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Background/purpose: Well-Root PT is a novel bioceramic material developed to overcome limitations of conventional calcium silicate cements. The purpose of this study was to assess the biocompatibility and bioactivity of a premixed putty-type cement, Well-Root PT. Materials and methods: Identical cylindrical samples were prepared from ProRoot MTA, Biodentine, and Well-Root PT. In vitro calcium weight volume and calcium ion release from the materials were evaluated with scanning electron microscopy and energy-dispersive spectroscopy and inductively coupled plasma-optical emission spectroscopy. An in vivo rat direct pulp capping model was implemented with the materials (n = 14 per material). The rats were sacrificed at 7 or 28 days. Hematoxylin and eosin and immunohistochemical analyses were performed. Results: In vitro calcium weight volume was 42.83 ± 8.82 % in ProRoot MTA, 47.05 ± 8.83 % in Biodentine, and 29.99 ± 4.94 % in Well-Root PT. Calcium ion releases from Well-Root PT after 7 and 28 days were similar with those from ProRoot MTA, but lower than those from Biodentine (P = 0.001 after 7 and 28 days equally). In an in vivo rat model, hematoxylin and eosin analysis showed no significant differences in inflammatory infiltration (P = 0.393) and hard tissue formation scores among the materials (P = 0.905). Also, both CD68 and DSPP expression showed similar results, with no significant differences among the materials (equally P = 0.874 for both markers). Conclusion: Within the limits of this study, Well-Root PT was comparable to ProRoot MTA and Biodentine in terms of biocompatibility and bioactivity.

Background/Aim: Tooth avulsion and delayed replantation may cause inflammatory responses and root resorption of the tooth. The aim of this study is to investigate the effect of a doxycycline-loaded nitric oxide-releasing nanomatrix (DN) gel on the delayed replantation of avulsed rat teeth, with a focus on assessing the gel’s potential to promote regeneration and inhibit complications associated with the replantation process. Materials and Methods: Twenty-four right maxillary first molars from male Sprague-Dawley rats were atraumatically extracted using sterile extraction forceps. The molars were dried for 1 h at room temperature (approximately 23 °C) and divided into four groups according to the root conditioning methods after extra-alveolar 60-min drying: Group 1, no root conditioning treatment prior to replantation; Group 2, soaking in 2% NaF solution for 5 min before replantation; Group 3, 5-min soaking in NO gel and injection of the gel into the alveolar socket; Group 4, 5-min soaking in DN gel and injection of the gel into the alveolar socket before replantation. The animals were euthanized four weeks after the operation and the specimens were evaluated histologically. Results: The use of NO gel alone showed better anti-inflammatory and periodontal effects than the control group, but it did not show a significant effect compared to the group using NaF. When using NO gel loaded with doxycycline, it showed a significant anti-inflammatory effect compared to the control group and showed a similar inhibitory effect to the group using NaF. Conclusions: Within the limits of this study, in delayed replantation situations, the control of inflammatory resorption and replacement resorption is an important factor for achieving a better prognosis of replanted teeth. Root surface treatment with DN gel decreased root resorption after delayed replantation.

Abstract Background Delphinidin (DP), an anthocyanidin found in blueberries, has antioxidant and anti-inflammatory effects. This study aimed to investigate the efficacy of DP as a storage medium for avulsed teeth. Methods Human periodontal ligament cells were cultured and exposed to DP solution (10, 50, and 100 μM), Dulbecco’s modified Eagle’s medium, Hank’s balanced salt solution and tap water. Cell counting kit-8 assays were performed after 0.5, 1, 6, and 24 h to measure the cell viability. Nitric oxide assays and gelatin zymography were performed to evaluate the anti-inflammatory effects of DP. Reverse transcription-polymerase chain reaction was used to determine the expression levels of inflammatory cytokines. Results The viability of periodontal ligament cells was greatest at 100 μM DP. At 1 h, 100 μM DP decreased nitric oxide synthesis (p

