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The purpose of this study was to evaluate shear bond strength and microleakage of a new self-etch fissure sealant containing S-PRG filler (BeautiSealant). Fourty-five premolars were randomly divided into three groups: SEPBS group (Self-etching primer + BeautiSealant), AEBS group (Phosphoric acid etching + BeautiSealant), AECP group (Phosphoric acid etching + ClinproTM sealant). For the shear bond strength test, microcylinders of fissure sealant were bonded to prepared buccal surfaces of teeth and shear bond strengths were measured by a universal testing machine. For the microleakage test, sealants were applicated on each occlusal fissure of teeth. All teeth surface were coated with finger nail varnish, with the exception of a 1.0 mm window around the sealant margins. The teeth were immersed in 2% methylene blue solution for 24 hours and then rinsed in water. The teeth were then embedded in resin and cut buccolingually along the tooth axis and observed with a stereomicroscope to determine the degree of microleakage. SEPBS group demonstrated lower bond strength in comparison with that of AEBS and AECP groups (p < 0.05). However, no significant differences were observed between AEBS and AECP groups. There was no statistically significant difference in degree of microleakage among three groups.

To evaluate the oral health status and to assess the resultant dental treatment needs in adolescents, 2,062 adolescents aged 14-17 years attending middle and high schools in Yangsan were surveyed by clinical examination and questionnaires. The obtained results were as follows. In the dental caries examination based on WHO criteria, the treatment needs of 66.7% of the subjects were determined. Assessment of dental erosion by the VEDE system indicated the treatment needs in 27.8% of the subjects, while MIH examination based on EAPD criteria indicated the treatment needs in 14.7%. Assessment of malocclusion using the occlusal index showed good occlusion in 67.8%, no need for treatment in 19.7%, slight need for treatment in 6.8%, definite need for treatment in 4.5%, and worst occlusion in 1.1% of the subjects, showing 12.5% of average treatment need. The prevalence and treatment need for periodontal disease was found to be 71.2% by CPITN assessments. The assessment of temporomandibular disorders by Helkimo’s anamnestic index showed no symptoms in 67.1%, mild symptoms in 13.4%, and severe symptoms in 19.5% of the examinees. The overall treatment need of TMD was 20.6%. Periodontal diseases were ranked the highest in treatment need, followed by dental caries, dental erosion, MIH, TMD, and malocclusion in order. The results of this study indicated the overall status of adolescents’oral health and dental treatment needs. These might hopefully provide fundamental data and contribute to establishing promotional projects for adolescent oral health in Korea.

Composites are the most useful restorative material. However, composites have some disadvantages such as polymerization shrinkage, long working time, and susceptibility to water and contamination, which are stood out more especially when treating children. To solve these problems, bulk-fill composites have been developed. The aim of this study is to compare mechanical properties of bulk-fill and conventional composites. Bulk-fill composites (SureFil SDR flow (SDR), Tetric N-Ceram bulk fill (TBF)) and conventional composites (Filtek Z-350 (Z-350), Unifil Flow (UF), Unifil Loflo Plus (UL)) were used. The Vickers hardness tester was used to measure the microhardness of materials, and Fourier transform infrared spectroscopy was used to measure the degree of conversion. Polymerization shrinkage was measured by using a linometer. Flexural and compressive properties were measured by using the universal testing machine. Data were statistically analyzed by ANOVA and Scheffe’s post hoc test. The level of significance was set to p < 0.05. Most conventional composites showed higher microhardness than bulk-fill composites. However, bulk-fill composites showed a higher top/bottom microhardness ratio than conventional composites. Bulk-fill composites showed a higher top/bottom degree of conversion ratio than conventional composites. The polymerization shrinkage was highest in UL and lowest in Z-350. The polymerization shrinkage of flowable composites was higher than that of non flowable composites. The compressive properties were highest in Z-350 and lowest in SDR and UL. In terms of flexural properties, Z-350 was the highest. However, none of the bulk-fill composites exhibited mechanical properties as good as those of conventional composites. Nonetheless, the ratio of microhardness and degree of conversion, which are important properties of bulk filling, were higher in bulk-fill composites. Therefore, the bulk-fill composites might be considered suitable restorative materials in pediatric dentistry.

