1. ORAL CAVITY-1 ALL CONTENT IS COPYRIGHT © OF DR. STEVENS M.B KISAKA THIS CONTENT MAY ONLY BE USED FOR EDUCATIONAL PURPOSES BY CURRENT STUDENTS OF MAKERERE

2. Objectives 1.Recognise and describe a section of the lip, identifying the main features and constituent tissues. 2.Recognise and describe a section of the palate, distinguishing between hard and soft palate and identifying its epithelia and glands. 3.Recognise and describe a section of tongue (low power) appreciating the arrangement of epithelium, connective tissue (with fat cells), blood vessels, nerves, glands and muscle. 4.Recognise and describe the main lingual papillae (high power). 5.To be able to distinguish and describe serous and mucous lingual glands.

3. SLIDE 1 Lip (cat) At low magnification identify: oral surface aboral surface labial margin 1.0 mm

4. SLIDE 1 Lip (cat) 1.0 mm What type of epithelium covers : 1. the oral surface? 2. the aboral surface? oral surface aboral surface labial margin

5. SLIDE 1 Lip (cat) 1.0 mm oral surface aboral surface labial margin What type of epithelium covers : 1. the oral surface? stratified squamous (little keratinisation) 2. the aboral surface?

6. SLIDE 1 Lip (cat) 1.0 mm oral surface aboral surface labial margin What type of epithelium covers : 1. the oral surface? stratified squamous (little keratinisation) 2. the aboral surface? keratinised stratified squamous

7. SLIDE 1 Lip (cat) 1.0 mm At low magnification identify; on the aboral surface: hair follicles of two types; what are they?

8. SLIDE 1 Lip (cat) 1.0 mm At low magnification identify; on the aboral surface: hair follicles of two types; what are they? Sinus hair follicles and compound hair follicles. sinus hair follicles compound hairs

9. SLIDE 1 Lip (cat) 1.0 mm Identify: two types of gland. What are they? 100 µm

10. SLIDE 1 Lip (cat) 1.0 mm Identify: two types of gland. What are they? A : sebaceous glands. B : apocrine sweat glands. A A B B 100 µm

11. SLIDE 1 Lip (cat) 1.0 mm What cranial nerve might be seen in this section?

12. SLIDE 1 Lip (cat) 1.0 mm What cranial nerve might be seen in this section? The facial or seventh cranial nerve. 150 µm

13. SLIDE 1 Lip (cat) 1.0 mm What skeletal muscle is probably within this section?

14. SLIDE 1 Lip (cat) 1.0 mm What skeletal muscle is probably within this section? The orbicularis oris muscle. muscleconnective tissue

15. SLIDE 1 Lip (cat) 1.0 mm 50 µm How are these muscle fibres orientated re. the plane of the section?

16. SLIDE 1 Lip (cat) 1.0 mm 50 µm How are these muscle fibres orientated re. the plane of the section? In transverse section.

17. SLIDE 1 Lip (cat) 1.0 mm 50 µm What is this muscle’s function?

18. SLIDE 1 Lip (cat) 1.0 mm 50 µm What is this muscle’s function? It closes the lips.

19. SLIDE 2 Palate (mouse) This is a sagittal section through the head of a very young mouse. Identify: brain in cranium nasal cavity ethmoid bone (cribriform plate) hard palate soft palate skin nasopharynx palatine bone 1.0 mm

20. SLIDE 2 Palate (mouse) This is a sagittal section through the head of a very young mouse. Identify: brain in cranium nasal cavity ethmoid bone (cribriform plate) hard palate soft palate skin nasopharynx palatine bone 1.0 mm hard palate soft palate ethmoid bone skin brain nasal cavity nasopharynx palatine bone nasal turbinates

21. SLIDE 2 Palate (mouse) Another section through the head. In this section only the hard palate is present. Identify: nasal cavity ethmoid bone (cribriform plate) hard palate skin palatine bone incisor 1.0 mm

22. SLIDE 2 Palate (mouse) Another section through the head. In this section only the hard palate is present. Identify: nasal cavity ethmoid bone (cribriform plate) hard palate skin palatine bone incisor 1.0 mm hard palate nasal cavitynasal turbinates nasal opening skin with hairs ethmoid bone palatine bone incisor tooth

