Ora Mucosa Flashcards
1
Q
What does the clinical appearance of oral mucosa reflect?
A
It reflects the underlying histology, both in health and disease.
2
Q
How is the oral cavity often described?
A
It is described as a mirror that reflects the health of the individual.
3
Q
What changes can indicate disease in the oral mucosa?
A
Alterations in the oral mucosa lining the mouth can indicate systemic conditions.
4
Q
What are some systemic conditions that may be revealed by changes in the oral mucosa?
A
Examples include diabetes, vitamin deficiencies, and the local effects of chronic tobacco or alcohol use.
5
Q
What type of tissue almost continuously lines the oral cavity?
A
The oral mucosa almost continuously lines the oral cavity.
6
Q
What is the microscopic composition of the oral mucosa?
A
It is composed of stratified squamous epithelium overlying connective tissue proper, or lamina propria, with possibly a deeper submucosa.
7
Q
What lies between the epithelium and connective tissue in the oral mucosa?
A
A basement membrane lies between the epithelium and connective tissue.
8
Q
Does the basement membrane separate the epithelium and connective tissue?
A
No, it serves as a continuous structure linking the two.
9
Q
What are the three main types of oral mucosa found in the oral cavity?
A
The three main types are masticatory mucosa, lining mucosa, and specialized mucosa.
10
Q
Where is masticatory mucosa found, and what are its features?
A
Masticatory mucosa is found on the hard palate, attached gingiva, and dorsum of the tongue. It has keratinized epithelium and a dense lamina propria.
11
Q
What is the clinical appearance and function of lining mucosa?
A
Lining mucosa has a softer, moister surface that can stretch and compress, acting as a cushion. It includes the buccal mucosa, labial mucosa, alveolar mucosa, and the mucosa lining the floor of the mouth, soft palate, and ventral surface of the tongue.
12
Q
What type of epithelium does lining mucosa have?
A
Lining mucosa has nonkeratinized stratified squamous epithelium.
13
Q
What is the function of specialized mucosa in the oral cavity?
A
Specialized mucosa, found in the taste buds on the tongue’s lingual papillae, allows for the perception of taste and includes nerve endings for pain, touch, and temperature.
14
Q
What are the regional differences in the oral mucosa based on?
A
Regional differences are based on specific histologic features in different regions of the oral cavity.
15
Q
What do the histologic features of oral mucosa explain?
A
They explain the differences observed clinically when examining these regions.
16
Q
What are the three types of stratified squamous epithelium found within the oral cavity?
A
The three types are nonkeratinized, keratinized, and parakeratinized epithelium.
17
Q
What is keratin, and what are its properties?
A
Keratin is a tough, fibrous, opaque, waterproof protein that is impervious to pathogenic invasion and resistant to friction.
18
Q
Where is keratin produced in the oral mucosa?
A
It is produced during the maturation of keratinocyte epithelial cells as they migrate from the basement membrane to the surface of keratinized tissue.
19
Q
In which regions of the oral cavity is keratinized tissue found?
A
Keratinized tissue is found in certain regions of the oral mucosa within the oral cavity.
20
Q
What are the characteristics of lining mucosa?
A
Lining mucosa has a softer surface texture, a moist surface, and can stretch and compress, acting as a cushion for underlying structures.
21
Q
Which areas of the oral cavity are covered by lining mucosa?
A
Lining mucosa includes the buccal mucosa, labial mucosa, alveolar mucosa, mucosa lining the ventral surface of the tongue, the floor of the mouth, and the soft palate.
22
Q
What type of epithelium is associated with lining mucosa?
A
Lining mucosa is associated with nonkeratinized stratified squamous epithelium.
23
Q
How does the interface between the epithelium and lamina propria in lining mucosa compare to that of masticatory mucosa?
A
The interface in lining mucosa is generally smoother with fewer and less pronounced rete ridges and connective tissue papillae compared to masticatory mucosa.
24
Q
What provides lining mucosa with its movable base or rather what make it be able to stretch and move?
A
The presence of elastic fibers in the lamina propria provides the tissue with a movable base.
25
What is located deep to the lamina propria in lining mucosa?
A submucosa is usually present deep to the lamina propria in lining mucosa.
26
What does the submucosa in lining mucosa overlie, and what does it allow?
It overlies muscle and allows for compression of the superficial tissue.
27
Why does lining mucosa serve well in regions where a movable base is needed?
It is suitable for regions like during speech, mastication, and swallowing due to its compressibility and mobility.
28
Why do surgical incisions in lining mucosa frequently require sutures?
Tissue movement in this area often necessitates sutures for closure.
29
How does the permeability of lining mucosa affect dental medications?
Lining mucosa is the most permeable to liquids, making it easier for dental medications to be absorbed.
30
How many layers are found within the epithelium of lining mucosa?
Each tissue type of lining mucosa has at least three layers within the epithelium.
31
What is the basal layer in lining mucosa, and where is it located?
The basal layer, or stratum basale, is the deepest of the three layers and consists of a single layer of cuboidal epithelial cells overlying the basement membrane.
32
What is the function of the basal layer in lining mucosa?
It is germinative, as mitosis of epithelial cells occurs within this layer.
33
What does the basal layer produce?
It produces the basal lamina of the basement membrane.
34
What is the intermediate layer in nonkeratinized epithelium, and where is it located?
