cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.14457/cu.the.2017.169
title: EVALUATION OF PUSH OUT BOND STRENGTH OF GLASS FIBER POST RELATED WITH ULTRASONIC IRRIGATION

description: Objective This study compared the bond strength of glass fiber post to dentin using different irrigation methods and solutions and to evaluate the bond strength in different regions of the root. Methods One hundred human anterior maxillary teeth were randomly divided into 10 groups (n=10). Root canal filling and post space preparation were carried out followed by diverse final irrigation techniques. Groups 1 to 3 underwent syringe irrigation, groups 4 to 6 irrigation with ultrasonic instrumentation and groups 7 to 9 passive ultrasonic irrigation. Different irrigant solutions were used in each groups as 2.5% NaOCl (groups 1,4,7), 17% EDTA (groups 2,5,8) and 2.5% NaOCl followed by 10% sodium ascorbate (groups 3,6,9). Group 10 was done by syringe irrigation with distilled water. Fiber post luting was performed with Panavia SA Cement Plus. Slices of 1 mm thickness were divided into cervical and apical root regions. Push-out bond strength tests were performed. Results Bond strengths were significantly affected by different irrigants (p&lt;0.05; 2-way ANOVA). Irrigant solution groups 3, 6, and 9 with NaOCl followed by sodium ascorbate gave higher bond strengths with group 6 showing a significant difference between cervical and apical root regions. Conclusions Bond strengths are significantly affected by different irrigant solutions. An irrigant solution of NaOCl followed by sodium ascorbate resulted in high bond strength values. The region of the root was affected only in group 6.
DOI: 10.14457/cu.the.2017.170
title: Microleakage of enamel preservation at gingival wall of class ii resin composite restorations (nanofilled vs bulk-fill)

description: Objectives. This in vitro study tested the hypothesis that preserving a thin enamel layer at the gingival margin and using bulk-fill resin composites could minimize microleakage of class II resin composite. Materials and Methods. Thirty-six human third molars were randomly divided into three groups of 12 specimens each: Filtek Bulk Fill Posterior Restorative in Capsules (BFC), Filtek Bulk Fill Posterior Restorative in Syringes (BFS) and Filtek Z350 XT (Z350). Teeth were prepared on two sides for a class II cavity (3 mm buccolingually x 2 mm mesiodistally at occlusal and 1.5 mm at coronal x 4 mm of axial depth) with 0.5 mm under the CEJ on one side (NP) and 0.5x1 mm of thin enamel at the gingival margin was preserved on the other side (EP). The teeth were then restored, thermocycled, immersed in 0.5% methylene blue solution for 24 hours and sectioned mesiodistally through the restorations. Dye penetration was evaluated at the gingival margin by three blinded examiners using a 0-4 ordinal scale. The Kruskal-Wallis test and Dunn test were used to compare differences in microleakage scores among the three restorative materials. Mann-Whitney U test was utilized to analyze the difference between enamel preserved (EP) and non-enamel preserved sides (NP) in the same restorative material. Tests were performed with the level of significance at a = 0.05. Results. Mann-Whitney U test showed that the “NP” groups had significantly higher microleakage score than the “EP” groups. The Kruskal-Wallis test revealed significant differences in microleakage scores among the three restorative materials (P &lt; 0.05). Compared to “Z350”, the “EP” group, “BFC” and “BFS” had significantly less microleakage score (P = 0.001) (P = 0.028). The “NE” group, “BFC” had significantly less microleakage score than “Z350” (P = 0.001). Conclusions. Preserving thin layer of enamel (“EP”) and use of two bulk-fill products (“BFC” and “BFS”) reduced microleakage of class II resin composite.
DOI: 10.14457/cu.the.2017.171
title: PATIENT’S PERCEPTION AND SATISFACTION ON DENTAL IMPLANT THERAPY BY POSTGRADUATE DENTAL STUDENTS AND EXPERIENCED DENTISTS

