The document provides information on the anatomy and development of the tongue. It discusses the tongue's embryological development from the pharyngeal arches, anatomy including muscles and vasculature, histology highlighting the different papillae and taste buds, and common clinical issues like infections and developmental disturbances. The tongue has intrinsic and extrinsic muscles that allow for various movements and plays important roles in speech, swallowing, and tasting.

1. DEPARTMENT OF PROSTHODONTICS & CROWN AND
BRIDGE
TONGUEBY
DR. KRITI TREHAN
1st MDS

2. CONTENT
• Introduction
• Development
• Anatomy
• Histology
• Clinical examination of tongue
• Developmental disturbances of tongue
• Functions
• Applied anatomy with prosthetic implications
• Conclusion
• References

3. Introduction
 The tongue is a muscular organ situated in the floor of the
mouth.
 It is associated with
functions of speech, mastication
and deglutition.
 It has an oral part that lies in the
mouth and a pharyngeal part that lies
in the pharynx.

4. Development of tongue
 Development begins
at the 4th week of the
gestation.
 The tongue develops
in relation to the
pharyngeal arches
in the floor of the
developing mouth.

7.  Development of Anterior 2/3 of the tongue
 Formed by fusion of
 2 lingual swellings
 tuberculum impar,
 Thus derieved from
first branchial arch.
 It is supplied by
lingual nerve(post-trematic)
and chorda tympani
(pre-trematic).

8. Development of Posterior 1/3
of the tongue
• From the cranial half of the
hypobranchial eminence, i.e.,
from the third arch.
• Supplied by glossopharyngeal
Nerve.
Development of posterior
most part
• From the 4th arch

10. Development of Musculature of tongue
 Derived from occipital myotomes
 Nerve supply is by hypoglossal nerve.

11. ANATOMY
 The tongue has :
 A Root
 A tip /apex
 A body which has a curved
upper surface or dorsum
and an inferior surface.

12.  The root is attached to the mandible and soft palate
above and to the hyoid bone below.
 The tip of the tongue forms the anterior free end
which, at rest, lies behind the upper incisor.
 The dorsum of the tongue is convex and divided into:
o An oral part or anterior 2/3rds
o A pharyngeal part or posterior 1/3rd

13. DORSAL SURFACE
ORAL PART
Anterior two third:
• Mucosa is rough
• Shows four types of papillae:
i. Filiform
ii. Fungiform
iii. Vallate
iv. Foliate

14. Pappilae of the tongue
 These are projections of
mucuos membrane which
gives the anterior 2/3rds of
the tongue its characteristic
roughness.

15. Vallate Papillae
 Largest among papillae
 Shape: Blunt-ended cylindrical
 Size- 1-2mm in diameter
 Number: 8 to 12
 Location: in front of sulcus
terminalis.
 Arrangement: Occur in V shape

16. Filiform pappilae
 Makes up majority of the papillae and covers the anterior
part of the tongue.
 They appear as slender, threadlike keratinized projections
 These papillae facilitate mastication (by compressing and
breaking food when tongue is apposed to the hard palate)
and movement of the food on the surface of the tongue.
 NO TASTE BUDS.

17. Fungiform pappilae
 These are mushroom shaped, more numerous near tip & margins
of tongue but some of them scattered over the dorsum.
 Smooth, round structures that appear red because of their highly
vascular connective tissue core.
 Taste buds are usually seen within the epithelium.

18. Foliate papilla
 Red leaf-like mucosal ridges
 Bilaterally at the sides of the tongue near
sulcus terminalis .
 Bear numerous taste buds

19. PHARYNGEAL PART
Posterior 1/3rd
 Lies behind the
palatoglossal arches.
 Forms the anterior wall of
the oropharynx.
 Absence of papillae.
 The mucous membrane has
many lymphoid follicles that
collectively constitute the
lingual tonsil.

20. VENTRAL SURFACE
 Covered by smooth mucous membrane
 The thin strip of tissue that runs vertically from the
floor of the mouth to the undersurface of the tongue is
called the lingual frenulum.
 It tends to limit the movement of the tongue.
 On either side of frenulum there is a prominence
produced by deep lingual veins and more laterally
there is a fold called plica fimbriata.

