Secreotory Leukocyte Protease Inhibitor Regulates Bone Formation via RANKL, OPG, and Runx2 in Rat Periodontitis and MC3T3-E1 Preosteoblast / 치위생과학회지

Background@#Secretory leukocyte protease inhibitor (SLPI) protects tissues from proteases and promotes cell proliferation andhealing. SLPI also reduces periodontal inflammation and alveolar bone resorption by inhibiting proinflammatory cytokine expression in rat periodontal tissues and osteoblasts. However, little is known of the role of SLPI in the expression of osteoclast regulatory factors from osteoblasts, which are crucial for the interaction between osteoblasts and osteoclasts. Therefore, we aimed to determine the effects of SLPI on the regulation of osteoclasts and osteoblasts in LPS-treated alveolar bone and osteoblasts. @*Methods@#Periodontitis was induced in rats using LPS. After each LPS injection, SLPI was injected into the same area. Immu-nohistochemical analysis was performed with antibodies against SLPI, RANKL, OPG, and Runx2 in the periodontal tissue. RT-PCR and western blotting were performed to determine the expression levels of SLPI, RANKL, OPG, and Runx2 in LPS- and SLPI/LPS-treated MC3T3-E1 cells. SLPI/LPS-treated MC3T3-E1 cells were also stained with Alizarin Red S. @*Results@#Immunohistochemical analysis showed that the expression levels of SLPI, OPG, and Runx2 were higher while that of RANKLwas lower in the LPS/SLPI group relative to those in the LPS group. The mRNA and protein expression of SLPI, OPG, and Runx2 was higher in SLPI/LPS/MC3T3-E1 cells than in LPS/MC3T3-E1 cells, and RANKL expression was lower. During differentiation, OPG and Runx2 protein levels were higher whereas RANKL levels were lower in SLPI/LPS/MC3T3-E1 than in LPS/MC3T3-E1 cells on days 0, 4, 7, and 10. In addition, mineralization and matrix deposition were higher in SLPI/LPS/MC3T3-E1 than in LPS/MC3T3-E1 on days 7 and 10. SLPI decreased RANKL expression in LPS-treated alveolar bone and osteoblasts but increased the expression of OPG and Runx2. @*Conclusion@#SLPI can be considered as a regulatory molecule that indirectly regulates osteoclast activation via osteoblasts andpromotes osteoblast differentiation.

A study on the pathway for severe emergency patients visiting emergency departments to establish regionalization of emergency medical services in Busan, Ulsan, and Gyeongsangnam-do regions

Objective@#This study assessed the characteristics of medical utilization by analyzing the pathway of severe emergency patients visiting emergency departments in the three regions. @*Methods@#The study was conducted based on the National Emergency Department Information System, which collected information from 43 local governments from 2017 to 2019. Severe emergency patients were classified according to the Korean Triage and Acuity Scale level. A map was produced based on the results of connectivity centrality analysis, and groupings were performed using the R program. The relevance index was calculated to confirm medical utilization within and among regions. @*Results@#Medical utilization within the region for severe emergency patients was concentrated in major cities. With the opening of local emergency medical agencies in underserved areas of emergency medical services, medical utilization within the region has increased compared to three years ago. Severe emergency patients in the western region of Gyeongsangnam-do mainly visit the emergency department in Jinju city. In contrast, in western county areas, they mainly visit the emergency department in Busan city. In Ulsan city, which belongs to Ulju county and Jung-gu, many patients frequently visit the emergency department in Yangsan city. Patients from Geochang, Changnyeong, Hamyang, and Hapcheon counties in Gyeongnam Province frequently visit the emergency department in Daegu city. @*Conclusion@#The intersection and cooperation of health resources within and between regions of the emergency medical system are no longer a task that can be postponed, and regionalization has been proposed as an alternative concept.

