Article
Anatomy & Morphology
Molly J. Fawcett, Stephan Lautenschlager, Jordan Bestwick, Richard J. Butler
Summary: This study used finite element analysis to compare the functional morphology of basal pseudosuchian archosaurs with the stress distribution of post-Triassic theropod dinosaurs. The results showed some degree of functional convergence, but also revealed that the basal loricatan Saurosuchus had a weaker bite force and likely consumed softer parts of carcasses. This finding highlights the functional diversity of basal pseudosuchians and the functional differences between Triassic and post-Triassic apex predators.
ANATOMICAL RECORD-ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY
(2023)
Article
Veterinary Sciences
Maria E. Littles, Sangeeta Rao, Kristin M. Bannon
Summary: This study used cone beam computed tomography to describe variations in the anatomic position of the infraorbital canal relative to the roots of the maxillary fourth premolar tooth for three different canine skull types. The findings suggest that extra caution should be taken with dolichocephalic and brachycephalic skull types to avoid iatrogenic trauma to the infraorbital canal and the orbit during surgical procedures on the maxillary fourth premolar tooth.
FRONTIERS IN VETERINARY SCIENCE
(2022)
Article
Veterinary Sciences
Han Chia, Kendall Taney, Don Hoover, James B. Robertson, Lenin A. Villamizar-Martinez
Summary: Based on retrospective evaluation of cone-beam computed tomography and high-definition computed tomography exams from 103 small breed dogs under 15 kg, the study found that most of the roots of the first mandibular molar tooth in these dogs were located at the lingual aspect of the mandibular canal (82.7%) with an overall superimposition median with the canal of 100% and 90% for the mesial and distal roots, respectively. Straddle tooth roots were not common in the dogs of this study.
FRONTIERS IN VETERINARY SCIENCE
(2021)
Article
Agriculture, Dairy & Animal Science
Bernard Turek, Kamil Gorski, Olga Drewnowska, Roma Buczkowska, Natalia Kozlowska, Rafal Sapierzynski
Summary: This article presents a case of ossifying fibroma in the nasal cavity of a 2-year-old horse, highlighting the clinical features, diagnosis, and successful management through surgical excision. The patient remained asymptomatic postoperatively, showing no signs of recurrence two years later.
Article
Biology
Giacinto De Vivo, Stephan Lautenschlager, Jakob Vinther
Summary: Radiodonts evolved into the largest nektonic predators during the Cambrian period, with different species having adaptations for feeding on prey of various sizes. The limited dexterity and inefficient feeding methods may have contributed to their eventual replacement by other marine predators.
PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2021)
Article
Dentistry, Oral Surgery & Medicine
Carlos Henrique Ferrari, Amjad Abu Hasna, Frederico Canato Martinho
Summary: This study used CBCT images to evaluate the proximity between tooth apices and surrounding structures, finding a predominance of high-risk proximity in several teeth. Differences in risk proximity were also observed between mandibular teeth and buccal cortical plates.
BRAZILIAN ORAL RESEARCH
(2021)
Article
Veterinary Sciences
Graca Silva, Pedro S. S. Babo, Jorge Azevedo, Manuela E. E. Gomes, Carlos Viegas, Joao F. Requicha
Summary: This study used mCT technology to determine the relative mineral density (MD) of feline teeth. The results showed that the mean MD of root tissues was 1.374 +/- 0.040 g·cm(-3), and the mean MD of hard root tissues was 1.402 +/- 0.035 g·cm(-3). The study suggests that the measurement of MD through mCT could be a useful method for diagnosing and characterizing dental pathology.
VETERINARY SCIENCES
(2023)
Article
Dentistry, Oral Surgery & Medicine
Afsaneh Rahmati, Elham Khoshbin, Abbas Shokri, Hadis Yalfani
Summary: This study used CBCT to evaluate the root canal morphology of primary molars. The results showed a wide variation in the number of roots and canals, with 3 canals and 3 roots being the most common in maxillary first molars. Vertucci's type IV was the most common canal type, and the buccal surface had the highest percentage of concavities. These findings emphasize the need for careful treatment of primary molars due to their complex root canal anatomy.
