complete anatomical growth and development with the anomalies

2. PRESENTED BY:
DR. DISHA SHAH
POST GRADUATE STUDENT
DEPT. OF PUBLIC HEALTH DENTISTRY

3. CONTENT
 Introduction
 Function of tongue
 Development
 Anatomy
 Papillae
 Muscles
 Arterial supply
 Venous drainage
 Lymphatic drainage
 Nerve supply
 Developmental anomalies
 Disorders

4. INTRODUCTION
• The tongue is a muscular structure that forms part of the floor of the oral
cavity and part of the anterior wall of the oropharynx.
• Its anterior part is in the oral cavity and is somewhat triangular in shape
with a blunt apex of tongue.
• The apex is directed anteriorly and sits immediately behind the incisor
teeth.

5. • The root of the tongue is attached to the mandible and the hyoid bone.
• The superior surface of the oral or anterior two-thirds of the tongue is
oriented in the horizontal plane.
• The pharyngeal surface or the posterior one-thirds of the tongue
curves inferiorly and becomes oriented more in the vertical plane.

6. • The oral and pharyngeal surfaces
are separated by a v-shaped sulcus
terminalis.
• This terminal sulcus forms the
inferior margin of the
oropharyngeal isthmus between
the oral and the pharyngeal
Pharyngeal
part
Oral
part

7. • At the apex of the v-shaped sulcus is a small depression which
marks the site in the embryo where the epithelium
invaginates to form the thyroid gland.
• In some people a throglossal duct persists and connects the
foramen cecum on the tongue with the thyroid gland in the
neck.

8. EMBRYOLOGICAL DEVELOPMENT
• Starts in the 4th month of Intrauterine life.
• Develops in relation to the pharyngeal arches in the floor of the
developing mouth.
• Proliferation of medial-most parts of mandibular arches
lingual swellings.
• Swellings are Separated by that appears in the midline.
tuberculum impar.

9. • Immediately behind the tuberculum impar,
the epithelium proliferates to form a down
growth  foramen caecum.
• Another midline swelling in relation to the
medial ends of the 2nd, 3rd & 4th arches
hypobranchial eminence.
Subdivisions:
cranial part related to the 2nd & 3rd arches 
copula.
Caudal part related to the 4th arch (forms the
epiglottis).

10. 1. Tongue develops during 4th – 8th week
of prenatal development.
2. It develops from independent swellings
formed by the first four branchial arches.
1. Body of the tongue : 1st arch
2. Base of the tongue : 3rd & 4th arch

11. Epithelium:
• Anterior 2/3: formed by 2 lingual swellings and one
tuberculum impar, i.e. from first branchial arch supplied
lingual nerve and chorda tympani
• Posterior 1/3: formed by the cranial part of the
hypobranchial eminence, i.e. from the third arch
by glossopharyngeal nerve

12. Posterior most:
• Formed by the 4th arch supplied by vagus nerve
• Muscles are supplied by hypoglossal nerve
• Connective tissue develops from local mesenchyme.

13. PARTS AND SURFACES OF THE TONGUE

14. VENTRAL SURFACE
• The thin strip of tissue that runs
vertically from the floor of the
mouth to the under surface of
the tongue is called the lingual
frenulum.
• On either side of frenulum there
is a prominence produced by
deep lingual veins. More
laterally there is a fold called
plica fimbriata.
Plica
Fimbriata
Sublingual fold on
floor of mouth
Orifice of
submandibular duct
Lingual Frenum
Lingual Nerve
Deep Lingual
vein
Anterior lingual
gland
Labial frenum

15. PHARYNGEAL
(POST SULCAL PART)
• Lies behind the palatoglossal
arches
• Forms the anterior wall of the
oropharynx
• Devoid of papillae
• Underlying lymphoid nodules
embedded in the submucosa
collectively called as lingual

16. PAPILLAE OF TONGUE

17. CIRCUMVALLATE PAPILLA
Situated in front of the sulcus terminalis
Cylindrical projection surrounded by a circular
sulcus.
Large in size 1-2mm in diameter.
8-12 in number.
Taste buds are present on the surrounding wall and
trough like depression.
Concerned with bitter taste

