{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T10:15:14Z","timestamp":1789726514427,"version":"4.0.1"},"reference-count":20,"publisher":"SAGE Publications","issue":"9","license":[{"start":{"date-parts":[[1998,9,1]],"date-time":"1998-09-01T00:00:00Z","timestamp":904608000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J Dent Res"],"published-print":{"date-parts":[[1998,9]]},"abstract":"<jats:p>The temporal and spatial patterns in which teeth are initiated in the growing jaws of embryos are constant for a species but different for different species. The sources of the patterns have been explained in two ways. First, they are the outcome of reactions between molecules created at stationary targets and those which diffuse through embryonic tissues (e.g., Edmund, 1960). Second, Osborn (1978) supposed that the patterns mirror the way a (mixed) population of parent cells, the tooth clone, grows. Westergaard and Ferguson (1986, 1987, 1990) concluded, from their observations of the sequence of tooth initiation in alligators, that the complicated sequences in which 20 teeth are initiated in each tooth quadrant could not be explained by jaw growth. The present study attempts to refute this criticism by means of measurements made from the raw data published by Westergaard and Ferguson. These data reveal that new teeth, here called primary teeth, are added at a constant rate at the back of the jaw. Interstitial growth of the cells between primary teeth creates space for secondary teeth in secondary regions. The secondary regions increase in length exponentially with time. The sequence in which teeth are initiated in the growing secondary regions was found to be the same in every part of the upper and lower jaws. It was accurately reproduced by a computer program based on a linear contraction rate of inhibitory zones and exponential growth of secondary regions. The results suggest that the posterior progress zone in alligator embryos grows about 125 \u03bcm a day. Newly initiated tooth germs are surrounded by an inhibitory zone about 250 \u03bcm in diameter. These zones contract from 20 to 30 \u03bcm a day until they are about 170 \u03bcm in diameter. The sequences in which tooth positions are initiated in embryos may be more the result of the pattern in which cells escape from molecules that inhibit induction rather than the pattern in which cells create molecules that initiate induction.<\/jats:p>","DOI":"10.1177\/00220345980770090901","type":"journal-article","created":{"date-parts":[[2009,1,8]],"date-time":"2009-01-08T19:39:42Z","timestamp":1231443582000},"page":"1730-1738","source":"Crossref","is-referenced-by-count":21,"title":["Relationship between Growth and the Pattern of Tooth Initiation in Alligator Embryos"],"prefix":"10.1177","volume":"77","author":[{"given":"J.W.","family":"Osborn","sequence":"first","affiliation":[{"name":"Department of Oral Health Sciences, Faculty of Medicine and Oral Health Sciences, University of Alberta, Edmonton, Alberta, Canada T6G 2N8"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[1998,9,1]]},"reference":[{"key":"atypb1","first-page":"452","volume":"47","author":"DeMar RE","year":"1973","journal-title":"J Paleontol"},{"key":"atypb2","first-page":"1","volume":"52","author":"Edmund AG","year":"1960","journal-title":"Contr Life Sci Div R Ont Mus"},{"key":"atypb3","first-page":"1","volume":"56","author":"Edmund AG","year":"1969","journal-title":"Contr Life Sci Div R Ont Mus"},{"key":"atypb4","doi-asserted-by":"publisher","DOI":"10.1002\/jmor.1052180208"},{"key":"atypb5","doi-asserted-by":"publisher","DOI":"10.1007\/978-1-349-02554-1"},{"key":"atypb6","doi-asserted-by":"publisher","DOI":"10.1016\/S0092-8674(00)80333-5"},{"key":"atypb7","doi-asserted-by":"publisher","DOI":"10.1038\/225343a0"},{"key":"atypb8","first-page":"377","volume":"134","author":"Osborn JW","year":"1971","journal-title":"Proc R Soc London B"},{"key":"atypb9","first-page":"548","volume":"61","author":"Osborn JW","year":"1973","journal-title":"Am Scient"},{"key":"atypb10","doi-asserted-by":"publisher","DOI":"10.1016\/0022-5193(74)90012-5"},{"key":"atypb11","unstructured":"Osborn JW (1978). Morphogenetic gradients: fields versus clones . In: Development, function and evolution of teeth. Butler PM, Joysey KA, editors. New York: Academic Press, pp. 171-201."},{"key":"atypb12","first-page":"549","volume":"52","author":"Osborn JW","year":"1984","journal-title":"Symp Zool Soc Lond"},{"key":"atypb13","doi-asserted-by":"publisher","DOI":"10.1006\/jtbi.1993.1199"},{"key":"atypb14","doi-asserted-by":"publisher","DOI":"10.1177\/00220345880670020401"},{"key":"atypb15","doi-asserted-by":"publisher","DOI":"10.1006\/jtbi.1993.1211"},{"key":"atypb16","doi-asserted-by":"publisher","DOI":"10.1098\/rstb.1952.0012"},{"key":"atypb17","doi-asserted-by":"publisher","DOI":"10.1111\/j.1469-7998.1986.tb03657.x"},{"key":"atypb18","doi-asserted-by":"publisher","DOI":"10.1111\/j.1469-7998.1987.tb05984.x"},{"key":"atypb19","doi-asserted-by":"publisher","DOI":"10.1002\/aja.1001870407"},{"key":"atypb20","doi-asserted-by":"publisher","DOI":"10.1016\/S0022-5193(69)80016-0"}],"container-title":["Journal of Dental Research"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/00220345980770090901","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/00220345980770090901","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T21:00:56Z","timestamp":1777496456000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1177\/00220345980770090901"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1998,9]]},"references-count":20,"journal-issue":{"issue":"9","published-print":{"date-parts":[[1998,9]]}},"alternative-id":["10.1177\/00220345980770090901"],"URL":"https:\/\/doi.org\/10.1177\/00220345980770090901","relation":{},"ISSN":["0022-0345","1544-0591"],"issn-type":[{"value":"0022-0345","type":"print"},{"value":"1544-0591","type":"electronic"}],"subject":[],"published":{"date-parts":[[1998,9]]}}}