Comparative Morphological Study on Parotid and Submandibular Salivary Glands in Ovariectomized Rats / 치위생과학회지

Background@#Estrogen deficiency affects the structure and function of the salivary glands in women, leading to a decrease in salivary secretion and a change in the composition of saliva. Previous studies on changes in the salivary glands that cause estrogen deficiency have reported only partial results for the parotid and submandibular glands, and there are few comparative morphological studies of histological changes between the parotid and submandibular glands in ovariectomized rats (OVX) leading to estrogen deficiency. This study aimed to analyze the histopathological and histochemical changes in the parotid and submandibular salivary glands causing estrogen deficiency by using OVX, and to discuss the mechanism on these changes. @*Methods@#The parotid and submandibular glands from sacrificed control and OVX groups were fixed with cold 4% paraformaldehyde in phosphate buffer (pH 7.2). The tissues were dehydrated using a series of graded ethyl alcohol and embedded in paraffin. For histopathological analysis, sections cut to a thickness of 6 to 7 μm were stained with hematoxylin and eosin (H&E). For histochemical analysis, Periodic acid-Schiff (PAS), Alcian blue (AB, pH 2.5), and PAS+AB (pH 2.5 and pH 1) staining was performed. @*Results@#Histopathological analysis of OVX tissue showed that the parotid and submandibular salivary glands were broadly and clearly separated and divided into lobes. In OVX, acinar and ductal cells with condensed polymorphic or pyknotic nucleus, which are presumed to be characteristic of apoptotic cells, and degenerated cells with lipid deposition in cytoplasmic granules and ruptured membranes were increased. Histochemical analysis of OVX, confirmed an increase in the number and acidification of acinar secretory granules. @*Conclusion@#Histopathological and histochemical changes and the effects of estrogen deficiency are more evident in the submandibular salivary gland than in the parotid gland.

Effects of Calamansi Soju and Other Alcoholic Beverages on Resin Restorations / 치위생과학회지

Background@#The purpose of this study was to investigate the effects of commercially available calamansi soju and other alcoholic beverages on the microhardness and erosion of resin restorations. @*Methods@#In this study, we evaluated the effects of Calamansi soju, Chamisul fresh, Cass fresh, and Gancia Moscato D’asti on resin restorations. Jeju Samdasoo and Coca-Cola were used as negative and positive controls, respectively. Specimens to be immersed in the beverages were manufactured using composite resin according to the product instructions. In each group, the surface microhardness was measured using a surface microhardness instrument before and after immersion for 5, 15, 30, and 60 minutes. The pattern of change in the surface of the composite resin was observed under a scanning electron microscope (SEM). Paired t-tests, one-way ANOVA, and repeated measures ANOVA were performed to compare the surface microhardness of the specimens, and the Tukey test was used as a post hoc test. @*Results@#The pH of all beverages except Jeju Samdasoo was ＜5.5, which is the critical pH that can induce erosion. The difference in surface microhardness of the composite resin before and after immersion for 60 minutes was significant in all groups. In particular, the largest change in surface microhardness was observed in the calamansi soju group. In the SEM analysis, loss of composite resin was observed in all groups except the Jeju Samdasoo group, and rough surfaces with pores of various sizes were observed. @*Conclusion@#In this study, all beverages except Jeju Samdasoo decreased the microhardness of the composite resin surface, and it was confirmed that calamansi soju had the greatest change.

Inhibitory Effects on Oral Microbial Activity and Production of Lipopolysaccharides-Induced Pro-Inflammatory Mediators in Raw264.7 Macrophages of Ethanol Extract of Perilla flutescens (L.) Britton / 치위생과학회지

