Exam #2 Flashcards
(193 cards)
1
Q
What are the three mechanisms of cranioskeletal growth in early development?
A
- Secondary growth cartilages: allows for growth prenatal/postnatal
- Sutural growth: Postnatal growth
- Displacement growth (transposition): Postnatal growth
2
Q
Types of secondary growth cartilages:
A
- Coronoid: Incorporated before birth
- Angular: Disappears before birth
- Malar: Disappears before birth
- Symphyseal: present until 1 year
- Condylar: Present until 20 years
- Articular eminence: Present until 20 years
3
Q
Secondary growth cartilages are associated with:
A
Bones formed by intramembranous ossification
4
Q
Growth cartilages develop after:
A
Intramembranous ossification has been initiated
5
Q
secondary growth cartilages will undergo:
A
Endochondral ossification
6
Q
What are secondary growth carriages comprised of?
A
Fibrocartilage
7
Q
Adult structures in the skull are classified as:
A
Synarthroses joints (Immovable joints)
8
Q
Synostoses are:
A
Fused bone; term used to describe the adult remnant of an ossified structure
9
Q
What are the primary growth sites for membranous viscerocranium and neurocranium?
A
Sutures
10
Q
What are sutures?
A
Regions of CT between bony articulation
11
Q
What regulates suture closure?
A
Epithelial-Mesenchymal signaling
12
Q
What is Synchondroses?
A
Term used to describe suture composed of hyaline cartilage formed between bones that ossify by endochondral ossification.
13
Q
What is Syndesmoses?
A
Term used to describe a suture composed of fibrous connective tissue; Bones ossify by intramembranous ossification
14
Q
What are the 3 types of syndesmoses?
A
- Simple: Flat edge b/w bone
- Serrated: interdigitating edges b/w bone fronts
- Squamosal: overlap of bone
15
Q
What is the resting zone in synchondroses?
A
New cartilage cells in center of suture
16
Q
Describe what happens after the resting zone in synchondroses?
A
Cells move laterally passing through proliferation and into a maturate stage of hypertrophy.
Cartilage matrix surrounding chondrocytes in hypertrophy will calcification and cell dies.
The matrix of a synchondrosis will ossify by endochondral ossification.
17
Q
What are the histological features of Syndesmoses?
A
- Band of fibrous connective tissues lie between osteoprogenitor cells of periosteum
- CT of a syndesmosis will ossify by intramembranous ossification
18
Q
What are the three sutural growth sites in the cranioskeleton?
A
- Cartilaginous Neurocranium
- Membranous neurocranium
- Membranous viscerocranium
19
Q
Where do sites of sutural growth occur?
A
Synchondroses or syndesmoses joints
20
Q
What direction does sutural growth occur?
A
Perpendicular to position of the suture
21
Q
Sutural closure depends on signaling b/w:
A
CT suture and ectoderm; brain; dura
22
Q
The longer the cells remain in a proliferative state the longer the suture:
A
Remains open
23
Q
What is Craniosynostosis?
A
Premature closure of the sutures
24
Q
Premature sutural closure will lead to:
A
Compensatory growth of the other patent (open) sutures
25
What are the 6 synchondroses joints in the cranial base?
1. Spheno-ethmoidal (4 yrs)
2. Sphene-Occipital (12-14 years)
3. Spheno-petrosal (10-12)
4. Petro-occipitla (10-12)
5. Interoccipital (ant/post) 1-3 years
26
Describe the Frontal (metopic) suture
- Frontal and Frontal
| - Postnatal closure tiem is 2-4 years
27
Describe the Coronal suture:
- Frontal nad Parietal
| - Postnatal closure tiem is 40 years
28
Describe the sagittal suture:
Parietal and Parietal
29
Describe the lambdoid suture:
Parietal and and occipital
30
What is the Calvaria?
The calvaria is the top part of the skull. It is the upper part of the neurocranium and covers the cranial cavity containing the brain. It forms the main component of the skull roof. The calvaria is made up of the superior portions of the frontal bone, occipital bone, and parietal bones
31
Frontanelles are present in:
Calvaria
32
Failure to express signaling molecules alters sutural closure and will cause what two outcomes?
