The aim of this study was to investigate the role of osteal macrophages (osteomac) and osteocytes in bone remodeling using a mathematical model. We constructed the bone system with pre-osteoblasts, osteoclasts, osteocytes, and osteomac. Each link of the parameters and ordinary differential equations followed the Graham's model in 2013 except for the parameters of osteomac signaling and osteocytes signaling to link preosteoblasts and osteoblasts. We simulated the changes in each cell and bone volume according to the changes in the parameters of osteomac signaling and osteocytes signaling. The results showed bone volume was unstable and decreased gradually when the effectiveness of osteocytes and osteomac dropped below a certain level. When the parameters of osteomac signaling and osteocytes signaling to link preosteoblasts and osteoblasts had a value less than 1, bone volume increased with the increase in the parameter of osteomac signaling to link preosteoblasts and osteoblasts. Moreover, although the parameter of osteocytes signaling to link preosteoblasts and osteoblasts, increased in case of a small parameter of osteomac signaling, bone volulme decreased. If the parameters of osteomac signaling to link preosteoblasts and osteoblasts were over a certain level, bone volume was positively maintained, despite the parameter of osteocyte signaling to link preosteoblasts and osteoblasts. We suggested the osteomac may affect bone remodeling and may play an important role in bone cell network.
Bone and Bones* ; Bone Remodeling ; Macrophages* ; Models, Theoretical* ; Osteoblasts ; Osteoclasts ; Osteocytes*

The purpose of this study was to examine the association between the symptoms of temporomandibular joint disorders and lumbar diseases in adults when the prevalence rate of osteoarthritis is increasing and to help develop health policies that can improve oral health and health in general. The study used representative data from the 5th Korea National Health and Nutrition Examination Survey phase 3 (2012). In total, we analyzed the data of 3,017 individuals aged over 50 years who participated in the health-related survey and underwent radiography of the lumbar joints. PASW statistics ver. 18.0 was used for analysis. This study revealed the following results: 16.1% experienced at least one symptom of temporomandibular joint disorders within the recent single year, 20.6% experienced lower back pain in the recent three months, and 30.6% had lumbar osteoarthritis revealed using radiography of the lumbar joints. Symptoms of temporomandibular joint disorders, lower back pain, and lumbar osteoarthritis were correlated with each other; the respondents who experienced symptoms of temporomandibular joint disorders had 1.70 times (95% confidence interval [CI], 1.30∼2.22) higher prevalence of lower back pain and 1.20 times (95% CI, 0.86∼1.68) higher prevalence of lumbar osteoarthritis than in those with no such difficulties. The results of this study confirmed that the symptoms of temporomandibular joint disorders affected lumbar diseases in adulthood. Therefore, adequate treatment and prevention of the symptoms of temporomandibular joint disorders in adults is expected to make crucial contributions to decreases in the prevalence rate of lumbar diseases and an improvement in the quality of life.
Adult* ; Health Policy ; Humans ; Joints ; Korea ; Low Back Pain ; Nutrition Surveys ; Oral Health ; Osteoarthritis ; Osteoarthritis, Spine ; Prevalence ; Quality of Life ; Radiography ; Surveys and Questionnaires ; Temporomandibular Joint Disorders* ; Temporomandibular Joint*

The purpose of this study to review clinicians and educators on required communication education factors of dental hygienists using qualitative research by focus group interview. The participants were dentists, dental hygienists and professors. A questionnaire was developed on communication education to collect data. The collated data derived concepts related to communication education. After transferring the data, were analyzed by open coding and axial coding using computer-aided qualitative data analysis software. Focus group emphasized that higher education on communication should be preceded before they are put into the clinical field. However, the dental hygienist emphasized experiential education in the clinical field, the professor emphasized additional education for continuity of communication education even after graduation. Besides, focus group emphasized role play, and the professor required that the standardization of the dental communication training courses objectives and role play modules and the education environment infrastructure should be established to implement communication education efficiently. The categories of communication education stated in the focus group were time and method for the dental communication training courses, dental communication training courses standardization and educational environment, of evaluation of communication competency, of perception of the dental communication training courses. This study identified the communication education development to conform with the needs of the clinical field strengthen and cultivate communication competency dental hygienists based on factors of communication education emphasized in focus groups.
Clinical Coding ; Dental Hygienists* ; Dentists ; Education* ; Focus Groups* ; Humans ; Methods ; Qualitative Research* ; Statistics as Topic