The intermediate layer, or stratum intermedium, is located superficial to the basal layer in nonkeratinized epithelium.
35
What is the structure of the cells in the intermediate layer?
The cells are larger, stacked, and polyhedral-shaped, appearing plumper due to larger amounts of fluid in their cytoplasm.
36
Do cells in the intermediate layer retain the ability to undergo mitosis?
No, the cells in this layer have lost the ability to undergo mitosis.
37
the intermediate layer of lining epithelium makes up how much of nonkeratinized epithelium?
It makes up the bulk of nonkeratinized epithelium.
38
What is the superficial layer in nonkeratinized epithelium called, and where is it located?
It is called the stratum superficiale and is located at the most superficial level in nonkeratinized epithelium.
39
What is the structure of cells in the superficial layer?
The cells are larger, stacked, polyhedral epithelial cells, with the outermost cells flattening into squames.
40
What happens to the cells in the superficial layer as they age and die?
The squames in the superficial layer shed or are lost during tissue turnover.
41
How does maturation in nonkeratinized tissue compare to keratinized tissue?
Maturation in nonkeratinized tissue occurs at a lesser level than in keratinized tissue.
42
What do the labial mucosa and buccal mucosa line?
They line the inner lips and cheeks.
43
What is the clinical appearance of labial and buccal mucosa?
They appear as opaque pink, shiny, moist, compressible tissue that stretches easily, with possible areas of melanin pigmentation.
44
How are labial and buccal mucosa classified?
They are classified as lining mucosa.
45
What are the histologic features of the labial and buccal mucosa?
They have extremely thick nonkeratinized epithelium overlying a lamina propria with extensive vascular supply, giving an opaque pink appearance.
46
What components in the lamina propria of labial and buccal mucosa allow for stretch and shape retention?
Elastic fibers and collagen fibers in the lamina propria give the tissue the ability to stretch and return to its original shape.
47
What is the role of the submucosa in labial and buccal mucosa?
The submucosa contains adipose connective tissue and minor salivary glands, contributing to compressibility and moisture, and is firmly attached to underlying muscle to prevent interference during mastication or speech.
48
What are Fordyce spots, and where are they located?
Fordyce spots (or granules) are small, yellowish bumps scattered throughout the tissue of the labial and buccal mucosa.
49
Are Fordyce spots harmful?
No, they are harmless and present in most of the population.
50
In which age group are Fordyce spots more prominent?
They are more prominent in older individuals than in children or young adults.
51
Fordyce spots correspond to …..
They correspond to deposits of sebum from misplaced sebaceous glands in the submucosa.
52
What is the usual characteristic of nonkeratinized epithelium compared to keratinized epithelium?
Nonkeratinized epithelium usually lacks superficial layers showing keratinization.
53
What is hyperkeratinization, and what causes it in nonkeratinized epithelium?
Hyperkeratinization occurs when nonkeratinized epithelium transforms into keratinized epithelium in response to frictional or chemical trauma.
54
What oral habits can lead to hyperkeratinization of the buccal mucosa?
Habits such as clenching or grinding (bruxism) can lead to hyperkeratinization.
55
What is linea alba, and where does it form?
Linea alba is a white ridge of calloused tissue that forms horizontally at the level where maxillary and mandibular teeth come together and occlude.
56
What is the clinical appearance of alveolar mucosa?
It is a reddish-pink tissue with blue vascular areas, shiny, moist, compressible, and extremely mobile.
57
How is alveolar mucosa classified?
It is classified as lining mucosa.
58
What type of epithelium does alveolar mucosa have?
It has an extremely thin nonkeratinized epithelium.
59
Why does alveolar mucosa appear redder than labial or buccal mucosa?
The thin epithelium overlies but does not obscure an extensive vascular supply in the lamina propria.
60
What provides the mobility of alveolar mucosa?
The presence of numerous elastic fibers in the lamina propria and the loosely attached submucosa provide mobility.
61
What components are found in the submucosa of alveolar mucosa?
The submucosa contains minor salivary glands and numerous elastic fibers in loose connective tissue, allowing for moisture and increased mobility.
62
What is the clinical appearance of the ventral surface of the tongue and the floor of the mouth?
Both appear as reddish-pink tissue with blue vascular areas, shiny, moist, and compressible.
63
How does the mobility of the floor of the mouth compare to the ventral surface of the tongue?
The floor of the mouth has some mobility, while the ventral surface of the tongue is firmly attached yet allows some stretching along with tongue muscles.
64
How is the ventral surface of the tongue and the floor of the mouth classified?
They are classified as lining mucosa.
65
What is the lingual frenum, and where is it located?
The lingual frenum is a midline fold of tissue connecting the ventral surface of the tongue to the floor of the mouth.
66
What are sublingual folds, and where are they located?
The sublingual folds are ridges of tissue on each side of the floor of the mouth, extending from the lingual frenum to the base of the tongue.
67
What type of epithelium is present in the ventral surfaces of the tongue and floor of mouth regions?
Both regions have an extremely thin nonkeratinized epithelium overlying a lamina propria with an extensive vascular supply.
68
Why do the ventral surface of the tongue and floor of the mouth tissue appear redder and show veins more prominently?
The thin epithelium does not obscure the extensive vascular supply, making veins such as the deep lingual veins more apparent.
69
What are the histologic features of the ventral surface of the tongue?
