dental embry, histo, and anatomy ch 9-10 quiz

oral mucosa properties

• continuously lines the oral cavities and serves as a “mirror” for the health of the rest of the body

• composed of stratified squamous epithelium overlying lamina propria and sometimes a deeper submucosa

• basement membrane lies between epithelium and connective tissue

• three main types:

  • lining

  • masticatory

  • specialized

nonkeratinized epithelium

• lining mucosa

• basal, intermediate, and superficial layers present

orthokeratinized mucosa

• masticatory mucosa

• basal, prickle, granular, keratin layers present

• more layers superficial to basal layer

• CELLS CONTAIN ONLY KERATIN AND NO NUCLEI!!

parakeratinized epithelium

• masticatory mucosa

• basal, prickle, granular, keratin layers

• CELLS CONTAIN KERATIN AND NUCLEI

keratinocytes

• epithelial cells in oral mucosa that produce keratin in low levels or higher levels when the tissue becomes traumatized

nonkeratinocytes

• cells that do not produce keratin

• present in much smaller numbers in oral mucosa

keratin

• waterproof protein

• tough, fibrous, opaque, waterproof protein that is impervious to pathogenic invasion and resistance to friction

• produced during maturation of keratinocyte epithelial cells as they migrate from basement membrane upwards

microplicae

• cellular ridge-like folds

• microridges known to be typical of the surfaces of the body covered with protective mucus, or in the case of the oral cavity, saliva

• superficial surface layer of most epithelium in oral mucosa contain these

lining mucosa

• covers 60% of the mouth

• made of nonkeratinized stratified squamous epithelium

• noted for its softer surface texture, moist surface, ability to stretch, act as cushion

  • buccal mucosa

  • labial mucosa

  • alveolar mucosa

  • mucosa lining of the ventral surface of tongue

  • floor of mouth

  • soft palate

lining mucosa basal layer

• also known as stratum basale

• deepest of the three epithelial layers

• single layer of cuboidal epithelial cells overlying basement membrane

• produces basal lamina of basement membrane

• germative due to mitosis of epithelial cells

lining mucosa intermediate layer

• stratum intermedium

• layer of epithelium superficial to the basal layer in nonkeratinized epithelium

• composed of larger, stacked, polyhedral-shaped cells

• larger, plumper, more fluid within cytoplasm

lining mucosa superficial layer

• stratum superficiale

• most superficial level in nonkeratinized epithelium

• layer shows even larger similarly stacked polyhedral epithelial cells, with outer layer flattening into squames

• squames shed as they age and die during turnover of tissue

clinical appearance of labial and buccal mucosa

• both appear as an opaque, pink color, shiny, moist, compressible tissue that stretches easily

• areas of melanin pigmentation may be noted

• epithelium is thick, and overlies a lamina propria with an extensive vascular supply which give it such a red color

fordyce spots (granules)

• variable number of these are scattered throughout the tissue

• are a variant usually present in the oral cavity, which are visible as small, yellowish bumps on the surface of oral mucosa

• correspond to deposits of sebum from misplaced sebaceous glands in submucosa

hyperkeratinization

• nonkeratinized epithelium may transform into keratinizing type in response to frictional or chemical trauma

• in which case, it undergoes hyperkeratinization

linea alba

• a change to hyperkeratinization commonly occurs on the usually nonkeratinized buccal mucosa when _ _ forms

• a white ridge of calloused tissue that extends horizontally at the level where the maxillary and mandibular teeth come together to occlude

alveolar mucosa clinical appearance

• reddish-pink tissue with blue vascular areas

• shiny, moist region which is extremely mobile (allows you to stretch lips) and lines the vestibules of the oral cavity

• lining mucosa

alveolar mucosa histology

• epithelium is extremely thin nonkeratinized epithelium that overlies but does no obscure

• an extensive vascular supply in the lamina propria making mucosa redder than the labial or buccal mucosa

• connective papillae are sometimes absent and numerous elastic fibers are present in the lamina propria allowing mobility

• minor salivary glands in submucosa

clinical appearance of the ventral tongue and floor of mouth

• both appear as a reddish-pink tissue with vascular blue areas of veins

• moist, shiny, compressible

• floor of the mouth has mobility, ventral surface of tongue firmly attached with some stretching

• lining mucosa

floor of mouth clinical appearance

• lingual frenum is a midline fold of tissue between ventral tongue and floor of mouth