The purpose of this study was to focus on the number of brushing strokes among the performance factors and identify if the 10 times stroke of the rolling method is rational. Moreover, we evaluated the changes in oral health knowledge, perception, and behavior after our rolling method instruction. The 10-stroke method of toothbrushing has been regarded as an effective method of removal of dental plaque, although there is little evidence to support this claim. We allocated 40 healthy subjects to two intervention groups. During five visits, we measured a score for dental plaque removal and instructed the subjects on a toothbrushing technique with 5 or 10 strokes per section. At the initial and final visits, subjects completed a questionnaire on one designed specifically for this study about oral health knowledge, perceptions, and behaviors. Repeated measures analysis of variance was used to compare the dental plaque removal score between the groups, and the changes in scores within each group over time. We also compared changes in mean scores in oral health knowledge, perceptions and behaviors before and after toothbrushing instruction. We found that the score for dental plaque removal increased with each additional toothbrushing instruction in both groups (p < 0.001). However, we found no differences in the dental plaque removal scores between the 5-stroke and 10-stroke groups (p=0.399). The levels of oral health knowledge, perceptions and behaviors increased after the toothbrushing instructions in both groups. Our findings suggest that there is no advantage in emphasizing the 10-stroke method of toothbrushing in an oral health education program.
Dental Plaque ; Education* ; Health Education ; Healthy Volunteers ; Methods ; Oral Health ; Stroke* ; Toothbrushing*

The purpose of this study was to classify risk groups according to Caries Risk Assessment (CRA) and to investigate the effect of caries prevention program after 1 year of caries prevention intervention program in 6-year-old infants with high caries risk. The subjects were selected based on responses to CRA questionnaires. At the first visit, oral examination, Cariview, bacteria and saliva flow test were performed. The caries risk group was classified accordingly. The subjects were given fluoride application and oral health education every four months and evaluated the same as the first visit after 1 year. As a result of classifying the risk level according to CRA, more than 80% of the subjects were in the high or extreme high risk. The dft index was increased in all risk groups after the intervention. There was a significant difference between the before and after intervention (p < 0.05). The Cariview score showed a slight decrease after the intervention in the moderate and high risk groups. As a result of the evaluation of bacteria test, Streptococcus mutans were decreased to ≥10⁵ CFU/ml saliva after intervention in all groups. Lactobacilli were decreased after intervention in high risk and extreme high risk groups. As a result of saliva flow, there was significant difference between caries risk groups before and after intervention (p < 0.05). In conclusion, regular caries management has been shown to influence caries risk factors in high-caries risk children. Also, it is necessary to find out periodical dental risk management system which is suitable for domestic situation through the related studies.
Bacteria ; Child* ; Diagnosis, Oral ; Education ; Fluorides ; Humans ; Infant ; Oral Health ; Risk Assessment* ; Risk Factors ; Risk Management ; Saliva ; Streptococcus mutans

