• 대한소아치과학회지
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• 제36권2호
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• pp.305-309
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• 2009

치외치(Dens Evaginatus)란 교합면에 법랑질이 원추형으로 돌출되어 결절을 형성한 치아로 치아발육중 법랑기의 내측법랑상피가 외부로 과증식되거나 치수 간엽조직이 국소적으로 과증식되어 나타난다. 결절은 교합력이나 저작에 의해 파절 또는 마모되기 쉬우며 따라서 이로 인하여 치수노출에 의한 감염이 야기될 수 있다. 치외치는 예방목적으로 결절을 주기적으로 조금씩 갈아주어 2차 상아질을 유도하거나 전색제등으로 결절주위를 보강하여 자연마모를 유도할 수 있다. 반면 이미 증상을 보인 치아에 대해서는 근관치료를 시행하거나, 미완성치근인 경우 치근단유도술(Apexogenesis)이나 치근단형성술(Apexification)을 시행한다. 치근단유도술이란 생활력을 가진 미성숙 영구치의 손상, 또는 치아우식에 의한 치수노출 시 치수절단술을 시행하여 치수의 생활력을 유지시켜 정상적인 치근으로 발육하도록 유도하는 술식을 말한다. 주로 수산화칼슘을 이용한 통상의 치수절단술이 이용되고 이후 계속적인 치근형성 확인을 위해 주기적 방사선검사가 요구된다. 본 증례는 하악 좌측 제2소구치 부위의 동통을 주소로 내원한 한자에 대한 것으로, 임상검사결과 양측 소구치 부위에 치외치를 확인하게 되었다. 이에 수산화칼슘을 통한 치근단유도술을 시도하였고, 3년간 주기적 내원을 통해 치료한 결과 치근의 근심면의 비정형적 발달을 보였다. 현재 이 치아는 임상증상과 방사선 사진을 통해 확인한 결과 특이한 염증소견 없는 예후를 보이고 있기에 보고하는 바이다.

• Restorative Dentistry and Endodontics
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• 제24권1호
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• pp.40-48
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• 1999

This study was designed to examine the specificities of the designed primers for F. nucleatum and F. necrophorum and to compare the PCR results using clinical samples with those of the anaerobic culture method. F. nucleatum and F. necrophorum spp. are frequently isolated in infected root canals, and they are related to periapical diseases. F. nucleatum(VPI 10197) and F. necrophorum(ATCC 25286) were used as references for PCR reaction, and thirty five teeth with one canal and periapical lesion were used. The samples were cultured anaerobically and identified using Rapid ID 32A(BioMerieux Vitek, Inc., France) as biochemical battery. In the GenBank database, species-specific PCR primers(nuc1/nuc2 primers for F. nucleatum and nec1/nec2 primers for F. necrophorum) were designed from the 16S ribosomal DNA(rDNA) sequences of F. nucleatum(accession number M58683) and F. necrophorum(accession number AF044948). PCR procedures of F. nucleatum(VPI 10197) and F. necrophorum (ATCC 25286) were simulated on a computer software. Amplify(v.1.2${\beta}$ for Macintosh). 820 bps and 817 bps of nucleotides were expected, respectively. Using extracted DNAs with QiaAmp tissue kit(Qiagen co., Germany), PCR was done. The results were as follows : 1. The nuc1/nuc2 primers produced an amplicon of 820 bps and the nec1/nec2 primers produced an amplicon of 817 bps. 2. The nuc1/nuc2 primers and the nec1/nec2 primers were specific and did not react with species other than the designated ones(i.e. nuc1/nuc2 primers did not produce amplicons for F. necrophorum, and vice versa.). And the PCR products of Porphyromonas endodontalis(ATCC 35406), Porphyromonas gingivalis(ATCC 33277), Prevotella intermedia(ATCC 25611), and Prevotella nigrescens(ATCC 33563), frequently isolated in infected root canals and periapical lesions, were not amplified by the primers specific for Fusobacterium nucleatum and Fusobacterium necrophorum. 3. This method utilizing PCR could detect F. nucleatum and F. necrophorum in clinical samples, while anaerobic culture method could detect neither.