The connective tissue papillae of the lamina propria are numerous, with some elastic fibers and a few minor salivary glands providing stretch and moisture.
70
How is the submucosa associated with the ventral surface of the tongue?
It is extremely thin and firmly attached to the underlying tongue muscle.
71
How does the attachment of the mucosa and muscle affect function?
The mucosa and muscles function as one unit, reducing movability during mastication and speech.
72
What are the histologic features of the floor of the mouth?
The connective tissue papillae of the lamina propria are broad, and the submucosa contains loose connective tissue with adipose tissue and includes the submandibular and sublingual salivary glands.
73
What gives the floor of the mouth its compressibility and moisture?
The adipose connective tissue provides compressibility, while the submandibular and sublingual salivary glands provide moisture.
74
How is the submucosa attached in the floor of the mouth?
It is loosely attached to the underlying bone and muscles, allowing movability when the tongue moves during mastication and speech.
75
What are mandibular tori, and where do they develop?
Mandibular tori are bony growths that develop on the lingual aspect of the mandible.
76
Are mandibular tori usually benign or malignant?
They are usually benign and painless.
77
When do mandibular tori typically become noticeable?
They often go unnoticed unless they become large enough to cause discomfort or complications.
78
Where are mandibular tori usually located?
They are usually present bilaterally in the area of the premolars.
79
What shapes can mandibular tori take?
They can appear lobulated, nodular, or even fused together.
80
What covers mandibular tori, and do they vary in size?
They are covered by oral tissue and can vary in size.
81
What is the clinical appearance of the soft palate?
The posterior part of the palate appears as deep pink with a yellowish hue, has a moist surface, and is compressible and elastic.
82
How is the soft palate classified?
It is classified as lining mucosa.
83
What type of epithelium does the soft palate have?
It has a thin nonkeratinized epithelium overlying a thick lamina propria.
84
What features of the lamina propria contribute to the soft palate’s mobility?
The lamina propria has numerous connective tissue papillae and a distinct elastic layer with elastic fibers.
85
How is the submucosa of the soft palate attached, and what does this enable?
The submucosa is extremely thin and firmly attached to the underlying muscle, allowing for speech and swallowing.
86
What components of the submucosa give the soft palate its characteristic appearance and properties?
The submucosa contains adipose connective tissue (giving a yellow hue and compressibility) and minor salivary glands (providing moisture).
87
What is the clinical appearance of masticatory mucosa?
It has a rubbery surface texture and resiliency.
88
Where is masticatory mucosa found?
It is found in the mucosa of the hard palate, the attached gingiva, and the dorsal surface of the tongue.
89
What types of epithelium are associated with masticatory mucosa?
It is associated with orthokeratinized and parakeratinized stratified squamous epithelium.
90
How does the interface between epithelium and lamina propria differ in masticatory mucosa compared to lining mucosa?
The interface is highly interdigitated with numerous and more pronounced rete ridges and connective tissue papillae, giving it a firm base.
91
Is the submucosa present in masticatory mucosa, and what is its role?
The submucosa is either an extremely thin layer or absent, and when it overlies bone, it increases tissue firmness.
92
What features allow masticatory mucosa to function in regions that require a firm base?
Its histologic features, including keratinization and interdigitated interface, make it suitable for regions needing firmness during mastication and speech.
93
What distinguishes orthokeratinized stratified squamous epithelium from nonkeratinized tissue?
Orthokeratinized epithelium demonstrates keratinization of epithelial cells throughout its most superficial layers.
94
Where is orthokeratinized stratified squamous epithelium commonly found?
It is found in the masticatory mucosa of the hard palate and attached gingiva, and in the specialized mucosa of the lingual papillae on the dorsal surface of the tongue.
95
What happens to epithelial cells as orthokeratinized tissue matures?
Cells form keratin within the superficial layers, creating visible and physiologic differences as they migrate superficially.
96
How does orthokeratinized epithelium differ in layering compared to nonkeratinized epithelium?
Orthokeratinized epithelium has more layers superficial to the basal layer, with four distinct layers.
97
What is the basal layer in orthokeratinized epithelium called, and what is its function?
The basal layer, or stratum basale, is responsible for mitosis and produces the basal lamina of the basement membrane.
98
What are the two sub-layers of the basal lamina in the basement membrane?
The lamina lucida (a clear layer closer to the epithelium) and the lamina densa (a dense layer closer to the connective tissue).
99
What is the function of the basal layer in epithelial tissue?
It generates new cells through mitosis and helps maintain the structural integrity of the basement membrane.
100
What is the prickle layer in orthokeratinized epithelium, and where is it located?
The prickle layer, or stratum spinosum, is located superficial to the basal layer.
101
What happens to cells as they migrate to the prickle layer?
The cells lose the ability to undergo mitosis, which they had in the basal layer.
102
What is the primary function of the prickle layer in orthokeratinized epithelium?
It makes up the bulk of the orthokeratinized epithelium, providing structure and support.
103
What is the granular layer in orthokeratinized epithelium called, and where is it located?
The granular layer, or stratum granulosum, is located superficial to the prickle layer.
104
What is the structure of the epithelial cells in the granular layer?
The cells are flat and stacked in a layer that is three to five cells thick.
105
What is the most superficial layer in orthokeratinized epithelium?
It is the keratin layer, or stratum corneum.
106
How does the thickness of the keratin layer vary in the oral cavity?
The thickness varies depending on the region of the oral cavity.