Sutures may fail to fuse
| Sutures may fuse prematurely
33
What is the Anterior fontanelle?
intersection b/w 2 frontal and 2 parietal
Adult structure: Bregma
Age postnatal closure: 9-18 mo
34
What is the Sphenoid fontanelle:
Intersection b/w sphenoid, temporal, frontal; parietal
Adult structure: Pterion
Age postnatal closure: 3-6 mo
35
What is the posterior fontanelle?
Intersection b/w 2 parietal and occipital
Adult structure: Lambda
Age postnatal closure: 3-6 mo
36
What is the Mastoid fontanelle:
Intersection b/w temporal, parietal, occipital
Adult structure: Astern
Age postnatal closure: 24 mo
37
What is the location of syndesmoses joints in facial skeleton?
1. Frontomaxillary
2. Frontozygomatic
3. Zygomaticotemporal
4. Zygomaticomaxillary
5. Pterygopalatine
6. Palatal
7. Nasofrontal
8. Internasal
9. Intermaxillary
38
What is displacement growth?
Movement of the whole bone either due to growth of the bone itself r growth of neighboring bone.
Growth of maxilla by displacement
39
What is primary displacement?
As bone enlarges due bone deposition, the bone moves to a new location
40
What is secondary displacement?
Enlargement of neighboring bones moves another bone to a new location
41
What is the outcome of primary and secondary displacement?
Downward and forward movement
42
Describe the growth of the Mandible:
Secondary growth cartilages: Condylar growth up' back and out; symphyseal allows for increased inter-condylar distance; angular carriages allows for increased length
Growth of alveolar process
Modeling/remodeling- deposition on posterior surface; resorption anterior
Displacement growth: growth of cranial base and condylar cartilage move mandible downward and forward
43
Describe the growth of the maxilla:
- Secondary growth cartilages: appositional
- Sutural growth: apposition growth
- Growth of maxillary sinus: Pneumatization
- Modeling/remodeling
- Displacement growth: Growth of maxilla and cranial base and growth of cartilaginous nasal capsule move the maxilla is downward and forward (inferior/anterior)
44
Viscerocranium (Facial skeleton) refers to:
Ectomesenchyme derived bones of jaw and neck. May be cartilaginous viscerocranium or membranous viscerocranium
45
What structures are from the Cartilaginous Viscerocranium?
- Incus
- Inferior conchae
- Malleus
- Stapes, Styloid process, lesser horn and body of hyoid
- Greater horn and body of hyoid
All are ectomesenchyme derived and will all undergo endochondral ossification
46
Meckel's Carilage is the cartilage precursors for:
What arch?
Malleus
Mandibular process of 1st PA
47
Richert's cartilage is the cartilaginous precursor for:
Arch?
Stapes, Styloid process, lesser horn and body of hyoid
2nd PA
48
The Palatopterygoquadrate is the cartilaginous precursor for:
Arch?
Incus
Maxillary process of 1st PA
49
Which structure from the Cartilaginous viscerocranium has no named precursor?
Incus: It is an outgrowth of the maxilla
50
Which structure from the cartilaginous viscerocranium is 3rd arch precursor from the 3rd PA
Greater horn and body of hyoid
51
What structures are considered Membraneous viscerocranium?
- Premaxilla
- Nasal bones
(medial nasal precursors)
- Maxilla
- Lacrimal
- Zygomatic bone (Zygoma)
- Palatine bone
- Squamous portion of temporal
-Vomer bones
- Body and ramps of mandible
All are Ectomesenchyme and go through intramembraneous ossification
52
What structures of the Membraneous viscerocranium are from the Maxillary 1st arch?
```
Maxilla
Lacrimal
Zygomatic bone
Palatine bone
Squamous portion of temporal
Vobmer bones
```
53
What structures of the membraneous viscerocranium are from the frontonasal process?
Premaxilla and Nasal bones
54
What structures of the membraneous viscerocranium are from the mandibular process of the 1st arch
Body and ramps of mandible
55
The condyle, coronoid, mental symphysis, articular eminent, malar region all develop from:
Secondary growth cartilages that became incorporated into the bone and either degenerated or underwent endochondral ossification
56
What is the Neurocranium?