Background@#The leaves of Perilla frutescens, commonly called perilla and used for food in Korea, contain components with a variety of biological effects and potential therapeutic applications. The purpose of this study was to identify the components of 70% ethanol extracted Perilla frutescens (EEPF) and determine its inhibitory effects on oral microbial activity and production of nitric oxide (NO) and prostaglandin E2 (PGE2) in lipopolysaccharides (LPS)-stimulated Raw264.7 macrophages, consequently, to confirm the possibility of using EEPF as a functional component for improving the oral environment and preventing inflammation. @*Methods@#One kg of P. frutescens leaves was extracted with 70% ethanol and dried at −70o C. EEPF was analyzed using high-performance liquid chromatography analysis, and antimicrobial activity against oral microorganisms was revealed using the disk diffusion test. Cell viability was elucidated using a methylthiazolydiphenyl-tetrazolium bromide assay, and the effect of EEPF on LPS-induced morphological variation was confirmed through microscopic observation. The effect of EEPF on LPS-induced production of pro-inflammatory mediators, NO and PGE2 was confirmed by the NO assay and PGE2 enzyme-linked immunosorbent assay. @*Results@#The main component of EEPF was rosemarinic acid, and EEPF showed weak anti-bacterial and anti-fungal effects against microorganisms living in the oral cavity. EEPF did not show toxicity to Raw264.7 macrophages and had inhibitory effects on the morphological variations and production of pro-inflammatory mediators, NO and PGE2 in LPS-stimulated Raw264.7 macrophages. @*Conclusion@#EEPF can be used as a functional material for improving the oral environment through the control of oral microorganisms and for modulating inflammation by inhibiting the production of inflammatory mediators.

Effect of Commercial Effervescent Vitamin Tablets on Bovine Enamel / 치위생과학회지

BACKGROUND: In this study, four types of effervescent vitamins marketed in Korea were analyzed for their acidity and vitamin content. For this purpose, bovine teeth were immersed in vitamin, and surface microhardness and appearance were measured before and after immersion to evaluate tooth demineralization and erosion.METHODS: Bovine permanent incisors with sound surface enamel were cut to 5×5 mm size, embedded in acrylic resin, and polished using a polishing machine with Sic-paper. The prepared samples were analyzed for pH, vitamin content, and surface hardness before and after immersion using a surface microhardness meter. Demineralization of surface dental enamel was observed using a scanning electron microscope.RESULTS: The average pH of the four effervescent vitamins was less than 5.5; the pH of the positive control Oronamin C was the lowest at 2.76, while that of the negative control Samdasoo was the highest at 6.86. The vitamin content was highest in Berocca and lowest in the DM company Multivitamin. On surface microhardness analysis, surface hardness values of all enamel samples were found to be decreased significantly after 1 and 10 minutes of immersion (p<0.05). After 10 minutes of immersion, there was a significant difference in the decrease in hardness between the experimental groups (p<0.05). Scanning electron microscopy observation showed that dental enamel demineralization after 10 minutes of immersion was the most severe in Oronamin C except for Samdasoo, followed by DM company Multivitamin and VitaHEIM. Immersion in BeroNew and Berocca resulted in similar effects.CONCLUSION: There is a risk of tooth erosion due to decreased tooth surface microhardness when using the four types of effervescent vitamins and vitamin carbonated beverages with pH below 5.5. Therefore, high pH vitamin supplements are recommended to prevent tooth erosion.

Inflammatory Effect of Light-Emitting Diodes Curing Light Irradiation on Raw264.7 Macrophage / 치위생과학회지

BACKGROUND: The light-emitting diode (LED) curing light used is presumed to be safe. However, the scientific basis for this is unclear, and the safety of LED curing light is still controversial. The purpose of this study was to investigate the effect of LED curing light irradiation according to the conditions applied for the polymerization of composite resins in dental clinic on the cell viability and inflammatory response in Raw264.7 macrophages and to confirm the stability of LED curing light. METHODS: Cell viability and cell morphology of Raw264.7 macrophages treated with 100 ng/ml of lipopolysaccharide (LPS) or/and LED curing light with a wavelength of 440~490 nm for 20 seconds were confirmed by methylthiazolydiphenyl-tetrazolium bromide assay and microscopic observation. The production of nitric oxide (NO) and prostaglandin E2 (PGE2) was confirmed by NO assay and PGE2 enzyme-linked immunosorbent assay kit. Expression of interleukin (IL)-1β and tumor necrosis factor (TNF)-α in total RNA and protein was confirmed by reverse transcription polymerase chain reaction and Western blot analysis. RESULTS: The LED curing light did not affect the viability and morphology of normal Raw264.7 cells but affected the cell viability and induced cytotoxicity in the inflammation-induced Raw264.7 cells by LPS. The irradiation of the LED curing light did not progress to the inflammatory state in the inflammation-induced Raw264.7 macrophage. However, LED curing light irradiation in normal Raw264.7 cells induced an increase in NO and PGE2 production and mRNA and protein expression of IL-1β and TNF-α, indicating that it is possible to induce the inflammatory state. CONCLUSION: The irradiation of LED curing light in RAW264.7 macrophage may induce an excessive inflammatory reaction and damage oral tissues. Therefore, it is necessary to limit the long-term irradiation which is inappropriate when applying LED curing light in a dental clinic.