107
What is the structure of cells in the keratin layer?
The cells are flat, have no nuclei, and their cytoplasm is filled with keratin.
108
What does the keratin in the keratin layer consist of?
It consists of a complex of keratohyaline granules and intermediate filaments, forming a dense, opaque material.
109
What happens to the outer cells (squames) in the keratin layer?
The squames flatten, shed, or are lost as part of tissue turnover because they are no longer viable.
110
What role do the squames and keratin material play in the epithelium?
They form a major part of the epithelial barrier and are continuously renewed as cells mature from deeper layers.
111
What is the clinical appearance of the hard palate?
The anterior part appears as whiter pink tissue that is immobile and firm, with a cushioned feeling in the posterior lateral zones and a firmer feeling in the medial zone.
112
What structures on the hard palate are firm to the touch?
The palatine rugae and the median palatine raphe are firm to the touch.
113
How is the hard palate classified?
It is classified as masticatory mucosa.
114
What type of epithelium is present in the hard palate? How thick is the lamina propria?
It has a thick layer of orthokeratinized epithelium overlying a thick lamina propria.
115
Where is submucosa present in the hard palate, and what is its function?
Submucosa is present only in the lateral zones, providing a cushioned feeling when palpated, and it overlies the bones of the palate.
116
What does the submucosa in the anterior part of the lateral zone of the hard palate contain?
It contains adipose connective tissue.
117
What does the submucosa in the posterior part of the lateral zone of the hard palate contain?
It contains minor salivary glands.
118
Is the submucosa present in the medial zone of the hard palate?
No, the submucosa is absent in the medial zone.
119
How does the absence of submucosa affect the medial zone of the hard palate?
It gives the tissue a firmer feeling when palpated.
120
What are palatal tori, and where are they located?
Palatal tori are bony growths that develop on the midline of the hard palate.
121
Are palatal tori usually benign or malignant?
They are usually benign and painless.
122
How do palatal tori typically appear?
They can appear lobulated or nodular and are covered in oral tissue.
123
What type of epithelium is associated with the masticatory mucosa of the attached gingiva?
Parakeratinized stratified squamous epithelium.
124
Where are higher levels of parakeratinized epithelium found compared to orthokeratinized epithelium?
In the attached gingiva.
125
What is the relationship between parakeratinized epithelium and lingual papillae?
It is associated with the specialized mucosa of the lingual papillae on the dorsal surface of the tongue.
126
What are the layers present in parakeratinized epithelium?
It may have all the same layers as orthokeratinized epithelium (basal layer, prickle layer, granular layer, and keratin layer), but the granular layer may be indistinct or absent.
127
How does the keratin layer in parakeratinized epithelium differ from that in orthokeratinized epithelium?
In parakeratinized epithelium, the keratin layer contains cells with both keratin and nuclei, unlike the keratinized layer in orthokeratinized epithelium.
128
How is the keratin layer in parakeratinized epithelium maintained?
Cells in the keratin layer are shed and lost, similar to those in orthokeratinized epithelium.
129
What is the clinical appearance of healthy attached gingiva?
It is opaque pink, with possible areas of melanin pigmentation, and when dried, it appears dull, firm, and immobile.
130
What is stippling, and how does it appear on the attached gingiva?
Stippling appears as small pinpoint depressions, giving the surface an orange-peel appearance.
131
What type of epithelium predominates in the attached gingiva?
A thick layer of mostly parakeratinized epithelium, with minor amounts of orthokeratinized epithelium.
132
What gives the attached gingiva its pink and opaque appearance?
The thick parakeratinized epithelium obscures the extensive vascular supply in the lamina propria.
133
What is the structure of the lamina propria in the attached gingiva?
It has tall and narrow connective tissue papillae.
134
Does the attached gingiva have a submucosa?
No, the lamina propria is directly attached to the underlying alveolar process, making the tissue firm and immobile.
135
What is the clinical appearance of the mucogingival junction?
It is a sharply defined, scalloped junction between the pinker attached gingiva and the redder alveolar mucosa.
136
How is the mucogingival junction classified histologically?
It is a dividing zone between the keratinized attached gingiva and the nonkeratinized alveolar mucosa.
137
What histological differences exist on either side of the mucogingival junction?
The pinkish attached gingiva has a thick epithelial layer, while the redder alveolar mucosa has a thin epithelial layer.
138
What types of mucosa meet at the mucogingival junction?
Masticatory mucosa (attached gingiva) and lining mucosa (alveolar mucosa).
139
What are exostoses, and where do they develop?
Exostoses are bony growths that develop on the facial/buccal surface of the alveolar processes.
140
Are exostoses usually benign or malignant?
They are usually benign and painless.
141
When do exostoses typically become noticeable?
They often go unnoticed unless they grow large enough to cause discomfort or complications.
142
How do exostoses typically appear?
They may appear unilaterally or bilaterally in the premolar and molar regions and can be lobulated or nodular.
143
What covers exostoses, and do they vary in size?
They are covered by oral tissue and can vary in size.
144
What is gingival hyperplasia?
Gingival hyperplasia is the overgrowth of the interproximal gingiva.
145
What can cause gingival hyperplasia?
It can be caused by certain drugs, such as seizure control medications (phenytoin sodium), antibiotics, or specific heart medications.
146
What layers of the gingival tissue can gingival hyperplasia affect?