18. FUNGIFORMPAPILLAE
• These are mushroom shaped
• Each consists of a narrow pedicle and a large
rounded head.
• Distinguished by their bright red colour.
• Contains taste buds.
• Concerned with salty taste at the margins and
sweet taste at the tip

19. FILIFORM PAPILLAE
• Also known as conical papillae.
• Covers presulcal area of dorsum of tongue and gives it a characteristic
velvety appearance.
• Smallest and most numerous of the lingual papillae.
• Apex often split into filamentous processes.
• taste buds absent

20. FOLIATE PAPILLAE
• Rudimentary in man.
• They are present on the lateral aspect of tongue anterior to
arch.
• They occupy the area where cancerous lesions are most apparent to
on tongue and thus should be distinguished from mucosal changes that
reflect precancerous conditions.
• Nature of taste -sour

21. TASTE BUDS
• Taste buds are located on the dorsum of the tongue
and are associated with the papillae
• Appear around 8th week of IUL. Arise by inductive
interaction b/w the epithelial cells and the invading
gustatory nerve cells from chorda tympani,
glossopharyngeal and vagus nerve.
• 30-80 in number. 50-80micron in length, 30-
50micron in diameter.

22.  Each bud has 2 kinds of cell,
supporting and neuropithelial taste
cells.
 Taste buds comprise 20-50 cells.
 Within the bud, 3 major cell types have
been described.

23.  Type–i cells (80%): the cells are regarded as
serving a neurotransmitter function.
 Type-ii cells (15%): these contain neural synapses
the direction of which suggest a different
transmission from nerve to bud.
 Type-iii cells (5%): these cells are regarded as
receptor cells in the taste bud.

24. TASTE DISCRIMINATION
• Gustatory receptors detect 5 main types of taste sensation
• Sweet: tip
• Sour: middle
• Salty: anterolateral
• Bitter: base
• Umami: Centre
• However recent evidence indicates that all areas of tongue are
responsive to all taste stimuli
UMAMI

25. MUSCLES OF TONGUE
INTRINSIC MUSCLES
• SUPERIOR LONGITUDINAL
• INFERIOR LONGITUDINAL
• TRANSVERSE
• VERTICAL
EXTRINSIC MUSCLES
• STYLOGLOSSUS
• HYOGLOSSUS
• GENIOGLOSSUS
• PALATOGLOSSUS

27. EXTRINSIC MUSCLES

28. GENIOGLOSSUS MUSCLE
Main bulk of the tongue, fan shaped.
Origin:- upper genial tubercles.
Insertion :- Upper fibres - tip of tongue
Middle fibres - dorsum
Lowers fibres - hyoid bone
Actions :- Upper fibres - retract the tip
Middle fibres – depresses
Lowers fibres - protrudes
Nerve supply :- hypoglossal nerve
Hyoid

29. HYOGLOSSUS
• Origin: greater cornu of hyoid bone,
adjacent to body of hyoid bone
• Insertion: side of the tongue between
styloglossus and inferior longitudinal
• Action: depresses the tongue & makes
the dorsal surface convex.
• Nerve supply: hypoglossal nerve

30. STYLOGLOSSUS
• Origin : tip of the styloid process
• Insertion : longitudinal part into the
inferior longitudinal muscles. Oblique
part into hyoglossus.
• Action: draws the tongue upwards &
backwards.
• Nerve supply: hypoglossal nerve.
Styloid process
styloglossusInferior longitudinal
muscles
hyoglossus

31. PALATOGLOSSUS
• Origin: palatine aponeurosis of soft palate
• Insertion: side of the tongue
“More a part of soft palate than the tongue”
• Action: elevates the posterior part of the
tongue
• Bilaterally - approximates the palatoglossal
thus helps in closing the oropharyngeal
isthmus.