- Includes cranial base and vault
- Functions to protect the brain and sensory organs
- Neurocranium derived from germ layers (GL): ectomesenchyme and paraxial mesoderm
- GL boundary is coronal and sphenoid-occipital sutures
57
What are the structures of the membraneous neurocranium?
Frontal bones
Parietal bones
Occipital (interparietal portion (unpaired))
All of the above form through intramembraneous ossification
58
What is the germ layer of the Frontal bones?
Ectomesenchyme
59
What is the germ layer of parietal bones?
Paraxial mesoderm
60
What is the germ layer of the occipital (interparietal portion)
paraxial mesoderm
61
What are the structures of the cartilaginous neurocranium?
- Ethmoid bone/perpendicular plate
- Sup/Middle conchae
- Body and wing of sphenoid
- Petrous portion of temporal bone
- Mastoid portion of temporal
- Base of occipital
Will all undergo endochondral ossification
62
Precondral cartilage and olfactory/nasal cartilaginous capsule will develop into:
Ethmoid/perpendicular plate sup. and middle conchae
63
Hypophyseal cartilage and pic capsule will develop into:
Body/wings of sphenoid
64
Parachordal cartilage and periodic capsule will develop into:
Petrous portion temporal mastoid of temporal bone and the base of the occipital
65
What cartilaginous precursors of the Cartilaginous neruocranium are Ectomesenchyme derived?
Prechordal
Hypophyseal
Olfactory/nasal
Optic
66
What cartilaginous precursors of the Cartilaginous neruocranium are paraxial derived?
Periotic
67
What cartilaginous precursors of the Cartilaginous neruocranium are P. Mesoderm derived?
Parachordal
68
What are the paired midline cartilages?
Prechordal
hypophyseal
Parachordal
69
What are the paired sensory capsules?
Olfactory/nasal
Optic
Periotic
70
Cartilage base develops by fusion of:
Sensory cartilage with midline cartilage; Will collectively undergo endochondral ossification
71
What are the 6 principal functions of oral mucosa?
1. Protection against mechanical forces
2. Physical barrier to microorganisms, toxins, antigens
3. Provide immunological defense via humoral and cell mediated immune responses
4. minor salivary glands prevent of desiccation and provided lubrication and buffering capacity
5. Innervation provides sensory and stereognostic input about environment (GSA and SVA)
6. Numerous sensory receptors: Nociceptors, Mechanoreceptors, chemoreceptors, thermoreceptors
72
What is a way to differentiate Nonkeratinized epithelium compared to others?
It has an intermedium layer (upper layer of spinous)
Histological appearance: Nuclei present/ cells frequently appear vaculated flattened cells
73
What is a way to differentiate the Parakeratinized epithelium compared to others?
It has a thin granulosum (1 layer)
Histological appearance: Pyknotic nuclei; flattened cells lighter color of superficial
74
What is a way to differentiate the (Ortho)keratinized epithelium compared to others:
Granulosum is 2-3 layers and has a corner (keratinized) layer
Histological appearance: No nuclei/keratin filaments
Color change of corneum
75
What are progenitor keratinocytes?
Found in basal layer: Stem cell capable of renewal/mitosis. It binds to basement membrane
76
What are maturing keratinocytes?
Found in all layers:
- Synthesize protein in keratohyaline granules
- synthesize intermediate filament (cytokeratin/ to no filaments) *** type may change in cancer
- Synthesize growth factors
77
What is the principal cell type associated with stratified squamous epithelium?
Keratoncytes
78
What are langerhans cells?
Found in spinous layer:
- APC
- Moves between the epithelium and local lymph nodes
- contact hypersensitivity
79
What are melanocytes?
Found in basal layer:
- Number of melanocytes same between individuals
- synthesize melanin as granules which are transferred to keratinocytes
- Number, size of melanin granules; turnover of pigment influences pigmentation
- Clinically: variable melanin pigment in palate; tongue, gingiva, buccal
80
What are Merkel cells?
Found in basal layer
| - Unencapsulated mechanoreceptors in epithelium: detects light/ fine touch; protects against excessive stretch
81
What two factors are involved in controlling epithelial phenotype and turnover rate?