Effect of Ultra-Soft and Soft Toothbrushes on the Removal of Plaque and Tooth Abrasion / 치위생과학회지

To improve the oral health status of Korean people, it is necessary to encourage proper oral hygiene management habits, such as toothbrushing, through appropriate health promotion techniques. Therefore, the purpose of this study was to evaluate the removal of plaque and tooth abrasion using ultra-soft (filament 0.11~0.12 mm) and soft toothbrushes for toothbrushing. The plaque removal was performed using a dentiform and Arti-spray, and the Patient Hygiene Performance (PHP) index was calculated as the sum total score divided by the total number of surfaces. In the abrasivity experiment, according to the number of brushings, a micro Vickers hardness tester was used, and a sample in the range of 280~380 Vickers hardness number was selected. The number of toothbrushing stroke were 1,800 (2 months), 5,400 (6 months), 10,800 (12 months), and 21,600 (24 months). The tooth abrasion was measured using a scanning electron microscope. Statistical analysis was performed using IBM SPSS Statistics 22.0 and a p-value < 0.05 was considered significant. According to the results, there was no statistically significant difference in the degree of plaque removal between ultra-soft and soft toothbrushes. The difference in tooth abrasion between before and after toothbrushing was found to be greater with the soft toothbrushes than with the ultra-soft toothbrushes. Therefore, the ultra-soft toothbrush not only lowers tooth damage by reducing tooth abrasion, but also shows a similar ability to remove plaque as soft toothbrushes.

Morphometric Analysis of the Facial Artery in Perioral Region / 체질인류학회지

The facial artery is the largest and main arterial supply of the face, and the inferior and superior labial arteries supply blood to the lower and upper lips and intersect on the opposite site. The aim of this study was to provide quantitative data on the course of facial artery and the distribution of inferior and superior labial artery in perioral region. The location, distance, course, and diameter of the facial artery, inferior labial artery, and superior labial artery were measured directly on 50 hemifacial cadavers of Koreans and statistically analyzed using oneway ANOVA. The facial artery was located 18.50 mm lateral to the mouth corners (Cheilions). The inferior labial artery at its origin was located 15.11 mm inferior and 19.63 mm lateral to the Cheilions. The superior labial artery at its origin was located 5.83 mm superior and 11.28 mm lateral to the Cheilions. The diameter of facial artery, inferior labial artery, and superior labial artery was 2.19, 1.56, and 1.48 mm, respectively. The courses of the facial artery and it's branches showed no significant differences on laterality except for the diameter of the superior labial artery (p=0.026). The buccal branch of facial artery was showed in 44% of the cases in the deep layer of perioral region. In conclusion, this study provides that the data will be useful in predicting the courses of the facial artery and helpful for reconstructive surgery in perioral region.

Histological assessment of the palatal mucosa and greater palatine artery with reference to subepithelial connective tissue grafting / 대한해부학회지

