Tooth socket histology in the Cretaceous snake<i>Dinilysia</i>, with a review of amniote dental attachment tissues

Budney, Lisa A.; Caldwell, Michael W.; Albino, Adriana M.

doi:10.1671/0272-4634(2006)26[138:tshitc]2.0.co;2

Cited by 42 publications

(80 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This tissue lacks cell spaces and produces a distinct extinction pattern under crossed-polarized light, and in strong contrast to the adjacent globular zone and more external layers (Figure 5D–5F). Topologically and histologically, this tissue is identifiable as acellular cementum, as in mammals, crocodilians, and marine reptiles [2], [3], [8], [11], [17]. In diadectids the acellular cementum coats the root orthodentine and even extends into the cores of some of the larger dentine lamellae (Figure 5C, 5D).…”

Section: Resultsmentioning

confidence: 99%

“…This tissue is clearly distinguished from the remodeled bone of the jaw by a reversal line (Figures 4F, 6F), and primary osteons and simple vascular canals are present throughout in all of the diadectid specimens that we examined. The matrix consists of woven-fiber bone, a rapidly deposited bone matrix that is characterized by random orientations of the collagen fiber matrix [3]. In longitudinal section, the bases and walls of some of the alveoli are formed by previous generations of this woven-fiber bone, and are separated from more recent generations by reversal lines (Figure 6D, 6F).…”

Section: Resultsmentioning

confidence: 99%

“…The geometry of the attachment site of the tooth to the jaw has been used in phylogenetic reconstructions of lissamphibians [1], snakes and other squamates [2], [3] and mammals [4]. In general, three types of implantation are recognized: acrodonty (a tooth is attached to the apex of the jaw), pleurodonty (a tooth is attached to the lingual surface of the jaw), and thecodonty (a tooth is set into a deep socket in the jaw).…”

Section: Introductionmentioning

confidence: 99%

“…More recent paleontological [2], [7], [8], [17]–[20] and developmental [16], [21]–[23] studies of amniotes have suggested that cementum, alveolar bone, and the periodontal ligament are present in some capacity even in non-mammalian and non-crocodilian amniotes (Figure 2A). Much of this recent work in dental histology, however, has been limited to studies of mammals, squamates [3], [7], extant crocodilians [11], [21], and ichthyosaurs [8], [24], and has not addressed the issue of homology of these tissues at the level of Amniota.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Periodontal Ligament, Cementum, and Alveolar Bone in the Oldest Herbivorous Tetrapods, and Their Evolutionary Significance

2013

View full text Add to dashboard Cite

Tooth implantation provides important phylogenetic and functional information about the dentitions of amniotes. Traditionally, only mammals and crocodilians have been considered truly thecodont, because their tooth roots are coated in layers of cementum for anchorage of the periodontal ligament, which is in turn attached to the bone lining the alveolus, the alveolar bone. The histological properties and developmental origins of these three periodontal tissues have been studied extensively in mammals and crocodilians, but the identities of the periodontal tissues in other amniotes remain poorly studied. Early work on dental histology of basal amniotes concluded that most possess a simplified tooth attachment in which the tooth root is ankylosed to a pedestal composed of “bone of attachment”, which is in turn fused to the jaw. More recent studies have concluded that stereotypically thecodont tissues are also present in non-mammalian, non-crocodilian amniotes, but these studies were limited to crown groups or secondarily aquatic reptiles. As the sister group to Amniota, and the first tetrapods to exhibit dental occlusion, diadectids are the ideal candidates for studies of dental evolution among terrestrial vertebrates because they can be used to test hypotheses of development and homology in deep time. Our study of Permo-Carboniferous diadectid tetrapod teeth and dental tissues reveal the presence of two types of cementum, periodontal ligament, and alveolar bone, and therefore the earliest record of true thecodonty in a tetrapod. These discoveries in a stem amniote allow us to hypothesize that the ability to produce the tissues that characterize thecodonty in mammals and crocodilians is very ancient and plesiomorphic for Amniota. Consequently, all other forms of tooth implantation in crown amniotes are derived arrangements of one or more of these periodontal tissues and not simply ankylosis of teeth to the jaw by plesiomorphically retaining “bone of attachment”, as previously suggested.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Periodontal Ligament, Cementum, and Alveolar Bone in the Oldest Herbivorous Tetrapods, and Their Evolutionary Significance