The purpose of this study is to compare the effectiveness of sonic and manual toothbrushes using the Löe and Silness plaque index (PI). This was an examiner-blind, randomized study with a cross-over design. A total of 34 children (17 males and 17 females) aged 3-6 years were included. Subjects were randomly assigned to two groups: one group used the sonic brush for two weeks before using the manual brush for two weeks, while the other group used the manual brush for two weeks followed by the sonic brush. During each dental visit, plaque indices were recorded and compared to baseline. The results were analyzed using a paired t-test or Pearson correlation test (α= 0.05). Thirty children (mean age 4.37 years) complied with the protocol and completed the study. The PI score was 0.09 lower compared to baseline after using a manual toothbrush and 0.26 lower after using the sonic brush. The reduction was statistically significantly greater in the sonic group (p < 0.05). In conclusion, the sonic toothbrush is more effective for reducing plaque than a manual toothbrush.

Since it is favorable to include the incipient caries lesion in the diagnostic criteria in adolescence, this study had surveyed dental caries status of adolescents at ages of 13 and 16 by using WHO basic methods and ICDASII codes. In this study, mean DMFT index was 3.71, and mean DT index was 1.94. For both indices, the age 16 group showed higher values than the age 13 group. By groups of teeth, DMFT index and DT index exhibited highest to the lowest values in molar, premolar, and anterior teeth, respectively. 77.46% of total numbers of teeth were classified as code 0 in ICDAS-II. Compared to anterior teeth, numbers of decayed teeth were increased in posterior teeth. All caries lesions in anterior teeth and premolars were limited to enamel. ICDAS-II code is an useful method to detect the incipient caries lesion, allowing preventive control on caries management.

The purpose of this study was to evaluate the difference of remineralization effects of various anti-cariogenic toothpastes on artificial carious lesions in primary and permanent teeth using quantitative light-induced fluorescence- digital (QLF-D) system. Sound human primary (n = 48) and permanent teeth (n = 48) were randomly divided into following groups : control group (Group 1), fluoride toothpaste (Group 2), functionalized tricalcium phosphate (fTCP) + fluoride toothpaste (Group 3), and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) toothpaste (Group 4). Specimens were prepared by exposure in a demineralizing solution and then treated using the different toothpastes twice daily during 14 days. All specimens were analyzed with the QLF-D system. QLF data analysis indicated three different toothpastes showed significant remineralizing effects compared to Group 1 in both primary and permanent teeth. Also, the remineralizing effects in Group 3 and 4 were significantly higher than in Group 2. This study suggested that the toothpastes containing fTCP + fluoride and CPP-ACP have the significant anti-cariogenic effects on enamel demineralization in both primary and permanent teeth, and QLF-D is an useful device to assess the incipient carious lesion and remineralization effects of the anti-cariogenic materials quantitatively. Therefore, clinicians can consider the QLF-D system for the evaluation of demineralization and remineralization in primary and permanent teeth.

This research investigates into overall oral health status of adolescent girl inmates in a juvenile detention facility and ordinary school students in the same age range of 11 to 18 years old and compares the results focusing on the difference between the two groups. The last 5 years dental records for girl inmates in Juvenile detention facility and for students who have visited the Department of Pediatric Dentistry at Ajou University Hospital was colleted and analyzed. The restorative treatments took up the greatest part in their history of treatments. While the percentage of extractions of permanent teeth due to dental caries had been gradually increased, in Juvenile detention facility students, throughout the transition period from middle school to high school, in dental hospital patients, the phenomenon of the same kind has hardly been detected. After that record analysis, oral examination for Juvenile detention facility students and dental hospital patients was conducted. DMFT index for dental hospital patients are 4.15, whereas, the value for Juvenile detention facility students are as twice as high to be 7.53.

