Analysis of Thrombin-Activated Platelet-Derived Exosome (T-aPDE) Potential for Dental Pulp Regeneration: In-Vitro Study.

OBJECTIVE: This study analyzed the potential of various concentrations of the thrombin-activated platelet-derived exosome (T-aPDE) to regenerate the dental pulp by performing an in-vitro analysis of the cell viability, migration activity, and vascular endothelial growth factor A (VEGF-A) expression of human dental pulp stem cells (hDPSCs). MATERIAL AND METHODS: The hDPSCs were collected from nine third molar teeth of nine healthy donors and were isolated and cultured using the explant method. They were harvested between the third and fourth passages and starved, after which they were seeded in the following treatments: Dulbecco's Modified Eagle Medium and 10% platelet-rich plasma-thrombin as the control groups, and 0.5, 1, and 5% T-aPDE as the experimental groups. All groups had three biological triplicates (Triplo) and two number of experiments. The T-aPDE was analyzed using transmission electron microscopy testing, particle size analyzer, and CD63 + and CD81 + specific immune phenotyping flow cytometry tests for plasma exosomes. The cell viability was evaluated using the colorimetric assay of activity cellular enzymes (MTT assay); the migration activity, using scratch assay; and the VEGF-A expression, using enzyme-linked immunosorbent assay. RESULTS: The highest viability absorbance value of hDPSCs after 24, 48, 72 hours of observation was in the 5% T-aPDE group (p<0.05). Whereas, the closest distance result of migratory activation hDPSCs was also in the same group (p<0.05). However the highest VEGF-A expression of hDSPCs was noted in the same group at 72 hours observation (p<0.05). STATISTICAL ANALYSIS: The data were analyzed using one-way analysis of variance and the Kruskal-Wallis test. The statistical power was set at p <0.05 CONCLUSION: The 5% T-aPDE had a higher potential to induce dental pulp regeneration than the other groups.

Characterization, Physical Properties, and Biocompatibility of Novel Tricalcium Silicate-Chitosan Endodontic Sealer.

OBJECTIVE: The purpose of this study was to compare the characteristics, physical properties, and biocompatibility of the novel tricalcium silicate-chitosan (TCS-C) sealer with AH Plus and Sure-Seal Root. MATERIALS AND METHODS: The TCS-C powder was prepared by mixing tricalcium silicate with 2% water-soluble chitosan at a 5:1 ratio, followed by sufficient addition of 10 g/mL ratio of double-distilled water to form a homogeneous cement. Material characterizations (the Fourier Transform InfraRed [FTIR] and X-ray diffraction [XRD]), physical property investigations (flow and film thickness), and cytotoxicity tests in 3T3 mouse embryo fibroblast cell (MTT assay method) were performed on sealers, and the results were compared with those of the commercial products. STATISTICAL ANALYSIS: Statistical analysis was performed on flow and film thickness. The normality of the data was tested using the Shapiro-Wilk test. Statistical analysis was performed with one-way analysis of variance (ANOVA). The level of significance was set at p < 0.05. RESULTS: The TCS-C showed a mean flow of 31.98 ± 0.68 mm, compared with Sure Seal Root at 26.38 ± 0.69 mm and AH Plus at 26.50 ± 0.12 mm. The TCS-C showed a mean film thickness of 60 ± 10.0 mm compared with Sure-Seal Root at 50 ± 10.0 mm and AH Plus at 40 ± 15.8 mm. The TCS-C exhibited low to no cytotoxicity in fibroblast cell at all concentrations and exposure times. CONCLUSION: Adding water-soluble chitosan may improve the physical and biologic properties of tricalcium silicate cement. The novel TCS-C sealer did not fully meet the physical properties of an endodontic sealer, but it was not cytotoxic to fibroblast cells.

Efficacy of Rice Husk Nanosilica as A Caries Treatment (Dentin Hydroxyapatite and Antimicrobial Analysis).

OBJECTIVE: Rice husk nanosilica has a porous, amorphous structure with a silica (SiO2) surface. Silica interacts with calcium ions to form hydroxyapatite and can induce the formation of reactive oxygen species (ROS), which harm microorganisms. This research determines the effect of rice husk nanosilica on the increase in dentin hydroxyapatite and its antimicrobial effects against Streptococcus mutans. MATERIALS AND METHODS: We divided 27 dental cavity samples into three groups (n = 9). Group 1: normal dentin, Group 2: demineralized dentin, Group 3: demineralized dentin treated with rice husk nanosilica. The samples were analyzed using X-ray diffraction (XRD) to evaluate the formation of dentin hydroxyapatite. To analyze the viability of S. mutans after exposure to 2% nanosilica rice husk, we conducted an antimicrobial MTT assay. STATISTICAL ANALYSIS: The Kruskal-Wallis test evaluates the formation of dentin hydroxyapatite, and the t-test evaluates the viability of S. mutans. RESULTS: There was an increase in the amount of dentin hydroxyapatite after the application of rice husk nanosilica compared with the control group (normal dentin), and 2% rice husk nanosilica had an antimicrobial effect (p < 0.005) in the group exposed to it. CONCLUSION: Rice husk nanosilica can induce the formation of dentin hydroxyapatite and has antimicrobial effects.