32. INTRINSIC MUSCLES

33. SUPERIOR LONGITUDINAL
• Origin: submucous fibrous layer below the
dorsum of the tongue and lingual septum
• Insertion: extends to the lingual margin
• Action : turns the apex and sides of the
tongue upward to make the dorsum concave
• Nerve supply: hyoglossal nerve.

34. INFERIOR LONGITUDINAL
• Narrow band lying close to the inferior
surface of the tongue. B/w the genioglossus
& the hyoglossus.
• Origin : root of tongue
• Insertion : apex of the tongue
• Shortens tongue and makes dorsum convex
• Action : curls the tip inferiorly and shortens
shortens the tongue

35. TRANSVERSE :
• Origin : median septum of the tongue
• Insertion : lateral margins of the tongue
• Action: narrows and elongates the tongue
VERTICAL :
• Origin : dorsum of the tongue
• Insertion : ventral regions of the tongue
• Action: narrows and elongates the tongue.
• Nerve supply for both the muscle is hyoglossal nerve

36. FUNCTIONS OF THE TONGUE
• Speech
• Mastication
• Deglutition
• Taste
• Jaw development
• Secretion
• Maintenance of oral hygiene
• Sucking

37. Speech: partial glossectomy can limit speech capabilities.
Mastication: carried out by the extrinsic muscles.
Deglutition: the backward movement of the food bolus as a result
of the upward and forward pressure of the tongue on the hard
palate, muscles involved in this process are the mylohyoid muscle
and the pharyngeal constrictors.

38. Taste: taste(or gustation) is a sensation that is developed well
before birth.
Prehension and ingestion: licking, sucking, all involve
coordinated muscular activity of the tongue.
Jaw development: muscular pressures from the tongue are an
important factor in developing the shape of the mandibular arch
and the position of anterior and posterior tooth segments.

39. Histology of tongue

40. MUCOUS MEMBRANE ON VENTRAL SURFACE
• It is thin, smooth and loosely attached
to the underlying connective tissue
• It is freely mobile and not raised into
papillae because epithelium is closely
closely adherent to underlying muscle
by a thin lamina propria.
• It is covered with non- keratinized
stratified squamous epithelium.

41. MUCOUS MEMBRANE ON DORSAL SURFACE
• The dorsal surface of the tongue is covered with a
mucous membrane, which is firmly adherent to the
the underlying C.T.
• It is raised into small projections similar to the
villi, but known as papillae
• The stratified squamous epithelium covering the
dorsal surface of the tongue is mostly keratinized

42. BLOOD SUPPLY
The main arterial blood supply to the
tongue is by lingual branch of the
external carotid artery, but the root of
the tongue is supplied by tonsillar
and ascending palate arteries.

43. VENOUS DRAINAGE
 The deep lingual vein is the largest
& principal vein of the tongue.
 It travels with hypoglossal nerve on
each side on the external surface of
hyoglossus muscle.
 Joins the internal jugular vein of
neck.

44. Dorsal Lingual Vein:
 It follows the lingual artery between
the hyoglossus and genioglossus
muscles.
 Drains into internal jugular vein

45. NERVE SUPPLY
Sensory supply:
• Ant 2/3rd - lingual nerve for
general sensation. Chorda
for the special sensation.
• Post 1/3rd - glossopharyngeal
• Posterior most part - vagus

46. Motor supply:
• All the intrinsic and extrinsic
muscles except the palatoglossus
are supplied by the hypoglossal
nerve.
• Palatoglossus – pharyngeal
• Fibres of this plexus form
part of accessory nerve through
the vagus.

47. LYMPHATIC DRAINAGE
• The tip of the tongue drains bilaterally to
the submental nodes.
• The right & left halves of the remaining
part of the anterior 2/3rds of the tongue
drain unilaterally to the submandibular
nodes.
• Posterior 1/3rd bilaterally to jugulo-
omohyoid nodes.

48. EXAMINATION OF TONGUE
• The patient is asked to protrude the tongue onto the
gauze. Aided by the gauze the dentist can hold the
tongue using a mirror to examine it.
• Palpation should be done both left to right & right
to left & should be done quickly.
• The targeted areas are the lateral borders & the
region of vallate papillae.

