Unlabelled: Root canal anatomical complexities, such as isthmus, may limit the action of the endodontic instruments, irrigant solutions and intracanal medications, leading to endodontic treatment failure.
Objectives: This in vitro study assessed the type, position and incidence of isthmus in human permanent molars.
Material And Methods: One hundred and twenty eight upper and lower first and second permanent molars were analyzed. The roots were embedded in transparent resin, and then split at different distances from the apex (1.0-2.5-4.0-5.5-7.0 mm). Following the sample examination in stereomicroscope, the data were submitted to chi-square statistical test at a 5% significance level.
Results: The highest isthmus incidence was at 7.0 mm from the root apex in all samples, except the distal root of lower molars (at 5.5 mm). In upper and lower molars, type V (complete isthmus with a continuous opening between the two main root canals) was the most common classification of isthmus (28.8%). In the mesial root of first and second mandibular molars, type IV had the highest incidence (36% and 23.9%, respectively).
Conclusion: It was concluded that isthmus was widely found in flat roots, with a low percentage in areas close to the apex. In upper and lower molars, these structures were most frequently found at 7 mm from the apex.
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http://dx.doi.org/10.1590/1678-775720130585 | DOI Listing |
J Orthop Traumatol
January 2025
Unità Operativa di Ortopedia e Traumatologia, APSS Trento, Largo Medaglie d'oro, 9, 38121, Trento, Italy.
Background: The Masquelet induced membrane technique is a surgical procedure that allows the reconstruction of segmental bone defects using a relatively simple approach that requires minimal resources from both the healthcare facility and the patient. Historically applied to the lower limb, this technique is gaining increasing attention in the literature for its use in the upper limb.
Methods: A systematic review of the literature was conducted using the PubMed and Google Scholar databases to identify all studies reporting the outcomes of the Masquelet induced membrane technique in the long bones of the upper limb (humerus, radius, and ulna) with a sample size of at least 3 patients.
Adv Sci (Weinh)
January 2025
School of Integrated Circuits, Peking University, Beijing, 100871, China.
The efficient isolation and molecular analysis of circulating tumor cells (CTCs) from whole blood at single-cell level are crucial for understanding tumor metastasis and developing personalized treatments. The viability of isolated cells is the key prerequisite for the downstream molecular analysis, especially for RNA sequencing. This study develops a laser-induced forward transfer -assisted microfiltration system (LIFT-AMFS) for high-viability CTC enrichment and retrieval from whole blood.
View Article and Find Full Text PDFGlob Chang Biol
January 2025
Department of Surface Waters-Research and Management, EAWAG, Swiss Federal Institute of Aquatic Science and Technology, Kastanienbaum, Switzerland.
The primary production of fjords across the Arctic and Subarctic is undergoing significant transformations due to the climatically driven retreat of glaciers and ice sheets. However, the implications of these changes for upper trophic levels remain largely unknown. In this study, we employ both bulk and compound-specific stable isotope analyses to investigate how shifts at the base of fjord food webs impact the carbon and energy sources of consumers.
View Article and Find Full Text PDFPheochromocytoma (PHEO) currently is considered to be malignant due to metastatic potential. One of the most common familial forms of PHEO is multiple endocrine neoplasia syndrome (MEN) type 2. The penetrance of PHEO in MEN2 syndrome is up to 50% of cases.
View Article and Find Full Text PDFUnlabelled: SYNGAP1 is a key Ras-GAP protein enriched at excitatory synapses, with mutations causing intellectual disability and epilepsy in humans. Recent studies have revealed that in addition to its role as a negative regulator of G-protein signaling through its GAP enzymatic activity, SYNGAP1 plays an important structural role through its interaction with post-synaptic density proteins. Here, we reveal that intrinsic excitability deficits and seizure phenotypes in heterozygous Syngap1 knockout (KO) mice are differentially dependent on Syngap1 GAP activity.
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