It can affect both the epithelium and the lamina propria.
147
Can gingival hyperplasia be localized or generalized?
Yes, it can be either localized or generalized.
148
What layers are present in all forms of oral mucosa epithelium?
All forms of oral mucosa epithelium have a lamina propria deep to the basement membrane.
149
What is the main fiber group in the lamina propria?
The main fiber group is Type I collagen fibers.
150
What are the two layers of the lamina propria?
The papillary layer (superficial, with loose connective tissue, blood vessels, and nerve tissue) and the dense layer (deeper, with dense connective tissue and many fibers).
151
What lies between the papillary and dense layers of the lamina propria?
The capillary plexus, which provides nutrition to the layers.
152
What is the most common cell in the lamina propria?
The fibroblast, which synthesizes protein fibers and intercellular substance.
153
Is submucosa always present in the oral cavity?
No, submucosa may or may not be present deep to the dense layer of the lamina propria, depending on the region.
154
What does the submucosa typically contain if present?
It usually contains loose connective tissue and may include adipose tissue or salivary glands.
155
What structures might the submucosa overlie in the oral cavity?
It may overlie bone or muscle.
156
What tissues make up the major and minor salivary glands?
They are composed of epithelium and connective tissue.
157
What are the cells that produce saliva called?
They are called secretory cells.
158
What are the two types of secretory cells?
The two types are mucous cells and serous cells.
159
What is an acinus, and what is its structure?
An acinus is a group of secretory cells surrounded by a single layer of cuboidal epithelial cells with a central opening called a lumen where saliva is deposited.
160
What is the role of connective tissue in salivary glands?
The connective tissue forms the capsule surrounding the gland and the septa, which divide the gland into lobes and lobules.
161
What do serous salivary glands produce?
They produce a watery, thin fluid rich in digestive enzymes like amylase.
162
What is an example of a serous salivary gland?
The parotid gland.
163
What do mucous salivary glands produce?
They produce a thick, viscous mucus containing mucin, which acts as a lubricant.
164
What is an example of a mucous salivary gland?
The sublingual gland.
165
What are mixed salivary glands, and what do they contain?
Mixed salivary glands contain both serous and mucous cells.
166
What is an example of a mixed salivary gland?
The submandibular gland.
167
What causes pigmentation in the oral mucosa?
Pigmentation is caused by melanin, a pigment formed by melanocytes.
168
Where are melanocytes located in the oral mucosa?
They are found in the basal layer of the stratified squamous epithelium.
169
What are melanosomes, and what is their function?
Melanosomes are small cytoplasmic granules in melanocytes that store melanin pigment and inject it into neighboring basal epithelial cells.
170
How does melanin pigmentation appear clinically?
It appears as localized flat areas ranging in color from brown to brownish black.
171
What happens to pigmented cells during tissue regeneration?
Pigmented cells migrate to the surface of the oral mucosa during turnover.
172
How does the turnover time of oral mucosa compare to that of skin?
The turnover time of oral mucosa is faster than that of skin.
173
Which region of the oral cavity has the fastest turnover time?
The junctional epithelium of the gingival sulcular region, with a turnover time of 4 to 6 days.
174
Which region of the oral cavity has the slowest turnover time?
The hard palate, with a turnover time of 24 days.
175
What is the range of turnover times for other oral mucosa regions?
Turnover times range between 4 and 24 days.
176
What happens initially after an injury to the oral mucosa?
A clot forms from blood products, and the inflammatory response is triggered by white blood cells.
177
How does epithelial repair begin in the oral mucosa?
Epithelial cells at the periphery of the injury lose their desmosomal junctions and migrate to form a new epithelial surface layer beneath the clot.
178
Why is the clot important in the repair process?
The clot acts as a guide for forming a new epithelial surface and must be retained during the early days of repair.
179
What tissue forms during the repair of the lamina propria?
Fibroblasts migrate to produce granulation tissue, which is immature connective tissue with fewer fibers and increased blood vessels.
180
What replaces granulation tissue during healing?
Firmer, paler scar tissue replaces granulation tissue as healing progresses.
181
How does scar tissue in oral mucosa compare to scar tissue in the skin?
Oral mucosa has less scar tissue because it contains fewer fibers than the skin.
182
How is the tongue divided anatomically by the sulcus terminalis?
The sulcus terminalis divides the tongue into an anterior two-thirds (oral part) and a posterior one-third (pharyngeal part).
183
What is the foramen cecum, and where is it located?
It is a small pit-like depression located at the point where the sulcus terminalis points toward the pharynx.
184
What is the midline depression on the dorsal surface of the tongue called?
It is called the median lingual sulcus.
185
What is the pharyngeal part of the tongue, and where is it located?
The pharyngeal part, or base of the tongue, is the posterior one-third and lies within the oral part of the pharynx.
186
What is the oral part of the tongue, and where is it located?
The oral part, or body of the tongue, is the anterior two-thirds and lies within the oral cavity proper.
187
What is the lingual tonsil, and where is it located?
The lingual tonsil is an irregular mass of tissue located on the dorsal surface of the tongue’s base.
188
What is visible on the ventral surface of the tongue?
Large blood vessels called deep lingual veins and fringelike projections called the plica fimbriata are visible.
189
What type of muscle forms the core of the tongue?
The tongue’s core consists of striated muscle.
190
How do the muscle bundles differ between the anterior and posterior parts of the tongue?