This study examined the prevalence of MIH and severity of hypomineralization exhibited by MIH-affected tooth based on the clinical examination of 950 children between age 8 and 9 in the city of Jeonju. The etiology was also studied utilizing a questionnaire on the MIH risk factors. The prevalence of MIH was 7.1%. The examined MIH-affected teeth showed statically significant difference in the degree of their hypomineralization (p < 0.05). The permanent first molar showed greater frequency of MIH compared to the permanent incisor, and the MIH code 2a and 3 were only observed in the permanent first molar (p < 0.05). From the questionnaire, showed the significant relationship between the occurrence of MIH and risk factors such as stress and antibiotics intake during pregnancy, low birth weight and events like hospital admission, frequent respiratory infection, high fever and long-term antibiotics intake within the three years of children’s lives (p < 0.05). Among all the possible risk factors, the antibiotics intake during pregnancy only showed high correlation with the incidence of MIH (p < 0.05).

For this research 20 supernumerary teeth impacted in the maxillary anterior have been extracted and pulp cells have been collected from them. From the collected pulp cells, total of 17 (10 males, 7 females) have been selected as subjects. From this research, the run-time of successive culture of the cell from tooth number pulp tissue was 2.91 ± 0.29 days. From the gathering of cells from the initial pulp tissue until gaining 80% confluency took 4.53 ± 0.94 which was the longest. The following successive cultures took 2.73 ± 0.32 days. Average runtime for female was 2.81 ± 0.27 days whereas male had average runtime of 2.98 ± 0.29 days. Average run-time for inversion was 2.94 ± 0.30 days and for normal location, 2.80 ± 0.20 days. Average runtime was 2.92 ± 0.31 days and other forms took 2.88 ± 0.22 days. In the future, follow up research would be needed to evaluate the efficiency of the cells collected from the initial passage and the latter passage as stem-cells and taking into consideration the less than 3 days’time for the subculture, it could be concluded that the research efficiency and fast cultivation would be sufficiently effective.

The aim of this study was to compare the mechanical properties of high viscosity bulk-fill resin composites, FiltekTM Bulk Fill Posterior Restorative (FBF) and Tetric􀋓 N-Ceram Bulk Fill (TBF), with conventional composite (FiltekTM Z-350 XT, Z-350). The Vickers hardness test which indicates the degree of conversion was performed and the dye penetration test was performed to measure the microleakage which indicates polymerization shrinkage amount. To minimize experimental error, the standardized 3D-printed molds and the bovine teeth were used. Obtained data were analyzed by the Kruskal-Wallis test and Mann-Whitney test with the confidence interval of 95%. In the microhardness test within 1 hour of polymerization, lower surface of FBF and TBF showed significantly lower value than that of Z-350 (p < 0.05). But after 24 hours, the microhardness of FBF had increased and showed no significant difference with Z-350 (p > 0.05). In top and 2 mm depth surface, mean microhardness values were in the following order: Z-350 > FBF > TBF (p < 0.05). The mean microleakage value of TBF was significantly lower than others (p < 0.05). For clinical application of bulk-fill resin composites, caution for applying masticatory forces during 24 hours after polymerization is advised and further studies to decrease microleakage should be conducted.

The aim of this study was to analyze physiological changes, clinical and subjective symptoms by different N2O concentrations and administration method. This study surveyed 65 men and women ages 19 to 35 and all subjects were healthy volunteers, with no contraindication for use of N2O sedation. The N2O sedation was carried out in a way that increases by 10 percent to one-minute interval or increases at once the desired level. Each method was required to reach 30 or 50 percent N2O concentration. The way to gradually raise the N2O concentration can reduce the risk by decreasing the pulse reduction rate at the same N2O concentration. SpO2 has no statistical significance according to N2O concentration and method of administration. Pulse rate reduced significantly when 50% N2O increase at once during sedation and 100% O2 after 5 minutes. The way to gradually raise the N2O concentration is safe for reducing pulse rate.