This study aimed to measure the thickness of the epithelium and lamina propria of the palatal mucosa and to elucidate the location of the greater palatine artery to provide the anatomical basis for subepithelial connective tissue grafting. Thirty-two maxillary specimens, taken from the canine distal area to the first molar distal area, were embedded in paraffin and stained with hematoxylin-eosin. The thickness of the epithelium and lamina propria of the palatal mucosa was measured at three positions on these specimens, starting from 3 mm below the alveolar crest and in 3-mm intervals. The location of the greater palatine artery was evaluated by using image-processing software. The mean epithelial thickness decreased significantly in the posterior teeth; it was 0.41, 0.36, 0.32, and 0.30 mm in the canine, first premolar, second premolar, and first molar distal areas, respectively. The lamina propria was significantly thicker in the canine distal; it was 1.36, 1.08, 1.09, and 1.05 mm, respectively. The mean length from the alveolar crest to the greater palatine artery increased toward the posterior molar; it was 7.76, 9.21, 10.93, and 11.28 mm, respectively. The mean depth from the surface of the palatal mucosa to the greater palatine artery decreased from the canine distal to the first premolar distal but increased again toward the posterior molar; it was 3.97, 3.09, 3.58, and 5.50 mm, respectively. Detailed histological assessments of the lamina propria of the palatal mucosa and the greater palatine artery are expected to provide useful anatomical guidelines for subepithelial connective tissue grafting.

MicroRNA Analysis during Cultured Odontoblast Differentiation

MicroRNAs (miRNAs, miRs) are about 21-25 nucleotides in length and regulate mRNA translation by base pairing to partially complementary sites, predominantly in the 3'-untranslated region (3'-UTR) of the target mRNA. In this study, the expression profile of miRNAs was compared and analyzed for the establishment of miRNA-related odontoblast differentiation using MDPC-23 cells derived from mouse dental papilla cells. To determine the expression profile of miRNAs during the differentiation of MDPC-23 cells, we employed miRNA microarray analysis, quantitative real-time PCR (qRT-PCR) and Alizaline red-S staining. In the miRNA microarray analysis, 11 miRNAs were found to be up- or down-regulated more than 3-fold between day 0 (control) and day 5 of MDPC-23 cell differentiation among the 1,769 miRNAs examined. In qRT-PCR analysis, the expression levels of two of these molecules, miR-194 and miR-126, were increased and decreased in the control MDPC-23 cells compared with the MDPC-23 cells at day 5 of differentiation, respectively. Importantly, the overexpression of miR-194 significantly accelerated mineralization compared with the control cultures during the differentiation of MDPC-23 cells. These results suggest that the miR-194 augments MDPC-23 cell differentiation, and potently accelerates the mineralization process. Moreover, these in vitro results show that different miRNAs are deregulated during the differentiation of MDPC-23 cells, suggesting the involvement of these genes in the differentiation and mineralization of odontoblasts.

Cortical and cancellous bone thickness on the anterior region of alveolar bone in Korean: a study of dentate human cadavers

PURPOSE: The cortical bone thickness on the anterior region is important for achieving implant stability. The purpose of this study was to examine the thickness of the cortical and cancellous bones on the anterior region of the maxilla and mandible. MATERIALS AND METHODS: Twenty-five cadaver heads were used (16 male and 9 female; mean death age, 56.7 years). After the long axis of alveolar process was set up, it was measured in 5 levels starting from 2 mm below the cementoenamel junction (L1) at intervals of 3 mm. All data was analysed statistically by one-way ANOVA at the .05 significance level. RESULTS: The cortical bone thickness according to measurement levels in both the labial and lingual sides increased from L1 to L5, and the lingual side below L3 was significantly thicker than the labial side on the maxilla and mandible. In particular, the labial cortical bone thickness in the maxilla was the thinnest compared to the other regions. The cancellous bone thickness according to measurement levels increased from L1 to L5 on the maxilla, and on the mandible it was the thinnest at the middle level of the root. CONCLUSION: For implant placement on the anterior region, a careful evaluation and full knowledge on the thickness of the cortical and cancellous bone are necessary, therefore, these results may provide an anatomic guideline to clinicians.

