Statement Of Problem: Proper marginal, axial, and occlusal adaptation of dental restorations is essential for their long-term success. Production protocols including digital impression systems have been developed, but little information is available on the adaptation of zirconia restorations produced via them.
Purpose: The purpose of this in vitro study was to compare the effects of digital impression protocols on the marginal, axial, and occlusal adaptation of zirconia copings.
Material And Methods: Thirty extracted human maxillary premolar teeth without caries or defects were used. The teeth were prepared for zirconia crowns and randomly divided into 3 groups. Zirconia copings were designed at a thickness of 0.5 mm with 30 μm of simulated die spacer starting 1 mm from the margin of preparations. They were produced using computer-aided design-computer-aided manufacture (CAD-CAM) protocol with a conventional impression (group Cn) and 2 different production protocols with digital impressions (group C) and group Tr. The marginal, axial, and occlusal discrepancies of these copings were measured using the silicone replica technique with stereomicroscopy at ×50 magnification, and the data were analyzed with 1-way ANOVAs (α=.05).
Results: The mean marginal discrepancy values were 85.6 μm for group Cn, 58.7 μm for group C, and 47.7 μm for the Tr group. Significant differences were found among the production protocols in marginal, axial, and occlusal discrepancies (P<.05). Copings fabricated with the aid of digital impressions had significantly fewer marginal discrepancies than those of group Cn (P<.05). Group Tr exhibited the lowest marginal discrepancy, whereas groups Cn and C demonstrated similar axial adaptations (P>.05), and group Tr revealed the lowest axial discrepancy (P<.05). With regard to the occlusal discrepancy evaluation, group Tr had the lowest discrepancy. However, no significant differences was found between groups C and Cn (P>.05).
Conclusions: The copings produced with the aid of digital impression systems exhibited better marginal and occlusal adaptation than those of the copings produced with the aid of conventional impression.
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http://dx.doi.org/10.1016/j.prosdent.2016.06.004 | DOI Listing |
Inflammation
January 2025
The Key Laboratory of Spine and Spinal Cord Disease of Jiangxi Province, Nanchang, 330006, China.
Inflammatory bone resorption represents a pathological condition marked by an increase in bone loss, commonly associated with chronic inflammatory conditions such as rheumatoid arthritis and periodontitis. Current therapies primarily focus on anti-inflammatory drugs and bisphosphonates; however, these treatments are limited due to side effects, inadequate efficacy, and unpredictable long-term complications. Kurarinone (KR), a bioactive compound isolated from the traditional Chinese herb Sophora flavescens, exhibits a range of biological activities, including anti-inflammatory, anticancer, and cardiovascular protective effects.
View Article and Find Full Text PDFClin Exp Nephrol
January 2025
Reach-J Steering Committee, Tsukuba, Ibaraki, Japan.
Background: Although several studies have examined the Kidney Disease Quality of Life (KDQOL) in patients with chronic kidney disease (CKD), the factors associated with kidney-related symptoms have not been fully explored.
Methods: This nationwide multicenter cohort study enrolled 2248 patients. To identify the factors associated with each item or the three KDQOL domains, such as burden of kidney disease, symptoms/problems of kidney disease, and impact of kidney disease on daily life, multiple regression analysis was performed using baseline data.
Methods Enzymol
January 2025
Natural Products Research Center, Chengdu Institute of Biology, Chinese Academy of Science, Chengdu, P.R. China. Electronic address:
As a promising therapeutic approach, the RNA editing process can correct pathogenic mutations and is reversible and tunable, without permanently altering the genome. RNA editing mediated by human ADAR proteins offers unique advantages, including high specificity and low immunogenicity. Compared to CRISPR-based gene editing techniques, RNA editing events are temporary, which can reduce the risk of long-term unintended side effects, making off-target edits less concerning than DNA-targeting methods.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Molecular Synthesis Center, Key Laboratory of Marine Drugs of Ministry of Education, Shandong Key Laboratory of Glycoscience and Glycotherapeutics, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China.
2-Deoxy-β-glycosides are essential components of natural products and pharmaceuticals; however, the corresponding 2-deoxy-β-glycosidic bonds are challenging to chemically construct. Herein, we describe an efficient catalytic protocol for synthesizing 2-deoxy-β-glycosides via either IPrAuNTf-catalyzed activation of a unique 1,2--positioned C2--propargyl xanthate (OSPX) leaving group or (PhO)PAuNTf-catalyzed activation of a 1,2--C2--alkynylbenzoate (OABz) substituent of the corresponding thioglycosides. These activation processes trigger 1,2-alkyl/arylthio-migration glycosylation, enabling the synthesis of structurally diverse 2-deoxy-β-glycosides under mild reaction conditions.
View Article and Find Full Text PDFPLoS One
January 2025
Jindal School of Psychology and Counselling, OP Jindal Global University, Sonipat, Haryana, India.
Introduction: Teachers are pivotal in shaping educational environments and student development but face significant occupational stress and high rates of mental problems. Despite the availability of various psychosocial interventions, comprehensive evidence of their effectiveness and implementation is limited for this occupational group, especially in low- and middle-income countries (LMICs). This mixed methods study aims to conduct a scoping review of characteristics, effectiveness, and implementation outcomes of psychosocial interventions for teachers' mental health and mental problems, integrating these with teachers' lived experiences to inform the implementation of mental health interventions in LMICs.
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