description: Objective: To evaluate and compare patient’s perception and satisfaction between patients who received dental treatment from postgraduate dental students and experienced dentists. Material and methods: This descriptive cross-sectional study was performed in patients who received the dental implant from Faculty of dentistry Chulalongkorn University. A data collection of patient’s perception and satisfaction was done by questionnaire which was sent by mail. The questionnaire contained 23 statements including 7 statements of demographic data, 7 statements of perception, and 9 statements of satisfaction. The patient had to answer through the one-best-answer multiple choices and visual analog scale (VAS). Results: The 382 participants showed that the main implant information source was dentist (n=213, 55.8%). Ninety percent of the participants got well informed about dental implant and satisfied with chewing function, phonetics aspect and esthetic appearance of dental implant. However, an inappropriate perception was illustrated. For example, eighteen percent of the participant agreed with the statement “Dental implants require less care than natural teeth”. About thirty-five percent of participants agreed with the statement “Dental implants last longer than natural teeth”. Seventy-five percent of participants agreed with the statement “Treatment with dental implants have no risk or complication”. Furthermore, half of the participants agreed with “The cost of dental implant therapy is appropriate”. Participants who got treatment from the experienced dentist rated higher score in “I am well informed with dental implants treatment” and “Dental implants look as nice as natural teeth” (p=0.029 and p=0.004, respectively). Conclusion: Most participants had an appropriate perception and a high satisfaction after dental implant treatment. However, the information about the potential complications of dental implant was inadequate. Moreover, half of the participants reported unreasonable cost of dental implant. Despite the expertise levels of dental implant treatment were different, most participants had similar level of satisfaction. They also had similar level of perception in most aspect; however, participants who underwent dental implant treatment from experienced dentist had better information and more natural looking teeth than those who got treatment from postgraduate dental student.
DOI: 10.14457/cu.the.2017.172
title: The inflammatory response of epithelial cell to corrosion products from recast palladium –silver alloy

description: In dentistry, there is an increase in alternative metals such as palladium or silver to add into noble metal alloys in order to improve properties and reduce cost. Apart from using other metals to replace gold or platinum, reuse is another way to save the cost. There are many studies on the recast dental alloys on mechanical properties and how many percentages of new alloys needed to add in the recasting process. It has been well accepted that amount of new and used alloys would affect the mechanical and physical properties. The biocompatibility of the alloys, however, has not been extensively investigated. It is reported that metal ions releasing from recasting alloys, might influence on the biocompatibility of the alloy, but the mechanisms is not yet clear. In the gingival sulci, the metal restoration margin is in close proximity to the sulcular epithelium, therefore the epithelial cells may encounter the released metal ions as an external stimulus. To investigate the epithelial inflammatory responses to corrosion products from recast palladium-silver alloy. Three specimens of each group from first cast, second cast and fourth cast Pd-Ag alloy (10*5*1mm3) were submerged in artificial saliva for 15 days. Microstructure of alloys were observed by a scanning electron microscope (SEM). The corrosion products from alloys were measured by an inductively coupled plasma mass spectrometry (ICP). To study the biocompatibility property, the oral epithelial cells cultured in monolayer were challenged by corrosion product from recast alloys. Quantitative RT-PCR was used to examine the expression of proinflammatory cytokines-specific mRNA, including IL-1β and TNF-α. Microstructure were changed after recasting. Palladium ion was more found after recast. In a reverse transcriptase PCR, IL-1β mRNA levels in response to corrosion product of second and fourth recast group were significantly higher than first cast group. We suggest that the corrosion product from recast Pd-Ag alloy induce epithelial cells to secrete IL-1β which is a proinflammatory that is also found in inflammed gingival tissue. This research give more information and understanding on biocompatibility of recast palladium-silver alloy by observing their corrosion behavior and potential cytotoxic effect i.e. presence of inflammatory response.
DOI: 10.14457/cu.the.2017.173
title: THE LONGEVITY OF CERAMIC VENEERS: CLINICAL EVALUATION OF MECHANICAL, BIOLOGICAL, AND ESTHETIC PERFORMANCES OF CERAMIC VENEERS UP TO 7-YEARS RETROSPECTIVE STUDY