22. Muscles of the tongue
INTRINSIC MUSCLES
1. Superior longitudinal
2. Inferior longitudinal
3. Transverse
4. Vertical
EXTRINSIC MUSCLES
1. Genioglossus
2. Hyoglossus
3. Styloglossus
4. Palatoglossus

23. Intrinsic muscles
 Four paired
intrinsic muscles
originate and
insert within the
tongue.
 These muscles
alter the shape of
the tongue.
 It is not attached
to any bone.

24. Superior longitudinal
Origin: submucous fibrous
layer below the dorsum of the
tongue and lingual septum.
Insertion: extends to the
lingual margin
Action :
o Turns the apex and sides of the
tongue upward to make the
dorsum concave
o Shortens the tongue.
Superior
longitudinal

25. Inferior longitudinal
 Narrow band close to the inferior
surface of the tongue.
Origin: root of tongue
Insertion: apex of tongue
 Action:
o Shortens the tongue.
o Makes the dorsum convex.

26. Transverse
Origin: median fibrous
septum
Insertion: fibrous tissue at
the margins of tongue.
Action :
o Narrows and elongates the
tongue

27. Vertical
Origin: borders of the
anterior part of the
tongue.
Insertion: ventral surface
of the borders of the
tongue.
Action :
o Flattens and broadens the
tongue

28. Extrinsic muscles
 Styloglossus and Palatoglossus attach the tongue
superiorly.
 Genioglossus and Hyoglossus attach the tongue
inferiorly.

30. GENIOGLOSSUS
 Origin: Arises from superior
genial tubercle above the origin
of geniohyoid.
 Insertion :
o Upper fibres: tip of the tongue
o Middle fibres: dorsum
o Lower fibres: hyoid bone.
 Action
o Upper fibres: retract the tip
o Middle fibres: depress the tongue
o Lower fibres: protrusion of the
tongue

32. STYLOGLOSSUS
 Origin: Styloid process of
temporal bone near its apex .
 Insertion: Longitudinal part into
the inferior longitudinal muscles
Oblique part into hyoglossus
 Function: Elevates and retracts
tongue

33. HYOGLOSSUS
 Thin quadrangular muscle
 Origin: Greater horn and adjacent part of body of hyoid bone
 Insertion: Lateral surface of tongue
 Function: Depresses and retracts tongue

34. PALATOGLOSSUS
 Origin: Inferior surface of
palatine aponeurosis
 Insertion: Lateral margins
of tongue.
 Action:
o Elevates the posterior part
of the tongue.

35. Movements
Protrusion: Genioglossus on both sides acting together.
 Retraction: Styloglossus and hyoglossus on both sides
acting together.
Depression: Hyoglossus and genioglossus on both sides
acting together.
Elevation: Styloglossus and palatoglossus on both sides
acting together.

36. VASCULAR SUPPLY
 Lingual artery
 A branch of external carotid artery(after passing deep to
the hyoglossus muscles) divides into :
Dorsal lingual arteries: supply posterior part
Deep lingual artery : supplies the anterior part
Sublingual artery : supplies the sublingual gland and
floor of the mouth

38. VENOUS DRAINAGE
 Dorsal lingual vein-
drains the dorsum and
sides of the tongue.
 Deep lingual veins -
drains the tip of the
tongue and join
sublingual veins from
sublingual salivary gland
 All these veins terminate
directly or indirectly into
internal jugular veins.

39. NERVE SUPPLY

40. LYMPHATIC DRAINAGE
 Tip - Drain to submental
nodes and then directly to
deep cervical nodes.
 The right and left halves of
the anterior 2/3rds of the
tongue drain unilaterally to the
submandibular nodes.
 Posterior part - drains directly
and bilaterally to deep
cervical nodes .
 The deep cervical nodes usually
involved: jugulo-omohyoid
and jugulo-digastric nodes .

41. HISTOLOGY OF TONGUE
Mucous Membrane On Dorsal Surface
 The dorsal surface of the tongue is covered with a mucous
membrane, which is firmly adherent to the underlying
connective tissue.
The stratified squamous epithelium covering the dorsal
surface of the tongue is mostly keratinized.
 On the oral part of the dorsum it is thin, forms papillae
and is adherent to the muscles.

42. On the pharyngeal
part it is very rich in
lymphoid follicles.
On the inferior
surface ,it is thin and
smooth. Numerous
glands both mucous
and serous lie deep
to the mucous
membrane.