2013

View full text Add to dashboard Cite

show abstract

“…Moreover, the independent evolution of the periodontal ligament in a range of non-mammalian vertebrates (see Fig. 5), notably trigger fish (Soule, 1969), extinct mosasauroid lizards (Caldwell, 2007;Luan et al, 2009), at least one fossil snake (Budney et al, 2006), crocodiles (e.g., Tadokoro et al, 1998;McIntosh et al, 2002), and many extinct archosaurs including some dinosaurs and early birds (e.g, Edmund, 1960), argues for its general utility in the coordination of feeding activity. It is even found in modern birds that have been manipulated to redevelop teeth (Cai et al, 2009).…”

Section: Discussionmentioning

confidence: 99%

Feedback control from the jaw joints during biting: An investigation of the reptile Sphenodon using multibody modelling

Curtis

Jones

Evans

et al. 2010

Journal of Biomechanics

View full text Add to dashboard Cite

Histological analysis of ankylothecodonty in Silesauridae (Archosauria: Dinosauriformes) and its implications for the evolution of dinosaur tooth attachment

Mestriner

LeBlanc

Nesbitt

et al. 2021

The Anatomical Record

View full text Add to dashboard Cite

Dinosaurs possess a form of tooth attachment wherein an unmineralized periodontal ligament suspends each tooth within a socket, similar to the condition in mammals and crocodylians. However, little information is known about tooth attachment and implantation in their close relatives, the silesaurids. We conducted a histological survey of several silesaurid taxa to determine the nature of tooth attachment in this phylogenetically and paleoecologically important group of archosaurs. Our histological data demonstrate that these early dinosauriforms do not exhibit the crocodilian/dinosaur condition of a permanent gomphosis, nor the rapid ankylosis that is plesiomorphic for amniotes. Instead, all sampled silesaurids exhibit delayed ankylosis, a condition in which teeth pass through a prolonged stage where the teeth are suspended in sockets by a periodontal ligament, followed by eventual mineralization and fusion of the tooth to the jaws. This suggests that tooth attachment in crocodylians and dinosaurs represent the further retention of an early ontogenetic stage compared to silesaurids, a paedomorphic trend that is mirrored in the evolution of synapsid tooth attachment. It also suggests that the dinosaur and crocodylian gomphosis was convergently acquired via heterochrony or, less likely, that the silesaurid condition represents a reversal to a plesiomorphic state. Moreover, if Silesauridae is nested within Ornithischia, a permanent gomphosis could be convergent between the two main dinosaur lineages, Ornithischia and Saurischia. These results demonstrate that dental characters in early archosaur phylogenies must be chosen and defined carefully, taking into account the relative duration of the different phases of dental ontogeny.

show abstract

Tooth socket histology in the Cretaceous snakeDinilysia, with a review of amniote dental attachment tissues

Cited by 42 publications

References 15 publications

Periodontal Ligament, Cementum, and Alveolar Bone in the Oldest Herbivorous Tetrapods, and Their Evolutionary Significance

Periodontal Ligament, Cementum, and Alveolar Bone in the Oldest Herbivorous Tetrapods, and Their Evolutionary Significance

Feedback control from the jaw joints during biting: An investigation of the reptile Sphenodon using multibody modelling

Histological analysis of ankylothecodonty in Silesauridae (Archosauria: Dinosauriformes) and its implications for the evolution of dinosaur tooth attachment

Contact Info

Product

Resources

About