• Restorative Dentistry and Endodontics
• /
• 제45권2호
• /
• pp.14.1-14.7
• /
• 2020

Objective: The aim of this study was to perform a comparative evaluation of the effectiveness of ultrasonic tips versus the Terauchi file retrieval kit (TFRK) for the removal of broken endodontic instruments. Materials and Methods: A total of 80 extracted human first mandibular molars with moderate root canal curvature were selected. Following access cavity preparation canal patency was established with a size 10/15 K-file in the mesiobuccal canals of all teeth. The teeth were divided into 2 groups of 40 teeth each: the P group (ProUltra tips) and the T group (TFRK). Each group was further subdivided into 2 smaller groups of 20 teeth each according to whether ProTaper F1 rotary instruments were fractured in either the coronal third (C constituting the PC and TC groups) or the middle third (M constituting the PM and TM groups). Instrument retrieval was performed using either ProUltra tips or the TFRK. Results: The overall success rate at removing the separated instrument was 90% in group P and 95% in group T (p > 0.05) The mean time for instrument removal was higher with the ultrasonic tips than with the TFRK (p > 0.05). Conclusion: Both systems are acceptable clinical tools for instrument retrieval but the loop device in the TFRK requires slightly more dexterity than is needed for the ProUltra tips.

• Restorative Dentistry and Endodontics
• /
• 제40권2호
• /
• pp.155-160
• /
• 2015

Objectives: Achieving adequate anesthesia with inferior alveolar nerve blocks (IANB) is of great importance during dental procedures. The aim of the present study was to assess the success rate of two anesthetic agents (bupivacaine and lidocaine) for IANB when treating teeth with irreversible pulpitis. Materials and Methods: Sixty volunteer male and female patients who required root canal treatment of a mandibular molar due to caries participated in the present study. The inclusion criteria included prolonged pain to thermal stimulus but no spontaneous pain. The patients were randomly allocated to receive either 2% lidocaine with 1:80,000 epinephrine or 0.5% bupivacaine with 1:200,000 epinephrine as an IANB injection. The sensitivity of the teeth to a cold test as well as the amount of pain during access cavity preparation and root canal instrumentation were recorded. Results were statistically analyzed with the Chi-Square and Fischer's exact tests. Results: At the final step, fifty-nine patients were included in the study. The success rate for bupivacaine and lidocaine groups were 20.0% and 24.1%, respectively. There was no significant difference between the two groups at any stage of the treatment procedure. Conclusions: There was no difference in success rates of anesthesia when bupivacaine and lidocaine were used for IANB injections to treat mandibular molar teeth with irreversible pulpitis. Neither agent was able to completely anesthetize the teeth effectively. Therefore, practitioners should be prepared to administer supplemental anesthesia to overcome pain during root canal treatment.

• Restorative Dentistry and Endodontics
• /
• 제42권3호
• /
• pp.200-205
• /
• 2017

Objectives: The aim of this in vivo study was to assess the accuracy of 2 third-generation electronic apex locators (EALs), Propex II (Dentsply Maillefer) and Root ZX II (J. Morita), and radiographic technique for locating the major foramen (MF). Materials and Methods: Thirty-two premolars with single canals that required extraction were included. Following anesthesia, access, and initial canal preparation with size 10 and 15 K-flex files and SX and S1 rotary ProTaper files, the canals were irrigated with 2.5% sodium hypochlorite. The length of the root canal was verified 3 times for each tooth using the 2 apex locators and once using the radiographic technique. Teeth were extracted and the actual WL was determined using size 15 K-files under a ${\times}25$ magnification. The Biostat 4.0 program (AnalystSoft Inc.) was used for comparing the direct measurements with those obtained using radiographic technique and the apex locators. Pearson's correlation analysis and analysis of variance (ANOVA) were used for statistical analyses. Results: The measurements obtained using the visual method exhibited the strongest correlation with Root ZX II (r = 0.94), followed by Propex II (r = 0.90) and Ingle's technique (r = 0.81; p < 0.001). Descriptive statistics using ANOVA (Tukey's post hoc test) revealed significant differences between the radiographic measurements and both EALs measurements (p < 0.05). Conclusions: Both EALs presented similar accuracy that was higher than that of the radiographic measurements obtained with Ingle's technique. Our results suggest that the use of these EALs for MF location is more accurate than the use of radiographic measurements.