The purpose of this study is to propose learning objectives in social dental hygiene by analyzing and reviewing learning objectives in oral health administration area of the existing public oral health. This study is a cross-sectional study. The subjects of the study selected with convenience extraction were 15 members of the social dental hygiene subcommittee of the Korean Society of Dental Hygiene Science. Data collection was conducted by self-filling questionnaire. The research tool is from 48 items of A division in the book of learning objectives in the dental hygienist national examination, and this study classified each of them into ‘dental hygiene job relevance’, ‘dental hygiene competency relevance’, ‘timeliness’, and ‘value discrimination of educational goal setting’ to comprise 192 items. Also, to collect expert opinions, this study conducted Delphi survey on 7 academic experts. Statistical analysis was performed using the IBM SPSS Statistics ver. 23.0 program (IBM Co., Armonk, NY, USA). Recoding was performed according to the degree of relevance of each learning objective and frequency analysis was performed. This study removed 18 items from the whole learning objectives in the dental hygienist national examination in the oral health administration area of public oral health. Fifteen revisions were made and 15 existing learning objectives were maintained. Forty-five learning objectives were proposed as new social dental hygiene learning objectives. The topics of learning objectives are divided into social security and medical assistance, oral health care system, oral health administration, and oral health policy. As a result of this study, it was necessary to construct the learning objectives of social dental hygiene in response to changing situation at the time. The contents of education should be revised in order of revision of learning objectives, development of competency, development of learning materials, and national examination.
Cross-Sectional Studies ; Data Collection ; Dental Hygienists ; Discrimination (Psychology) ; Education ; Expert Testimony ; Humans ; Hygiene ; Learning* ; Medical Assistance ; Oral Health* ; Oral Hygiene* ; Social Security

Wet wipes are being increasingly used because of their convenience. Particularly, oral wet wipes are useful for regular cleaning of a baby's mouth after birth. Therefore, the consumption of oral wet wipes has increased over the past few years and a variety of products are commercially available. However, product information on safety is not sufficiently provided and still raises doubts regarding adverse effects. To confirm the safety of wet wipes as an oral hygiene item and provide information for their use, we investigated the cytotoxicity of oral wet wipes and verified the underlying mechanism. The anti-bacterial effect of oral wet wipes was analyzed using the disk diffusion method. The cytotoxic effects of oral wet wipes were observed based on morphological changes using microscopy and determined using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in gingival epithelial cells and gingival fibroblasts. Evaluation of apoptosis by oral wet wipes was explored using propidium iodide flow cytometric analysis and a terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) nick-end labeling (TUNEL) assay. Apoptosis-related molecules were also analyzed using western blotting. Five types of oral wet wipes were tested, and two products from Fisher-Price and Dr. Kennedy revealed strong cytotoxic effects on gingiva epithelial cells and gingiva fibroblasts, although they also showed intense anti-bacterial effects on oral bacteria. Cell cycle arrest in the G2/M phase and apoptosis were observed based on treatment of extracts from Fisher-Price and Dr. KENNEDY. Relatively high TUNEL levels, reduction of proliferating cell nuclear antigen and cyclin-dependent kinase 4 expression, and fragmentation of poly (ADP-ribose) polymerase were also elucidated. These results suggest that commercial oral wet wipes could exert cytotoxic influences on oral tissue, although there are anti-bacterial effects, and careful attention is required, especially for infants and toddlers.
Apoptosis ; Bacteria ; Blotting, Western ; Cell Cycle ; Cell Cycle Checkpoints ; Cell Survival ; Cyclin-Dependent Kinase 4 ; Deoxyuridine ; Diffusion ; DNA Nucleotidylexotransferase ; Epithelial Cells ; Fibroblasts ; Gingiva ; Humans ; In Situ Nick-End Labeling ; Infant ; Methods ; Microscopy ; Mouth ; Oral Hygiene ; Parturition ; Proliferating Cell Nuclear Antigen ; Propidium

The purpose of our study is to compare the adhesion and biofilm formation abilities of isolates from water discharged from dental unit waterlines (DUWLs). Bacteria were isolated from a total of 15 DUWLs. Twelve isolates were selected for the experiment. To confirm the adhesion ability of the isolates, each isolate was attached to a glass coverslip using a 12-well plate. Plates were incubated at 26℃ for 7 days, and the degree of adhesion of each isolate was scored. To verify the biofilm formation ability of each isolate, biofilms were allowed to form on a 96-well polystyrene flat-bottom microtiter plate. The biofilm accumulations of all isolates formed at 26℃ for 7 days were identified and compared. A total of 56 strains were isolated from 15 water samples including 12 genera and 31 species. Of the 56 isolates, 12 isolates were selected according to the genus and used in the experiment. Sphingomonas echinoides, Methylobacterium aquaticum, and Cupriavidus pauculus had the highest adhesion ability scores of +3 among 12 isolates. Among these three isolates, the biofilm accumulation of C. pauculus was the highest and that of S. echinoides was the third-most abundant. The lowest biofilm accumulations were identified in Microbacterium testaceum and M. aquaticum. Most isolates with high adhesion ability also exhibited high biofilm formation ability. Analysis of adhesion and biofilm formation of the isolates from DUWLs can provide useful information to understand the mechanism of DUWL biofilm formation and development.
Bacteria* ; Bacterial Adhesion ; Biofilms* ; Cupriavidus ; Glass ; Infection Control, Dental ; Methylobacterium ; Polystyrenes ; Sphingomonas ; Water ; Water Microbiology