In the anterior part, the muscle bundles are tightly packed with little intervening adipose tissue, while in the posterior part, adipose tissue is more abundant.
191
Where are minor salivary glands most numerous in the tongue?
They are numerous in the submucosa and muscular core of the posterior part of the tongue, particularly near the junction of the anterior and posterior parts.
192
What types of mucosa are present on the dorsal surface of the tongue?
The dorsal surface has both masticatory mucosa and specialized mucosa.
193
What type of epithelium is associated with the masticatory mucosa of the tongue?
It is generally covered by orthokeratinized stratified squamous epithelium.
194
What is the specialized mucosa on the dorsal surface of the tongue associated with?
It is associated with the lingual papillae.
195
What are the lingual papillae?
They are small, discrete structures or appendages of keratinized epithelium with both orthokeratinized and parakeratinized epithelium overlying a lamina propria.
196
Where are lingual papillae found on the tongue?
They are found on both the dorsal and lateral surfaces of the tongue.
197
What types of lingual papillae are associated with taste buds?
Fungiform, foliate, and circumvallate papillae.
198
What is a taste bud, and what is its structure?
A taste bud is a barrel-shaped organ of taste composed of 30 to 80 spindle-shaped cells extending from the basement membrane to the epithelial surface of the lingual papilla.
199
What is the turnover time for taste bud cells?
The turnover time for taste bud cells is about 10 days.
200
What are the two types of cells found in taste buds?
Supporting cells and taste cells.
201
Where are supporting cells located in the taste bud, and what is their function?
Supporting cells are located on the outer part of the taste bud and help maintain its structure.
202
Where are taste cells located in the taste bud, and what is their function?
Taste cells are located in the central part and have superficial taste receptors that detect dissolved food molecules.
203
What is a taste pore, and what is its role?
A taste pore is an opening in the most superficial part of the taste bud, where dissolved food molecules contact taste receptors.
204
How do sensory neuron processes interact with taste buds?
Sensory neuron processes are located among the cells in the inferior part of the taste bud and receive taste sensation messages.
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How is taste sensation transmitted to the brain?
Messages from taste receptors are sent to the central nervous system via connecting nerves, where they are identified as specific tastes.
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What factors can affect taste perception?
Factors include aging, color/vision impairments, hormonal influences, genetic variations, oral temperature, drugs and chemicals, CNS tumors (especially temporal lobe lesions), and congested noses.
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How are the four fundamental taste sensations differentiated?
They are differentiated due to four slightly different types of taste cells.
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How are the tastes experienced on the tongue?
Tastes are a result of blending the four fundamental sensations (sweet, sour, salty, and bitter) with other sensations from the tongue and interplay with smell.
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Can all regions of the tongue with taste buds detect all taste sensations?
Yes, all qualities of taste can be elicited from all regions of the tongue that contain taste buds.
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Has the traditional idea of tongue taste mapping been proven correct?
No, studies have shown that the concept of specific taste regions on the tongue is false.
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What are the four types of lingual papillae?
The four types are filiform, fungiform, foliate, and circumvallate papillae.
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Which type of lingual papillae is most common?
Filiform papillae are the most common.
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Where are filiform papillae located, and what do they look like?
They are located on the body of the dorsal surface of the tongue and are shaped like fine-pointed cones about 2 to 3 mm long.
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What function do filiform papillae serve?
They provide the velvety texture of the tongue and are sensitive to changes in the body.
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Do filiform papillae contain taste buds?
No, filiform papillae do not contain taste buds.
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What causes the white appearance of filiform papillae?
The increased amount of keratin at the surface forms a “snow-covered Christmas tree” arrangement.
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What is geographic tongue, and how does it appear clinically?
Geographic tongue appears as red and paler pink to white patches on the body of the tongue, resembling a geographic map, with patches that change shape over time.
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What other names are used for geographic tongue?
It is also known as benign migratory glossitis or erythema migrans.
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What causes the red and white patches in geographic tongue?
The red patches correspond to areas of filiform papillae undergoing parakeratinization, while the white patches correspond to areas undergoing orthokeratinization.
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Is geographic tongue associated with any symptoms?
It may be associated with soreness or a slight burning sensation on the tongue’s surface.
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What is black hairy tongue, and what causes it?
Black hairy tongue occurs when the usual shedding of the filiform papillae does not occur, leading to a thick layer of dead cells and keratin that becomes stained by tobacco, medicines, or chromogenic bacteria.
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Can fungal overgrowth contribute to black hairy tongue?
Yes, fungal overgrowth, possibly due to high doses of antibiotics or radiation therapy, can contribute to black hairy tongue.
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How can black hairy tongue be managed?
Brushing the tongue is recommended to promote tissue shedding and remove debris.
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Should black hairy tongue be recorded in a patient’s chart?
Yes, it should be noted in the patient record if present.
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What is hairy leukoplakia, and how does it appear clinically?
It is an irregular and corrugated white lesion that commonly occurs on the lateral border of the tongue.
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What is the primary cause of hairy leukoplakia?
Epstein-Barr virus (EBV) is considered the primary cause of the lesion.
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In which patients is hairy leukoplakia most commonly found?
It is most commonly found in patients with HIV but can also occur in those who are not HIV-infected.
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Why is brushing the dorsal surface of the tongue important?
Brushing the tongue is important for overall oral hygiene and to reduce bad breath (halitosis).
