Search PubMedSearch

SEARCH · Search PubMed

Results for “Crowns”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

4 recordsLinked to original sources

Marginal fit and five-year outcomes of posterior monolithic zirconia restorations: A randomized paired and observational clinical study.

OBJECTIVES: The aim of this study was to evaluate the marginal fit and five-year clinical performance of posterior 5 mol% yttria-partially stabilized zirconia restorations. A randomized paired comparison with lithium disilicate crowns was performed for marginal fit. METHODS: A total of 65 posterior restorations were placed in 38 patients, including 32 zirconia crowns, 17 lithium disilicate crowns, and 16 zirconia partial coverage restorations. In the randomized paired comparison, 17 patients received one lithium disilicate crown and one zirconia crown. Additional zirconia crowns (n=15) and zirconia partial coverage restorations (n=16) were included in a prospective observational cohort. The primary outcome was marginal fit within the randomized cohort. Marginal and internal fit were assessed using the replica technique. Marginal and internal gap values were compared using the Wilcoxon signed-rank test; clinical outcomes were analyzed descriptively, and Kaplan-Meier estimates were calculated for survival and complication-free survival. Clinical performance was assessed using CDA criteria, periodontal parameters, complication recording, and patient-reported outcomes. Clinical examinations were performed at baseline and at 12, 24, 36, 48, and 60 months. RESULTS: Mean marginal gap values at the crown margin were 46 ±33 µm for lithium disilicate crowns and 50 ±32 µm for zirconia crowns (p>0.05). No restoration required replacement, resulting in 100% restoration survival after a median follow-up of 60 months (range: 57-64 months). Most complications were biological or functional, including endodontic, periodontal, occlusal, and proximal-contact-related events. One zirconia partial coverage restoration exhibited a small ceramic fracture managed by polishing. The Kaplan-Meier probability of complication-free survival was 76.4% for zirconia crowns, 66.7% for lithium disilicate crowns, and 87.5% for zirconia partial coverage restorations. CONCLUSIONS: In the randomized paired comparison, 5 mol% yttria-partially stabilized zirconia crowns showed marginal gap values similar to lithium disilicate crowns. All restorations remained in situ during the observation period. Lower complication-free survival was mainly related to biological and functional events and should be interpreted separately from restoration survival. CLINICAL SIGNIFICANCE: Clinical evidence for posterior 5 mol% yttria-partially stabilized zirconia restorations remains limited. This study provides mid-term clinical data on crowns and partial coverage restorations. In the randomized full-crown comparison, marginal fit was similar to that of lithium disilicate crowns, supporting the clinical consideration of monolithic zirconia restorations for posterior teeth.

Humans

An RPA-assisted homogeneous electrochemical DNA sensor for on-site eDNA detection toward early warning of crown-of-thorns starfish outbreaks.

Crown-of-thorns starfish (COTS) outbreaks seriously threaten coral reef ecosystems, while conventional monitoring approaches are time-consuming and often lack sufficient sensitivity for early warning. Existing electrochemical DNA sensors usually require complex electrode-surface immobilization procedures, which can lead to uneven probe distribution, significant steric hindrance, and poor stability. Meanwhile, the low concentration of environmental DNA (eDNA) in marine environments further complicates detection. To overcome these challenges, this study developed a homogeneous electrochemical DNA sensor assisted by recombinase polymerase amplification (RPA) for COTS eDNA detection. Target DNA was first amplified by RPA, and the amplification products were then hybridized in solution with capture probe (CP)-modified magnetic beads (MB) and biotin-labeled signal probe (SP) to form sandwich-structured MB complexes. These complexes were subsequently magnetically enriched and immobilized on the electrode surface for electrochemical signal readout. Under optimized conditions, the sensor displayed a linear response to COTS genomic DNA from 3.77 fg/μL to 1 ng/μL, with an LOD of 2.02 fg/μL and an LOQ of 3.77 fg/μL. The sensor was applied to Xisha Islands samples, and the results agreed with droplet digital PCR (ddPCR) (P > 0.05), demonstrating its potential for sensitive and reliable on-site COTS eDNA detection.

Animals

Clinical outcomes of zirconia dental restorations: A systematic review and meta-analysis.