Abstract Background In clinical settings, tooth preparation for prefabricated zirconia crowns (PZCs) in the primary dentition varies widely. However, knowledge about the biomechanical behavior of PZCs in various clinical settings is limited. This study was conducted to evaluate the biomechanical behavior of PZCs in different clinical settings using 3-dimensional finite element analysis. Methods 3-dimensional models of the PZC, cement, and tooth with six different conditions were simulated in primary molar teeth, incorporating cement thickness (100, 500, and 1000 μm) and cement type (resin-modified glass ionomer cement and resin cement). A total of 200 N of occlusal force was applied to the models, both vertically and obliquely as representative cases. A general linear model univariate analysis with partial eta-squared (ηp2) was performed to evaluate the relative effects of the variables. Results The overall stress of tooth was increased as the cement space increases under oblique loading. The von Mises stress values of the resin cements were significantly higher than those of the resin-modified glass ionomer cements for all cement thicknesses (p

Background/purpose: Oral wound healing undergoes a dynamic process of oral environment. This study aimed to investigate the effects of hyaluronic acid (HA) film on oral wound healing in a rat model. Materials and methods: A total of 60 rats with tongue wounds (5 mm in diameter) were randomly divided into control (n = 20), HA gel (n = 20), and HA film groups (n = 20). The animals were sacrificed on either 3 or 7 days after the experiment. Clinical, histological, and quantitative reverse transcriptase-polymerase chain reaction analysis were performed to evaluate the healing rate, inflammation, re-epithelialization, and gene expression of wound healing biomarkers. Results: The healing rates of HA gel (84.4 ± 9.2%) and HA film (74.0 ± 15.0%) were significantly higher than that of the control (51.7 ± 16.9%) on day 7 (P

Background and Objectives: In spite of the oral environment being healing-prone, its dynamic changes may affect wound healing. The purpose of this study was to assess the oral wound healing effect of Angelica gigas Nakai (AG) prepared by hot-melt extrusion. Materials and Methods: Human gingival fibroblast (HGF) cells were treated with AG or AG via hot-melt extrusion (AGH) for 24 h to determine the optimal concentration. For evaluating the anti-inflammatory effect of AG and AGH, a nitric oxide assay was performed under lipopolysaccharide (LPS) stimulation. The wound-healing effects of AG and AGH were evaluated using cell proliferation/migration assays and wound-healing marker expression through qRT-PCR. Results: Both AG and AGH showed no cytotoxicity on HGH cells. Regarding nitric oxide production, AGH significantly decreased LPS-induced nitric oxide production (p < 0.05). AGH showed a significantly positive result in the cell proliferation/cell migration assay compared with that in AG and the control. Regarding wound healing marker expression, AGH showed significantly greater VEGF and COL1α1 expression levels than those in the others (p < 0.05), whereas α-SMA expression was significantly different among the groups. Conclusions: Within the limits of this study, AGH accelerated oral wound healing in vitro.

The characteristics of 3-dimensional (3D) cultured periodontal ligament stem cells derived from permanent teeth (pPDLSCs) and supernumerary teeth (sPDLSCs) were compared and evaluated in this study. pPDLSCs and sPDLSCs were cultured in an ultra-low attachment 6-well plate, and the changes in morphology and size were observed under an optical microscope for 14 days. Cell counting kit-8 was used to quantitatively evaluate cell viability, and a live/dead assay was performed for the qualitative assessment. The degrees of osteogenic, chondrogenic, and adipogenic differentiation of pPDLSCs and sPDLSCs were also assessed. The pPDLSCs and sPDLSCs were initially spherical, and sPDLSCs were smaller than pPDLSCs. The viability of pPDLSCs decreased by 47.9% (day 3) and 10.4% (day 7), whereas that of sPDLSCs decreased by 34.3% (day 3) and 2.5% (day 7) compared to the percentage on Day 1. No significant difference in osteogenic differentiation was found (p = 0.94); however, significant differences in adipocyte and cartilage differentiation were observed (p = 0.003 and p = 0.013, respectively). Within the limitations of this study, sPDLSCs and pPDLSCs exhibited multilineage differentiation capacities, including osteogenic, chondrogenic, and adipogenic differentiation, in 3D culture. Overall, pPDLSCs should be further investigated as a source of stem cells for tissue engineering and regenerative medicine.