43. Foliate papillae
Consist of 4 to 11 parallel ridges
that alternate with deep
grooves in the mucosa. They
contain serous glands
underlying the taste buds
which cleanse the grooves
Circumvallate papillae
Ducts of von Ebner glands
(serous salivary glands) open into
the grooves. Taste buds are seen
lining the walls of the papillae.

44. Filiform papillae
Fungiform papillae

45. Glands of BlandinNuhn
Anterior lingual glands (also
called apical glands) are
deeply placed seromucous
glands that are located near
the tip of the tongue on each
side of the frenulum linguae.
They are found on the under
surface of the apex of the
tongue.

46. GLANDS OF VON EBNER
 Serous salivary glands
 Located adjacent to the
circumvallate and foliate
papillae.
 Secrete lingual lipase.
 The secretion from these glands
flushes material from the base
of the grroves to enable the
taste buds to respond rapidly to
changing stimuli.

47. GLANDS OF WEBER
 They lie along the lateral border of the tongue.
 These glands are pure mucous secreting glands.
 These open into the crypts of the lingual tonsils on
the posterior tongue dorsum.

48. Taste buds
 Unique sense organs that contain the
chemical sense for taste.
Microscopically visible barrel-shaped
bodies found in the oral epithelium .
 Usually associated with papillae of the
tongue.Also seen in soft palate,
epiglottis, larynx, and pharynx .
 Each taste bud has ~ 10 to 14 cells.
Majority are taste cells with elongated
microvilli that project into the taste
pore.

49.  Modified columnar elongated cells
that act as receptors.
 ‘Darkly-stained' elongated central
nuclei.
 The superficial part of these cells is
provided with short hairs (hairlets or
microvilli).
 The base of the taste cells is
surrounded by sensory nerve fibres,
carry the impulses of taste sensation
to the brain.
Neuroepithelial taste cells or gustatory cells in
taste buds

50. Supporting cells in taste buds
 Elongated columnar cells with dark
cytoplasm and lightly-stained
nuclei.
 Form the outer wall of the
taste bud.
 Long microvilli extend from their
surfaces into the taste pore.
Basal cells
 Act as stem cells for renewal of taste
cells and supporting cells.

51. Clinical examination of tongue
Inspection
The tongue is examined using both direct and indirect vision. It is
examined for:
o Colour
o Swelling
o Ulcer
o Coating
o Size variation
o Crenations
o Fissures
o Atrophy or hypertrophy of papilla
o Frenal attachment and deviations as patient moves the tongue
out.

52. Examination of the lateral borders of
the tongue.
Proper use of the mirror to aid in the
visual examination of the tongue.
Visually examine the ventral surface of
the tongue.
Visually examine the dorsal surface of
the tongue.

53. PALPATION
Grasp the tip of the tongue with gauze while
palpating the body of the tongue.

54. DEVELOPMENTAL DISTURBANCES
OF TONGUE
Aglossia and Microglossia Macroglossia

55. Ankyloglossia
Fissured tongue
Cleft tongue

56. Median rhomboid glossitis
It is an asymptomatic elongated erythematous patch
of artophic mucosa on the middorsal surface of the
tongue.
 Etiology :It has been described as a congenital
abnormality of tongue due to failure of tuberculum
impar to retract before fusion of lateral halves of
tongue so that structure devoid of papillae is
interposed between them.
It is a focal area of susceptibility to chronic infections
by candida albicans

57. Lesion appears ovoid, diamond rhomboid shaped
reddish patch on dorsal surface of tongue immediately
anterior to circumvallate papillae.
It appears as a flat or slightyly elevated area and stands
out distinctly from rest of tongue because it has no
filliform papillae .
Kissing lesions are seen.

58. Geographic tongue
o Benign migratory glossitis is a
psoriasiform mucositis of the dorsum of
the tongue.
o It is characterized by constantly changing
serpignious white lines.
o It surrounds areas of smooth depapillated
mucosa.
o Becomes more prominent during
psychological stress and fund more
commonly in persons with psoriasis of
skin.

59. Black hairy tongue
Hairy tongue is a condition of defective
desquamation of the filiform papillae .
Etiology : Due to hypertrophy of the
papillae on the dorsal surface of the
tongue, usually due to lack of
mechanical stimulation and debridement.
Often occurs in individuals with poor
oral hygiene.
Other contributory factors include tobacco
use, tea or coffee drinking which accounts
for various colors associated with it.