description: Purpose: To evaluate the longevity and mechanical, biological and aesthetic performance of ceramic veneers placed after 5 to 7 years in service. Materials and Methods: Ceramic veneer restorations were clinically examined following modified from the United States Public Health Service (USPHS) and World Dental Federation (FDI) criteria. Clinical evaluation was performed by two clinicians regarding mechanical, biological and aesthetic performances during maintenance appointments between September 2016 and August 2017. Intra-examiner and inter-examiner reliability were evaluated by calculating the intraclass correlation coefficient and inter-examiner calibration. The results were analysed by Kaplan-Meier survival estimation method and log-rank test at a 95% confidence level. Results: One hundred and sixty-three veneers were placed in 26 patients with mean clinical service of 68.1 ± 0.66 months. Overall survival rate of the veneer restoration was 97.5% with 2.5% (4 veneers) presenting clinically unacceptable problems such as fracture and debonding. The aesthetic parameter was rated as excellent by 99.4% (n = 162). Caries was not detected in any teeth. Radiographic examination determined the development of a periapical lesion in one patient after veneer placement. Most patients were comfortable with the restoration and satisfied with the aesthetic results. Conclusion: Ceramic veneers demonstrated a high survival rate with most failure cases resulting from fracture and debonding.
DOI: 10.14457/cu.the.2017.174
title: EFFECT OF REMINERALIZATION ON COLOR CHANGE OF BLEACHED TOOTH

description: The aim of this in vitro study was to investigate the effect of remineralization and time on the color and microhardness change of teeth bleached using 10% carbamide peroxide (10%CP) or 40% hydrogen peroxide (40%HP). Seventy-two 6x6x2 mm3 enamel slabs were prepared from human premolars. The specimens’ color and Vickers’ microhardness were recorded at baseline (T0). The specimens were divided into six groups, two groups were treated with 10%CP with or without casein phosphopeptides and amorphous calcium phosphate (CPP-ACP) (10%CP and 10% CP/CPP-ACP, respectively), two groups were treated with 40% HP with or without CPP-ACP (40%HP and 40%HP/CPP-ACP, respectively), one group received no bleaching (CON) and another group received only CPP- ACP treatment without bleaching, (CON/CPP-ACP). The CPP-ACP groups were treated with CPP-ACP twice daily for 5 minutes for seven days after completing their respective protocol. The color change and Vickers’ microhardness were recorded at three time points after treatment; 1 day (T1), 2 weeks (T2), and 1 month (T3). After 1 month, tooth color changed (∆E) in all groups at every time point, however, significant ∆E was found only at T3 for the 10% CP and the CON/CPP-ACP groups (p&lt;0.05). Microhardness tended to decrease from the baseline (T0) value at each time point. There were significant differences between time points in microhardness (∆VHN) in the 40%HP, CON, and CON/CPP-ACP groups. A relationship between ∆E and ∆VHN was found in the 10%CP and 10%CP/CPP-ACP groups. In summary, bleached teeth whiteness decreased in the 10%CP group from T1 to T3. The CPP-ACP can prevent color relapse in 10%CP/CPP-ACP and CON/CPP-ACP groups. Microhardness improved in the 10%CP/CPP-ACP group compared with 10%CP group at T3. Both tooth whiteness and microhardness were stable for at least one month when CPP-ACP was used as an intervention in 10% CP/CPP-ACP group.
DOI: 10.14457/cu.the.2017.175
title: A COMPARISON OF TAPER-IMPLANT DESIGNS AND BONE QUALITY ON THE PRIMARY STABILITY: AN IN VITRO BIOMECHANICAL STUDY