23. Sagittal section of horse head. With reference to the dissection class : locate the areas of hard and soft palate.

24. SLIDE 2 Palate (mouse) What type of epithelium covers the hard palate? Oral Cavity _ Dog ▪ Tongue & larynx have been removed ▪ Soft palate has been incised along the palatoglossal arches ▪ Note partially pigmented mucosa of upper lip ▪ Note ridged, pigmented mucosa of hard palate ▪ Identify : soft palate, junction of hard and soft palates 250 µm

25. SLIDE 2 Palate (mouse) What type of epithelium covers the hard palate? Keratinised stratified squamous epithelium. 100 µm 1 2 3 4 5 Stratum : 1: basale 2: spinosum 3: granulosum 4: lucidum (unclear) 5: corneum keratinised

26. SLIDE 2 Palate (mouse) What type of epithelium covers the oral surface of the soft palate? 250 µm oral cavity nasopharynx

27. SLIDE 2 Palate (mouse) What type of epithelium covers the oral surface of the soft palate? Stratified squamous epithelium. 50 µm oral cavity stratified squamous epithelium, some keratinisation

28. SLIDE 2 Palate (mouse) Junction between soft and hard palate. What glands are present in the soft palate? 50 µm 250 µm

29. SLIDE 2 Palate (mouse) Junction between soft and hard palate. What glands are present in the soft palate? Palatine glands (minor salivary gland). 50 µm 250 µm palatine glands

30. SLIDE 2 Palate (mouse) What type of epithelium covers the aboral surface of the soft palate seen here? 25 µm aboral surface

31. SLIDE 2 Palate (mouse) What type of epithelium covers the aboral surface of the soft palate seen here? Ciliated, pseudostratified columnar epithelium. 25 µm aboral surface ciliated, pseudostratified, columnar epithelium

32. SLIDE 2 Palate (mouse) What type of epithelium covers the aboral surface of the soft palate seen here? Ciliated, pseudostratified columnar epithelium. What striated muscle might be sectioned in the soft palate? 25 µm aboral surface ciliated, pseudostratified, columnar epithelium

33. SLIDE 2 Palate (mouse) What type of epithelium covers the aboral surface of the soft palate seen here? Ciliated, pseudostratified columnar epithelium. What striated muscle might be sectioned in the soft palate? Palatine muscle. 25 µm aboral surface ciliated, pseudostratified, columnar epithelium striated muscle palatine gland

34. SLIDE Demo TS Head SECTION THROUGH ORAL AND NASAL CAVITIES Identify: 1. Oral cavity. 2. Nasal cavity. 3. Nasal septum. 4. Nasal conchae. 5. Tongue. 6. Mandible. 7. Developing molars. 1.0 mm Embryonic

35. SLIDE Demo TS Head SECTION THROUGH ORAL AND NASAL CAVITIES Identify: 1. Oral cavity. 2. Nasal cavity. 3. Nasal septum. 4. Nasal conchae. 5. Tongue. 6. Mandible. 7. Developing molars. 1.0 mm Embryonic 1 22 3 4 5 6 7

36. SLIDE 3 Tongue (cat) Whole section seen at low magnification. Identify: epithelium fat (adipose) tissue large blood vessels and nerves glands lingual frenulum striated muscle- seen in longitudinal, oblique and transverse orientations. 5.0 mm

37. Tongue, larynx & pharynx – dog ▪ Dorsal view ▪ Pharynx and proximal oesophagus have been opened dorsally. Window has been cut in trachea. ▪ Identify : papillated (filiform) mucosa of tongue root, epiglottis, arytenoid cartilages & musculature, vestibulum oesophagi*, piriform recess*, limen pharyngoesophageum*, aditus laryngis, thyrohyoid bones, stylohyoid bones (transected). * Pars laryngea pharyngis.

