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 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. SLIDE 1 Lip (cat) At low magnification identify: oral surface 1.0 mm aboral surface labial margin SLIDE 1 Lip (cat) What type of epithelium covers : 1. the oral surface? 2. the aboral surface? oral surface labial margin 1.0 mm aboral surface SLIDE 1 Lip (cat) What type of epithelium covers : 1. the oral surface? 2. the aboral surface? oral surface labial margin 1.0 mm aboral surface stratified squamous (little keratinisation) SLIDE 1 Lip (cat) What type of epithelium covers : 1. the oral surface? 2. the aboral surface? oral surface labial margin 1.0 mm aboral surface stratified squamous (little keratinisation) keratinised stratified squamous SLIDE 1 Lip (cat) At low magnification identify; on the aboral surface: hair follicles of two types; what are they? 1.0 mm SLIDE 1 Lip (cat) 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 1.0 mm compound hairs SLIDE 1 Lip (cat) Identify: two types of gland. What are they? 100 µm 1.0 mm SLIDE 1 Lip (cat) Identify: two types of gland. What are they? A : sebaceous glands. B : apocrine sweat glands. B A 100 µm B A 1.0 mm SLIDE 1 Lip (cat) What cranial nerve might be seen in this section? 1.0 mm SLIDE 1 Lip (cat) What cranial nerve might be seen in this section? The facial or seventh cranial nerve. 150 µm 1.0 mm SLIDE 1 Lip (cat) What skeletal muscle is probably within this section? 1.0 mm SLIDE 1 Lip (cat) What skeletal muscle is probably within this section? The orbicularis oris muscle. muscle 1.0 mm connective tissue SLIDE 1 Lip (cat) How are these muscle fibres orientated re. the plane of the section? 50 µm 1.0 mm SLIDE 1 Lip (cat) How are these muscle fibres orientated re. the plane of the section? In transverse section. 50 µm 1.0 mm SLIDE 1 Lip (cat) What is this muscle’s function? 50 µm 1.0 mm SLIDE 1 Lip (cat) What is this muscle’s function? It closes the lips. 50 µm 1.0 mm 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 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 ethmoid bone nasal turbinates skin brain nasal cavity palatine bone hard palate nasopharynx soft palate 1.0 mm 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 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 ethmoid bone nasal turbinates nasal cavity skin with hairs nasal opening palatine bone hard palate incisor tooth 1.0 mm Sagittal section of horse head. With reference to the dissection class : locate the areas of hard and soft palate. 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 SLIDE 2 Palate (mouse) What type of epithelium covers the hard palate? Keratinised stratified squamous epithelium. Stratum : 1 1: basale 2: spinosum 3: granulosum 4: lucidum (unclear) 5: corneum keratinised 2 3 5 4 100 µm SLIDE 2 Palate (mouse) What type of epithelium covers the oral surface of the soft palate? nasopharynx oral cavity 250 µm SLIDE 2 Palate (mouse) What type of epithelium covers the oral surface of the soft palate? Stratified squamous epithelium. stratified squamous epithelium, some keratinisation oral cavity 50 µm SLIDE 2 Palate (mouse) Junction between soft and hard palate. What glands are present in the soft palate? 250 µm 50 µm SLIDE 2 Palate (mouse) Junction between soft and hard palate. What glands are present in the soft palate? Palatine glands (minor salivary gland). 250 µm palatine glands 50 µm SLIDE 2 Palate (mouse) What type of epithelium covers the aboral surface of the soft palate seen here? aboral surface 25 µm SLIDE 2 Palate (mouse) What type of epithelium covers the aboral surface of the soft palate seen here? Ciliated, pseudostratified columnar epithelium. aboral surface ciliated, pseudostratified, columnar epithelium 25 µm 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? aboral surface ciliated, pseudostratified, columnar epithelium 25 µm 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. ciliated, pseudostratified, aboral surface columnar epithelium striated muscle palatine gland 25 µm SLIDE Demo TS Head Embryonic Identify: 1. Oral cavity. 2. Nasal cavity. 3. Nasal septum. 4. Nasal conchae. 5. Tongue. 6. Mandible. 7. Developing molars. 1.0 mm SECTION THROUGH ORAL AND NASAL CAVITIES SLIDE Demo TS Head SECTION THROUGH ORAL AND NASAL CAVITIES Embryonic 2 Identify: 1. Oral cavity. 2. Nasal cavity. 3. Nasal septum. 4. Nasal conchae. 5. Tongue. 6. Mandible. 7. Developing molars. 4 3 1 7 5 6 1.0 mm 2 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 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. Oral Cavity - Sheep 2 1 ▪ 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. 