1. Epithelial: Mesenchyme interactions: Underlying lamina propria (CT) determines the type of epithelium
2. Turnover rate: Turnover rate varies based on extend of keratinization. Drugs and inflammation affect turnover
82
What is Keratosis?
usually asymptomatic with the white color due to excess keratin production
83
What is Necrosis?
Usually painful, associated with trauma or infection. The white color is due to accumulation of dead cells, bacteria/ fungus
84
What may cause red lesions in the mouth?
- Loss of epithelium
- Loss of keratin associated with dysplasia
- Increase in vascularization and inflammation (erythematosis)
- Lesions may progress from to erosions of ulceration's
85
What are the characteristics of oral epithelium in the oral mucosa
- Stratified squamous epithelium
- Rete ridges: Epithelium projects into the underlying ct and aids in adhesion
- Dermal papilla: CT interdigitating with rate ridges
86
What are the characteristics of lamina propria in the oral mucosa
Underlying connective tissue finds BM to epithelium
- Contains: Ducts of salivary glands, sebaceous glands (possible), capillaries, lymphocytes, leukocytes
- Papillary layer: superficial layer of CT ( increase in LCT)
- Reticular layer: deeper layer of CT (increase in DICT)
87
What are the characteristics of the submucosa in the oral mucosa?
May be LCT with higher amounts of adipose tissue, or more DICT, with less adipose
- Salivary glands, larger blood vessels are present
88
What is lining mucosa?
Usually associated with SSNK epithelium
Shallow rete ridges
Submucosa is usually present
Soft pliable
Located: Labial surface of lip, buccal surface of cheek, alveolar mucosa, soft palate, floor of mouth, ventral tongue
89
What is Masticatory mucosa?
Usually parakeratinized or SSK epithelium
Long rete ridges
Submucosa is variable: mucoperiosteum often present
Firm and immobile
Located: Hard palate, attached gingiva; found in regions for compression or shearing forces
90
What is specialized mucosa?
- Associated with SSK and lingual papilla containing taste buds
- Also associated with the vermillion zone of lip (no taste buds)
- Longe Rete ridges
- Submucosa is not distinct, CT of mucosa binds to mucosa
Located: predominately anterior 2/3 dorsal surface of tongue- Vermillion zone of lip
91
What is the Outer Cutaneous region of the lip?
It has similar characteristics to thin skin
- Thin SSK epithelium
- Hair follicles
- Sweat glands
- Sebaceous glands
Vermillion border is the mucocutaneoux junction: is a term used to refer to the transition from skin to mucous membrane
92
What is the Vermillion Zone (red area)?
A transition zone is located in the area between the dry skin and wet mucosa membranes.
- Thick SSK epithelium
- Salivary and sebaceous glands are absent
- Increased number of sensory receptors in CT: Meissner's corpuscles are present
- Highly vascularized CT- Cause region to appear red
93
What is the Intermediate zone?
Transition between vermillion zone and labial mucosa
| - Associated with transition of parakeratinized - nonkeratinized epithelium
94
What is the Inner mucosal region: AKA labial surface?
- Thick SSNK epithelium
- Well vascularized
- Minor seromucous (mixed) glands, adipose issue in LP/submucosa
95
What are the histological features of the cheek: (Buccal surface)
Similar to inner mucosal surface of lip
- thick SSNK epithelium
- Well vascularized
- minor seromucous (mixed) glands, adipose tissue in LP/submucosa
96
What is Fordyce's spot?
Aberrant sebaceous glands which lack hair follicles and open directly onto the epithelial surface may be found on the vermillion and labial mucosa, buccal mucosa or angle of the mouth
97
The hard palate is:
The anterior 2/3 and comprised of bone
98
The soft palate is:
Posterior 1/3 and comprised of fibro-muscular tissue attached to posterior edge of hard palate
99
What type of epithelium covers the nasal side?
PSCC
100
What type of epithelium covers the Oral side?
Covered with oral ss epithelium (extend of keratinization depends on location)
101
What are the general features of the hard palate (Oral side)?
- Covered with masticatory mucosa
- Thick SSK -> Parakeratinized epithelium
- Long rete ridges
- Submucosa varies based on region
102
What are the Characteristics of the Midline region?
