• Imaging Science in Dentistry
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• 제50권1호
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• pp.1-7
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• 2020

Purpose: This study was performed to evaluate the magnitude of artifacts produced by gutta-percha and metal posts on cone-beam computed tomography (CBCT) scans obtained with different tube currents and with or without metal artifact reduction (MAR). Materials and Methods: A tooth was inserted in a dry human mandible socket, and CBCT scans were acquired after root canal instrumentation, root canal filling, and metal post placement with various tube currents with and without MAR activation. The artifact magnitude was assessed by the standard deviation (SD) of gray values and the contrast-to-noise ratio (CNR) at the various distances from the tooth. Data were compared using multi-way analysis of variance. Results: At all distances, a current of 4 mA was associated with a higher SD and a lower CNR than 8 mA or 10 mA (P<0.05). For the metal posts without MAR, the artifact magnitude as assessed by SD was greatest at 1.5 cm or less (P<0.05). When MAR was applied, SD values for distances 1.5 cm or closer to the tooth were reduced (P<0.05). MAR usage did not influence the magnitude of artifacts in the control and gutta-percha groups(P>0.05). Conclusion: Increasing the tube current from 4 mA to 8 mA may reduce the magnitude of artifacts from metal posts. The magnitude of artifacts arising from metal posts was significantly higher at distances of 1.5 cm or less than at greater distances. MAR usage improved image quality near the metal post, but had no significant influence farther than 1.5 cm from the tooth.

• Biomolecules & Therapeutics
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• 제18권4호
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• pp.469-476
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• 2010

This study was to investigate the effect of apigenin on the bioavailability of paclitaxel after oral and intravenous administration in rats. The effect of apigenin on P-glycoprotein (P-gp), cytochrome P450 (CYP)3A4 activity was evaluated. The pharmacokinetic parameters of paclitaxel were determined in rats after oral (40 mg/kg) or intravenous (5 mg/kg) administration of paclitaxel with apigenin (0.4, 2 and 8 mg/kg) to rats. Apigenin inhibited CYP3A4 activity with 50% inhibition concentration ($IC_{50}$) of 1.8 ${\mu}M$. In addition, apigenin significantly inhibited P-gp activity. Compared to the control group, apigenin significantly increased the area under the plasma concentration-time curve (AUC, p<0.05 by 2 mg/kg, 59.0% higher; p<0.01 by 8 mg/kg, 87% higher) of oral paclitaxel. Apigenin also significantly (p<0.05 by 2 mg/kg, 37.2% higher; p<0.01 by 8 mg/kg, 59.3% higher) increased the peak plasma concentration ($C_{max}$) of oral paclitaxel. Apigenin significantly increased the terminal half-life ($t_{1/2}$, p<0.05 by 8 mg/kg, 34.5%) of oral paclitaxel. Consequently, the absolute bioavailability (A.B.) of paclitaxel was significantly (p<0.05 by 2 mg/kg, p<0.01 by 8 mg/kg) increased by apigenin compared to that in the control group, and the relative bioavailability (R.B.) of oral paclitaxel was increased by 1.14- to 1.87-fold. The pharmacokinetics of intravenous paclitaxel were not affected by the concurrent use of apigenin in contrast to the oral administration of paclitaxel. Accordingly, the enhanced oral bioavailability by apigenin may be mainly due to increased intestinal absorption caused via P-gp inhibition by apigenin rather than to reduced renal and hepatic elimination of paclitaxel. The increase in the oral bioavailability might be mainly attributed to enhanced absorption in the gastrointestinal tract via the inhibition of P-gp and reduced first-pass metabolism of paclitaxel via the inhibition of the CYP3A subfamily in the small intestine and/or in the liver by apigenin. It appears that the development of oral paclitaxel preparations as a combination therapy is possible, which will be more convenient than the i.v. dosage form.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권6호
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• pp.497-503
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• 2004

