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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

Abstract Identifying new biomarkers associated with central visual function impairment is important in advanced glaucoma patients. This retrospective cross-sectional study enrolled 154 eyes from 154 subjects, consisting of 86 patients with advanced open-angle glaucoma (mean deviation of 24-2 visual field [VF] tests

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

Abstract In this study, we investigated the patterns of visual field (VF) defects and the diagnostic abilities of VF tests using different strategies in Asian patients with hydroxychloroquine retinopathy. Patients screened for hydroxychloroquine retinopathy using optical coherence tomography, fundus autofluorescence, VF, and/or multifocal electroretinography were included. The VF was performed using the Humphrey 30-2 and/or 10-2 strategy, and 2,107 eyes of 1,078 patients with reliable results, including 136 eyes of 68 patients with hydroxychloroquine retinopathy, were analyzed. The characteristics of VF findings were evaluated and the sensitivity and specificity were compared between the 30-2 and 10-2 tests in subgroups of retinopathy severity and pattern. The most common VF defect pattern was partial- or full-ring scotoma in both the 10-2 and 30-2 tests. Among the eyes with hydroxychloroquine retinopathy that underwent both tests, 14.2% showed a disparity between the two tests, almost all at the early stage. In overall and early pericentral retinopathy, the sensitivity of the 30-2 test was significantly higher than that of the 10-2 test (95.7% vs. 77.1% and 90.6% vs. 53.1%, respectively; P

Abstract In this study, we investigated the clock-hour topographic characteristics and extent of photoreceptor and retinal pigment epithelium (RPE) damage and correlated the extent with functional defects in eyes with hydroxychloroquine retinopathy. A total of 146 eyes of 75 patients diagnosed with hydroxychloroquine retinopathy were included. The clock-hour topographic characteristics (relative to the fovea) and extent of the photoreceptor and RPE defects in the parafoveal and pericentral areas were evaluated by reviewing the radial-scan optical coherence tomography (OCT) and wide-field fundus autofluorescence (FAF) images. The extent of outer retinal damage in the parafoveal and pericentral areas were correlated with the perimetric parameters of the Humphrey 10–2 and 30–2 tests, respectively. Although the photoreceptor damage was most commonly noted at the temporal to inferior locations in both parafoveal and pericentral areas, the RPE damage in the pericentral eyes was most commonly noted in the nasal area and showed topographic discrepancies with photoreceptor damage. The extent of RPE damage was almost identical between OCT and FAF images, whereas photoreceptor defect extent was significantly greater on OCT images. The extent of parafoveal and pericentral photoreceptor damage on OCT images was significantly correlated with perimetric parameters of the 10–2 and 30–2 tests, respectively (all P

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.

Elevated intraocular pressure (IOP) in glaucoma causes retinal ganglion cell (RGC) loss and damage to the optic nerve. Although IOP is controlled pharmacologically, no treatment is available to restore retinal and optic nerve function. In this paper, we aimed to develop a novel gene therapy for glaucoma using an AAV2-based thioredoxin 2 (Trx2)-exoenzyme C3 transferase (C3) fusion protein expression vector (scAAV2-Trx2-C3). We evaluated the therapeutic effects of this vector in vitro and in vivo using dexamethasone (DEX)-induced glaucoma models. We found that scAAV2-Trx2-C3-treated HeLa cells had significantly reduced GTP-bound active RhoA and increased phosphor-cofilin Ser3 protein expression levels. scAAV2-Trx2-C3 was also shown to inhibit oxidative stress, fibronectin expression, and alpha-SMA expression in DEX-treated HeLa cells. NeuN immunostaining and TUNEL assay in mouse retinal tissues was performed to evaluate its neuroprotective effect upon RGCs, whereas changes in mouse IOP were monitored via rebound tonometer. The present study showed that scAAV2-Trx2-C3 can protect RGCs from degeneration and reduce IOP in a DEX-induced mouse model of glaucoma, while immunohistochemistry revealed that the expression of fibronectin and alpha-SMA was decreased after the transduction of scAAV2-Trx2-C3 in murine eye tissues. Our results suggest that AAV2-Trx2-C3 modulates the outflow resistance of the trabecular meshwork, protects retinal and other ocular tissues from oxidative damage, and may lead to the development of a gene therapeutic for glaucoma.

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.

The rate of preterm birth is increasing worldwide and preterm infants are susceptible to oral health problems. Hence, this study aimed to investigate the effect of premature birth on dietary and oral characteristics as well as dental treatment experiences of preterm infants using a nationwide cohort study. Data was retrospectively analyzed from National Health Screening Program for Infants and Children (NHSIC) of the National Health Insurance Service of Korea. 5% sample of children born between 2008 and 2012 who completed first or second infant health screening were included and divided into full-term and preterm-birth groups. Clinical data variables such as dietary habits, oral characteristics, and dental treatment experiences were investigated and comparatively analyzed. Preterm infants showed significantly lower rates of breastfeeding at 4–6 months (p

Background/purpose: Due to the unique properties of healing processes and cellular differentiation, the gingiva and dental pulp have attracted attention as a potential source of mesenchymal stem cells (MSCs). The purpose of this study was to obtain molecular-level information on these tissues in terms of their function and differentiation processes and investigate stemness. Materials and methods: Healthy gingival tissues were collected from patients (n = 9; aged 7–12 years) who underwent simple surgical procedures, and normal dental pulp tissues were obtained from patients (n = 25; aged 11–25 years) undergoing tooth extraction for orthodontic reasons. Complementary DNA microarray, qRT-qPCR, and immunohistochemical staining were performed to assess general and MSC gene expression patterns. Results: In the gingival tissue, genes related to keratinization, the formation of epithelial cells and ectoderm, and immune and/or inflammatory responses were highly expressed. Meanwhile, in the dental pulp tissue, genes related to ion transport, neuronal development and axon guidance, bone and enamel mineralization, extracellular matrix organization, and angiogenesis were highly expressed. When focusing on the expression of MSC genes, induced pluripotent stem (iPS) cell genes, such as Sox2, c-Myc, and KLF4, were expressed at higher levels in the gingival tissue, whereas dental stem cell genes, such as NT5E and VCAM1, were expressed in dental pulp tissue. Conclusion: We found different general and MSC gene expression patterns between the gingival and dental pulp tissue. These results have implications for future regenerative medicine, considering the application of gingival tissue as a potential source of iPS cells.

Abstract Background In patients with hepatitis C virus (HCV) and malignant lymphoma, hepatitis C flare during R-CHOP can result in discontinuation of treatment. However, appropriate therapeutic strategies for managing hepatitis C flare during R-CHOP have not been established, and this issue is complicated by conflicting results regarding the use of direct-acting antivirals in patients with uncontrolled malignancies. Case presentation We report the first case of effective and safe treatment with on-demand 8-week glecaprevir and pibrentasvir for hepatitis C flare during R-CHOP in a patient with diffuse large B-cell lymphoma (DLBCL). The patient completed five additional courses of R-CHOP without hepatic toxicity. A complete response of DLBCL and a sustained virological response were observed at 24 weeks after glecaprevir and pibrentasvir completion. Conclusion On-demand, direct-acting antivirals could be a novel strategy for managing hepatitis C flare during R-CHOP.