- SSK epithelium
- Deep rete ridges
- Mucoperiosteum is visible
103
What are characteristics of the Anterolateral region (Fatty zone)
- Epithelium is folded into rug
- epithelium SSK -> Parakeratinized
- Deep rete ridges interdigitate with underlying CT papillae
- CT contains blood vessels and nerves
- Submucosa contains adipose and attached to bone
104
What are characteristics of the Posterolateral region (Glandular zone)?
```
Parakeratinized -> SSNK
Masticatory mucosa present
Submucosa contains mucous glnads
Bone present
Rete ridges become flattened
```
105
What are the general characteristics of the soft palate (oral side)?
- Covered with lining mucosa
- Thick SSNK epithelium
- Shallow rete ridges interdigitating with underlying CT tissue
- Submucosa is loose
- Mucosa gland present
- Skeletal muscle present
- Bone is absent
106
What are the key features of the minor salivary glands?
- Unencapsulated groups of secretory units
- Intra-oral location (submucosa)
- Short; multiple excretory ducts-few interlobular ducts
- epithelium or skeletal muscle may be in field of veiw
107
What are the key features of major salivary glands?
- Encapsulated by CT- Divided into lobules
- Extra-oral location (bilateral)
- Numberous intra and interlobular ducts
- long excretory ducts which open into oral cavity
108
Salivary glands can be classified based on:
Size, Location, amount of saliva produced and type of secretion
109
What type of secretion do salivary glands produce?
Merocrine
110
Constitutive exocytosis occurs in:
Minor glands
111
What is regulated exocytosis?
Controlled by ANS
- All major glands
ANS modulates flow in mino
- Both parasympathetic and sympathetic of ANS contribute; parasympathetic caused a greater volume response; sympathetic greater protein response than volume
112
Salivary secretion depends on:
Reflex activity. Neuronal reflexes control secretions
113
What is an unconditional reflex?
Tactile or gustatory (taste) input stimulates secretion; present at birth
114
What is a Gustatory Salivary reflex?
stimulation of taste buds; sour highest
115
What is a masticatory salivary reflex?
Stimulation of chewing from PDL and mucosa
116
what is an olfactory salivary reflex?
Stimulates submandibular and sublingual
117
what is a conditioned reflex?
acquired response due to stimulation through special senses; requires processing through her brain centers and may stimulate or inhibit salivation
118
Name the germ layer, epithelium, location and type of secretion for the labial gland:
Germ layer: Ectoderm
Epithelium: SSNK
Location: Submucosa of lip (inner mucosal surface)
Secretion: Mixed
119
Name the germ layer, epithelium, location and type of secretion for the Buccal gland:
Germ layer: Ectoderm
Epithelium: SSNK
Location: Submucosa of cheek
Secretion: mixed
120
Name the germ layer, epithelium, location and type of secretion for the Palatine gland:
Germ layer: Ectoderm
Epithelium: SSPK; SSNK
Location: Submucosa of posterior-lateral of hard palate; Submucosa soft palate
Secretion: Pure mucous
121
Name the germ layer, epithelium, location and type of secretion for the Lingual gland:
Germ layer: Endoderm; Ectoderm
Epithelium: SSK; SSNK
Location:
- 1. ANTERIOR: tip of tongue- duct opens ventral surface
- 2. MIDDLE: anterolateral to sulcus terminalis (circumvallate/foliate papilla)- Ectoderm
- 3. POSTERIOR: posterior 1/3 tongue with lingual tonsils - Endoderm
Secretion: 1. Mixed, 2. Pure serous (glands of von ebner) 3. Pure mucous
122
Minor glands contribute to what percentage of total salivary secretion?
5-10%
123
What percentage of the saliva secreted from minor glands is mucous?
70%
124
How many groups of minor salivary glands are located in submucosa layer of oral mucosa/ associated structures?