• ridge of tissue on each side of the floor, sublingual fold, joins in a V-shape

• small papilla, sublingual caruncle, at the anterior end of each sublingual fold contains openings of the submandibular and sublingual ducts from both salivary glands

mandibular torus

• tori

• located on the lingual aspect of the mandibular arch

• present bilaterally in the area of premolars

• covered in oral tissue and of hereditary etiology

ankyloglossia

• short lingual frenum attachment that extends to tongue’s apex

• restricts movement of the tongue to varying degrees

soft palate clinical appearance

• posterior part of palate is a deep pink with yellowish hue

• compressible and elastic for speech and swallowing

• lining mucosa

soft palate histology

• thin nonkeratinized epithelium overlying a thick lamina propria

• lamina propria has numerous connective tissue papillae and distinct elastic layer for mobility

• submucosa is extremely thin and has a firm attachment to underlying muscle for speech and swallowing. contains adipose CT (yellow color) and minor salivary glands

masticatory mucosa

• noted for rubbery surface texture and resiliency

• includes hard palate, attached gingiva, and dorsal surface of tongue

• associated with orthokeratinized statified squamous epithelium parakeratinized stratified squamous epithelium

• absent submucosa

masticatory mucosa: orthokeratinized stratified squamous epithelium

• demonstrates a keratinization of the epithelial cells throughout most superficial layers

• hard palate

• attached gingiva

• specialized mucosa of the lingual papillae on the dorsal surface of tongue

orthokeratinized stratified squamous epithelium basal layer

• stratum basale

• single basal layer undergoing mitosis

• produces basal lamina of the adjacent basement membrane

orthokeratinized stratified squamous epithelium prickle layer

• stratum spinosum

• superficial to basal layer

• cells migrate to this superior level in tissue and lose ability to undergo mitosis

orthokeratinized stratified squamous epithelium granular layer

• granular layer known as stratum granulosum

• superficial to prickle layer

• epithelial cells in this layer are flat and stacked in a layer three to five cells thick

• each cell has nucelus with prominent keratohyaline granules

orthokeratinized stratified squamous epithelium keratin layer

• most superficial layer

• stratum corneum

• shows a variable thickness depending on oral cavity region

• cells are flat and have no nuclei, increasingly flatten and eventually shed

• cytoplasm filled with keratin

keratohyaline granules

• complex

• forms chemical precursor for keratin which is a soft, opaque, waterproof protein

• appear microscopically as dark spots

hard palate clinical appearance

• anterior part of palate appears as whiter-pink tissue that is immobile and firm

• cushioned feeling is noted when hard palate palpated in posterior lateral zones and firmer in the medial zone as a result of the absence of submucosa in the middle

• lateral zones consists of submucosa and salivary glands

• masticatory mucosa

hard palate histologic feature

• thick layer of orthokeratinized epithelium overlying thick lamina propria

• only lateral zones have a submucosa overlying the bones of the palate, giving the tissue here a cushioned feeling when palpated

• submucosa in anterior part of lateral zone contains adipose

• submucosa in posterior part of lateral zone contains salivary glands

• oral mucosa directly attached to periosteum of the underlying bone of hard palate

mucoperiosteum

• a structure consisting of a mucous membrane combines with the periosteum of the adjacent bone

palatine rugae and median palatine raphe have histologic features similar to those of the __ zone of the hard palate

medial

palatal torus

• variation noted in the midline of the hard palate

• developmental growths of bone with a hereditary etiology

• vary in size, slow growing, asymptomatic, may be seen on radiographs

nicotinic stomatisis

• lesion associated with salivary glands

• hard palate whitened by hyperkeratinization due to heat from tobacco use or hot liquid consumption

masticatory mucosa: parakeratinized stratified squamous epithelium

• associated with masticatory mucosa of the attached gingiva in higher levels

• it is also associated with specialized mucosa of the lingual papillae on the dorsal surface of tongue

• basal → prickle→ granular→ keratin

• granular layer may be indistinct or absent all together

• cells of the keratin layer contain not only keratin but NUCLEI

• attached gingiva and mucogingival junction

clinical appearance of attached gingiva

• opaque pink, and areas of melanin pigmentation may be present

• when dried, tissue is dull, firm, and immobile

• masticatory mucosa

• stippling observed

stippling

• observed clinically as small pinpoint depressions, which give the surface of the attached gingiva an orange-peel appearance

attached gingiva histologic feature

• thick layer of mostly parakeratinized epithelium that obscures the extensive vascular supply in the lamina propria making the tissue appear opaque and pinkish

• lamina propria has tall and narrow connective tissue papillae (noted as stippling)

• no submucosa present

• directly attached to underlying alveolar process of jaws

mucogingival junction clinical appearance

• sharply defined, scalloped unction between the pinker attached gingiva and the redder alveolar mucosa

mucogingival junction histologic feature

• can be seen as a diving zone between keratinized attached gingival tissue and nonkeratinized alveolar mucosa and thus between a masticatory mucosa and a lining mucosa

