Unique damage?related, gap?filling tooth replacement in pycnodont fishes
نویسندگان
چکیده
Most jawed vertebrates (gnathostomes) replace their teeth throughout life (polyphyodonty) and there is currently great interest in its molecular cellular basis, particularly fish. While much has still to be elucidated, it appears that whichever tooth replacement mechanism used, only one replaces predecessor, at any time. Here we present fossil crushing dentitions of two extinct pycnodont fishes, Pycnodus zeaformis maliensis. Their surface features x-ray micro-CT virtual sections show no evidence one-for-one replacement. Instead, individual large were replaced by multiple small teeth, for which, as far could ascertain, known mechanism. This occurred where underlying dentigerous bone was damaged. Small also developed parts had broken off, gaps between created the geometry close alignment rows. We compared those functionally analogous three modern fishes. Contrasting greatly pycnodonts, each showed an orderly, replacement, typical osteichthyans. propose specimens exhibit a gap-filling addition hitherto unseen gnathostomes, oral epithelium retained initiatory competence life, with programming ‘if gap exists, fill it’. would have facilitated rows, space provided ontogenetic growth. hypothesize registered absence pressure surface, initiating development, cichlid Astatoreochromis alluaudi.
منابع مشابه
Immediate total tooth replacement.
Successful implant placement at the time of extraction has been documented. Implant placement at the time of extraction was initially performed as a two-stage procedure often with barrier membranes and sophisticated second-stage surgical uncoverings. The authors describe the next generation of this technique, including atraumatic tooth removal with simultaneous root form, implant placement, and...
متن کاملImmediate Replacement of Periodontally Compromised Teeth Using Natural Tooth Pontic
This article reports a case who was treated with immediate replacement of periodontally compromised mandibular incisors using the extracted incisors as a natural tooth pontic. Following extraction and root resection of the mandibular incisors, radicular pulp was cleaned and filled with composite resin and then bonded to adjacent teeth with fiber reinforced composite resin. This is a simple, eco...
متن کاملFixed Options for Tooth Replacement
oday, numerous types of fixed prostheses are available to replace missing teeth. Developments in the field of implantology and adhesive dentistry have increased the options available for the partially edentulous patient but have also made treatment planning more complex. However, it still remains important to identify a positive ‘need’ to restore a space and to undertake a cost-benefit analysis...
متن کاملFixed Options for Tooth Replacement
oday, numerous types of fixed prostheses are available to replace missing teeth. Developments in the field of implantology and adhesive dentistry have increased the options available for the partially edentulous patient but have also made treatment planning more complex. However, it still remains important to identify a positive ‘need’ to restore a space and to undertake a cost-benefit analysis...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Palaeontology
سال: 2021
ISSN: ['0031-0239', '1475-4983']
DOI: https://doi.org/10.1111/pala.12539