Angulation between Long Axis of Anterior Teeth and Alveolar Process, and Thickness of Alveolar Bone / 체질인류학회지

The main aim of dental implant placement on the anterior region is to recover the function and esthetics. Therefore, this study examined the angulation between the long axis of the anterior teeth and the alveolar process, and thickness of the alveolar bone on the anterior region. Twenty-five cadaver heads (18 maxillae and 23 mandibles) were examined (16 male and 9 female, mean: 56.7 years). The angulation between the long axis of the anterior teeth and the alveolar process was measured, and the alveolar bone thickness was measured in the three levels (crest; C, middle; M, apex; A) on the labial and lingual sides. All data was analyzed statistically using one-way ANOVA. The maxillary anterior teeth showed two to three times more lingual inclination than the mandibular teeth. The difference in maxillary alveolar bone thickness on the labial and lingual sides was significant in all levels, particularly in the apex. The mandibular alveolar bone thickness on the labial and lingual side was significantly different only in the apex. In conclusion, the alveolar bone thickness on the anterior region was too thin, and the long axis of the maxillary anterior teeth showed more lingual inclination than the alveolar process. Therefore, clinicians need to be a detailed assessment of the labial alveolar bone for dental implant placement.

Angulation between Long Axis of Anterior Teeth and Alveolar Process, and Thickness of Alveolar Bone / 체질인류학회지

The main aim of dental implant placement on the anterior region is to recover the function and esthetics. Therefore, this study examined the angulation between the long axis of the anterior teeth and the alveolar process, and thickness of the alveolar bone on the anterior region. Twenty-five cadaver heads (18 maxillae and 23 mandibles) were examined (16 male and 9 female, mean: 56.7 years). The angulation between the long axis of the anterior teeth and the alveolar process was measured, and the alveolar bone thickness was measured in the three levels (crest; C, middle; M, apex; A) on the labial and lingual sides. All data was analyzed statistically using one-way ANOVA. The maxillary anterior teeth showed two to three times more lingual inclination than the mandibular teeth. The difference in maxillary alveolar bone thickness on the labial and lingual sides was significant in all levels, particularly in the apex. The mandibular alveolar bone thickness on the labial and lingual side was significantly different only in the apex. In conclusion, the alveolar bone thickness on the anterior region was too thin, and the long axis of the maxillary anterior teeth showed more lingual inclination than the alveolar process. Therefore, clinicians need to be a detailed assessment of the labial alveolar bone for dental implant placement.

Morphometric Analysis of the Supraorbital and Infraorbital Foramina Based on the Medial Canthus in Koreans / 체질인류학회지

Knowledge of the location of the maxillo-facial foramina is essential for regional nerve blocks and endoscopic surgical procedures to avoid nerve injury passing through these foramina. The purposes of this study were to determine the locations of the supraorbital foramen (SOF) and the infraorbital foramen (IOF) related to medial canthus (MC), and to analyze the morphology of these foramina. Thirty-two embalmed cadavers (64 sides, mean age: 64.1 years) and 33 dry skulls (66 sides) were used. The distances from the SOF, IOF, and MC to facial midline were directly measured on the cadavers using digital Vernier caliper. The vertical and horizontal distances of the SOF and IOF relative to the medial canthus were indirectly measured on the digital photographs using image analyzer software. The vertical and horizontal diameters of the IOF, and its location in relation to maxillary tooth were evaluated on the dry skull. Statistical analysis was performed using one-way ANOVA with declaration of significant difference when P<0.05. The mean distances of SOF, MC, and IOF to the facial midline were 24.13 mm, 15.00 mm, and 29.11 mm, respectively. The SOF was located 18.99 mm superior and 9.05 mm lateral to the medial canthus. The distance between the medial canthus and the SOF was 22.67 mm, and the vertical angle (Angle 1) between these structures was 24.36degrees superolaterally. The IOF was located 26.69 mm inferior and 13.53 mm lateral to the medial canthus. The distance between the medial canthus and IOF was 30.82 mm and the vertical angle (Angle 2) between these structures was 26.59degrees inferolaterally. In the this study, spraorbital notch (SON) was found more frequently than the SOF. The mean vertical and horizontal diameters of IOF were 3.36 mm, 3.45 mm, respectively. IOF was most commonly found in the same vertical plane with the second upper premolar. In conclusion, these results are important for performing local anesthetic, facial plastic surgery, and other invasive procedures in the forehead and periorbital region to prevent injury of neurovascular bundles passing through these foramina.