60. Filiform papillae become 15mm in length.
Retention of food debris between the elongated paillae may
result in halitosis.
Patients may frequently complain of tickling sensation in
the soft plate and the oropharynx during swallowing.
 Overgrowth of candida albicans may result in
glossopyrosis.
The only treatment of the condition is to keep the tongue
as clean as possible by using a toothbrush or a tongue
scraper.

61. LINGUAL THYROID NODULE
It is an anomalous condition in which follicles of thyroid
tissue are found in the substance of the tongue.
Etiology :It occurs when thyroid anlage that failed to
migrate to its predestined position or from anlage remnants
that became detached and were left behind.
It appears as a nodular mass in or near the base of tongue just
posterior to foramen caecum.
Chief symptoms are dysphagia, dyspnea, dysphonia or fullnes
of throat.

62. Treatment :
o Surgical excision
o Suppresive therapy with supplemental thyroid
hormone can reduce the size of the lesion.

63. Functions of tongue
 Mastication:
The tongue an important accessory organ in the digestive system.
It is used for crushing food against the hard palate, during
mastication and manipulation of food for softening prior to
swallowing.
 During mastication food is converted into bolus and is placed on
tongue, series of muscular waves travelling posteriorly along the
tongue, passes the food over epiglottis into the oesophagus.

64.  Speech
 Speech is the mechanical process of producing audible
sounds to represent language.
 The intrinsic muscles of the tongue enable the shaping of
the tongue which facilitates speech.
 Voice is mainly produced in larynx and modified by tongue
by constantly altering its shape, position by contacting lips,
teeth, alveolar processes, hard palate and soft palate.

65.  Articulation
Articulation, in phonetics, a configuration of the vocal tract
resulting from the positioning of the mobile organs of the vocal
tract (e.g., tongue) relative to other parts of the vocal tract that
may be rigid (e.g., hard palate).
This configuration modifies an airstream to produce the sounds
of speech.
 The tongue is the principal articulator and changes position and
shape for the pronunciation of each of the vowels and
consonant.
 In pronouncing, the tongue contacts a specific part of the teeth,
alveolar ridge, or hard palate

66. Consonant sounds are most important from the dental point of
view. They may be classified according to the anatomic parts
involved in their formation:
(1) Palatolingual sounds: formed by tongue and hard or soft palate
(2) Linguodental sounds: formed by the tongue and teeth
(3) Labiodental sounds: formed by the lips and teeth
(4) Bilabial sounds: formed by the lips.
PHONETICS IN DENTURES
CLASSIFICATION OF CONSONANTS BASED ON THE PLACE
OF THEIR PRODUCTION

67.  S- the sound ‘s’ as in sixty six- is formed by a hiss of air as it
escapes form the median groove of the tongue when the tongue
is behind the upper incisor.
 The essential factor in the production of a correct s is the proper
grooving of the tongue.
 As the depth of this groove is decreased, s is softened toward sh,
and as the groove is further decreased, toward th as a lisp.
 Excessive thickness of the denture base in the anterior part of the
palate is often the cause of lisping
PALATOLINGUAL SOUNDS FORMED BY TONGUE
AND HARD PALATE

68. Where the groove of the tongue is too deep, the patient may
whistle when making the sound s.
If the patient whistles, the depth of the groove of the tongue
should be decreased by thickening the denture base in the
appropriate area.
The exact position of the groove in the tongue in relation to
the palate can be determined by making a palatogram with the
upper trial denture.

69. PALATOLINGUAL SOUNDS SOUNDS FORMED RY
TONGUE AND SOFT PALATE
This group of sounds includes k, ng and g (hard).
the sound k is formed by raising the back of the tongue to
occlude with the soft palate and then suddenly depressing
the middle portion of the back of the tongue, releasing the
air in a puff.
If the posterior border of the upper denture is
overextended or does not make firm contact with the tissue
at the posterior palatal seal, the k becomes altered toward
the German ch sound.

70. LINGUODENTAL SOUNDS
 Consonant Th is representative of the
linguodental group of sounds
Dental sounds are made with the tip of
the tongue extending slightly between
the upper and lower anterior teeth.
The words this, that, these, and those
will provide information as to the
labiolingual position of the anterior
teeth.
If about 3mm of the tip of the tongue is
not visible, the anterior teeth are
probably too far forward.