600-1000
125
Name the germ layer, epithelium, location and type of secretion for the Parotid gland:
```
Location: Anterior to ear
Size: Largest
Type of secretion: Pure serous
Amount secreted: 25-60 %
Germ layer: Ectoderm
```
126
Name the germ layer, epithelium, location and type of secretion for the Submandibular Gland
```
Location: Angle of the mandible
Size: Intermediate
Type of secretion: mixed >60% serous
Amount secreted: 60-25%
Germ layer: Endoderm
```
127
Name the germ layer, epithelium, location and type of secretion for the Sublingual gland:
```
Location: Anterior floor of mouth
Size: Smallest
Type of secretion: Mixed > 70% mucous
Amount secreted: 5-8%
Germ layer: Endoderm
```
128
Major glands produce what percentage of total saliva?
90%
129
During stimulation which gland produces more saliva? The Parotid or the submandibular?
Parotid
130
Which major glands secretory activity are mainly regulated by exocytosis with some constitutive?
Parotid and Submandibular
131
The activity of the sublingual is regulated via:
constitutive exocytosis
132
What are the two structural components of the salivary glands?
1. Supprotive (stromal) tissue: Connective tissue
2. Glandular (parenchymal) tissue:
- myoepithelial cells
- secretory acing cells (from acing units- clusters of secretory cells)
- Dust cells
133
Describe the Stromal support in salivary glands:
Connective tissue:
- CT in major glands forms a capsule that divides tissue into lobes
- CT supports the glandular epithelium
- Conveys blod vessels and nerves
- contains: lymphocytes, macrophages, fibroblasts, plasma cells
134
What cell synthesizes and secretes IgA?
Plasma cells
135
What is palatal adenoma:
Non-ulcerated swelling
136
What is adenoma?
A benign glandular tumor developing form cells of epithelial original and may affect major or minor salivary glands. 80% occur within the parotid gland and 10-20% occurring in minor gland with palatal glands most prevalent
137
What is Carcinoma?
Any malignant form of cancer affecting cells of epithelial origin
138
What is Adenocarcinomas?
Refers to tumors that develop in silvery glands. These usually appear red and ulcerated over time
139
What are the outcomes from radiation treatment?
- Radiation caries: A rapidly developing and highly destructive form of tooth decay, is a well known dental consequence of radiotherapy of malignant tumors in the head and neck region
- Radiation caries appears along the gingival margin and can weaken the tooth surface
- Hypo-Salivation is induced due to scarring of gland/duct and loss of acing cells
140
What are myoepithelial cells?
AKA Basket cells-- (Part of Parenchymal tissue)
Have connective activity
Location: b/w acing cells and basement membrane
Function: Supportive; facilities secretory discharge of secretory acing cells
Under control of ANS
141
What are secretory (Acing) cells:
Serous, Mucous, and mixed cells
142
what cells synthesize glycoproteins and enzymes?
| These cells have enzyme rich watery secretion which aids in digestion
Serous cells
143
What cells synthesize mucin (mucopolysaccharides)? These cells have carbohydrate rich viscous secretion which aids in protection/bolus formation?
Mucous cells
144
What is the function of salivary ducts?
Involved in transport and modification of saliva secreted from acing cells
145
Where can a mean excretory duct be found and what is the related name? What does it do?
Open into the oral cavity;
- Parotid = stenson's duct
- Submandibular = warton's duct
- sublingual = Bartholin's duct
Note: Epithelium is stratified squamous to stratified columnar/cuboidal
146
What are interlobular ducts?
Excretory ducts found in CT between the lobules
Epithelium is stratified cuboidal to pseudo-stratified columnar to simple columnar
147
What are interlobular ducts?
Two types of ducts found in the lobule surround by acinar cells:
1. Striated ducts: receives product from intercalated duct:
- modifies ion concentration of saliva
- epithelium is simple columnar to cuboidal
2. Intercalated duct: Receives secretory products directly from the acing cells; limited modifications of saliva
- epithelium: is low/flattened cuboidal
148
What secretes lysozyme and lactoferrin?
Intercalated ducts
149
What is the longest intercalated duct?
Longest is in parotid gland
150
What is involved in a active transport; reabsorption and secretion of electrolytes but no water?
Striated ducts
151
Where can the longest striated duct be found?
Submandibular
152
What is a mucocele?
small soft lesions involving the retention of seromucous secretions in the subepithelial CT due to trauma to minor salivary glands
Cause: Damage to the ducts of the minor salivary glands may result in saliva becoming trapped in the surrounding CT
153
What is a Ranula?