2 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. ▪ 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. SLIDE 3 Tongue (cat) Whole section seen at low magnification. Identify: epithelium dorsal lateral 5.0 mm SLIDE 3 Tongue (cat) What type of epithelium covers the tongue? lateral surface dorsal surface 100 µm SLIDE 3 Tongue (cat) What type of epithelium covers the tongue? Keratinised stratified squamous epithelium. lateral surface dorsal surface 100 µm SLIDE 3 Tongue (cat) On which surface of the tongue is the epithelium most keratinised and why? lateral surface dorsal surface 100 µm SLIDE 3 Tongue (cat) On which surface of the tongue is the epithelium most keratinised and why? On the dorsal surface. There is most contact on this surface. lateral surface dorsal surface 100 µm SLIDE 3 Tongue (cat) Whole section seen at low magnification. Identify: glands 5.0 mm SLIDE 3 Tongue (cat) Some minor salivary glands (lingual) can be seen in this section. salivary gland 0.5 mm SLIDE 3 Tongue (cat) Minor salivary glands in body of the tongue. See also slide 4. duct acini 50 µm SLIDE 3 Tongue (cat) Whole section seen at low magnification. Identify: fat (adipose) tissue striated muscle- seen in longitudinal, oblique and transverse orientations. lingual frenulum frenulum 5.0 mm 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 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 B striated muscle A : TS section B : LS section A 100 µm SLIDE 3 Tongue (cat) Whole section seen at low magnification. Identify: large blood vessels and nerves. 5.0 mm 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? N A N : nerves A : arteries V : veins A N V 250 µm 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. N A N : nerves A : arteries V : veins A N V 250 µm DEMO SLIDE Tongue injected (cat) This section of tongue has been injected with a blue dye to show the blood vessels. 5.0 mm SLIDE 4 Lingual glands (mouse) Two types of salivary gland can be seen in this section. dorsal surface body of tongue root of tongue 1.0 mm 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. surface papillae (filiform) musculature glands 250 µm 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? striated muscle acini 50 µm 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. striated muscle acini 50 µm 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 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 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 SLIDE 5 Filiform papillae (cat) Identify the main papillae in this section. 1.0 mm SLIDE 5 Filiform papillae (cat) Identify the main papillae in this section. Filiform papillae (arrowed). folds in section 1.0 mm SLIDE 5 Filiform papillae (cat) Decide whether : glands : taste buds : lymphatic tissue : can be associated with these papillae. 0.5 mm SLIDE 5 Filiform papillae (cat) Decide whether : glands : No taste buds : lymphatic tissue : can be associated with these papillae. 0.5 mm SLIDE 5 Filiform papillae (cat) Decide whether : glands : No taste buds : No lymphatic tissue : can be associated with these papillae. 0.5 mm SLIDE 5 Filiform papillae (cat) Decide whether : glands : No taste buds : No lymphatic tissue : No can be associated with these papillae. 0.5 mm 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 SLIDE 6 Circumvallate papillae (goat) Identify the main papilla in this section. 1.0 mm SLIDE 6 Circumvallate papillae (goat) Identify the main papilla in this section. Circumvallate (vallate) papilla (arrowed). 1.0 mm SLIDE 6 Circumvallate papillae (goat) Decide whether : glands : taste buds : lymphatic tissue : can be associated with this papilla. 250 µm SLIDE 6 Circumvallate papillae (goat) Decide whether : glands : Yes taste buds : lymphatic tissue : can be associated with this papilla. 250 µm SLIDE 6 Circumvallate papillae (goat) Decide whether : glands : Yes taste buds : Yes lymphatic tissue : can be associated with this papilla. 250 µm SLIDE 6 Circumvallate papillae (goat) Decide whether : glands : Yes taste buds : Yes lymphatic tissue : Yes can be associated with this papilla. 250 µm 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. 1.0 mm 100 µm SLIDE 6 Circumvallate papillae (goat) Decide whether : glands : taste buds : on the sides of the papillae. lymphatic tissue : can be associated with this papilla. 1.0 mm 50 µm SLIDE 6 Circumvallate papillae (goat) Decide whether : glands : taste buds : lymphatic tissue : found deeper into the papillae. can be associated with this papilla. 1.0 mm 25 µm SLIDE 7 Foliate papillae (cat) Identify the main papillae in this section. 1.0 mm SLIDE 7 Foliate papillae (cat) Identify the main papillae in this section. Foliate papillae form a series of parallel folds. foliate papillae 1.0 mm SLIDE 7 Foliate papillae (cat) Decide whether : glands : taste buds : lymphatic tissue : can be associated with this papilla. 250 µm SLIDE 7 Foliate papillae (cat) Decide whether : glands : Yes taste buds : lymphatic tissue : can be associated with this papilla. 250 µm SLIDE 7 Foliate papillae (cat) Decide whether : glands : Yes taste buds : Yes lymphatic tissue : can be associated with this papilla. 250 µm 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. L : some lymphocytes L 250 µm 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. 1.0 mm 100 µm 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. 1.0 mm 100 µm SLIDE 7 Foliate papillae (cat) Decide whether : glands : taste buds : lymphatic tissue : see earlier picture. can be associated with this papilla. 1.0 mm 100 µm Lecturer: Dr. MBS Kisaka Slides and Stains: Monica Nambi