description: Objective To investigate the effect of the taper-implant design and the effect of bone quality on the primary stability in terms of insertion torque test, removal torque test and resonance frequency analysis. Methods Five taper-implant designs were test in artificial bone blocks with four qualities. Five repetitions per implant design were placed in each bone quality started from softest bone block. The implant motor was used to prepared the osteotomy sites and implant insertion according to manufacturers' recommendation. Peak insertion torque values were measured and recorded by implant motor when the platform of the implant flush to the bone level. Resonance frequency analysis was measure by Osstell ISQ device. The implant stability quotients were recorded. Finally, the implants were unscrewed by implant motor and the peak removal torque values were recorded. Same implants were reused with the same protocol in the rest of the test, from softer to harder test blocks respectively. The data of insertion torque values, implant stability quotients and removal torque values were statistically analysed by two-way factorial ANOVA to investigate the interaction effect of two independent variables (implant design and bone quality), (p=0.05). Results In insertion torque and removal torque tests, the interaction effects of implant design and bone quality were statistically significant. However, the interaction effect was not found in resonance frequency analysis group. Conclusion Within the limitations of this study, it can be concluded that selecting the proper design of tapered implant regarding to the quality of surgical bone site can achieve predictable primary stability outcome in terms of insertion torque and removal torque.
DOI: 10.14457/cu.the.2017.176
title: Effect of 3-methacryloxypropyltrimethoxysilane modified zinc oxide nanoparticles incorporated in polymethylmethacrylate material on antifungal, optical and mechanical properties

description: This study aimed to evaluate 1) the characteristics of different amount of 3-methacryloxypropyltrimethoxysilane (MPS) deposited on zinc oxide nanoparticles (ZnOnps) by Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) before and after tetrahydrofuran washing, 2) the effect of different MPS amount deposited on ZnOnps incorporated in PMMA material on mechanical properties, and 3) the effect of different ZnOnps amounts with or without MPS incorporated in PMMA material on antifungal, optical and mechanical properties. The FTIR and TGA results showed the success of silanization. The monolayered silane molecules were parallelly oriented on the ZnOnps surface. The different MPS amounts (0-14.4 wt%) deposited on ZnOnps incorporated in PMMA material demonstrated no significant differences on mechanical properties. The different amount (1.25, 2.5 and 5 wt%) of non-silanized (Nosi) or silanized (Si) ZnOnps incorporated in PMMA material on antifungal, optical and mechanical properties were evaluated by direct contact test, optical test and three-point bending test. With the same ZnOnps amount, the Si groups demonstrated a greater reduction in C. albicans compared with the Nosi groups. The color difference and opacity of the Nosi groups were greater when comparing with the Si groups. The flexural strength of Si groups, except for the 1.25% groups, was significantly greater compared with the Nosi groups. It was concluded that PMMA material incorporated with silanized ZnOnps, particularly 2.5% of silanized ZnOnps, had a greater antifungal effect, less color changes and opacity compared with non-silanized ZnOnps, while retaining its mechanical properties.
DOI: 10.14457/cu.the.2017.177
title: Immunohistochemical assessment of the peri-implant soft tissues around different abutment materials : an experimental study in human

description: Objective To evaluate the effect of 4 different types of abutment material, which are titanium, zirconium oxide, gold alloy, and zirconia-coping cemented on titanium-base, on the surrounding soft tissues. Material and Methods Twenty dental implants in posterior edentulous area were randomly divided into 4 groups and inserted 4 types of abutment materials; Titanium, zirconia, gold-alloy, and titanium-base, on the implant installation surgery day. Eight weeks after implant surgery, peri-implant soft tissues around experimental abutments were harvested and split according to implant side; buccal, lingual, mesial, and distal. The specimens were processed through immunohistochemical preparation and stained with CD3, CD20, CD68, CD138, and factorVIII to identify T-cells, B-cells, macrophages, plasma cells, and microvessels, respectively. The quantitative assessment of cell markers was performed by one pathologist. The total counts of positive cell for one compartment were expressed as numbers of positive cells per square millimetre of soft tissues. The outcome was assessed immunohistochemical characteristic and microvessel density (MVD). Results Sixteen healthy patients, 6 males and 10 females, were included in this study. Total positive cells for titanium, zirconia, gold-alloy, and titanium-base, were 119.28, 177.06, 445.18, and 109, respectively. Factorial analysis of variance (factorial ANOVA) was used to analyse the data. Gold alloy group showed statistical significance higher number of positive cells, compared to titanium (p-value=0.009) and zirconia (p-value=0.042). Implant side exhibited no influence on positive cell number (p-value=0.825). Microvessel density was found no statistical difference between groups. Factorial AVOVA was performed and reported that no main effect was found in both abutment material (p-value=0.501) and implant side (p-value=0.910) to have influence on microvessel density. Conclusions Different types of abutment material had an influence on peri-implant soft tissues in immunohistochemical features. Gold alloy abutments exhibited more inflammatory cells in surrounding tissues than titanium and zirconia abutments. Different sides of implant showed no statistical difference in peri-implant tissues response in immunohistochemical aspect and microvessel density. The tissues around gold alloy abutment tended to experience a higher rate of inflammation-associated processes when compared to titanium and zirconia abutments.
DOI: 10.14457/cu.the.2017.178
title: The application of prostacyclin in promoting angiogenesis of dental pulp tissue in a three dimensional organ culture system