Article
Biochemistry & Molecular Biology
Pei Li, Binghui Zeng, Weihong Xie, Xue Xiao, Ling Lin, Dongsheng Yu, Wei Zhao
Summary: In this study, a Kdf1 missense mutation knock-in mouse model was successfully constructed using CRISPR/Cas9 gene-editing technology. The enamel structure defects in the Kdf1 mutant mice were characterized, including chalky appearance, abnormal prism structure, decreased mineral density, altered crystal ordering degree, and chemical composition changes. These findings support the potential role of the KDF1 gene in the natural development of enamel.
Article
Medicine, General & Internal
Zaki Hakami, Hussain Y. A. Marghalani, Ismaeel Hedad, Mazen Khawaji, Ghadah Abutaleb, Amjad Hakami, Salem Almoammar, Abdulrahman Alshehri
Summary: This study compared tooth color and enamel and dentinal thickness between orthodontically treated and untreated individuals. The results showed significant differences in tooth color but not in enamel and dentinal thickness between the two groups. There were weak to moderate correlations between tooth color and enamel and dentinal thickness.
Article
Multidisciplinary Sciences
Tea Maho, Joseph J. Bevitt, Robert R. Reisz
Summary: The discovery of articulated pelvic region and additional isolated material of Varanops brevirostris supports the existence of this large varanopid species at the Richards Spur locality. The presence of distinct anatomical features, such as blade-like neural spines and excavated pubis, confirms the autapomorphies previously suggested for this species. Histological analysis and neutron computed tomography indicate that the articulated specimen likely belonged to an adult individual.
Article
Dentistry, Oral Surgery & Medicine
Yijin Shi, Yanling Wang, Han Ge, Pengfei Diao, Xiaomeng Song, Hongbing Jiang, Dongmiao Wang
Summary: This retrospective study aimed to comprehensively delineate the epidemiological and 3-dimensional radiographic characteristics of non-third molar impacted teeth in a Chinese dental population. The majority of impacted teeth were located in the maxillary canines, and the most frequently associated lesion was external root resorption of the adjacent tooth.
CLINICAL ORAL INVESTIGATIONS
(2022)
Article
Multidisciplinary Sciences
Van-Khoa Pham, Tran-Lan-Khue Pham
Summary: The aim of this study was to evaluate the agreements between different methods in estimating root canal length, including cone-beam computed tomography (CBCT) at different slice thicknesses, dedicated software, or an electronic apex locator (EAL), and the actual lengths (AL). The study showed that the EAL was an accurate and reliable method for measuring root canal length.
SCIENTIFIC REPORTS
(2022)
Article
Dentistry, Oral Surgery & Medicine
Kug Jin Jeon, Chena Lee, Yoon Joo Choi, Sang-Sun Han
Summary: The study revealed that as the position of posterior teeth became more posterior, the buccolingual dimension of the roots increased, the buccal bone thickness increased, and the distance to the mandibular canal became shorter. Contact was the most common relationship between the buccal cortical bone and root in the mesial root of the first molars and first premolars.
CLINICAL ORAL INVESTIGATIONS
(2021)
Article
Dentistry, Oral Surgery & Medicine
Xiaoxia Feng, Yiru Jiang, Yafen Zhu, Lingling Hu, Jue Wang, Yezi Qi, Siyao Ma
Summary: This study compared the designed and achieved mesiodistal angulation of maxillary canines and posterior teeth during first premolar extraction with clear aligner treatment. It identified the main influencing factors for preventing unwanted tipping of teeth towards the extraction space. The results showed that the designed crown tipping of posterior teeth and mesial tipping of canines can prevent unwanted tipping towards the extraction space.
AMERICAN JOURNAL OF ORTHODONTICS AND DENTOFACIAL ORTHOPEDICS
(2022)
Article
Biology
Christopher T. Griffin, Michelle R. Stocker, Caitlin Colleary, Candice M. Stefanic, Emily J. Lessner, Mitchell Riegler, Kiersten Formoso, Krista Koeller, Sterling J. Nesbitt
Summary: Morphology plays a crucial role in vertebrate paleontology, providing the basis for taxonomic identification and evolutionary hypotheses. Assessing maturity is essential for studying ontogenetic changes, population structure, and paleoecology in saurian reptiles, but the methodological challenges and terminological ambiguity need to be addressed. Integrating data from extant and extinct taxa, as well as using multiple lines of evidence, is crucial for improving clarity and coherence in maturity assessment among saurian reptiles.