• Restorative Dentistry and Endodontics
• /
• 제46권3호
• /
• pp.33.1-33.12
• /
• 2021

Objectives: This study aimed to investigate the efficacy of ionic and non-ionic-based contrast media (in vitro study) and the combinatorial effect of chitosan-based endo-radiopaque solution (CERS) (in vivo study) for visualization of the root canal anatomy. Materials and Methods: In vitro study (120 teeth): The root canal of maxillary premolars and molars (in vitro group 1 and 2 respectively, n = 60 each) were analyzed using 4 different contrast media (subgroups: Omnipaque 350, Iopamidol, Xenetix 350, and Urografin 76; n = 15 each) in combination with 5.25% sodium hypochlorite (NaOCl). Based on the results of the in vitro study, in vivo study (80 teeth) was done to compare Xenetix 350 + 5.25% NaOCl with CERS (in vivo group 1 and 2 respectively, n = 40 each) on maxillary and mandibular premolars and molars. Two endodontists used radiovisiography to assess the depth of ingress and identify the aberrant root anatomy after access cavity preparation, and after initial cleaning and shaping of canals. Kruskal-Wallis test was used for in vitro comparison (p < 0.05), and Wilcoxon signed-rank test and Mann-Whitney U test for in vivo analysis (p < 0.01). Results: In vitro study, Xenetix 350 + 5.25% NaOCl facilitated a significant higher visualization (p < 0.05). For in vivo study, CERS had a statistically significant depth of ingress (p < 0.01), and was efficient in identifying the aberrant root canal anatomy of premolars and molars. Conclusions: CERS facilitates better visualization of the root canal anatomy of human premolars and molars.

• Clinical Endoscopy
• /
• 제56권3호
• /
• pp.283-289
• /
• 2023

Gastrointestinal (GI) bleeding is one of the most common conditions among patients visiting emergency departments in Korea. GI bleeding is divided into upper and lower GI bleeding, according to the bleeding site. GI bleeding is also divided into overt and occult GI bleeding based on bleeding characteristics. In addition, obscure GI bleeding refers to recurrent or persistent GI bleeding from a source that cannot be identified after esophagogastroduodenoscopy or colonoscopy. The small intestine is the largest part of the alimentary tract. It extends from the pylorus to the cecum. The small intestine is difficult to access owing to its long length. Moreover, it is not fixed to the abdominal cavity. When hemorrhage occurs in the small intestine, the source cannot be found in many cases because of the characteristics of the small intestine. In practice, small-intestinal bleeding accounts for most of the obscure GI bleeding. Therefore, in this review, we introduce and describe systemic approaches and examination methods, including video capsule endoscopy and balloon enteroscopy, that can be performed in patients with suspected small bowel bleeding in clinical practice.

• 대한소아치과학회지
• /
• 제23권3호
• /
• pp.746-763
• /
• 1996

An alternative design to conventional class II cavity preparation for proximal carious lesions is the tunnel preparation. It preserves the marginal ridge intact, thus making it possible to maintain the natural contact relationship with the adjacent tooth and minimize tooth reduction. This in vitro study was purposed to evaluate the effect of the materials' elastic constants and shear-bond strength on the marginal ridge fracture resistance of teeth restored by the tunnel technique, and to find the materials of choice for tunnel restorations. $Resinomer^{(R)}$, $Ketac-silver^{(R)}$, $Miracle-Mix^{(R)}$, and Tytin were used as restorative material. The elastic constants of each restorative material were evaluated by ultrasonic pulse measurement. Young's modulus and bulk modulus of the restorative materials were evaluated in three specimens for each material type. The shear-bond strength of the restorative materials to the dentin surface was measured after thermocycling 400 times between 6 and $60^{\circ}C$, using ten specimens for each material type. For measuring marginal ridge strength, 60 sound extracted molar teeth were distributed into six groups by size. Sound molar teeth were used as a Control group and unfilled prepared teeth were grouped as Unrestored. Another four groups were named Resinomer group, Ketac-Silver group, Miracle Mix group, and Tytin group by type of restorative material. Tunnel cavity preparation was done with ' 1/2, 2, and 4 round burs in sequence. Initial access to proximal surface was made through an occlusal access preparation started at least 2mm from the marginal ridge, and the proximal opening was formed about 2.5mm below the marginal ridge. After restoration and thermocycling, marginal ridge strength was measured using a universal testing machine. The results were as follows: 1. The Young's modulus of $Tytin^{(R)}$ was 63.95 GPa, followed by $Ketac-Silver^{(R)}$ 27.60 GPa, $Miracle-mix^{(R)}$ 18.48 GPa, and $Resinomer^{(R)}$ 10.74 GPa showing significant differences between the groups(P<0.05). The bulk modulus of the materials showed the same order as Young's modulus. The value of $Tytin^{(R)}$ showed 59.57 GPa indicating that it will deform less than other materials under the same stress. It was followed by $Ketac-Silver^{(R)}$ 23.57 GPa, Miracle $Mix^{(R)}$ 12.50 GPa, and $Resinomer^{(R)}$ 11.60 GPa. 2. The Resinomer group had a shear-bond strength of 7.41 MPa which was significantly higher than those of the Ketac-Silver group (1.80 MPa) and the Miracle Mix group (2.84 MPa) (P<0.01). All the specimens of Tytin group detatched from the dentin surface during thermocycling. 3. The mean marginal ridge strength of the Unrestored group(46.14 kgf) was significantly lower than that of the Control group (84.24 kgf) (P<0.01). The marginal ridge strength of teeth restored by the tunnel technique was, in order, Ketac-Silver group 74.06 kgf, Miracle Mix group 73.36 kgf, Resinomer group 63.47 kgf, and Tytin group 58.76 kgf. The Ketac-Silver, Miracle Mix, and Resinomer groups showed no significant difference with the Control group (P>0.05), but the Tytin group showed significantly lower strength compared to the Control group(P<0.05). The results showed that the marginal ridge strength of the teeth restored by the tunnel technique was not significantly lower than that of sound teeth. They also demonstrated that the bonding strength of the restorative material to the tooth surface should be high and the modulus of elasticity should not be lower than that of the tooth in order to restore the marginal ridge strength to its natural condition.