A mucocele involving the major salivary glands on the floor of the mouth
Cause: Tramua to a majro excretory duct leads to pooling of saliva within the submucosa CT layer of tissue- Most rankle involve the major excretory ducts of the sublingual or submandibular gland
154
What are the biochemical components of saliva?
- Water
- Electrolytes
- Mucopolysacharides (mucin)
- Salivary proteins (Lacotferrin, cystain, Histatins, acidic proline- rich proteins)
- Enzymes (amylase, lipase, lysosome)
- Antibodies (secrete IgA)
- Other components include: insulin serum albumin, epidermal growth factors
- small organic molecules: Glucose, amino acids, urea, and cholesterol
155
What are the cellular components of saliva?
Desquamated epithelial cells
Lymphocytes
Bacteria
156
Whole saliva includes both:
biochemical and cellular components that are secreted from all glands
157
What is Primary saliva?
Biochemical components secreted from acing cell/intercalated duct
158
IN Unstimulated/resting flow:
There will be higher amounts of mucous; role of saliva is protection of tooth and mucosa via pellicle
159
IN Stimulated flow:
There will be a higher amount of enzymes, fluids and electrolytes : Role of saliva is clearance; buffering; remineralization
160
Which active components function is protection and are involved in the clearance of tooth surface, lubrication, and pellicle formation?
Water
Mucin
Salivary proteins
161
Which active comments function in buffering capacity and are involved in pH maintenance and neutralization of acids?
PO43-, HCO3-
162
What active components are involved in tooth integrity and help with enamel mineralization/maintenance and will inhibit calcium-phosphate precipitation
Ca2+, PO43-, Fl-, and salivary proteins
163
What active components function in antimicrobial activity and create a physical barrier, involved in immune surveillance, and are bactericidal
Mucins, sIgA, and lysozyme, lactoferrin
164
What active components are involved in digestion and taste and function in bolus formation and carbohydrate and triglyceride digestion?
Water, Amylase, lipase
165
Which active components are involved in tissue repair and are involved in wound healing/ epithelial repair?
Growth factors
166
Primary saliva production is produced by:
Secretory acing cells of gland:
- Composition: Enzymes, proteins, antibodies, water, electrolytes
- Tonicity is isotonic
167
Ionic modification of the primary saliva is modified by:
Started duct cells and interlobular duct cells.
Mechanism: Ion transport via channels and pumps; no change in water
Result: Tonicity of saliva is hypotonic
168
T/F: Tonicity and ion concentration and pH are alters with change in flow rate
True
169
Immune-Protective modification of primary saliva is modified by:
Acing cells and intercalated ducts modify saliva by transport and secretion of sIgA antibodies into saliva
Mechanism: IgA transported from Ct into acing and duct cells and converted to a secretory form of IgA
Outcome: addition of sIgA of primary saliva provides mucosal defense
170
What are the steps of immune-protective modification of primary saliva?
1. Plasma (B) cells synthesis Ina
2. Binding of secretory IgA to receptor on acing/duct cells
3. Receptor mediated endocytosis transports sIgA into acing cell
4. Transcytosis of secretory component of IgA through cell
5. Constitutive exocytosis into saliva: Immuno-protection occurs continually including during unstimulated conditions
171
Describe the Neural pathway for the Parotid
CN IX
Inferior salivary nucleus -> Preganglionic fibers of lesser petrosal (IX) -> Otic ganglion -> Post ganglionic fibers travel with the auriculotemporal of V3 -> Target tissue
(similar pathway for minor glands: (post ganglionic travel with different branches than V3 auriculotemporal) Bccal (Via V3), lingual post 1/3; anterior to sulcus terminals; and oropharynx (Via br. of IX)
172
Describe the neuronal pathway for minor glands: Palatal
Superior salivary nucleus -> preganglionic fibers of greater petrosal (VII) -> pyterygopalatine ganglion postganglionic fibers travel with greater palatine of V
173
What is the Mechanism of control of salivary gland secretion by ANS?
Salivary target issue of ANS = parasympathetic and sympathetic act cooperatively on acing cell; ducts; and myopeitheial cells.