Pulpectomy is a common treatment for severe carious lesions in primary molars. Care should be taken during pulpectomy of the primary teeth for successive permanent teeth. This case series report aimed to describe the cases of three patients who experienced excessive extrusion of canal filling materials and file separation during primary molar pulpectomy. The presence of separated files or excessive overfilling materials observed around successive permanent tooth germs leads to underdevelopment and may trigger cystic changes owing to abscess formation. The most important aspect is to preserve the unerupted successive developing permanent tooth. Therefore, clinicians should consider the anatomy of the primary molars prior to endodontic treatment, be careful when manipulating instruments during pulpectomy, provide appropriate treatment if iatrogenic incidents occur during endodontic treatment, and perform close follow-up to ensure the successful development and eruption of subsequent permanent teeth.

Abstract Background Internal voids of materials can serve a hub for microorganism and affect the sealing ability. This study aimed to evaluate the sealing performance of calcium silicate-based cements in immature teeth treated with regenerative endodontics. Methods Twenty single root canals from immature permanent premolars were prepared using regenerative endodontic protocols. The root canals were randomly divided into two groups and sealed with mineral trioxide aggregate (MTA) and Biodentine (BD). The teeth were kept in humid environment for 7 days and scanned using micro-computed tomography. The voids within the cements were segmented and visualized using image processing, incorporating the modified Otsu algorithm. The porosity of each sample was also calculated as the ratio between the number of voxels of voids and the volume of the cements. Tortuosity was also calculated using the A-star algorithm. Results Voids larger than 70 μm were predominantly observed in the top and interfacial surface of cements. The others were evenly distributed. MTA and BD showed the same level of porosity and tortuosity at interfacial surfaces. In inner surfaces, MTA showed more less porosity and tortuosity compared to BD (p

Abstract Background The COVID-19 pandemic changed the world and created a shift in the dental education program. This sudden change in the dental education program may have affected the academic standards of dental students. This study aimed to evaluate the overall satisfaction and effectiveness of online learning in pediatric dentistry of undergraduate dental students’ during the COVID-19 pandemic in South Korea. Methods An anonymous online survey was sent to three dental schools, and responses were collected from dental school students. Questions included the demographics, perspectives of online classes, comparison of online and offline pediatric dentistry classes and opinions on how dental schools are handling the pandemic. Students’ perspectives on online classes were evaluated based on satisfaction with online education. Data were analyzed using the Kruskal-Wallis test and the Mann-Whitney U test. Results Most students took online classes from home (80.9%) using Zoom (50.4%). The majority reported overall program satisfaction (74.1%) and agreed that universities implemented online classes well (55%). Students who were in favor of online classes responded more positively to questions on the effectiveness and safety of online learning (p

Background and Objectives: Acute kidney injury (AKI) affects the survival rate of kidney transplant organs and patients. Acute rejection (AR) due to AKI may lead to kidney transplantation failure. It is known that there is a relationship between human leukocyte antigen-G (HLA-G), which is involved in immune regulation, and AR in transplant patients. Moreover, 14-bp insertion/deletion polymorphism in the 3′ untranslated region (UTR) region of the HLA-G gene is known to affect HLA-G expression. However, its relationship to AR is still controversial. The aim of this study was to investigate whether HLA-G 14-bp insertion/deletion polymorphism contributed to the development of AR in kidney transplant patients using a meta-analysis. Materials and Methods: To perform our meta-analysis, eligible studies about HLA-G 14-bp insertion/deletion polymorphism and AR were searched in electronic databases until 1 June 2021. Finally, a total of 336 patients with AR and 952 patients without AR in relation to kidney transplantation were analyzed from a total of nine studies. Results: In our results, the Del allele and Ins/Del+Del/Del and Del/Del genotypes significantly increased susceptibility of AR in Asian populations [odds ratio (OR) = 2.359, 95% confidence interval (CI) = 1.568–3.550, p = 3.8 × 10−5; OR = 3.357, 95% CI = 1.769–6.370, p = 0.002; OR = 2.750, 95% CI = 1.354–5.587, p = 0.0052 in each model, respectively]. Conclusions: Evidence of the present results indicate that HLA-G 14-bp insertion/deletion polymorphism is associated with susceptibility to AR in the Asian population.