BIOLOGICAL REVIEWS
(2021)
Article
Multidisciplinary Sciences
Michelle R. Stocker, Christopher A. Brochu, E. Christopher Kirk
Summary: Dramatic early Cenozoic climatic shifts led to global faunal reorganization, with various vertebrate groups widespread in the warm, greenhouse conditions of the early Eocene but experiencing a significant drop in diversity near the Eocene-Oligocene boundary. This period also saw the introduction of more dry-tolerant taxa, as well as a loss of diversity in crocodyliforms.
Article
Anatomy & Morphology
Gabriel Mestriner, Aaron LeBlanc, Sterling J. Nesbitt, Julio C. A. Marsola, Randall B. Irmis, Atila Augusto Stock Da-Rosa, Ana Maria Ribeiro, Jorge Ferigolo, Max Langer
Summary: Histological data show that silesaurids do not have the permanent gomphosis seen in crocodylians and dinosaurs, but instead exhibit delayed ankylosis, with teeth being suspended in sockets by a periodontal ligament before eventually mineralizing and fusing to the jaws. This suggests a paedomorphic trend in tooth attachment evolution, with possible convergence in the dinosaur and crocodylian gomphosis. The relative duration of different phases of dental ontogeny needs to be carefully considered when analyzing dental characters in early archosaur phylogenies.
ANATOMICAL RECORD-ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY
(2022)
Article
Anatomy & Morphology
William G. Parker, Sterling J. Nesbitt, Randall B. Irmis, Jeffrey W. Martz, Adam D. Marsh, Matthew A. Brown, Michelle R. Stocker, Sarah Werning
Summary: A study describes the early-diverging pseudosuchian Revueltosaurus callenderi from Arizona, based on 12 skeletons found in a bonebed, which possess unique features that help clarify its relationships within Pseudosuchia. Histological analysis of the femur indicates that the individuals were not young juveniles and had slow growth rate.
ANATOMICAL RECORD-ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY
(2022)
Article
Multidisciplinary Sciences
Christopher R. Noto, Domenic C. D'Amore, Stephanie K. Drumheller, Thomas L. Adams
Summary: The poorly studied terrestrial fossil record of the mid-Cretaceous interval in North America has been enhanced by recent focus on fossil localities in the western United States. The Woodbine Group in Texas, a recently separated deposit from its western counterparts, has yielded a rich variety of vertebrate remains from the Cenomanian age. Discovery of non-avian theropod material in this deposit provides valuable insights into the faunal diversity and ecosystem dynamics during this time period.
Article
Paleontology
Sterling J. Nesbitt, Michelle R. Stocker, Martin D. Ezcurra, Nicholas C. Fraser, Andrew B. Heckert, William G. Parker, Bill Mueller, Saradee Sengupta, Saswati Bandyopadhyay, Adam C. Pritchard, Adam D. Marsh
Summary: Archosauromorph reptiles underwent rapid diversification, with increases in morphological and body size disparity, and expanded into new adaptive landscapes. Malersaurus is identified as an early diverging, but late-surviving, carnivorous member of Azendohsauridae within Allokotosauria. Fossils from western North America suggest that Allokotosauria had a near-global distribution from the Middle Triassic to Late Triassic.
PAPERS IN PALAEONTOLOGY
(2022)
Meeting Abstract
Biochemistry & Molecular Biology
Khanh To, Todd Green, Lawrence Witmer, Michelle Stocker
Article
Anatomy & Morphology
Rebecca K. Hawkins, Christopher J. Bell, Jennifer C. Olori, Michelle R. Stocker
Summary: A snake-like body plan and burrowing lifestyle are characteristic of many vertebrate groups due to convergent evolution. One such group is amphisbaenians, limbless fossorial lizards that exhibit head-first burrowing behavior. Their skulls are more rigid and coossified compared to nonburrowing lizards. In this study, intraspecific variation in the cranial osteology of amphisbaenians was investigated using seven individuals of Diplometopon zarudnyi. The study revealed qualitative and quantitative differences in skull and individual skull element morphology, which may be the result of different ontogenetic stages or biomechanical optimization for head-first burrowing.