Outcome: ANS stimulation causes regulated exocytosis of secretory granules from acing cells
Fluid/electrolyte secretion - open water channels and facilitate electrolyte transport in acing cells
Increased flow rate - (stimulated flow)- increased electrolyte transport in striated ducts -> buffering capacity and tonicity
174
What are 4 factors that can affect rate of flow?
Blood loss, Dehydration, drugs, stress
175
What neurotransmitter is released from postganglionic fibers in Parasympathetic?
Acetylcholine
176
What is the principal role of the Parasympathetic system?
Regulates opening of water and ion channels; some exocytosis acinar proteins
177
What is the receptor that binds acetylcholine?
Muscarinic
* Most fluid secretion of glands is due to muscarinic stimulation
178
What neurotransmitter released from postgangionic fibers in sympathetic?
Norepinephrine
179
What is the principal role of the Sympathetic system?
Regulates exocytosis of acing proteins
180
What is the receptor that binds Norepinephrine?
1. B-adrenergic: Most protein secretion due to B-adrenic stimulation
2. A-adrenergic: may modulate activation of water channels
181
Norepinephrine and acetylcholine of ANS binding to receptors on the acing cell lead to:
Increased flow rate via increased release of fluid and electrolytes
182
T/F: Water channels are present in duct cells but not acinar cells.
False:
Water channels are present in acinar cells but not in duct cells
183
What kind of solution is primary saliva when released from acing cells?
Isotonic: Will be further modified in ducts via electrolyte transport
184
Describe saliva in a resting flow rate:
Primary Saliva: Rich in proteins; electrolytes (NA+, Cl-, K+, HCO3-) and water: Isotonic
- Modified as saliva flows through duct:
- Removal of Na+/Cl (high absorption) * Na-cl absorption greater than HCO3 secretion
- Secretion HC03- (some secretion)
- no water absorbed in duct
Slower flow rate: More time to reabsorb
Result: Hypotonic saliva (relative to plasma)
Resting pH: 6.3-6.7
185
What is the outcome of ANS stimulation saliva composition:
Increased secretion and flow rate
- Parasympathetic: Produces thin watery; low viscosity solution
- Sympathetic: produces viscous enzyme rich; low fluid solution
186
Describe primary saliva in stimulated conditions
Increases in electrolytes and water; proteins
- Modified in duct by:
- Removal of Na/Cl- (little absorption)
- Secretion of HCO3 (Higher rate when stimulated via ANS)
- No water removed in duct
Increased Flow rates: High flow rate = less time to reabsorb
Result: Isotonic saliva (relative to plasma)
Stimulated pH is: ????
187
What is hyposalivation:
Decrease in volume/rate of salivary secretion disease, nerve damage, pharmacology, physiology reasons
188
What are sialadentitis?
Clinical term for a group of inflammatory disorders affecting the salivary glands:
- inflammation may result from, obstruction, trauma, bacterial or viral infections are the most common conditions that affects salivary glands and ducts
189
What is Sialolithiasis:
Clinical term for the condition of salivary duct store (sialolith)
Formation- Calcification of salivary proteins which block the excretory duct
190
What is Sjogren syndrome:
autoimmune disorders affects lacrimal, and salivary glands
Pharmacological induced: Anticholinergics leads to decreased salivation
191
Hypersalivation:
increase in volume/reate of salivary secretion due to neurological disease, stroke, inflammation, pharmacology, psychological reasons
192
What is Sialorrhea:
Hypersalivation: associated with drooling
193
What are the outcomes of Xerostomia?
- Buring sensation or oral soreness
- Taste impairment or dysgeusia
- Loss/atrophy of papillae (dorm of tongue appear fissured)
- An increased rate of smooth surface dental caries (primarily affecting cervical regions of mandibular incisors)
- Plaque and debris retention in the mouth, leading to poor oral hygiene and halitosis
- Gingival recession with an increased susceptibility to periodontal disease and tooth loss
- difficulty retaining dentures in mouth
- Recurrent infections of the major salivary glands
- Increased risk of recurrent oral infections especially oral candidiasis and angular cheilitisi
- Difficulty swallowing
- Dry cough
- Hoarse voice