38. Oral Cavity - Sheep 2 ▪ Skin reflected from mandible, partially reflected from maxilla. M. buccinator removed. left mandible in situ, right mandible has been transected just caudal to the mandibular symphysis; and removed following reflection of masseter, temporal & pterygoid mm. (latter apparent dorsal to the tongue) from the mandibular ramus. ▪ Tongue reflected ventrally to show papillated mucosa (what sort of papillae are apparent?) & torus linguae. ▪ Note : pigmented, ridged mucosa of hard palate, non-pigmented soft palate, mandibular incisor teeth, absence of upper incisors. 1 ▪ M. buccinator has been transected and reflected to expose gingival mucosa, buccal mucosa, tongue, premolar & molar teeth. ▪ Identify papillae of various sorts of the lingual and buccal mucosa. 1 2

39. SLIDE 3 Tongue (cat) Whole section seen at low magnification. Identify: epithelium dorsal lateral 5.0 mm

40. SLIDE 3 Tongue (cat) What type of epithelium covers the tongue? 100 µm lateral surfacedorsal surface

41. SLIDE 3 Tongue (cat) What type of epithelium covers the tongue? Keratinised stratified squamous epithelium. 100 µm lateral surfacedorsal surface

42. SLIDE 3 Tongue (cat) 100 µm lateral surfacedorsal surface On which surface of the tongue is the epithelium most keratinised and why?

43. SLIDE 3 Tongue (cat) 100 µm lateral surfacedorsal surface On which surface of the tongue is the epithelium most keratinised and why? On the dorsal surface. There is most contact on this surface.

44. SLIDE 3 Tongue (cat) 5.0 mm Whole section seen at low magnification. Identify: glands

45. SLIDE 3 Tongue (cat) Some minor salivary glands (lingual) can be seen in this section. 0.5 mm salivary gland

46. SLIDE 3 Tongue (cat) Minor salivary glands in body of the tongue. See also slide 4. 50 µm acini duct

47. SLIDE 3 Tongue (cat) 5.0 mm Whole section seen at low magnification. Identify: fat (adipose) tissue striated muscle- seen in longitudinal, oblique and transverse orientations. lingual frenulum frenulum

48. SLIDE 3 Tongue (cat) At fairly low magnification, the bundles of striated fibres forming the intrinsic muscles of the tongue can be seen cut in many orientations. 250 µm

49. SLIDE 3 Tongue (cat) Here at medium magnification striated muscle fibres can be seen cut in transverse and longitudinal section. Note the large areas of unilocular adipocytes (white fat). adipocytes 100 µm striated muscle A : TS section B : LS section A B

50. SLIDE 3 Tongue (cat) 5.0 mm Whole section seen at low magnification. Identify: large blood vessels and nerves.

51. SLIDE 3 Tongue (cat) Deep in the body of the tongue can be seen many blood vessels and nerves. Which cranial nerve innervates the intrinsic and extrinsic muscles of the tongue? 250 µm N : nerves A : arteries V : veins A A V N N

52. SLIDE 3 Tongue (cat) Deep in the body of the tongue can be seen many blood vessels and nerves. Which cranial nerve innervates the intrinsic and extrinsic muscles of the tongue? The hypoglossal or twelfth cranial nerve. 250 µm N : nerves A : arteries V : veins A A V N N

53. DEMO SLIDE Tongue injected (cat) This section of tongue has been injected with a blue dye to show the blood vessels. 5.0 mm

54. SLIDE 4 Lingual glands (mouse) Two types of salivary gland can be seen in this section. 1.0 mm dorsal surface root of tongue body of tongue

55. SLIDE 4 Lingual glands (mouse) In the body of the tongue. Within the musculature of the body of the tongue are found deep red glands in this haematoxylin & eosin stained section. glands 250 µm musculature surface papillae (filiform)

56. SLIDE 4 Lingual glands (mouse) At higher magnification: Acini of cuboidal epithelium with round basal nuclei, cytoplasm staining pink. Is this a serous or mucous gland? acini 50 µm striated muscle

57. SLIDE 4 Lingual glands (mouse) At higher magnification: Acini of cuboidal epithelium with round basal nuclei, cytoplasm staining pink. Is this a serous or mucous gland? Serous. acini 50 µm striated muscle

58. SLIDE 4 Lingual glands (mouse) In the root of the tongue. Glands seen here are of a blue-purple colour in a haematoxylin & eosin stained section. glands 250 µm

59. SLIDE 4 Lingual glands (mouse) At higher magnification: Acini with flattened basal nuclei, cytoplasm blue and of a ‘foamy’ appearance. Is this a serous or mucous gland? cells of acini with a ‘foamy’appearance 50 µm

60. SLIDE 4 Lingual glands (mouse) At higher magnification: Acini with flattened basal nuclei, cytoplasm blue and of a ‘foamy’ appearance. Is this a serous or mucous gland? Mucous. cells of acini with a ‘foamy’appearance 50 µm