Characterization of Novel Cement-Based Carboxymethyl Chitosan/Amorphous Calcium Phosphate.

OBJECTIVE: This study aimed to analyze, evaluate, and characterize novel cement-based carboxymethyl chitosan/amorphous calcium phosphate (CMC/ACP). MATERIALS AND METHODS: The three cement groups studied were gypsum (Gyp), and CMC/ACP-gypsum cement-based 5% (5% CAG) and 10% (10% CAG). The groups were characterized using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), setting time, and scanning electron microscopy (SEM) data. The characterization results were analyzed qualitatively, but the data for setting time were analyzed using SPSS (p < 0.05). STATISTICAL ANALYSIS: Data were statistically analyzed. One-way analysis of variance was used to compare numerical (parametric) data between more than two separate groups followed by post hoc Tukey. RESULTS: FTIR showed phosphate groups indicate the presence of calcium phosphate in the form of amorphous (ACP) in the CMC/ACP, CMC/ACP post-milled powder, and CMC/ACP cement-based (5% CAG and 10% CAG). XRD showed no difference in the diffraction spectra among the Gyp, 5% CAG, and 10% CAG groups. SEM images revealed that the CMC/ACP cement-based groups (5% CAG and 10% CAG) showed CMC/ACP cluster filled with hollow spaces between the gypsum crystals and aggregations surrounding the gypsum crystals. The CMC/ACP showed envelopes and attached to the crystalline structures of the gypsum. Setting times of 5% CAG and 10% CAG showed significant differences compared with Gyp (p < 0.05). CONCLUSION: The result of our study showed that CMC/ACP cement-based (5% CAG and 10% CAG) demonstrated amorphous characteristic, which can stabilize calcium ions and phosphate group (ACP). In addition, the modification of gypsum using CMC/ACP as cement-based extended the time of setting.

The Effect of Calcium Gluconate on Platelet Rich Plasma Activation for VEGF-A Expression of Human Dental Pulp Stem Cells.

OBJECTIVE: Platelet-rich plasma (PRP) activation is an important factor in triggering the initial release of blood-derived growth factors from platelets. Vascular endothelial growth factor-A (VEGF-A) can be expressed by human dental pulp stem cells (hDPSCs) and plays an important role in dental pulp angiogenesis. The aim of this study is to analyze the effects of calcium gluconate on PRP activation in hDPSC VEGF-A expression. MATERIALS AND METHODS: Two types of PRP and their corresponding activators were analyzed in this study: PRP (activated using calcium chloride/CaCl2) and PRP-T (activated using CaCl2 with the addition of 10% calcium gluconate). hDPSCs were obtained by using an out-growth method (DPSCs-OG), and harvest between the fifth and sixth passages, then cultured in three different media groups: control, PRP, and PRP-T, which were planted in 96 wells (5 × 103 each well). The VEGF-A expression of hDPSCs was analyzed by using an ELISA test and observed at 24, 48, and 72 hours. STATISTICAL ANALYSIS: This study was performed by using one-way ANOVA (p < 0.05) test. RESULTS: There were significant differences between all groups (p < 0.05) at 48 and 72 hours of observations, and no significant differences in the PRP and PRP-T groups at 48 and 72 hours of observations (p > 0.05). CONCLUSION: PRP and PRP-T were equally effective in inducing VEGF-A expression of hDPSCs.

The effect of rice husk nanosilica hydroxyl compound on dentin biomineralization.

Rice husk nanosilica contains hydroxyl for dentin remineralization. The aim of this study was to analyze and correlate the ability of rice husk nanosilica to induce hydroxyapatite dentin. The detachment of hydroxyl from rice husk nanosilica was analyzed using the sol-gel and pyrolysis methods with Fourier transform infrared spectroscopy. Subsequently, exposing of the demineralized dentin to rice husk nanosilica was performed for a comparison. The formation of hydroxyapatite on dentin was analyzed using X-ray diffraction. The amount of hydroxyl released from the two methods was then correlated with the hydroxyapatite that formed at the dentin. The extraction of hydroxyl on rice husk nanosilica with two methods was the same. Analysis of the amount of hydroxyapatite dentin with both the methods corresponds to each other. The correlation test obtains the value of R = 0.656. Rice husk nanosilica has a similar capability to release hydroxyl compound and form hydroxyapatite dentin using two methods. The creation of hydroxyapatite dentin is not only caused by the exposure of rice husk nanosilica but also owing to other factors that might reinforce the process of hydroxyapatite formation.

Broken File Retrieval in the Lower Right First Molar Using an Ultrasonic Instrument and Endodontic Micro Forceps.

