Final Flashcards
(162 cards)
1
Q
Sharpey’s fibers are located in which of the following types of dental tissue?
a. enamel
b. dentin
c. cementum
d. pulp
A
cementum
Sharpey fibers are a part of the collagen fibers from the periodontal ligament that are each partially inserted into the outer part of the cementum at 90 degrees or perpendicular to the cemental surface (as well as the alveolar process on their other end) as they are inserted on the other end, the alveolar process.
2
Q
On the lateral aspect of the mandible, the stout, flat plate of the
__________ that extends upward and backward
from the body of the mandible on each side
A
ramus
3
Q
A type of cleft lip can result during prenatal development from the lack of fusion between _____ processes.
a. mandibular and maxillary
b. medial nasal and maxillary
c. lateral nasal and medial nasal
d. two lateral nasal
e. lateral nasal and maxillary
A
b.medial nasal
and
maxillary
4
Q
As the tongue develops still further, the copula of the tongue base, after overgrowing the second branchial arch, merges with the anterior swellings of the first branchial arch of the tongue body, with the fusion is superficially demarcated by the:
a. sulcus terminalis.
b. tuberculum impar.
c. copula.
d. median lingual sulcus.
A
a.
sulcus terminalis.
5
Q
Both the attached gingiva and buccal mucosa are mainly pinkish in color and
not reddish due to the:
a. vascularity of the lamina propria.
b. closeness to bone tissue.
c. decreased number of melanocytes.
d. increased thickness of the epithelial layers.
A
d.increased thickness of the epithelial layers
6
Q
By the end of the first week of prenatal development, the blastula stops traveling and undergoes:
a. implantation.
b. migration.
c. disintegration.
d. amniocentesis.
A
a. Implantation
By the end of the first week, the blastocyst stops traveling and undergoes implantation; thus it becomes embedded in the prepared endometrium, the innermost lining of the uterus on its back wall.
7
Q
Cell renewal of the junctional epithelium takes place in the:
a. internal basal lamina.
b. external basal lamina.
c. lamina propria.
d. basal layer of the tissue
A
d.basal layer of the tissue
8
Q
cellular cementum is most likely found around which of the following root regions?
a. cervical part of the root
b. entire root of an unerupted tooth
c. apical part of the root
d. furcation region of the root
A
c. apical part of the root
Cellular cementum** consists of the **last layers of cementum deposited over the acellular cementum**, mainly in the **apical one-third of each root**. At least one layer of acellular cementum covers the entire outer surface of each root with **many more layers covering the cervical one third near the cementoenamel junction.
9
Q
Dentin forming cells?
A. Ameloblasts
B. Odontoblasts
C. Outer cells (dental papilla)
E.Preameloblast
A
Odontoblasts
10
Q
Dentin in a mature tooth is on the average about ______ mineralized by weight.
a. 50%
b. 65%
c. 70%
d. 96%
A
c. 70%
Mature dentin is by weight 70% inorganic material or mineralized. The alveolar process is by weight 50% inorganic material. Mature cementum is by weight 65% inorganic material. Mature enamel is by weight 96% inorganic material.
11
Q
Dentin in the mature tooth is produced as a result of secretion by:
a. cementoblasts.
b. fibroblasts.
c. osteoblasts.
d. odontoblasts.
A
d. odontoblasts
Apposition of dentin by odontoblasts**, unlike enamel, **occurs throughout the life of the tooth, filling in the pulp chamber of both the crown and root.
12
Q
Predentin is the initial material laid down by the:
a. odontoblasts.
b. ameloblasts.
c. preameloblasts.
d. odontoclasts.
A
a. odontoblasts.
Predentin is a mesenchymal product consisting of nonmineralized collagen fibers produced by the odontoblasts. Ameloblasts —> preameloblasts —–> enamel. Odontoclasts are active during eruption, removing parts of the primary tooth.
13
Q
During root development, the Hertwig epithelial root sheath is entirely composed of:
a. all layers of the enamel organ.
b. enamel organ and dental papilla.
c. inner and outer cells of the dental papilla.
d. inner and outer enamel epithelium.
A
d.
inner and outer
enamel epithelium.
14
Q
During the cap stage of tooth development, the tooth germ consists of:
a. enamel organ and dental sac.
b. enamel organ and dental papilla.
c. enamel organ, dental sac, and dental papilla.
d. dental sac and dental papilla.
A
c. enamel organ,
dental sac,
and
dental papilla.
15
Q
During the cell cycle, interphase involves the cells engaging in:
a. organelle replacement.
b. substance destruction.
c. chromatin removal.
d. centrosome reduction.
A
a. organelle replacement.
Interphase: Period when a cell is between divisions but is
growing and functioning.
Mitosis: Interphase→Prophase→Metaphase→Anaphase→Telophase
IPM AT
16
Q
During the sixth week of prenatal development, within the embryonic period, the bilateral maxillary processes give rise to paired:
a. lateral nasal processes.
b. medial nasal processes.
c. palatal shelves.
d. mandibular processes.