• junction between a tissue with thick epithelial layer in the pinkish attached gingiva and a tissue with a thin epithelial layer in the redder alveolar mucosa, even though both tissue types have a similar extensive vascular supply

exostoses

• variation noted usually on the facial surface of the alveolar process of the maxilla

• localized developmental growth of bone with hereditary etiology

periodontal disease

• marginal and attached gingiva can become enlarged, especially the interdental papilla

• results from edema occurring in lamina propria of the tissue because of inflammatory response

• fluid from the lamina propria capillaries flow out to flush area of injurious agents

gingival recession

• with its lower or more apical gingival margin can also result from periodontal disease, tooth position, abrasion by incorrect toothbrushing, and strong frenal attachments, abfraction from occlusal tresses such as parafunctional habits, aging

gingival graft

• reduces the amount of gingival recession

• subepithelial connective tissue graft is from lamina propria that is taken from attached gingiva then grafted directly to root

• surrounding tissue migrates to cover graft and heal area

gingival hyperplasia

• effects both epithelium and lamina propria

• overgrowth of interproximal gingiva caused by the intake of certain drugs for seizure control, certain antibiotics, and specific hear medications

lamina propria of oral mucosa

• all forms of epithelium of the oral mucosa have this layer deep to basement membrane

• main fiber group is type 1 collagen

• have papillary and dense layers

• most common cell is the fibroblast

papillary layer of lamina propria

• more superficial layer of lamina propria

• loose connective tissue along with blood vessels and nerve tissue

• equal amount of fibers, cells, and intercellular substance

dense layer of lamina propria

• deeper layer of lamina propria

• dense connective tissue with a large number of fibers

between the papillary layer and deeper layers of lamina propria is a __ __

• capillary plexus

fibroblasts

• synthesize certain types of protein fibers and intercellular substance

submucosa

• may or may not be present deep to the dense layer of lamina propria depending on the region of the oral cavity

• if present, it usually contains loose connective tissue and may contain adipose connective tissue or salivary gland

• may overlie bone or muscle within oral cavity

salivary gland histology

• both major and minor salivary glands are compose of both epithelium and connective tissue

• connective tissue of gland is divided into the capsule which surrounds the outer portion of the entire gland

• each septum helps divide the inner portion of the gland into larger lobes and smaller lobules

secretory cells

• epithelial cells that produce the saliva

• mucous cells

• serous cells

• found in a group or acinus

• each consists of a single layer of cuboidal epithelial cells surrounding a lumen

lumen

• central opening

• where the saliva is deposited after being produced by secretory cells

ranula

• retention of saliva in the gland can result in this if it involved the sublingual salivary gland

• lesion is managed by removal of the stone or surgical removal of gland

melanocytes

• forms melanin

• derived from neural crest cells

melanosomes

• melanocytes have a small cytoplasmic granules or inclusions called __ which store melanin pigment

• inject these granules into neighboring newly formed epithelial cells of basal layer

hard palate turnover time

24 days

floor of mouth turnover time

20 days

buccal and labial mucosa turnover time

14 days

attached gingiva turnover time

10 days

taste bud turnover time

10 days

junctional epithelium (attached to tooth) turnover time

4 to 6 days

granulation tissue

• immature connective tissue

• fewer fibers; increased blood vessels

• may become abundant and interfere with repair process

delay in healing

• assumptions should never be made of the source of lesion

• followed with microscopic study is only effective way to diagnose lesion

• a delay of approximately 2 weeks to allow a lesion to undergo healing

lingual tonsil

• posteriorly on the dorsal surface of the base of the tongue

• irregular mass of tissue

sulcus terminalis

• v shaped line

• divides the tongue into an anterior two thirds and posterior one third

foramen cecum

• where the sulcus terminalis points backward toward the pharynx

• a small pit like depression

median lingual sulcus

• dorsal surface

• midline depression of tongue

• corresponding to the position of a midline fibrous structure deeper in the tongue and fusion tissue area

pharyngeal part of tongue

• base of tongue

• attaches to floor of mouth and does not lie within oral cavity proper

• part of pharynx

body of tongue

• anterior two-thirds of the tongue

• lies within oral cavity proper

• contains tastebuds

ventral surface of tongue

• underside of tongue

• noted for its visible large blood vessels which pass close to surface

• plica fimbriata lingual to deep lingual vein - fringelike projections

tongue histologic features

• dorsal has both masticatory mucosa of orthokeratinized stratified squamous epithelium and specialized mucosa

specialized mucosa

• found on the dorsal surface and is associated with lingual papillae

• small discrete structures or appendages of keratinized epithelium with both orthokeratinized and parakeratinized epithelium present overlying a lamina propria

taste bud

• barrel shaped organ of taste derived from epithelium

• 30 to 80 spindle shaped cells that extend from the basement membrane of the oral mucosa to the epithelial surface of lingual papilla