49. DEVELOPMENTAL ANAMOLIES OF TONGUE
• Ankyloglossia
• Macroglossia
• Hypoglossia
• Bifid tongue
• Fissured tongue
• Median rhomboid glossitis
• Benign migratory glossitis
• Lingual thyroid nodule

50. CONGENITAL ANOMALIES
• Aglossia: absence of tongue.Can cause
difficulty in eating and talking.
• Microglossia: as a consequence of the less
muscular stimulus between the alveolar
arches, tongue do not develop transversely
• Causing the mandible not to grow in anterior
direction resulting in dento-skeletal malocclusion.

51. MA CROGLOSSI A
( E NLARGE D T O NGUE )
• Clinical features: malocclusion
• Scalloping of lateral borders.
• Displacement of teeth.
• Associated with beckwith’s
hypoglycemic syndrome.
• Treatment: Mild – no surgery,
speech therapy
Severe – Partial glossectomy

52. ETIOLOGICAL
CONGENITAL/HERIDITARY
 LYMPHANGIOMA
 HEMANGIOMA
 CRETINISM
 DOWNS SYNDROME
ACQUIRED
 EDENTULOUS PATIENTS
 AMYLOIDOSIS
 ACROMEGALY
 ANGIOEDEMA
 CARCINOMA OR TUMOR

53. ANKYLOGLOSSIA / TONGUE TIE
• Aetiology: genetic in origin.
• Commonly associated with pierre robin syndrome.
• Two types:
1. Complete – fusion of the tongue to the floor.
2. Partial – short lingual frenum attached to the tip of the tongue.
• Clinical feature: Inferior frenum attaches to the bottom of the tongue &
restricts the free movements of the tongue
• Treatment : lingual frenectomy

54. Manual elevation of the
lingual apex by the
examiner.
• The treatment is to surgically sever the connection between the frenum
and the floor of the mouth.
• In young children treatment is postponed until 4 – 5 years
since it is difficult to access severity of disorder in early life.

55. CLEFT TONGUE/ BIFIDTONGUE
 Aetiology: Caused due to the
lack of merging of the lingual
swellings.
 Clinical feature: Food debris at
the base of the cleft which
irritation.
 treatment: Surgical
reconstruction

56. FISSURED TONGUE
(SCROTAL TONGUE)
• Etiology: often hereditary.
• Clinical features: Multiple fissures; commonly
associated with erythema migrans.
• Develops simultaneously as a sequel to
geographic tongue
• Treatment: oral hygiene care

57. MEDIAN RHOMBOID GLOSSITIS
Aetiology: congenital. It may be acquired, and is
sometimes infected with candida species.
Clinical features: rhomboidal (diamond-shaped)
red, or nodular and depapillated or white patch, in
midline of dorsum of tongue, just anterior to
circumvallate papillae.
Treatment: antifungals if candida & stop smoking.

58. BENIGN MIGRATORY GLOSSITIS
Geographic tongue, wandering rash, erythema
migrans.
Aetiology: unknown and can also be associated
with emotional stress.
Clinical features: History of migrating pattern.
Areas desquamation of filliform papillae.
Red areas change in shape, increase in size &
spread to other areas within hours.

59. LINGUAL THYROID NODULE
• Accessory accumulation of functional thyroid gland tissue within the body of
the tongue is called lingual thyroid nodule.
• Pathogenesis: embryologically thyroid gland develops as an endodermal down
growth at the site of the foramen cecum.
• It then migrates inferiorly along the thyroglossal tract to the anterolateral
surface of the trachea.
• If all or part of the thyroid analogue fails to migrate, then lingual thyroid nodule
develops, which is characterized by a mass of thyroid tissue on the mid-
posterior dorsum of the tongue.

60. • Clinical features: appears as a nodular exophytic mass, measuring
about 2 to 3 cm in diameter and is located posterior to the foramen
caecum.
• Symptoms include dysphonia, bleeding, pain, dysphagia, dyspnea
and a feeling of tightness in the throat.
• Treatment: surgical excision.