One of the most difficult problems to damage in dentistry is an odontogenic infection. These infections may range from low-grade, well-localized infections that require only minimal treatment to a severe, life-threatenig fascial space infection. Although the overwhelming majority of odontogenic infections are easily managed by minor surgical procedures and supportive medical therapy that includes antibiotic administration, the practitioner must constantly bear in mind that these infections may become severe in a very short time. We made an investigation was targeting on 78 male and 47 female patients (125 patients in total) who had been hospitalized because of the fascial space abscess on the oral and maxillofacial area and gained a complete recovery in Daegu Catholic University Hospital, Oral & Maxillofacial Surgery from January 1999 to December 2003. By tracing their charts, we could grasp the characteristics such as age, gender, the time of breakout and specific areas of the attacks, making a conclusive study of the statistical analysis and finally, we could reach conclusions. Now, we report the conclusion from the investigation with the literature. The proportion of males and females was approximately 3 to 2, and in age group, patients under 10 years old marked the highest, 22.4%. The patients between the age of 10 and 40 were only 14.4%, yet those who were between 40 and 80 marked 53.6% in contrast. In the monthly distribution, the order was Dec.(13.6%)-Sep.(12%)-Jan.(10.4%) and in seasonal distribution, it was winter(30.4%)-fall(28%)- summer(24.4%)- spring(19.2%). Considering the medical history, D.M. was the highest which was 30.3%, hypertension marked 24.4%, and the patients with both D.M. and hypertension were 9.0%. The major cause of infection of oral and maxillofacial areas was odontogenic infection, which marked about 96%, and especially the cases related to dental caries occurred most frequently, which was 51.2%. In the number of relaxed fascial space, single fascial space was 81.6%, and in the degree of relaxation of fascial space, the buccal space abscess marked 40.8%, following submandibular space abscess, which was 30.4%.

• Journal of Oral Medicine and Pain
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• 제32권1호
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• pp.45-55
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• 2007

천연 식물 추출물을 구강 질환 분야에 활용하는 방안이 다양하게 모색되고 있다. 본 연구는 편백나무에서 추출한 휘발성 정유인 피톤치드를 치의학분야에 활용하고자 치아우식증 원인균인 Streptococcus mutans GS5와 Streptococcus sobrinus 6715, 급진성 치주염에 관련된 Actinobacillus actinomycetemcomitans Y4에 대한 항균효과를 미생물학적으로 실험하였다. 흡광도 측정, 생균수 검사, 항생제 감수성 검사를 통해 다음과 같은 결과를 얻을 수 있었다. 1. 피톤치드의 최소억제농도(minimum inhibitory concentration; MIC)는 S. mutans GS5는 0.5%, S. sobrinus 6715는 1%, A. actinomycetemcomitans Y4는 0.2%로 측정되었다. 2. 피톤치드의 최소살균농도(minimum bactericidal concentration; MBC)는 S. mutans GS5는 0.5%, S. sobrinus 6715는 2%, A. actinomycetemcomitans Y4는 0.2%로 측정되었다. 3. 피톤치드에 노출된 실험균주에 대한 항생제 감수성 실험에서 피톤치드를 적용했을 경우, S. mutans GS5과 S. sobrinus 6715는 ampicillin에 대한 감수성이 유의성 있게 증가하였다. S. sobrinus 6715의 경우는 penicillin과 amoxicillin에 대한 감수성도 피톤치드에 의해 유의성 있게 증가하였다. 반면, A. actinomycetemcomitans Y4는 amoxicillin과 cefotaxime에 대한 감수성이 다소 증가하였으나 유의성은 없었다. 이상의 결과로, 편백 피톤치드 정유는 치아우식증 원인균인 Streptococcus mutans와 Streptococcus sobrinus, 급진성 치주염 원인균인 Actinobacillus actinomycetemcomitans에 대한 살균효과가 있을 뿐만 아니라 이들 균의 항생제 감수성을 높이는 것으로 판단된다. 따라서, 피톤치드는 치아우식증과 치주질환을 포함한 구강질환에 대해 예방적이고 치료적인 효과를 얻을 가능성이 있는 것으로 생각된다.

• Journal of Oral Medicine and Pain
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• 제26권2호
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• pp.161-171
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• 2001

In order to determine how oral mucosal change relates to inducing factors of burning mouth syndrome, the difference in pain perception scale and keratinization rate between burning mouth syndrome patients and normal subjects were investigated. Twenty patients (13 female, 7 male, mean age: 59 years), presenting in the Department of Oral Medicine, Chonnam National University Hospital were participated in this study. All subjects had been complaining of constant oral burning pain for more than a year, none took any strong analgesics, and none had oral mucosal lesions. Twenty volunteers (11 females, 9 males, mean age: 25 years) were also participated in this study as a control group. The control subjects had never had any symptoms of oral burning pain. A thermal stimulation using a Nd-YAG laser and cytological smear were carried out to anterodorsal part of tongue, tip of tongue, the left buccal mucosa, the lower lip mucosa and the chief complaint site. Stimulation of the dorsum of left hand was also carried out to contrast the mucosal area of burning mouth syndrome subjects and the control subjects. The laser output power could be adjusted from 0.75W to 4W. The pain perception scale of the burning mouth syndrome subjects were lower than in control subjects in the chief complaint area, the anterodorsal part of tongue and the buccal mucosa(p<0.01). The keratinization rate of burning mouth syndrome subjects, however, was higher keratinization rate than in normal subjects in the same area and lower lip mucosa(p<0.001). From above results, the anterodorsal part of tongue is the most appropriate site to use diagnostic laser stimulation. The higher level of keratinization and the lower level of thermal pain perception of the burning mouth syndrome subjects are explained as a protective mechanism against xerostomia and burning sensations. The application of Nd-YAG laser stimuli and cytological smear to oral mucosal surface could therefore be usefully employed as appropriate and standardized diagnostic tools for chronic orofacial pain subjects.