description: Background: Dental pulp vitality can be threatened by carious or iatrogenic exposure that can lead to pulp tissue loss. The formation of a vascular network is crucial to provide a suitable environment for tissue regeneration. Thus, promoting angiogenesis is essential for successful pulpal repair in regenerative endodontics therapy. Iloprost, a prostacyclin analog, promotes vascularization in several organs such as, heart, lung, and corneal. Previously, it has been demonstrated that, iloprost induced pulpal blood flow and enhanced dentin formation in a rat mechanical pulp exposure model. However, the angiogenic effect of iloprost on the human dental pulp vasculature remains unknown. Objective: The present study investigated the effect of iloprost on promoting dental pulp angiogenesis using the tooth-slice organ culture system. Materials and methods: Tooth-slices with intact dental pulp tissues were prepared from extracted human third molars. Dental pulp tissue viability was analyzed by live/dead cell confocal microscopy. The tooth-slices were cultured without iloprost (control group) or with iloprost at a dose of 10-6 M. The microvessel density and vascular endothelial growth factor (VEGF) expression in the cultured tooth-slices were determined by immunohistochemical staining. The collagen deposition was determined by Masson’s Trichrome and immunofluorescent staining. A PKA-inhibitor was used to identify the molecular mechanisms regulated by the cAMP-dependent protein kinase A (PKA) that govern iloprost in promoting angiogenesis. Results: The dental pulp tissue architecture in the human tooth-slices model were maintained and remained viable when cultured in serum-free media. Iloprost increased the microvessel density as shown by a higher number of von Willibrand Factor-positive blood vessels when compare with the control tooth slice. A significant increased in the VEGF expression and the collange 1 (COL1) production were also observed in the tooth-slices cultured with iloprost. The effect of iloprost on angiogenesis and collagen synthesis were abolished following inhibition of protein kinase A activity. Conclusion: Human tooth-slices provide a valuable and easy-to-obtain model to investigate the effect of bioactive molecules used in dental pulp regeneration. This study, for the first time, showed that tooth slices could be kept viable under serum-free conditions for up to 3 days. Iloprost promoted angiogenesis, increased new vessel formation, and induced collagen deposition. This study proposes the clinical value of iloprost as a drug for inducing angiogenesis that can increase the success of pulp regeneration.
DOI: 10.14457/cu.the.2017.179
title: THE RELATIONSHIP BETWEEN INCOME AND FOOD INTAKE IN CHINA

description: This study investigated the effect of food intake, which is considered a form of health investment, on income in China, accounting also for socioeconomic factors. It used the 2011 wave of the China Health and Nutrition survey, including 42,870 observations in the analysis. Six dependent variables, each representing a different measure of income, were explored. The main explanatory variables included a 3-day total food consumption (grams), a 3-day average intake of energy (kilocalories), a 3-day average intake of carbohydrate (grams), a 3-day average intake of protein (grams) and a 3-day average intake of fat (grams). Personal, household, and area characteristics were also controlled for. Multivariate linear regression ordinary least squares models were used and the Box-Cox tests showed that the more appropriate functional form for the dependent variables were the log as opposed to the linear form. Results showed that food intake, taken as an investment for health, had a statistically significant impact on income. In particular, the 3-day average protein intake seemed to have the strongest effect; it was persistently positive and statistically significant across all measures of income. This was consistent with an extended version of the human capital theory, where good health improves income. A positive and statistically significant relationship was also found between income and the following variables: education and professional types of occupation.