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What contributes to bad breath in the oral cavity?
Microbial colonization by dental biofilm on the tongue’s surface is a significant contributing factor to bad breath.
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Where are fungiform papillae located, and what is their clinical appearance?
They are located on the body of the dorsal surface of the tongue and appear as reddish dots that are slightly raised and mushroom-shaped, with a diameter of about 1 mm.
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Are fungiform papillae found near the sulcus terminalis?
No, they are not found near the sulcus terminalis.
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What are the histologic features of fungiform papillae?
They have a thin layer of orthokeratinized or parakeratinized epithelium overlying a highly vascularized core of lamina propria, giving them their redder appearance.
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Do fungiform papillae contain taste buds?
Yes, a variable number of taste buds are located in the most superficial part of the epithelial layer.
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What is the primary function of fungiform papillae?
Their function is taste sensation.
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Where are foliate papillae located, and what is their clinical appearance?
They are located on the lateral surface of the tongue in its most posterior part and appear as 4 to 11 vertical ridges running parallel to each other.
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Are foliate papillae often mistaken for other conditions?
Yes, they can occasionally be mistaken for tumors or inflammatory disease.
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What are the histologic features of foliate papillae?
They are leaf-shaped structures with a layer of orthokeratinized or parakeratinized epithelium overlying a core of lamina propria.
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Do foliate papillae contain taste buds?
Yes, taste buds are located in the epithelial layer on the lateral parts of the leaf-shaped structures.
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What is the primary function of foliate papillae?
Their function is taste sensation.
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Where are circumvallate papillae located, and what is their clinical appearance?
They are located on the dorsal surface of the tongue, just anterior to the sulcus terminalis, and appear as 7-15 large, raised, mushroom-shaped structures arranged in an inverted V-shape.
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How does the size of circumvallate papillae compare to other papillae?
They are larger than fungiform papillae, measuring 3 to 5 mm in diameter.
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What are the histologic features of circumvallate papillae?
They are surrounded by orthokeratinized or parakeratinized epithelium overlying a core of lamina propria, with hundreds of taste buds located in the epithelium around the entire base.
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What is the function of von Ebner salivary glands associated with circumvallate papillae?
These serous salivary glands flush the area around the taste pores to allow new taste sensations to be introduced.
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What is the primary function of circumvallate papillae?
Their function is taste sensation.
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What is a fissured tongue, and how is it characterized?
A fissured tongue is a condition characterized by grooves of varying depth along the dorsal and lateral aspects of the tongue.
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What is the suspected cause of a fissured tongue?
Although the exact cause is unknown, it is suspected to have a polygenic mode of inheritance and often recurs in families.
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Is a fissured tongue symptomatic?
No, patients are usually asymptomatic, and it is often found incidentally during routine intraoral examinations.
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What conditions are associated with a fissured tongue?
It is frequently seen in Down syndrome and in association with geographic tongue.
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Where in the oral cavity is oral cancer most commonly found?
One of the most common sites is the lateral border of the tongue.
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How does oral cancer on the tongue initially present?
It is initially asymptomatic and painless, with a flat lesion.
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What happens as oral cancer on the tongue progresses?
The lesion may become painful as it invades surrounding nerve tissue and can develop into an exophytic growth, protruding outward from the surface.
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What is the attached gingiva, and where is it located?
The attached gingiva is the gingival tissue that tightly adheres to the bone around the roots of the teeth.
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What is interdental gingiva, and what does it form?
Interdental gingiva is an extension of attached gingiva between adjacent teeth, forming the interdental papillae.
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What is the gingival col, and how is it shaped?
The gingival col is a nonvisible concave shape between the facial and lingual gingival surfaces, apical to the contact area.
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What factors influence the depth and width of the gingival col?
The depth and width vary depending on the expanse of the contacting tooth surfaces.
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How is attached gingiva classified?
It is classified as masticatory mucosa.
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What is the clinical appearance of healthy attached gingiva?
It is pink, firm, and immobile, with possible areas of melanin pigmentation and varying amounts of stippling.
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What is the marginal gingiva, and where is it located?
The marginal gingiva (or free gingiva) is located at the gingival margin of each tooth and is continuous with the attached gingiva.
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How does the marginal gingiva differ from attached gingiva in clinical appearance?
While both appear pink, dull, and firm, the marginal gingiva lacks stippling and is mobile or free from the underlying tooth surface.
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What separates the attached gingiva from the marginal gingiva?
The free gingival groove separates these two types of gingiva.
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How is the marginal gingiva classified?
It is also classified as masticatory mucosa.
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What type of epithelium covers the attached gingiva?
The attached gingiva is covered by a thick layer of mostly parakeratinized stratified squamous epithelium.
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What feature of the lamina propria gives the attached gingiva its stippling appearance?
The tall, narrow connective tissue papillae in the lamina propria alternate with rete ridges, giving it a stippled appearance.
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How is the interface between the epithelium and lamina propria in attached gingiva described?
It is highly interdigitated, contributing to its firmness and immobility.
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What makes the attached gingiva firm and immobile?
The lamina propria is directly attached to the underlying bony jaws.
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What type of epithelium covers the marginal gingiva?
The marginal gingiva has an overlying layer of orthokeratinized stratified squamous epithelium.
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Why is the marginal gingiva more mobile than attached gingiva?
It is not attached to the underlying bony alveolar process.
