<P>It is known from the paleontology studies of eutherian mammals that incisor numbers were reduced during evolution. The evolutionary lost incisors may remain as vestigial structures at embryonic stages. The recapitulation of the incisor patter...
http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
https://www.riss.kr/link?id=A107485821
2016
-
SCI,SCIE,SCOPUS
학술저널
923-930(8쪽)
0
상세조회0
다운로드다국어 초록 (Multilingual Abstract)
<P>It is known from the paleontology studies of eutherian mammals that incisor numbers were reduced during evolution. The evolutionary lost incisors may remain as vestigial structures at embryonic stages. The recapitulation of the incisor patter...
<P>It is known from the paleontology studies of eutherian mammals that incisor numbers were reduced during evolution. The evolutionary lost incisors may remain as vestigial structures at embryonic stages. The recapitulation of the incisor patterns among mammalian species will potentially uncover the mechanisms underlying the phenotypic transition of incisors during evolution. Here, we showed that a minute tooth formed in the presumptive groove region of the gerbil upper incisor at the early developmental stages, during which multiple epithelial swellings and Shh transcription domains spatiotemporally appeared in the dental epithelium, suggests the existence of vestigial dental primordia. Interestingly, when we trimmed the surrounding mesenchyme from incisor tooth germs at or before the bud stage prior to ex vivo culture, the explants developed different incisor phenotypes ranging from triplicated incisors, duplicated incisors, to Lagomorpha-like incisors, corresponding to the incisor patterns in the eutherian mammals. These results imply that the phenotypic transition of incisors during evolution, as well as the achievement of ultimate incisors in adults, arose from differential integrations of primordia. However, when the incisor tooth germ was trimmed at the cap stage, a grooved incisor developed similar to the normal condition. Furthermore, the incisor tooth germ developed a small but smooth incisor after the additional removal of the minute tooth and a lateral rudiment. These results suggest that multiple dental primordia integrated before the cap stage, with the labial primordia contributing to the labial face of the functional incisor. The minute tooth that occupied the boundary of the 2 labial primordia might be implicated in the groove formation. This study sheds light on how rudiments incorporate into functional organs and aids the understanding of incisor evolution.</P>
Tertiary Dentin Formation after Indirect Pulp Capping Using Protein CPNE7