OBJECTIVES: To evaluate the survival and success rates of zirconia dental restorations (ZDRs) and their complications. DATA & SOURCES: Electronic searches of PubMed, Cochrane, Embase and Web of Science were conducted up to January 1, 2026. Clinical studies with at least 1-year follow-up evaluating zirconia dental restorations in natural teeth were included. Survival rates, success rates, and biological and mechanical complications were analyzed. Risk of bias was assessed using RoB 2, Newcastle-Ottawa Scale (NOS), and Joanna Briggs Institute tools (JBI). Certainty of evidence was evaluated using the GRADE approach. STUDY SELECTION & RESULTS: Sixty-six studies published between 2008 and 2025 were included. Pooled survival rates ranged from 92.9% to 98.7% up to 10 years for single crowns (SCs), 77.6% over 10 to 13 years for fixed dental prostheses (FPDs), 97.4% for resin-bonded FPDs (RBFPDs) over 10 to 15 years, from 50.0% to 52.6% over 9 to 13 years for conventional cantilever FPDs (CFPDs) and 89.0% for inlay-retained FPDs (IRFPDs) over 10 years. Pooled success rates were 46.1% for SCs over 10 years, 40.1% for FDPs over 10 to 13 years, 84.3% for RBDPDs over 10 to 15 years, 12.5% to 22.6% for CFPDs over 9 to 13 years and 70.3% for IRFPDs over 10 years. Biological and mechanical complication rates were 12.1% and 53.9% for SCs at 10 years, 19.4% and 46.7% for FPDs over 10 to 13 years, 50.0% and 37.5% for CFPDs at 9 years, 21.4% and 14.3% for IRFPDs at 3 years, and 3.3% and 8.0% for RBFPDs over 10 to 15 years. Restorations treated with airborne-particle abrasion (APA) combined with 10-methacryloyloxydecyl dihydrogen phosphate (MDP) achieved favorable short-term clinical outcomes, with pooled survival and success rates of 98.6% and 97.7% for SCs, and 98.1% and 70.1% for IRFPDs, respectively. The included studies were assessed as having low to moderate risk of bias using RoB 2, NOS, and JBI tools, but GRADE assessment yielded evidence of very low certainty. CONCLUSIONS: ZDRs generally demonstrated acceptable to excellent short- to long-term survival and success outcomes. Mid- to long-term clinical performance was varied according to restoration types. The RBFPDs had relatively low complication rates, followed by the SCs, the FPDs and the IRFPDs. CFPDs exhibited relatively low success rates and high complication rates. The predominant biological complications were secondary caries and pulpitis or apical periodontitis, while chipping and debonding were the most common mechanical complications. APA treatment followed by application of MDP is capable of producing favorable short-term clinical outcomes. CLINICAL SIGNIFICANCE: ZDRs except for CFPDs could achieve favorable mid- to long-term clinical performance. CFPDs should be conducted with caution.

Zirconium

Uce-based phylogeny and classification of Megachilini.

The generic-level classification of the bee tribe Megachilini (Megachilidae) has remained controversial due to poor phylogenetic resolution at the base of the group, particularly among the brood parasitic genera and the numerous dauber ("Chalicodoma s. l.") lineages. We present a phylogenomic analysis of Megachilini based on ultraconserved elements (UCEs), sampling 52 ingroup taxa with emphasis on the dauber lineages. We also present a combined UCE + six-gene analysis to improve taxon coverage, resulting in a dataset with 127 ingroup taxa. Maximum likelihood, coalescent, and Bayesian analyses of multiple UCE matrices recover largely congruent topologies with substantially improved support relative to previous studies. Our results strongly support the monophyly of Megachilini, the early divergence of Noteriades and Gronoceras, and a single origin of brood parasitism. All remaining non-parasitic Megachilini form a moderately supported clade sister to the brood parasitic lineage. The leafcutter bees are monophyletic and nested within dauber lineages. Several major dauber clades are consistently recovered, including an exclusively Australian clade corresponding to the Hackeriapis group of subgenera, while several recognized subgenera are paraphyletic. The lineage known as Morphella, previously placed in synonymy with the subgenus Callomegachile, was not closely related to that subgenus and is here treated as a valid subgenus. Divergence-time analyses place the crown age of Megachilini in the late Eocene to early Oligocene, with major extant lineages diversifying during the Miocene. Limited morphological diagnosability of several clades indicates that splitting non-parasitic lineages into numerous genera would result in an impractical classification that would widen the gap between taxonomists and non-specialists and exacerbate the taxonomic impediment in bees. We therefore advocate retaining a single genus Megachile for non-parasitic Megachilini (excluding Noteriades and Gronoceras), as the classification best supported by phylogenomic evidence and most robust to future taxon sampling.

Animals