Development of Palate &
Tongue
Dr. Saleem Shaikh
Introduction
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The formation of palate and tongue is a complex and
interrelated process.
The formation of lip takes place by the fusion of maxillary
process with the frontonasal process
The maxillary process also extends backwards on either side
of the stomatodeum
From each maxillary process a plate like shelf extends
mesially. This is called as palatal process.
At this stage, there are three components which make up the
palate ◦ Frontonasal process – primitive palate (premaxilla)
◦ The two palatal shelves
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The two palatal shelves initially grow downwards (vertically)
and after sometime, these two processes swing upwards to
become horizontal.
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The process first fuses with the frontonasal process, then the
two processes fuse with each other to form the roof of the oral
cavity and separate the nasal cavity from the oral cavity.
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The fusion starts anteriorly and progresses posteriorly.
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The medial edges of the palate also fuse with the free lower
edge of the nasal septum, this separates the nasal cavity into
two parts.
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Once the fusion of the palatal shelves is complete, the anterior
part undergoes ossification to form the hard palate.
The part of the palate which is derived from the frontonasal
process forms the premaxilla, which carries the incisors.
Defective fusion of the various components of the palate gives
rise to various forms of cleft palate
Development of Tongue
Development of Tongue
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The tongue is one of the most important organ in the oral
cavity.
The tongue develops in relation to the pharyngeal arches in
the floor of the mouth.
The pharyngeal arches arises as a mesodermal thikenings in
the lateral wall of the foregut and it grows to meet the
corresponding arch on the other side.
The medial most part of the mandibular arch proliferate to
form two lingual swellings, on either side of the midline
A median swelling also appears between the two lingual
swellings – this is known as “ Tuberculum Impar”
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Another midline swellings are seen in relation to the midline
of the second third and fourth arches. This swelling is known
as the “ Hypobranchial eminence”
This eminence divides into two parts –
◦ Cranial - second and third
◦ Caudal – fourth
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◦ The anterior two third of the tongue is formed by fusion of
the
 Two lingual swellings and tuberculum impar. The
tuberculum impar regresses as the development
proceeds and most part of the developed anterior
tongue is made up of the two lingual swellings
The posterior one third of the tongue is derived from the
cranial part of the hypobranchial eminence. (the third arch
mesoderm grows over the second arch )
The posterior most part of the tongue is formed by the caudal
part of the hypobranchial eminence.
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Nerve supply of the anterior two third of the tongue –
◦ Lingual branch of the mandibular nerve – sensory
◦ Chorda tympany branch of facial nerve – taste
Posterior one third of the tongue is supplied by the
glossopharyngeal nerve
Posterior most part of the tongue is supplied by Superior
laryngeal nerve.
The muscles of the tongue are supplied by the hypoglossal
nerve.