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What type of tissue is found in the col area of the gingiva?
The tissue in the col is nonkeratinized.
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What is biologic width?
Biologic width is the microscopic distance between the base of the gingival sulcus and the crest of the alveolar bone.
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Which structures form the biologic width?
The junctional epithelium and connective tissue attachment to the root surface of a tooth.
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What is the commonly stated measurement for biologic width?
The biologic width is commonly stated to be 2.04 mm.
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Why is biologic width important for clinicians?
It is crucial for determining the position of restorative margins and their impact on postsurgical tissue position.
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What are two possible outcomes if restorative margins violate the biologic width?
Bone resorption may occur to recreate space for the biologic width, or more commonly, gingival inflammation develops around the tooth.
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Why is biologic width a significant consideration for anterior restorations?
Inflammation caused by violations can compromise the esthetic and functional outcomes of anterior restorations.
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What is the dentogingival junction?
It is the junction between the tooth surface and the gingival tissue.
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What two types of epithelium form the dentogingival junctional tissue?
The sulcular epithelium (SE) and the junctional epithelium (JE).
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What does the sulcular epithelium (SE) create?
It stands away from the tooth, creating the gingival sulcus.
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What fills the gingival sulcus?
The sulcus is filled with gingival crevicular fluid (GCF).
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What is the source of gingival crevicular fluid (GCF)?
It originates from the adjacent blood supply in the lamina propria.
280
What components are found in gingival crevicular fluid (GCF)?
It contains immunologic components, blood cells, and sticky plasma proteins that help adhere the lining tissue.
281
What is the average depth of a healthy gingival sulcus?
The depth varies from 0.5 to 3 mm, with an average of 1.8 mm.
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What is the junctional epithelium (JE), and where is it located?
The JE is a deeper extension of the sulcular epithelium that lines the floor of the gingival sulcus and is attached to the tooth surface.
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How is the junctional epithelium attached to the tooth?
It is attached by way of an epithelial attachment (EA).
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How does the JE surround the tooth?
It surrounds the tooth like a turtleneck, forming a cross-section resembling a thin wedge.
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What does the free gingival groove correspond to in the JE?
The free gingival groove on the outer surface corresponds to the apical border of the inner JE but not to the depth of the gingival sulcus.
286
What type of epithelium makes up the sulcular epithelium (SE)?
The SE consists of stratified squamous epithelium.
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How is the SE related to the surrounding gingival tissue?
It acts as a transition tissue between the gingival epithelium and the junctional epithelium.
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Is the sulcular epithelium keratinized?
No, the SE is nonkeratinized, unlike the keratinized marginal and attached gingiva.
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How does the interface between the SE and the lamina propria differ from other gingival tissues?
The interface is relatively smooth compared to the strongly interdigitated interface of the marginal and attached gingiva.
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What is the interface between the junctional epithelium (JE) and the lamina propria like?
It is also relatively smooth, without rete ridges or connective tissue papillae.
291
What is periodontal disease?
It is an inflammatory disease that affects the soft and hard structures supporting the teeth.
292
What are the two stages of periodontal disease?
The early stage is gingivitis, and the later stage is periodontitis.
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How does gingivitis differ from periodontitis?
Gingivitis involves inflammation with no loss of attachment and is reversible, while periodontitis involves loss of periodontal structures and is irreversible.
294
What happens to the gingiva during active periodontal disease?
Both the marginal and attached gingiva, especially the interdental papillae, may become enlarged and spongy due to edema in the lamina propria.
295
What is McCall’s festoon, and how does it appear?
McCall’s festoon is a lifesaver-shaped edema of the marginal gingiva caused by the inflammatory response.
296
What is gingival recession?
It is the apical migration of the gingival margin.
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What are some causes of gingival recession?
Causes include periodontal disease, tooth position, incorrect toothbrushing methods, abfraction from occlusal stress, a thin scalloped gingival biotype, aging, and tight frenal attachments.
298
What is a Stillman cleft, and what causes it?
A Stillman cleft is a cleft-like area of gingival recession, often related to occlusal trauma such as bruxism, clenching, or misaligned bites.
299
What is a key clinical sign of active periodontal disease?
Bleeding on probing (BOP) is one of the first clinical signs.
300
Why does bleeding occur during probing in gingivitis?
The periodontal probe damages the increased blood vessels in the capillary plexus of the lamina propria, which are closer to the surface due to ulceration of the junctional epithelium.
301
Does bleeding on probing indicate that the clinician is hurting the patient?
No, BOP occurs even with a gentle touch and indicates inflammation.
302
Why do patients who use nicotine products rarely show bleeding on probing?
Nicotine causes vasoconstriction, narrowing the blood vessels and reducing bleeding.
303
How should bleeding on probing be recorded?
It should be documented per individual tooth and surface in the patient’s chart.
304
What happens to the amount of gingival crevicular fluid (GCF) during periodontal inflammation?
The amount of GCF increases to fight microbial attacks against periodontal pathogens.
305
What passes through the epithelial wall during periodontitis?
Relatively large amounts of fluid pass through the more permeable epithelial wall.
306
What forms when GCF contains cellular debris and large populations of PMNs (polymorphonuclear leukocytes)?
It forms a whitish exudate, also known as suppuration or pus.
307
How is suppuration clinically observed?
It is noted as visible white fluid resulting from cellular debris and inflammation.