• Journal of Chest Surgery
• /
• 제37권3호
• /
• pp.252-260
• /
• 2004

다량의 흉수는 수술 전 방사선 검사로 쉽게 평가할 수 있지만, 미량의 흉수나 흉막의 미세전이를 평가하는 것은 매우 어렵다. 본 연구는 원발성 폐암 환자에서 미량의 흉수나 흉막의 미세전이 여부가 예후에 미치는 영향을 연구하기 위해 흉강 세척액 세포검사를 시행해서 그 결과를 분석하였다. 1998년 11월부터 2002년 8월까지 서울아산병원 흉부외과에서 원발성 폐암으로 폐절제술을 시행받은 환자 중 수술 전 방사선 검사에서 흉수가 없고, 수술 소견에서 종양의 흉벽 침범 소견이 없고, 광범위한 흉막 유착 소견이 없었던 315명을 대상으로 삼아 전향적으로 연구하였다. 흉강 세척액은 개흉 직후와 수술이 끝나고 흉강을 봉합하기 직전에 생리식염수 100 mL로 흥강을 세척해서 검체를 얻어 세포조직학적 검사를 시행하였다. 대상 환자는 남자 237명, 여자 78명이며, 평균 연령은 60.8$\pm$9.7세(27∼82세)였다. 315명의 흉강 세척액 세포검사에서 악성세포가 발견된 경우는 총 28예(8.9%)였으며, 20예(6.3%)는 개흉 직후 시행한 흉강 세척액 세포검사에서 악성세포가 발견되었다. 흉강 세척액 세포검사에서 악성세포의 양성률은 조직학적 세포형, 림프절 전이, 장측 흉막 침범 여부 등과 통계학적으로 유의한 차이가 없었다. Stage I 및 II 환자 중 흉강 세척액 세포검사에서 악성세포가 음성인 군은 1년 생존율이 93.9%인 반면 양성인 군은 85.7%로 통계학적으로 유의한 차이가 없었다. 재발은 31예(13.6%)에서 있었고, 2-year recurrence-free rate는 흉강 세척액 세포검사에서 악성세포가 음성인 군(90.1%)과 양성인 군(87.5%) 사이에 유의한 차이를 보이지 않았다. 대상 환자들의 중간 추적기간은 16.4개월(1∼48개월)였다. 원발성 폐암으로 폐절제술을 받은 환자에서 시행한 흉강 세척액 세포검사에서 악성세포의 존재 유무는 수술 후 생존율이나 재발률에 있어 통계학적으로 유의한 영향을 미치지 않았지만 대상 환자들의 평균 추적기간이 짧은 점 등을 고려할 때 향후 지속적인 연구가 필요하다고 생각한다.

• 한국전자파학회논문지
• /
• 제17권10호
• /
• pp.967-975
• /
• 2006

본 논문에서는 40 GHz 대역에서 동작하는 IEEE 802.16 고정 무선 통신을 위한 천이, 소형 TDD 송수신 모듈의 front-end 모듈을 설계하고 구현하는 방법을 제안한다. 제안된 모듈은 저손실과 소형화를 동시에 달성하기 위하여 캐비티 공정을 가지는 다층 LTCC 기술을 이용하여 제작되었다. 스위치의 입출력단에 와이어본드 정합회로의 설계 및 안테나와의 연결을 위한 도파관 천이 구조를 통해 저손실의 천이를 얻었으며, 기존 금속 도파관 필터를 대체한 유전체 도파관 필터를 사용함으로써 소형화를 달성하였다. 이를 구현하기 위해 유전율 7.1, 두께 100 um인 총 6층의 LTCC 기판을 사용하였으며 제작된 소형 front-end 모듈의 크기는 $30{\times}7{\times}0.8mm^3$이다. 그리고 송수신 삽입 손실 < 5.3 dB, 이미지 신호 제거 > 49 dB의 우수한 천이를 얻을 수 있었다.