Localization of the Mental and Infraorbital Foramen with related to the Soft-tissue Landmarks

During maxillofacial surgery, the infraorbital and mental nerves are blocked at eac foramen to induce local anesthesia. This study examined the relative locations of the infraorbital foramen (IOF) and mental foramen (MF) based on soft-tissue landmarks. Twenty-eight hemifacial cadavers were dissected to expose the IOF and MF. The distances between the bilateral IOFs, the bilateral MFs, the alae of the nose (alares), and the corners of the mouth (cheilions) were measured directly on cadavers by using a digital vernier caliper. The vertical and horizontal distances of the IOF and MF relative to the alare and cheilion were measured indirectly on digital photographs using Adobe Photoshop (Adobe, CA, USA). The distance between the bilateral IOFs (58.09 +/- 4.04 mm) was longer than the distance between the bilateral MFs (50.32 +/- 1.93 mm). The distances between the bilateral alares and cheilions were 41.22 +/- 3.44 mm and 58.43 +/- 6.62 mm, respectively. The IOF was located 12.92 +/- 3.75 mm superior and 7.88 +/- 2.56 mm lateral to the alare, and the vertical angle (Angle 1) between these structures was 31.67 +/- 13.36degrees superolaterally. The MF was located 21.83 +/- 3.26 mm inferior and 5.56 +/- 3.37 mm medial to the cheilion, and the vertical angle (Angle 2) between these structures was 14.05 +/- 10.12degrees inferomedially. In conclusion, these results provide more detailed information about the locations of the IOF and MF relative to soft-tissue landmarks.

Cortical Bone Thickness for Mini-implant Placement in Korean

Recently, mini-implant is popular in the orthodontic treatment due to its simplicity and convenient surgical procedure. The objective of this study is to provide the anatomical guideline for mini-implant placement by analysing the cortical bone thickness in Korean. Hemi-sections of sixteen maxillae and twenty-two mandibles with normal teeth were used. Interdental areas between the 1st premolar and the 2nd premolar (Group 1), the 2nd premolar and the 1st molar (Gruop 2), and the 1st molar and the 2nd molar (Group 3) were sectioned and then scanned. After setting the axis of teeth, the cortical bone thickness was measured at the distance of 2 mm, 4mm, 6 mm, and 8 mm from alveolar crest. The mean thickness of cortical bone in the maxilla according to distance from alveolar crest was 1.30 +/- 0.63 mm (2 mm), 1.49 +/- 0.62 mm (4mm), 1.72 +/- 0.64 mm (6mm), and 1.90 +/- 0.90 mm (8 mm) at the buccal side and 1.33 +/- 0.47 mm, 1.31 +/- 0.45 mm, 1.37 +/- 0.55 mm, and 1.39 +/- 0.58 mm at the palatal side. In the mandible, that was 3.14 +/- 1.71 mm, 4.31 +/- 2.22 mm, 4.23 +/- 1.94 mm, and 4.30 +/- 1.57 mm at the buccal side and 1.98 +/- 0.88 mm, 2.79 +/- 1.01 mm, 3.35 +/- 1.27 mm, and 3.93 +/- 1.38 mm at the lingual side. The buccal cortical bone thickness in the maxilla was decreased from Group 1 to Group 3, while the thickness of palatal side was no change. In the mandible, it did not show a tendency at the buccal side and it was decreased from Group 1 to Group 3 without significant difference at the lingual side. Therefore, the buccal side of the Group 1 and Group 2 in both the maxilla and mandible seems to be the most appropriate site for a mini-implant placement with taking the stability and retention.

Ethanol Extracts of Angelica decursiva Induces Apoptosis in Human Oral Cancer Cells

Angelica decursiva has been used in Korean traditional medicine as an antitussive, an analgesic, an antipyretic and a cough remedy. However, its anti-cancer properties have not yet been well defined. In our current study, we report the cytotoxic activity and the mechanism of cell death induced by ethanol extracts of Angelica decursiva (EEAD) against the human oral cancer cell line, KB. Treatment of KB cells with EEAD induced apoptotic cell death in both a dose- and time-dependent manner as determined by MTT assay and DNA fragmentation. However, no cytotoxic effects of EEAD against human normal oral keratinocytes (HNOK) were evident. By western blot analysis, we found that apoptosis in KB cells is associated with a decrease in procaspase-7 and -9. In addition, the activation of caspase-7 was detectable in living KB cells by fluorescence microscopy. These results suggest that EEAD exhibits anti-cancer activity in KB cells via apoptosis and thus has potential as an anticancer agent in future drug development strategies.