61. SLIDE 5 Filiform papillae (cat) Identify the main papillae in this section. 1.0 mm

62. SLIDE 5 Filiform papillae (cat) Identify the main papillae in this section. Filiform papillae (arrowed). 1.0 mm folds in section

63. SLIDE 5 Filiform papillae (cat) Decide whether : glands : taste buds : lymphatic tissue : can be associated with these papillae. 0.5 mm

64. SLIDE 5 Filiform papillae (cat) Decide whether : glands : No taste buds : lymphatic tissue : can be associated with these papillae. 0.5 mm

65. SLIDE 5 Filiform papillae (cat) Decide whether : glands : No taste buds : No lymphatic tissue : can be associated with these papillae. 0.5 mm

66. SLIDE 5 Filiform papillae (cat) Decide whether : glands : No taste buds : No lymphatic tissue : No can be associated with these papillae. 0.5 mm

67. SLIDE 5 Filiform papillae (cat) At a higher magnification the stratified squamous epithelium of the papillae can be seen to possess a very thick heavily keratinised surface. 250 µm 50 µm

68. SLIDE 6 Circumvallate papillae (goat) Identify the main papilla in this section. 1.0 mm

69. SLIDE 6 Circumvallate papillae (goat) Identify the main papilla in this section. 1.0 mm Identify the main papilla in this section. Circumvallate (vallate) papilla (arrowed).

70. SLIDE 6 Circumvallate papillae (goat) Decide whether : glands : taste buds : lymphatic tissue : can be associated with this papilla. 250 µm

71. SLIDE 6 Circumvallate papillae (goat) Decide whether : glands : Yes taste buds : lymphatic tissue : can be associated with this papilla. 250 µm

72. SLIDE 6 Circumvallate papillae (goat) Decide whether : glands : Yes taste buds : Yes lymphatic tissue : can be associated with this papilla. 250 µm

73. SLIDE 6 Circumvallate papillae (goat) Decide whether : glands : Yes taste buds : Yes lymphatic tissue : Yes can be associated with this papilla. 250 µm

74. SLIDE 6 Circumvallate papillae (goat) Decide whether : glands : open into the moat around the papillae. taste buds : lymphatic tissue : can be associated with this papilla. 100 µm 1.0 mm

75. SLIDE 6 Circumvallate papillae (goat) Decide whether : glands : taste buds : on the sides of the papillae. lymphatic tissue : can be associated with this papilla. 50 µm 1.0 mm

76. SLIDE 6 Circumvallate papillae (goat) Decide whether : glands : taste buds : lymphatic tissue : found deeper into the papillae. can be associated with this papilla. 25 µm 1.0 mm

77. SLIDE 7 Foliate papillae (cat) Identify the main papillae in this section. 1.0 mm

78. SLIDE 7 Foliate papillae (cat) Identify the main papillae in this section. 1.0 mm Identify the main papillae in this section. Foliate papillae form a series of parallel folds. foliate papillae

79. SLIDE 7 Foliate papillae (cat) Decide whether : glands : taste buds : lymphatic tissue : can be associated with this papilla. 250 µm

80. SLIDE 7 Foliate papillae (cat) Decide whether : glands : Yes taste buds : lymphatic tissue : can be associated with this papilla. 250 µm

81. SLIDE 7 Foliate papillae (cat) Decide whether : glands : Yes taste buds : Yes lymphatic tissue : can be associated with this papilla. 250 µm

82. SLIDE 7 Foliate papillae (cat) Decide whether : glands : Yes taste buds : Yes lymphatic tissue : Some (seen here labelled L) can be associated with this papilla. 250 µm L : some lymphocytes L

83. SLIDE 7 Foliate papillae (cat) Decide whether : glands : seen deep in and between the papillae. taste buds : lymphatic tissue : can be associated with this papilla. 100 µm 1.0 mm

84. SLIDE 7 Foliate papillae (cat) Decide whether : glands : taste buds : seen on the sides of the papillae. lymphatic tissue : can be associated with this papilla. 100 µm 1.0 mm

85. SLIDE 7 Foliate papillae (cat) Decide whether : glands : taste buds : lymphatic tissue : see earlier picture. can be associated with this papilla. 100 µm 1.0 mm

86. Lecturer: Dr. MBS Kisaka Slides and Stains: Monica Nambi