Premaxilla
Premaxilla | |
---|---|
median nasal prominence | |
Identifiers | |
TA98 | A02.1.12.031 |
TA2 | 833 |
FMA | 77231 |
Anatomical terminology] |
The premaxilla (or praemaxilla) is one of a pair of small
Human anatomy
Incisive bone | |
---|---|
Details | |
Identifiers | |
Latin | os incisivum |
TA98 | A02.1.12.031 |
TA2 | 833 |
FMA | 77231 |
Anatomical terms of bone |
In
It is formed from the fusion of a pair of small
Incisive bone and premaxilla
Incisive bone is a term used for mammals, and it has been generally thought to be
Embryology
In the embryo, the nasal region develops from
The first ossification centers in the area of the future premaxilla appear during the seventh week above the germ of the second incisor on the outer surface of the nasal capsule. After eleven weeks an accessory ossification center develops into the alar region of the premaxilla. Then a premaxillary process grow upwards to fuse with the frontal process of the maxilla; and later expands posteriorly to fuse with the alveolar process of the maxilla. The boundary between the premaxilla and the maxilla remains discernible after birth and a suture is often observable up to five years of age. [1]
It is also common in non-mammals, such as chickens, that premaxilla is derived from
In bilateral
Evolutionary variation
Forming the oral edge of the upper jaw in most
Reptiles and most non-mammalian
However, embryonic and fossil studies in 2021 suggest that the incisive bone, which has been called "premaxilla" in therian mammals, has been largely replaced by septomaxilla; and that only a palatal part of the incisive bone remains a vestige of premaxilla.[4] If this theory is accurate, the bones that have been called "premaxilla" in therian mammals are not entirely homologous to the original premaxilla of other vertebrates.
The differences in the size and composition in the premaxilla of various families of bats is used for classification.[10]
The premaxillae of squamates are fused; this feature can be used to distinguish fossil squamates from relatives.[11]
History
In 1573, Volcher Coiter was the first to illustrate the incisive suture in humans. Pierre Marie Auguste Broussonet and Félix Vicq-d'Azyr were the first to describe the incisive bone as a separate bone within the skull in 1779 and 1780, respectively.[2]
In the 1790s,
References
- ^ ISBN 978-3-13-799101-4.
- ^ S2CID 13069026.
- ^ Gaupp, E. (1905). "Neue Deutungen auf dem Gebiete der Lehre vom Säugetierschädel". Anat. Anz. 27: 273–310.
- ^ PMID 34716275.
- ^ "Nasal Anatomy". Medscape. June 2011. Retrieved 3 December 2011.
- ^ Vergervik, Karin (1983). "Growth Characteristics of the Premaxilla and Orthodontic Treatment Principles in Bilateral Cleft Lip and Palate" (PDF). Cleft Palate Journal. 20 (4). Retrieved 3 December 2011.
- ^ "Premaxilla". ZipCodeZoo. Archived from the original on 21 January 2012. Retrieved 3 December 2011.
- PMID 19419990.
- .
- ^ Myers, P.; Espinosa, R.; Parr, C. S.; Jones, T.; Hammond, G. S.; Dewey, T. A. (2006). "Premaxillae of bats". Animal Diversity Web. Archived from the original on 3 January 2012. Retrieved 3 December 2011.
- PMC 9708687.
- ISBN 0-691-02350-6.