This study aimed to analyze the effects of pulp capping materials on gene expression changes in primary tooth-derived dental pulp cells using next-generation sequencing. Dental pulp cells were extracted and treated with mineral trioxide aggregate (MTA), Biodentine (BD), or TheraCal LC (TC). Cell viability assays were performed. Total RNA was extracted and analyzed through mRNA sequencing. Bioinformatic analysis of differential gene expression in dental pulp cells exposed to BD or TC versus MTA was performed. MTA, BD, and TC exposure had no significant effect on pulp cell viability (p > 0.05). Gene sets associated with inflammatory response (p = 2.94 × 10−5) and tumor necrosis factor alpha (TNF-α) signaling via the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway (p = 2.94 × 10−5) were enriched in all materials. In BD-treated cells, Wnt/β-catenin signaling (p = 3.15 × 10−4) gene sets were enriched, whereas enrichment of interferon gamma (IFN-γ) response (p = 3 × 10−3) was observed in TC-treated cells. In gene plot analysis, marked increases in receptor activator of nuclear factor kappa-Β ligand (RANKL) expression were seen in TC-treated cells over time. Despite the similar cell viabilities exhibited among MTA-, BD-, and TC-treated cells, patterns of gene networks differed, suggesting that diverse functional gene differences may be associated with treatment using these materials.

This study aimed to evaluate the feasibility of a 3-dimensional (3D) planned surgical guide technique designed for impacted supernumerary teeth (STs) extraction using 3D printed simulation models. In total, 17 participants from two university hospitals were recruited. Each participant performed surgery with both the conventional and surgical guide techniques. The following parameters were evaluated: (1) The time required for ST extraction, (2) the area of the window opening, and (3) the volume of the material removed. Time required for ST extraction was 213.65 ± 167.45 sec and 114.76 ± 42.87 sec in the conventional and surgical guide techniques, respectively, with significant differences (p = 0.028). The required area of the window opening was 48.10 ± 9.44 mm2 and 45.90 ± 8.17 mm2, respectively, in the conventional and surgical guide techniques, with no significant differences (p > 0.05). The required volume of the material removed was 121.65 ± 43.69 mm3 and 99.12 ± 17.88 mm3 in the conventional and surgical guide techniques, respectively, with significant differences (p = 0.031). The 3D planned surgical guide technique was effective for impacted ST extraction. Within the limits of this study, the surgical guide technique allows us to accomplish minimally invasive surgery within a shorter duration.

This report presents the therapeutic approach and results of a case of impacted undeveloped double teeth using 3D simulation in a school-age child. A 10-year-old girl was referred to hospital for the evaluation and treatment of fully impacted premolar double teeth in the left maxillary area. After evaluation, the double teeth were surgically removed, hemisected, and replanted after modification. For accurate surgery, replicas were made of the double teeth using CBCT and a 3D printer, and several mock surgeries were performed. Although remarkable signs for clinical and radiologic pathology were not found at the 5-month follow-up, short root with infraocclusion was found at the 30-month follow-up. This treatment widened the treatment spectrum with modern diagnostic approaches and preparation in large double teeth in children. [ABSTRACT FROM AUTHOR]