Broken files affect cleaning, shaping, and filling processes of the root canal, thereby causing maintenance failure. Objective. This report explains how to remove broken files using ultrasonic instruments and endodontic micro forceps. Case Report. A 25-year-old female patient had incomplete root canal treatment at the lower right first molar 1 week ago. There were radiolucency in the bifurcation and apical root and the presence of broken files in the 1/3 coronal mesiolingual root. The retrieval started by making a staging platform with an ET20 ultrasonic tip. Endodontic micro forceps were used including a screw wedge that works by clamping the file fragments through a mechanical lock and pulling them to the coronal. Conclusion. It is possible to successfully remove broken files from the root canal using ultrasonic instruments and endodontic micro forceps.

The Ability of Biodentine™ of Guided Tissue Remineralization (GTR): Analysis Using SEM, EDX and TEM

Objective: To analyze the Biodentine™ capability in guided tissue remineralization. Material and Methods: Four premolar with two cavities per tooth of 3 mm depth were demineralized with EDTA 17% in shaking incubator at 37°C temperature. After 7 days, the sample were washed with aquabidest then were soaked in 20 ml NaCl 1 M (pH 7.0) at 25°C temperature for 8 hours. The samples were divided into two groups: G1: The control group (cavity directly restored with composite resin); G2: Biodentine™ group (cavity with Biodentine™ as a base then restored with composite resin). All samples were stored in shaking incubator under PBS solution at 37°C temperature. SEM, EDX and TEM analysis were performed on the 7th and 14th day. Results: The 14th day Biodentine group had the best SEM remineralization feature with irregular dentine tubular features covered by density of mass. In the EDX analysis, the concentration of calcium ion of the Biodentine group was higher than the control group on the 7th day analysis (Biodentin™ 10.2167 and control 1.9667) and on the 14th day analysis (Biodentine™ 29.833 and Control 22.080). The Biodentine™ group and control group of the 7th and 14th day experienced significant increases in calcium ion concentration while the concentration of phosphate ion in the Biodentine™ and control group had a much lower value of calcium either on the 7th or 14th day. The TEM analysis of Biodentine™ group showed more intrafibrillar remineralization than the control group. The feature of intrafibrillar dentin remineralization is analyzed by looking at the density of black dots in collagen. Conclusion: Biodentine™ is able to trigger the process of remineralization by guided tissue remineralization.

Ideal Concentration of Advanced-Platelet Rich Fibrin (A-PRF) Conditioned Media for Human Dental Pulp Stem Cells Differentiation

Abstract Objective: To discover the ideal concentration of Advanced Platelet Rich Fibrin (A-PRF) as modification of PRF, for human Dental Pulp Stem Cells (hDPSCs) differentiation. Material and Methods: hDPSCs were devided into five experimental groups: Group I (control group) consist of hDPSCs cultured in 10% FBS, Group II consist of hDPSCs cultured in 1% A-PRF, Group III consist of hDPSCs cultured in 5% A-PRF, Group IV consist of hDPSCs cultured in 10% A-PRF and Group V consist of hDPSCs cultured in 25% A-APRF. All group have been observed for 7 and 14 days and each group had three biological replicates (triplo). Formation of the mineralized nodules was detected after 7 days by Alizarin red-based assay and Dentin Sialophosphoprotein (DSPP) expression after 7 and 14 days quantified by ELISA reader. Statistical analysis was proven with Kruskal-Wallis and post hoc Mann-Whitney test Results: The differentiation of hDPSCs in all A-PRF groups was significantly different on day-7 (p<0.05) compare to control group (Group I). There were no significant differences between all groups on day-14 (p>0.05). Significantly differences between Group II (1% A-PRF) and Group I (control), Group II (1% A-PRF) and Group III (5% A-PRF), also Group II (1% A-PRF) and Group V (25% A-PRF) was found from post hoc test analysis Conclusion: The ideal conditioned media concentration for differentiation of human dental pulp stem cells was on 1% up to 5% A-PRF group.

Comparison of Apical Adaptation Between Several Obturation Methods: An in Vitro Study

Objective: To compare lateral compaction obturation with carrier-based gutta-percha and downpack-backfill. Material and Methods: Ninety tooth with single root canal were prepared with rotary Protaper and divided into 3 groups: Group 1 obturated with lateral heated compaction (LHC), Group 2 with carrier-based gutta-percha (CP) and Group 3 with downpack-backfill (DB). The apical one-third adaptation was determined by examining the dye penetration between obturation material and root canal wall on the horizontal cut samples. The data received was analyzed using SPSS 17 software. Chi-square statistical test was done with level of significance (α) of 0.05. Results: The DB group had the highest amount of score of 0, followed by CP group and LHC group. The DB group had 28 samples (93.3%) with score of 0, which was the largest compared to the CP and LHC group. All groups had some score 2, and score 3 and 4 were only examined in the LHC group Adaptation of the apical one-third on DB group had the best result, followed by CP and LHC group (p>0.05). Conclusion: The adaptation of apical one-third by downpack-backfill was the best among the three groups, but there was no statistically significant difference among those groups.