• Journal of Nutrition and Health
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• 제31권8호
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• pp.1315-1323
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• 1998

Effect of oral taurine supplementation on plasma total and phospholidpid -fatty acid profiles and their metabolism were evaluated in healthy female adults. Among twenty five female volunteers(23.6$\pm$0.3 years old ) participated in the taruine supplementation program(6g taurine /day), twenty four subjects succesfully completed the 2 week program , and only nine subjects continued to take taurine for another 2 weeks. Levels of plasma fatty acids and taruine were measured by gas-liquid chromatobraphy and an automated amino acid analyzer based on ion exchange chromatography, respectively. Plasma taurine concentration s of the subjects were 108. 7$\pm$3.4 , 184.2$\pm$8.2 and 235.9$\pm$77.0$\mu$emol/L at 0 , 2 and 4 weeks of taurine supplementation. Fatty acid compositions and elongation and desaturation indices of polyunsaturated fatty acids (PUFA) in plasma total lipids were not influenced by oral taurine supplementation. However, fatty acid compositions and their metabolism in plasma phospholipids were significantly affected by taurine supplementation in female adults. Compared to the values for 0 week, the percentage of saturated fatty acids (SFA) in plasma phospholipid was significantly lowered at 2 weeks, but elevated at 4 weeks of taurine supplementation. In contrast , the percentage of phospholipid PUFA significantly increased at 2 weeks and decreased at 4 weeks of taurine supplementation from to the values for 0 weeks. Foru weeks of oral taurine supplementation signifinatly elevated the eongation index(20 : 4$\omega$6 ⇒22 : 4 $\omega$6, p<0.01), and decreased the desaturation index (20 : 3 $\omega$6 ⇒20 : 4 $\omega$6 , p<0.01) of $\omega$6 fatty acids in plasma phospholipids. Plasma taurine concentration was positively correlated with the percentage of 14 : 0 fatty acids and the enlongation index o f$\omega$3 fatty acids(20 : 5 $\omega$3 ⇒22 : 5 $\omega$3), and thenegatively correlated with the percentage of 20 : 0 in plasma phospholipids. These results indicate that oral taurine supplementation for 4 weeks signidicantly elelvated the percentage of SFA, and lowered the percentage of PUFA in plasma phospholipids with no influence on plasm total fatty aicd composition in healthy female adults.

• Imaging Science in Dentistry
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• 제43권3호
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• pp.163-169
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• 2013

Purpose: Tonsilloliths are calcifications found in the crypts of the palatal tonsils and can be detected on routine panoramic examinations. This study was performed to highlight the benefits of cone-beam computed tomography (CBCT) in the diagnosis of tonsilloliths appearing bilaterally on panoramic radiographs. Materials and Methods: The sample group consisted of 7 patients who had bilateral radiopaque lesions at the area of the ascending ramus on panoramic radiographs. CBCT images for every patient were obtained from both sides of the jaw to determine the exact locations of the lesions and to rule out other calcifications. The calcifications were evaluated on the CBCT images using Ez3D2009 software. Additionally, the obtained images in DICOM format were transferred to ITK SNAP 2.4.0 pc software for semiautomatic segmentation. Segmentation was performed using contrast differences between the soft tissues and calcifications on grayscale images, and the volume in mm3 of the segmented three dimensional models were obtained. Results: CBCT scans revealed that what appeared on panoramic radiographs as bilateral images were in fact unilateral lesions in 2 cases. The total volume of the calcifications ranged from 7.92 to $302.5mm^3$. The patients with bilaterally multiple and large calcifications were found to be symptomatic. Conclusion: The cases provided the evidence that tonsilloliths should be considered in the differential diagnosis of radiopaque masses involving the mandibular ramus, and they highlight the need for a CBCT scan to differentiate pseudo- or ghost images from true bilateral pathologies.