• Restorative Dentistry and Endodontics
• /
• 제21권1호
• /
• pp.1-18
• /
• 1996

There are many advantages when using IIF and DNA probe methods over anaerobic culture method in that they are time-and effort-saving, more precise and more sensitive. Furthermore, in IIF and DNA probe methods, the detection is possible only with small amount of bacteria, the quantitative analysis is possible, and the cell viability is not necessary. The purpose of this study is to observe the incidence of P.endodontalis by carrying out anaerobic culture, IIF and colony lift using DNA probe method respectively, and to compare these 3 methods in terms of effectiveness and sensitivity in order to identify the most effective detection method. 30 teeth with at least one clinical symptoms, with single canal, and with pulp necrosis were sampled. For sampling bacteria, access cavity was prepared after disinfecting tooth and its surroundings. Then the paper point was inserted up to the periapical area, leave there for a while, and finally it was placed into PRAS Ringer's sol. and PBS sol. In anaerobic culture method, P.endodontalis was identified by biochemical tests after subculturing black and brown colonies which were produced after 7 days of incubation on BAP and Brucella BAP in anaerobic chamber. To identify P.endodontalis in IIF method, species-specific polyclonal rabbit-antisera of P.endodontalis(ATCC 35406) was reacted with sampled PBS sol. dispensed onto glass slide, and then P.endodontalis was examined by phase contrast microscopy after incubating with Goat anti-rabbit lgG conjugated to Fluorescein isothiocyanate. For colony lift using DNA probe method, membranes were laid over colonies on the surface of BAP and were hybridized with cloned DNA probe of P.endodontalis. The existence of P.endodontalis was then identified by the methods of chemiluminescent detection and color metric detection. Black colony was found in 11 teeth out of 30 teeth and P.endodontalis was detected in 6 teeth (20 %) by anaerobic culture method, 16 teeth (53 %) by IIF method, and 7 teeth (23 %) by DNA probe method. IIF method is significantly better in detecting P.endodontalis than DNA probe method and anaerobic culture method. There was no significant differences between DNA probe method and anaerobic culture method. There was significant correlation between the formation of black colony and the existence of P.endodontalis. The probability of detecting P.endodontalis when black colony being present is 2.89 times higher than when not being present. There was significant relationship between the foul odor of clinical symptoms and P.endodontalis. The sensitivity of existing P.endodontalis when foul odor being present was 93.75 %, while the specificity of not existing P.endodontalis when foul odor not being present was 28.57 %. These results suggested that the probes of P.endodontalis will be used to decide the method and prognosis in endodontic treatments.

• 한국임상수의학회지
• /
• 제33권4호
• /
• pp.214-217
• /
• 2016

A 10-year-old, 24.1 kg, intact female Siberian husky dog (case 1) and 11-year-old, 5.0 kg, intact male Shihtzu dog (case 2) presented with chief complaints of polydipsia, anorexia, vomiting and exercise intolerance (case 1) and stranguria (case 2). Splenic nodule (case 1) and mass (case 2) were identified in these patients through ultrasonographic examination. Laparoscopic splenectomy was conducted for the histopathologic evaluation. In addition, laparoscopic ovariohysterectomy, liver biopsy (case 1) and castration (case 2) were performed for treatment or diagnosis of primary symptoms. Under general anesthesia, 5 mm three-portal access laparoscopic splenectomy was performed using the Sonicision$^{TM}$ equipment. The dogs were rotated onto right lateral recumbency. The spleen was elevated using a fan or goldfinger retractor, which revealed the ventral aspect of the spleen. Resection of vessels was started at the caudal aspect of the spleen using the Sonicision$^{TM}$. The excised spleen was removed from the abdominal cavity using a 12 mm endo-bag via the enlarged instrument portal. There were no post-operative complications in either patient. Histopathologic diagnoses were splenic lymphoid hyperplasia (case 1) and splenic nodular hyperplasia (case 2). Based on our experience, laparoscopic splenectomy is sufficient to replace traditional splenectomy in small animal surgery. The use of the Sonicision$^{TM}$ could be a novel surgical technique for three-portal laparoscopic splenectomy, regardless of patient size.