Molar crown morphology varies among primates from relatively simple in some taxa to more complex in others, with such variability having both functional and taxonomic significance. In addition to the primary cusps, crown surface complexity derives from the presence of crests, cuspules, and crenulations. Developmentally, this complexity results from the deposition of an enamel cap over a basement membrane (the morphology of which is preserved as the enamel-dentine junction, or EDJ, in fully formed teeth). However, the relative contribution of the enamel cap and the EDJ to molar crown complexity is poorly characterized. In this study we examine the complexity of the EDJ and enamel surface of a broad sample of primate (including fossil hominin) lower molars through the application of micro-computed tomography and dental topographic analysis. Surface complexity of the EDJ and outer enamel surface (OES) is quantified by first mapping, and then summing, the total number of discrete surface orientation patches. We investigate the relative contribution of the EDJ and enamel cap to crown complexity by assessing the correlation in patch counts between the EDJ and OES within taxa and within individual teeth. We identify three patterns of EDJ/OES complexity which demonstrate that both crown patterning early in development and the subsequent deposition of the enamel cap contribute to overall crown complexity in primates.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/ajpa.21248 | DOI Listing |
Intensive Crit Care Nurs
January 2025
Faculty of Medicine and Health, The University of Sydney Susan Wakil School of Nursing and Midwifery Camperdown NSW Australia; Western Sydney Local Health District, North Parramatta, NSW 2141, Australia. Electronic address:
Background: Emergency departments have high levels of uncertainty, long wait times, resource shortages, overcrowding and a constantly changing environment. Patient experience and patient safety are directly linked, yet levels of patient experience are stagnant. To improve emergency nursing care and patient experience, an emergency nursing framework HIRAID® (History including Infection risk, Red flags, Assessment, Interventions, Diagnostics, communication, and reassessment) was implemented in 29 Australian emergency departments.
View Article and Find Full Text PDFJ Funct Biomater
January 2025
Dental Research Division, Guarulhos University, Guarulhos 07023-070, SP, Brazil.
This study evaluated the microbial growth profile of subgingival multispecies biofilm on 3D-printable resin-based composites (PRBCs). A 96-well cell plate cultivated a 39-species biofilm associated with periodontitis over 7 days. Cylindrical specimens with 12 mm high and 3 mm diameters were prepared by the PRBC group (Cosmos Temp-Yller; Prizma 3D Bio Crown; Prizma 3D Bio Prov) and an acrylic resin as control.
View Article and Find Full Text PDFZhonghua Kou Qiang Yi Xue Za Zhi
January 2025
Department of Oral and Maxillofacial Surgery, Shanxi Medical University School and Hospital of Stomatology, Taiyuan 030001, China.
Exploring the application of minimally invasive techniques in the extraction of impacted mandibular third molar (IMTM), to achieve the treatment goal of "less trauma, short time, fast recovery", remains the focus of dentists. For now, the IMTM are mostly extracted in pieces after removing the crown and root resistance by bone removal and tooth segmentation, using 45°reverse-angle high speed turbine, piezosurgery, chisel or other dynamic system. However, There is a lack of principle-level parsing in different provinces and primary hospitals, while experience is still the main factor in avoiding excessive bone removal in complex IMTM extraction, as well as optimizing the specific position and angle of the parting teeth, finding the fulcrum and designing the best dislocation path when there is root resistance.
View Article and Find Full Text PDFCarbohydr Polym
March 2025
Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, QC H3A 0B8, Canada; Quebec Centre for Advanced Materials (QCAM) and Pulp and Paper Research Centre, McGill University, 3420 University Street, Montreal, QC H3A 2A7, Canada. Electronic address:
The synergy between nanomaterials as solid supports and supramolecular concepts has resulted in nanomaterials with hierarchical structure and enhanced functionality. Herein, we developed and investigated innovative supramolecular functionalities arising from the synergy between organic moieties and the preexisting nanoscale soft material backbones. Based on these complex molecular nano-architectures, a new nanorod carbohydrate polymer carrier was designed with bifunctional hairy nanocellulose (BHNC) to reveal dual-responsive advanced drug delivery (ADD).
View Article and Find Full Text PDFClin Case Rep
January 2025
Student Research Committee, School of Dentistry, Mashhad University of Medical Sciences Mashhad Iran.
Radix entomolaris (RE) characterized by an extra root in mandibular molars is a rare phenotype. When this condition coincides with complex root canal curvatures or S-shaped canals, root canal therapy (RCT) challenges arise. The present study presents three cases of RE along with complex root curvatures.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!