• Biomolecules & Therapeutics
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• 제19권3호
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• pp.364-370
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• 2011

The purpose of this study was to investigate the effects of curcumin on the pharmacokinetics of loratadine in rats. The effect of curcumin on P-glycoprotein (P-gp) and cytochrome P450 (CYP) 3A4 activity was evaluated. Pharmacokinetic parameters of loratadine were also determined after oral and intravenous administration in the presence or absence of curcumin. Curcumin inhibited CYP3A4 activity with an IC50 value of 2.71 ${\mu}M$ and the relative cellular uptake of rhodamine-123 was comparable. Compared to the oral control group, curcumin significantly increased the area under the plasma concentration-time curve and the peak plasma concentration by 39.4-66.7% and 34.2-61.5%. Curcumin also significantly increased the absolute bioavailability of loratadine by 40.0-66.1% compared to the oral control group. Consequently, the relative bioavailability of loratadine was increased by 1.39- to 1.67-fold. In contrast, curcumin had no effect on any pharmacokinetic parameters of loratadine given intravenously, implying that the enhanced oral bioavailability may be mainly due to increased intestinal absorption caused via P-gp and CYP3A4 inhibition by curcumin rather than to reduced renal and hepatic elimination of loratadine. Curcumin enhanced the oral bioavailability of loratadine in this study. The enhanced bioavailability of loratadine might be mainly attributed to enhanced absorption in the gastrointestinal tract via the inhibition of P-gp and reduced fi rst-pass metabolism of loratadine via the inhibition of the CYP3A subfamily in the small intestine and/or in the liver by curcumin.

• Asian Pacific Journal of Cancer Prevention
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• 제17권2호
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• pp.619-623
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• 2016

Ameloblastoma is the most common epithelial odontogenic tumor. It may show locally invasive behavior resulting in recurrence and malignancy. Therefore, appropriate diagnosis of this tumor is necessary. The aim of this study was to evaluate clinicopathological characteristics of ameloblastomas in an Iranian population. We present a 40-year retrospective study of patients diagnosed from 1971 to 2010 in the Department of Oral and Maxillofacial Pathology, Faculty of Dentistry, Mashhad, Iran. Information gathered from patient records included age, gender, tumor location and histologic type. The frequency of odontogenic tumors among all lesions was 2.08% and ameloblastoma with 88 samples demonstrated the greatest prevalence (41.5%). Regarding gender, 60% of samples occurred in males. The mean age of studied patients was $33.02{\pm} 15.74years$ with a peak of occurrence in the third decade of life. The most frequent location of tumor was the mandibles (93.2%). Eighty five (96.6%) tumors were recorded as benign and 3 (3.4%) as malignant. Of benign tumors, 62 (72.9%), 20 (23.5%) and 3 (3.6%) cases were of conventional, unicyctic and peripheral types, respectively. In contrast to most previous studies, the most common histologic subtype in the present study was plexiform. Knowledge of the incidence of ameloblastoma and its clinicopathologic features including most common location, gender and age distribution in different ethnogeographic backgrounds is necessary for accurate diagnosis and proper treatment.

• Journal of Pharmaceutical Investigation
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• 제41권5호
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• pp.273-278
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• 2011

The aim of this study was to investigate the effect of efonidipine on the pharmacokinetics of warfarin after oral and intravenous administration of warfarin in rats. Warfarin was administered orally (0.2 mg/kg) or intravenously (0.05 mg/kg) without or with oral administration of efonidipine (1 or 3 mg/kg) in rats. The effect of efonidipine on the cytochrome P450 (CYP) 3A4 activity was also evaluated. Efonidipine inhibited CYP3A4 enzyme activity with 50% inhibition concentration ($IC_{50}$) of $0.08{\mu}M$. Compared to those in the oral control group (warfarin without efonidipine), the area under the plasma concentration-time curve (AUC) of warfarin was significantly greater (1 mg/kg, P<0.05; 3 mg/kg, P<0.01) by 25.9-59.0%, and the peak plasma concentration ($C_{max}$) was significantly higher (3 mg/kg, P<0.05) by 26.2% after oral administration of warfarin with efonidipine, respectively. The total body clearance of warfarin was significantly (3 mg/kg, P<0.05) decreased by efonidifine. Consequently, the relative bioavailability of warfarin was increased by 1.26- to 1.59-fold and the absolute bioavailability of warfarin with efonidipine was significantly greater by 59.7-75.4 % compared to that in the control group (47.4%). In contrast, efonidipine had no effect on any pharmacokinetic parameters of warfarin given intravenously. Therefore, the enhanced oral bioavailability of warfarin may be due to inhibition of CYP 3A4-mediated metabolism in the intestine and/or liver and to reduction of total body celarance rather than renal elimination, resulting in reducing first-pass metabolism by efonidipine.