71. Tongue Position
 Class 1 – Tongue lies in the
floor of mouth with the tip
forward and slightly below the
incisal edges of mandibular
anterior teeth.
 It has the most favorable
prognosis as adequate border
seal can be achieved because
floor of the mouth will be high
enough to cover the lingual
flange.
-By CR Wright

72. Class 2 – The tip is in a
normal position but the
tongue is broadened and
flattened.

73. Class 3 – The tongue is
retracted and depressed into the
floor of the mouth with the tip
curled upward, downward or
assimilated into the body of
tongue.
Its very unfavorable position as
an adequate border seal can’t be
achieved. An attempt to extend
the flange to gain border seal
results in overextension during
tongue movements that would
dislodge the denture.

74. Role of tongue during impression
making
Making adequate retention in
mandibular denture can be achieved
if lingual surface is so designed that
the denture maintains contact seal
with tongue and floor of mouth not
only at rest, but also in function.
 Tongue position and the degree of
freedom provided for tongue
movements during border molding
procedures also play an important
role in positioning of the denture
borders, design of the denture
flange thus influencing stability of
the mandibular denture.

75. Sublingual crescent
area/Anterior lingual sulcus :
o Ask the patient to protrude the
tongue. This movement will
activate the posterior fibers of the
genioglossus muscle. The anterior
region of the floor of the mouth is
raised to determine the length
(height) of the lingual flange in
the anterior lingual sulcus.

76.  Ask the patient to retract his tongue. This will activate
the anterior fibers of genioglossus muscle. The border
molding material will be compressed between the
ventral surface of the tongue on one side and the
lingual surface of the mandible on the other. Thus the
width of the border in the anterior lingual sulcus will
be determined.

77. The mylohyoid region
o The region of the mylohyoid extends from the pre mylohyoid
fossa to the distal end of the mylohyoid ridge.
o Developing the border seal :Ask the patient to protrude the
tongue, followed by swallowing action.
o The mylohyoid muscle is activated and the floor of the
mouth is raised to contact the material. The border is
molded by the action of the mylohyoid muscle on the
borders of the tray.

78. Developing Contour of the border in Retromylohyoid
curtain region :
o Add border molding material on the disto lingual aspect of
the custom tray
o Place the tray in the mouth and ask the patient to protrude
the tongue and then close the lower jaw.
o Protruding the tongue activates the superior constrictor
muscle which molds the disto lingual border of the denture

79. Post-Insertion Problems Related To Tongue
Displacement of mandibular denture.
The most common complaint of complete denture patients
concerns the “looseness” of mandibular denture.
Patient should be made aware of the importance of tongue
position in maintaining denture retention and stability. Proper
tongue position should be demonstrated to the patient while he
looks in a mirror.
Patient should be made to practice opening and closing while
tongue assumes a normal position. Once practiced, the
enhancement of mandibular denture stability reinforces the
normal position.

80. CONCLUSION
 Knowledge of anatomy, physiology and functions of
tongue is an essence to understand the complex
morphological and functional changes in the tongue
with aging or with complete and partial edentulism.
 This knowledge will help us to reach optimal
prosthetic success, as tongue plays significant and
perhaps the dictating role in affecting stability and
retention of prostheses.

81. References
 Shafer'S Textbook Of Oral Pathology (6Th Edition).2009;pg 27-32.
 Inderbir singh.Human Embryology (8Th Edition) 2007 ;pg142-146.
 B D Chaurasia. Human Anatomy Head Neck Brain (4Th Edition)
Volume3 ,2004.pg249-254.
 Orban’s Oral Histology and Embryology, 11/e
 Zarb G A, Bolender C L – Prosthodontic treatment for edentulous
patients: Complete dentures and implant supported prostheses.
12th ed St. Louis: Mosby; 2003.p84-314.

82.  Dhananjay G, Siddiqui A , Gangadhar SA and Lagdive SB.
Anatomy of the Lingual Vestibule and its Influence on Denture
Borders. Anat Physiol.2013;3:122.
 Kaur B, Gupta G, Sandhu N, Sandhu Sarabjeet, Kaur G, Gupta T.
Tongue: The most disturbing element in mandibular denture-
How to handle it?. Annals of Dental Research 2012; 2 (1): 36-43.
 Lott F, Levin B. Flange technique: an anatomic and physiologic
approach to increased retention, function, comfort, and
appearance of dentures. J Prosthet Dent.1996:16;394-413.
 Rothman R; Phonetic consideration in denture prosthesis, J
Prosthet Dent;1961;11:214-223.

83. THANK YOU