JOURNAL OF MORPHOLOGY
(2022)
Article
Multidisciplinary Sciences
Stephanie K. Drumheller, Clint A. Boyd, Becky M. S. Barnes, Mindy L. Householder
Summary: Fast burial is a common mechanism for preserving soft tissues in fossils, but not all fossils fit into this category. This study presents an Edmontosaurus mummy that demonstrates an alternative fossilization pathway for resistant soft tissues. The well-preserved skin on the specimen shows signs of carnivore activity, indicating incomplete scavenging of the carcass. This allowed for gases, fluids, and microbes associated with decomposition to escape, enabling the durable soft tissues to persist before desiccation and fossilization.
Article
Multidisciplinary Sciences
Ben T. T. Kligman, Bryan M. M. Gee, Adam D. D. Marsh, Sterling J. J. Nesbitt, Matthew E. E. Smith, William G. G. Parker, Michelle R. R. Stocker
Summary: Scientists have discovered the oldest caecilian fossil in Arizona, USA, suggesting that the origin of caecilians can be traced back to the Triassic period. These fossils reveal the tempo and mode of early caecilian morphological and functional evolution, providing new evidence supporting a single origin of caecilians with other amphibians.
Article
Anatomy & Morphology
Adam C. C. Pritchard, Randall B. B. Irmis, Jennifer C. C. Olori, Sterling J. J. Nesbitt, Nathan D. D. Smith, Michelle R. R. Stocker, Alan H. H. Turner
Summary: The femoral morphology of Triassic drepanosauromorphs is unique, allowing for greater femoral adduction and protraction compared to other Permian-Triassic diapsids. This study provides valuable insights into the evolution of reptile femora and their locomotor capabilities.
ANATOMICAL RECORD-ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY
(2023)
Article
Multidisciplinary Sciences
Rodrigo T. Muller, Martin D. Ezcurra, Mauricio S. Garcia, Federico L. Agnolin, Michelle R. Stocker, Fernando E. Novas, Marina B. Soares, Alexander W. A. Kellner, Sterling J. Nesbitt
Summary: Studying the well-preserved partial skeleton of Venetoraptor gassenae provides a more comprehensive understanding of the skull and ecology of dinosaur and pterosaur precursors. The discovery of a sharp raptorial-like beak and long trenchant claws suggests the loss of quadrupedalism in these precursors. The morphological diversity of these precursors exceeds that of Triassic dinosaurs and resembles that of Triassic pterosaurs.
Article
Paleontology
Davide Foffa, Sterling J. J. Nesbitt, Ben T. T. Kligman, Richard J. J. Butler, Michelle R. R. Stocker
Summary: Anisodontosaurus greeri is a small-bodied tetrapod with a heterodont dentition from the Middle Triassic. Its evolutionary relationships have been uncertain, but new data from micro-computed tomography scans suggest that it belongs to the archosauromorph clade Trilophosauridae. Comparison with other trilophosaurids reveals similarities with Variodens inopinatus, and cladistic analyses confirm the existence of two distinct lineages within Trilophosauridae. These findings have important implications for our understanding of the early evolution and distribution of trilophosaurids.
JOURNAL OF VERTEBRATE PALEONTOLOGY
(2023)
Article
Paleontology
Adam D. Marsh, William G. Parker, Sterling J. Nesbitt, Ben T. Kligman, Michelle R. Stocker
Summary: Non-archosaur archosauromorphs, including a newly discovered malerisaurine azendohsaurid named Puercosuchus traverorum, were important members of the global Middle and Late Triassic continental ecosystems. This finding is significant for understanding the diversity of azendohsaurids during the middle and late Triassic periods.
JOURNAL OF PALEONTOLOGY
(2022)
Article
Paleontology
Khanh H. T. To, Sterling Nesbitt, Michelle R. Stocker
JOURNAL OF VERTEBRATE PALEONTOLOGY
(2021)