• supporting cells

• taste cells that have taste pores

supporting cells

• maintain taste bud and are usually located on outer part

taste cells

• usually located on the central part and have superficial taste receptors that are responsible for making contact with dissolved molecules of food and producing a taste sensation

taste pore

• dissolved molecules of food contact the taste receptor

• opening in the most superficial part

• associated with sensory neuron processes among the cells in the inferior part

  • messages then sent to CNS and identified

filiform lingual papillae

• most common

• fine-pointed cones giving tongue velvety texture

• mechanical

fungiform

• lesser number

• mushroom-shaped red dots

• thin layer of keratinized epithelium overlying core of lamina propria with taste buds on most superficial part

• taste

foliate

• 4 to 11 vertical ridges on lateral surface of posterior tongue

• leaf-shaped structure of keratinized epithelium overlying core of lamina propria with taste buds in superficial lateral part

• taste

circumvallate

• 7-15

• large raised mushroom shaped structures anterior to sulcus terminalis

• similar histology to fungiform but also sunken deep to tongue surface

• surrounded by trough with von Ebner minor salivary glands in submucosa

geographic tongue

• appears as red and then paler pink to white patches on body of tongue

• change shape with time resembling geographic map

black hairy tongue

• usual level of shedding of epithelium of filliform lingual papillae does not occur

• thick layer of dead cells and keratin builds up on tongue surface which becomes extrinsically stained by tobacco, medicine, or chromogenic oral bacteria

most common sites of oral cancer is

• lateral border of tongue

• lesion is normally asymptomatic but can be painful as lesion invades nerve tissue

periodontal therapy purpose

• all of the periodontal therapy initiated and homecare instruction given are for the purpose of creating a healthy environment for the gingival tissue

• even with restorative treatment, the impact on the gingival tissue must be considered to ensure the restoration’s longevity

attached gingiva anatomy

• gingival tissue that tightly adheres to the bone around the roots of the teeth

• masticatory mucosa

• pink in color with melanin pigmentation possible

• stippling

interdental gingiva

• the gingival tissue between adjacent teeth

• extension of attached gingiva

• forms the interdental papillae

col

• nonvisible concave shape between the facial and lingual gingival surfaces (lies on interdental gingival)

• varies in depth and width depending on the expanse of the contacting tooth surface

• two teeth HAVE to be beside each other to have this

• nonkeratinized tissue

attached gingiva width for incisor region

• greatest usually in width

• 3.5 to 4.5 mm for maxillary

• 3.3 to 3.9 mm for mandibular

attached gingival width for posterior region

• narrowest

• 1.9 mm and 1.8 mm on maxillary posterior and mandibular first premolars

marginal gingiva anatomy

• at the gingival margin of each tooth

• free gingival

• follows scalloped pattern established by the contour of the CEJ of teeth

• similar in clinical appearance to attached gingival

• masticatory mucosa

• more translucent than attached

• mobile and free of underlying tooth surface which can be demonstrated with periodontal probe or blowing air into sulcus

marginal gingiva width

• varies

• 0.5 mm to 2.0 mm from the free gingival crest to attached gingival

free gingival groove

• separates the attached gingiva from marginal gingiva

  slight depression on the outer surface of gingiva does not correspond to the depth of sulcus but rather to the apical border of junctional epithelium

• masticatory mucosa

attached gingiva histology

• has an overlying thick layer of mostly parakeratinized stratified squamous epithelium, which obscures its extensive vascular supply in the underlying lamina propria

• pink tissue

• lamina propria has tall narrow connective tissue papillae alternated with rete ridges, highly interdigitated

• lamina propria directly attached to the underlying bone jaws

marginal gingiva histology

• overlying surface layer of only orthokeratinized stratified squamous epithelium

• underlying lamina propria has tall narrow papillae, continuous with the lamina propria of the gingival tissue that faces the tooth

• is not attached to the underlying bony alveolar process → firm but mobile

• nonkeratinized col

• gingival fiber group located in lamina propria of marginal gingiva

biologic width

• supracrestal tissue attachment

• the combine heights of the suprabony soft tissue which is attached to the par of the tooth cornonal to the crest of the alveolar bone

• commonly stated to be 2.04 mm

• important to position of restorative margins