Growth Inhibition of Human Head and Neck Squamous Cell Carcinomas by Angelica decursiva Extracts

Angelica decursiva has been used in Korean traditional medicine as an antitussive, an analgesic, an antipyretic and a cough remedy. However, the anti-cancer properties of Angelica decursiva have not yet been well defined. In our current study the cytotoxic activity of ethanol extracts of Angelica decursiva root (EEAD) and the mechanism of cell death exhibited by EEAD were examined in FaDu human head and neck squamous cell carcinoma cells. The cytotoxic effects of EEAD upon the growth of FaDu cells were examined with an MTT assay. In addition, the mechanism of cell death induced by EEAD was evaluated by DNA fragmentation analysis, immunoblotting and caspase activation measurements. EEAD induced apoptotic cell death in FaDu cells in a concentration- and time-dependent manner, as determined by MTT assay and DNA fragmentation analysis. Furthermore, the proteolytic processing of caspase-3, -7 and -9 was increased by EEAD treatment of FaDu cells. In addition, the activation of caspase-3 and -7 was detected in living FaDu cells by fluorescence microscopy. These results suggest that EEAD can induce apoptosis and suppress cell growth in cancer cells and may have utility as a future anti-cancer therapy.

Morphometric Analysis of Maxillary Sinus Floor and Alveolar Process in Korean / 체질인류학회지

The implant placement and sinus floor elevation on maxillae have required the accurate understanding of maxillary sinus floor and alveolar process. Therefore, the purpose of this study was to investigate the maxillary sinus floor morphology and the correlation between maxillary sinus floor and alveolar process in Korean. Twenty-nine cadaveric maxillae with normal teeth were used, with age at death ranging from 40 to 90 years (mean: 59.9 years). After the maxilla was cut above the nasal cavity floor, it was sectioned at midline of the tooth from 1st premolar to 2nd molar by parallel to long axis of the tooth. The specimens were scanned using the Scanner (HP Scanjet G4050). The scan image was measured using Adobe Photoshop CS3 at the 0.01 mm. Mean, SD, and correlation coefficient (r) were took using SPSS. The width of maxillary sinus floor at nasal cavity floor level was 7.87+/-3.04 mm at 1st premolar (P1), 11.05+/-4.40 mm at 2nd premolar (P2), 13.21+/-4.78 mm at 1st molar (M1), and 12.47+/-4.32 mm at 2nd molar (M2). The depth of maxillary sinus floor at nasal cavity floor level was -3.74+/-4.57 mm, -4.77+/-4.80 mm, -4.84+/-4.69 mm, and -4.19+/-6.24 mm at P1, P2, M1, and M2, respectively. The height of alveolar process bone was 19.02+/-3.36 mm, 15.71+/-4.44 mm, 13.59+/-3.22 mm, and 12.50+/-2.99 mm at P1, P2, M1, and M2, respectively. The correlation coefficient (r) between the width of maxillary sinus floor and the height of alveolar process was 0.342, 0.631, 0.602, and 0.543 at P1, P2, M1, and M2, respectively, which were lack of correlations. The correlation coefficient (r) between the depth of maxillary sinus floor and the height of alveolar process was 0.808, 0.899, 0.789, and 0.805 at P1, P2, M1, and M2, respectively. It represented that the deeper the depth of maxillary sinus floor, the lower the height of alveolar process was. In conclusion, the maxillary sinus floor in Korean was the deepest and the widest at M1, and the height of alveolar process was the lowest at M2. This result provided useful anatomic information about maxillary sinus floor for the implant placement and sinus floor elevation.