Incidence and contributing factors of non-root canal treated teeth with chronic fatigue root fracture: A cross-sectional study.

BACKGROUND/PURPOSE: Chronic fatigue root fracture describes a root fracture in a non-root canal treated (non-RCT) tooth. This study aimed to report the incidence and contributing factors of non-RCT teeth with chronic fatigue root fracture in a Taiwanese population. METHODS: This cross-sectional study included teeth extracted at Taipei Veterans General Hospital in Taiwan between 2018 and 2019. The reasons for extractions were recorded and included vertical and horizontal root fractures (VRF and HRF). Comparisons of clinical factors between teeth with fatigue VRF and teeth with fatigue HRF were performed by chi-square or Fisher exact test, where appropriate. RESULTS: Of the 4207 extracted teeth examined, 263 (6.25%) had tooth fracture. Thirty-two non-RCT teeth had chronic fatigue root fracture, including 16 with VRF and 16 with HRF. The incidence was 0.76% (32/4207). The occurrence of chronic fatigue root fracture was higher in males (83.9%). The mean age of the 31 patients with chronic fatigue root fracture was 71.7 ± 13.1 years. More than half of these teeth had intact crowns with severe attrition. The fatigue VRF occurred more frequently in molars (P = 0.003), in roots with a long oval cross-section (P = 0.037), and in terminal teeth (P = 0.013) than the fatigue HRF. CONCLUSION: The incidence of chronic fatigue root fracture is 0.76%. Both VRF and HRF occur mainly in aged males, in posterior teeth with attrition, and in teeth without restoration. Tooth position, cross-section root morphology, and terminal tooth are contributing factors related to chronic fatigue root fracture.

Adjustable bioadhesive control of PEGylated hyperbranch brushes on polystyrene microplate interface for the improved sensitivity of human blood typing.

A PEGylated 96-well polystyrene (PS) microplate was first introduced for applications in high-throughput screening for selective blood typing to minimize the risks in blood transfusions. Herein, we present a hemocompatible PS 96-well microplate with adjustable PEGylated hyperbranch brush coverage prepared by ozone pretreated activation and thermally induced surface PEGylation. The grafting properties, hydration capacity, and blood compatibility of the PEGylated hyperbrush immobilized PS surfaces in human blood were illustrated by the combined chemical and physical properties of the surface, and the dependence of the specific absorption of human plasma fibrinogen onto the PEGylated surfaces on the grafting density was analyzed by monoclonal antibodies. The surface coverage of PEGylated brushes plays a major role in the bioadhesive properties of modified PS microplates, which in turn control the level of agglutination sensitivity in blood typing. The bioadhesive resistance toward proteins, platelets, and erythrocytes in human whole blood showed a correlation to the controlled hydration properties of the PEGylated hyperbrush-modified surfaces. Therefore, we suggested that the surface coverage of PEGylated hyperbrushes on PS surfaces can increase the sensitivity of cross-matching blood agglutination by up to 16-fold compared to that of the conventional 96-well virgin PS due to the regulated biorecognition of hematocrit and antibodies of the PEGylated hyperbrush-modified surfaces.

A NMR-based metabolomic approach for differentiation of hagfish dental and somatic skeletal muscles.

The hagfish dental muscle is a large and specialized element of the feeding apparatus that helps ingest food. This muscle has enzymatic activities and contractile properties different from the hagfish somatic skeletal muscle. To verify the functional relevance of protein alterations, we examined the metabolomic differentiation of hagfish dental and somatic skeletal muscles using ¹H-nuclear magnetic resonance (NMR)-based metabolomics and multivariate analysis that separated hagfish dental and somatic muscles by principal component analysis and partial least squares for discriminant analysis. Our analysis of assigned metabolites showed that anserine and taurine levels were higher in dental muscle, but creatine, fructose, glucose, glycerate, pyruvate, and succinate levels were higher in somatic muscle. We concluded that the primary energy sources of dental and somatic muscles are related to the citric acid cycle and the anaerobic glycolysis and metabolism of creatine. Thus, ¹H-NMR-based metabolomics can be integrated with the previous proteomic approach to derive biochemical and physiological information about hagfish muscles.