Subjects of this study were : FluoroDose􀋓 (FD, Centrix Inc., USA), EnamelastTM (EL, Ultradent Product Inc., USA), ClinproTM white varnish (CW, 3M ESPE, USA), CavityShieldTM (CS, 3M ESPE, USA), V varnishTM (VV, Vericom, Korea), MI varnishTM (MI, GC, Japan). The amount of fluoride ion release was measured eight times during 168 hours to see change in accumulation with the course of time using a measuring instrument. And the remineralization rate was measured with Quantitative Light-induced Fluorescence (QLF). V varnishTM group and MI varnishTM group showed high remineralization rates with statistically significance while CavityShieldTM group was the lowest rate of remineralization (p < 0.05). After that, several chosen samples were scanned through electron microscope (SEM). Demineralized enamel was observed as the number of enamel crystal was very small; enamel rods and crystals were highly protruding. Remineralized groups with fluoride varnishes show the decreasing tendency of the surface roughness compared to the demineralized enamel.

Burkitt lymphoma (BL) is an aggressive form of non-Hodgkin’s B-cell lymphoma found primarily in the pediatric population. In the oral cavity, this tumor can grow rapidly and often brings about facial swelling or development of an exophytic mass involving the jaws. A 5-year-old boy was referred for swelling and pain in the left mandibular area. The patient showed diffuse swelling on the left side of the mandible and firm-moderate tenderness upon palpation. An intraoral examination showed moderate mobility and sensitivity to percussion on the left primary first and second molars, without severe caries. A radiographic examination revealed complete loss of the lamina dura on the left primary second molar and permanent first molar. There was a radiolucent osteolytic lesion and destruction of the cortical bone of the left mandibular body. Based on the clinical, radiographic, and immunohistochemical findings, the patient was diagnosed with BL, and was referred to a pediatrician for systemic evaluation and intensive chemotherapy. Even before the completion of chemotherapy, the swelling resolved and the displaced teeth were relocated to a normal position. This patient showed a good prognosis due to prompt diagnosis and intensive chemotherapy. Early diagnosis and referral for treatment can prevent the development of BL.

Dental caries is an important dental disease among children and adolescents that can continue for a lifetime. Early detection of dental caries in deciduous dentition is significant because it can influence the permanent teeth. It is also critical to prevent dental caries by performing fluoride treatment and pit-and-fissure sealant for high-risk children. Various methods have been developed for the early detection of dental caries; however, many studies are still seeking to discover more effective methods. In general, visual examination and radiographic images are used, but these techniques have several limitations such as errors and radiation exposure. In this study, clinical application of the newly developed DIAGNOcam caries identification device and its possible applications were examined. DIAGNOcam was applied to diagnose dental caries in the posterior teeth of patients in the Department of Pediatric Dentistry, and it was confirmed that it could be used to detect proximal caries, the margin of restoration, and the extent of dental caries lesions.

Successful root canal treatment can be obtained by the removal of microorganisms from the pulpal space of the root canal system through biomechanical technique with instruments and irrigation. Due to the difference in the dimension of the pulpal structure such as thin wall of the root, large portion of chamber, the primary teeth should be considered in a different way of approach. Traditionally, fluids have been dispensed passively into the root canals for improve the cleansing. The use of sodium hypochlorite as an irrigant in root canal treatment is widespread and common, because it meets requirements for the ideal irrigants.

In connection with medical care, designs have been developed by forming relationships, typically supporting Visual Communication Design, Product Design and Environment Design healthcare environment aesthetically pleasing and convenient. However, in recent designs, expertise has increased, new areas specialized are merged with various areas and academic disciplines and subdivided. In addition, due to the development of technology, the design has been continuously changing, creating a new form of model by fusing with various industries, academics and services. Recognizing the changes and developments of these designs, we are promoting research on utilization of design in medical services, we can create a new value by getting out of design that we have limitedly used in areas of traditional design I will try to know about developing into a design.