Early childhood caries is a widespread condition that requires attention; however, its treatment remains a challenge in terms of child behavior management. This study describes the usefulness of customized zirconia crowns for the restoration of deciduous teeth through the evaluation of some cases. Three cases are described: a 29-month-old girl who presented with severe early childhood caries affecting anterior tooth, a 50-month-old boy who presented with extensive caries of his anterior tooth, and 70-month-old girl who presented with extensive caries of his primary posterior dentition. These prefabricated, zirconium-based ceramic crowns (Nusmile™ NuSmile) are available in various sizes, shapes and colors. Before the treatment, radiographs and intraoral photographs were taken to evaluate the appropriateness of treatment. Our findings indicate that customized zirconia crowns may be appropriate for restoring the deciduous teeth. Further long-term clinical studies are required to clarify the usefulness of this restorative method.
Ceramics ; Child Behavior ; Child* ; Child, Preschool ; Crowns* ; Dental Caries ; Dentition ; Female ; Humans ; Male ; Methods ; Pediatric Dentistry ; Tooth ; Tooth, Deciduous*

The aim of the current study was to demonstrate the potential therapeutic efficacy of resveratrol in oral cancer patients. Lysophosphatidic acid (LPA) intensifies cancer cell invasion and metastasis, whereas resveratrol, a natural polyphenolic compound, possesses antitumor activity, suppressing cell proliferation and progression in various cancer cell lines (ovarian, gastric, oral, pancreatic, colon, and prostate cancer cells). In addition, resveratrol has been identified as an inhibitor of LPA-induced proteolytic enzyme expression and ovarian cancer invasion. Furthermore, resveratrol was shown to inhibit oral cancer cell invasion by downregulating hypoxia-inducible factor 1α and vascular endothelial growth factor expression. Recently, we demonstrated that LPA is important for the expression of transcription factors TWIST and SLUG during epithelial-mesenchymal transition (EMT) in oral squamous carcinoma cells. In this study, we treated serum-starved cultures of oral squamous carcinoma cell line YD-10B with resveratrol for 24 hours prior to stimulation with LPA. To identify an optimal resveratrol concentration that does not induce apoptosis in oral squamous carcinoma cells, we determined the toxicity of resveratrol in YD-10B cells by assessing their viability using the MTT assay. Another assay was performed using Matrigel-coated cell culture inserts to detect oral cancer cell invasion activity. Immunoblotting was applied for analyzing protein expression of SLUG, TWIST1, E-cadherin, and GAPDH. We demonstrated that resveratrol efficiently inhibited LPA-induced oral cancer cell EMT and invasion by downregulating SLUG and TWIST1 expression. Therefore, resveratrol may potentially reduce oral squamous carcinoma cell invasion and metastasis in oral cancer patients, improving their survival outcomes. In summary, we identified new targets for the development of therapies against oral cancer progression and characterized the therapeutic potential of resveratrol for the treatment of oral cancer patients.
Apoptosis ; Cadherins ; Carcinoma, Squamous Cell ; Cell Culture Techniques ; Cell Line ; Cell Proliferation ; Colon ; Epithelial-Mesenchymal Transition ; Gastropoda ; Humans ; Immunoblotting ; Lysophospholipids ; Mouth Neoplasms* ; Neoplasm Metastasis ; Ovarian Neoplasms ; Prostatic Neoplasms ; Stilbenes ; Transcription Factors ; Vascular Endothelial Growth Factor A