61. SJOGREN'S SYNDROME
• Clinical features: xerostomia in
sjogren's syndrome predisposes to
depapillated lobulated tongue and
candidosis.
• Treatment: sialogogues or artificial
saliva, antifungals.

62. C A N D I D A L G L O S S I T I S
• Etiology: opportunistic infection with candida species, particularly C.
Albicans.
• Types:
• Acute pseudomembranous
• Thrush
• Acute atrophic
• Antibiotic sore mouth

63. • Predisposing factors:
• Broad spectrum antimicrobials, particularly tetracycline;
• xerostomia; topical corticosteroids, immune defects.
• Clinical features:
• Diffuse erythema and soreness .
• There may also be patches of thrush particularly in upper buccal sulcus
posteriorly.
• Treatment: treat predisposing cause; antifungals

64. FURRED TONGUE
Etiology:
• Often unknown, but sometimes poor oral hygiene,
herpetic stomatitis, dehydration or soft diet.
• Debris and bacteria accumulate, especially if diet
contains little roughage.
• An upper denture also does not clean the tongue as
effectively as palatal rugae.
• Clinical features: the tongue has yellowish `fur' which
may be discolored by foods or drugs.
Treatment: treat underlying condition.

65. NEUROFIBROMA
Etiology: benign tumour arising from
specialized fibroblasts of neural sheath
Clinical features: painless slow-growing soft
mass, usually in the tongue.
• Treatment: surgical excision

66. BURNING MOUTH
(ORAL DYSAESTHESIA)
• Etiology: Several predisposing factors include organic lesions, e.g.
Deficiency states, erythema migrans, ulcers, lichen planus and
candidosis.
Clinical features: Almost invariably persistent burning sensation in
tongue (occasionally in palate) with no organic disease
• Treatment: psychotherapy or antidepressants or b vitamins, are
occasionally helpful.

67. HAEMANGIOMA
Etiology:
• Hamartoma or benign tumour.
Clinical features:
• Red or blue, painless, soft and sometimes fluctuant
lesions that usually blanch on pressure, most
appear in infancy.
Treatment:
• Surgical management

68. DEFICIENCY GLOSSITIS
Etiology:
• Deficiencies of iron, folic acid, vitamin B12 can
cause sore tongue which may appear normal, or
may be red and depapillated.
Clinical features: Tongue may appear completely
normal, or there may be linear or patchy red
lesions (especially in vitamin B12 deficiency,
depapillation with erythema (in deficiencies of
iron, folic acid or B vitamins) or pallor (iron
deficiency).
• Treatment: replacement therapy after underlying
cause of deficiency established and rectified

69. S C ARLE T F E VE R
• Etiology: beta haemolytic streptococci
• Clinical feature:
• Strawberry tongue- tongue shows a white coating, the fungiform papillae
& fungiform papillae - edematous and hyperemic.
• Raspberry tongue - The coating is lost and the tongue becomes smooth.
• Treatment: no specific treatment, antibiotics administration.

70. HAIRY TONGUE
• A condition of defective desquamation of the filliform
papillae.
Etiology: unknown. Smoking, drugs and poor oral
hygiene may predispose.
Clinical features: Brown or black hairy appearance of
central dorsum of tongue, severest posteriorly.
Treatment: Improve oral hygiene; discontinue any
drugs responsible; brushing the tongue.

71. LEUKOPLAKIA
• Etiology: 6 ‘s’
• Clinical features: milk - white patch or plaque
occurring on the surface of mucous membrane
which cannot be rubbed or stripped off
• Treatment: elimination of etiologic factor
• Vitamin therapy
• Surgical management

72. C a n di di a s i s
Etiology: candida albicans
Clinical features: appears as soft, white, slightly elevated
plaques. Resembles milk curds. The plaque is wiped away
leaving a normal mucosa or an erythematous area.
Treatment: Removal of cause
• Topical creams & ointments: e.g. Clotrimazole, nystatin, etc.
Oral rinses e.g. Mycostatin, 0.2% chlorhexidine
• Systematic treatment: e.g. Nystatin 250mg, fluconazole
100mg, etc.

73. S Q UAMOUS C E L L C A RCI NOMA
Commonly Develops on the lateral border or ventral surface.
Etiology: Chronic irritation, Pre-cancerous lesions, Betel
chewing
• Dental ulcers, Carious or broken tooth or an ill fitting
denture.
• Poor oral hygiene and mal nutrition.
Clinical feature: Painless mass or ulcer which may begin
as a superficially indurated ulcer with slightly raised
borders and may develop as a exophytic growth or to
infiltrate the deep layers of tongue.
If, Involvement of Lingual Nerve , Pain that may be referred
referred to the ear through Auriculotemporal Nerve.

74. Treatment:

75. C O L OUR C H ANG E S

76. APPLIED ANATOMY OF TONGUE
1. Injury to the hypoglossal nerve produces paralysis of the muscles of the
tongue on the side of lesion.
 If the lesion is infranuclear, there is gradual atrophy of the affected half
of the tongue or hemiatrophy.
 Supranuclear lesions of the hypoglossal nerve produce paralysis without
wasting. This is best seen in pseudobulbar palsy where the tongue is stiff,
stiff, small and moves very sluggishly resulting in defective articulation.

77. 2. Glossitis is usually a part of generalized ulceration of the mouth
cavity or stomatitis.
• In certain anaemias, the tongue becomes smooth due to atrophy of
the filiform papillae.
3. The presence of a rich network of lymphatics and of loose areolar
tissue in the substance of the tongue is responsible for enormous
swelling of the tongue in acute glossitis.
4. The undersurface of the tongue is a good site along with the bulbar
conjunctiva for observation of jaundice.

78. 5. In unconscious patients, the tongue may fall back and obstruct the air passages.
This can be prevented either by lying the patient on one side with head down or
by keeping the tongue out mechanically.
6. In patients with grand mal epilepsy, the tongue is commonly bitten between the
teeth during the attack. This can be prevented by hurriedly putting in a mouth
gag at the onset of the seizure.
7. Carcinoma of the tongue is quite common. risk factors include tobacco, alcohol,
betel quid, lower socioeconomic group, ethnic minority etc.

79.  Clinically seen as a granular ulcer with fissuring or raised exophytic
margins, red or white or combined ulcer, or as a indurated lump or
ulcer .
 The affected side of the tongue is removed surgically.
 All the deep cervical lymph nodes are also removed, i.e. block dissection of
neck.
 Carcinoma of the posterior one-third of the tongue is more
dangerous due to bilateral lymphatic spread.

80. • 8. Sharp tooth, unfinished amalgam restorations & metal crowns can
cause ulcer on tongue, one of the predisposing factor for tongue cancer
• 9. Paralysis of genioglossus: when the genioglossus is paralyzed, the
tongue mass has a tendency to shift posteriorly, obstructing the airway
and presenting the risk of suffocation. Total relaxation of the genioglossus
muscles occurs during general anaesthesia, therefore, the tongue of an
anesthetized patient must be prevented from relapsing by inserting an
airway.

81. • 10. Sublingual absorption of drugs: For quick transmucosal absorption
are drug for instance, when nitroglycerin is used as a vasodilator in
angina pectoris the pill (or spray) is put under the tongue where the
thin mucosa allows the absorbed drug to enter the deep lingual veins in
less than a minute.

82. R E F E R E N C E S
• Human anatomy – by B D chaurasia, 3rd vol, 4th edition, pg 166-171
• Grays anatomy for students – by drake, vogl & mitchell, pg 989-996
• Craniofacial embyology- by G H sperber, 3rd edition, pg 154-159
• A color atlas of the tongue in clinical diagnosis - beaven & brooks
• Burket’s oral medicine - by lynch, brightman & greenberg, 8th
edition, pg 431-480
• Shafer’s text book of oral pathology – 5th edition, pg 36-44, 436,1168