A
c. palatal shelves.
17
Q
During tongue development, what does the epiglottic swelling develop from?
a. Outer parts of the maxillary process
b. Inferior growth of the intermaxillary segment
c. Palatal shelves of the maxillary process
d. First four branchial arches
A
d. First four branchial arches
* posterior swelling that develops from the mesenchyme of the fourth branchial arches marking the development of future epiglottis*
18
Q
During tooth development, both the pulp and the dentin in the mature tooth are products of the:
a. dental papilla.
b. enamel organ.
c. dental sac.
d. epithelium.
A
a. dental papilla.
* Dentin and pulp tissue have similar embryologic backgrounds because both are originally derived from the dental papilla of the tooth germ during tooth development.*
19
Q
During what period of prenatal development is most of the permanent dentition formed?
a. Preimplantation period
b. Embryonic period
c. Fetal period
d. Both embryonic and fetal period
A
c. Fetal period
20
Q
During which week of prenatal development does the neural plate differentiate?
a. Second week
b. Third week
c. Fourth week
d. Fifth week
A
b. Third week
* A specialized group of cells differentiates from the ectoderm and is now considered neuroectoderm. These cells are localized to the neural plate of the embryo, a central band of cells that extends the length of the embryo, from the cephalic end to the caudal end, during the third week of prenatal development. This plate undergoes further growth and thickening, which causes it to deepen and invaginate inward, forming the neural groove.*
21
Q
During which week of prenatal development is the palate completed?
a. Fifth
b. Eighth
c. Tenth
d. Twelfth
A
d.
Twelfth
22
Q
Embryonic layers (germ layers)
A
increased number of embryonic cells within the blastocyst.
23
Q
Enamel hypocalcification is a type of enamel dysplasia that involves:
a. an increased number of ameloblasts.
b. a reduction in the quantity of enamel matrix.
c. grooves and pitting on the enamel surface.
d. interference in the metabolic processes of ameloblasts.
A
d. interference in the metabolic processes of ameloblasts.
24
Q
Enamel matrix is a(n) _____ product because ameloblasts are derived from the inner enamel epithelium of the enamel organ.
a. ectodermal
b. endodermal
c. mesodermal
d. neural crest cell
A
a.ectodermal = outer
25
**Enamel matrix** is produced by the _____ cells.
a. ameloblasts
b. odontoblasts
c. odontoclasts
d. cementoblasts
a.**Ameloblasts**
26
**Failure of fusion** of the **palatal shelves** with the **primary palate** or each other will result in?
A. Branchial cleft cyst
B. Cleft palate
C. Medial nasal process
D.Zygote
**Cleft palate**
27
Found in **early prenatal development**, the **neural tube** will **form in the future** which of the following **structures**?
a. Heart
b. Spinal cord
c. Face
d. Digestive tract
**Spinal cord**
*As further growth of the neuroectoderm occurs, the **neural tube** is formed during the **fourth week** by the **neural folds undergoing fusion** at the most superior part. The **neural tube forms the future spinal cord** as well as other **neural tissue** of the **central nervous system.***
28
From the following list of muscles, select which are considered **muscles of mastication**. (*Select all that apply*.)
a. Buccinator
b. Risorius
c. Platysma
d. Temporalis
e. Masseter
d. **Temporalis**
e. **Masseter**
29
From which **embryonic layer** is **mesoderm** derived during prenatal development?
a. Epiblast layer
b. Hypoblast layer
c. Endoderm
d. Neuroectoderm
a.**Epiblast layer**
30
How many **buds** in the **dental lamina** appear along each **dental arch** during **odontogenesis** of the primary dentition?
a. 5
b. 10
c. 15
d. 20
b.
## Footnote
**10**
31
How many **phases** are within **mitosis** or cell division?
a. One
b. Two
c. Three
d. Four
d. **Four**
**1. Prophase**
**2. Metaphase**
**3. Anaphase**
**4. Telophase**
32
How many **X-type chromosomes** are necessary for the **embryo** to become of the **female gender** when present during **prenatal development**?
a. One
b. Two
c. Three
d. Four
**Two**
***A person is born with 23 pairs of chromosomes - a total of 46.** The photographic analysis of a person’s **chromosomes** is done by orderly arrangement of the pairs in a karyotype, with the **sex** known by the presence of either **XX chromosomes for females** or **XY for males.***
33
In **what direction** do the **imbrication lines** of **von Ebner** run?
a. at 45 degrees to the DEJ
b. at 90 degrees to the dentinal tubules
c. at 45 degrees to the inner pulpal wall
d. at 90 degrees to the periodontal ligament
b. at **90 degrees** to the **dentinal tubules**
* The imbrication lines of von Ebner are incremental lines or bands that stain darkly in a section of dentin. They run at 90 degrees to the dentinal tubules.*
34
In which **location** is the cell body of the **odontoblas**t found in a **mature** healthy **erupted tooth**?
a. along the dentinoenamel junction
b. along the outer pulpal wall
c. near the dentinocemental junction
d. near the pulpal core
b. along the **outer pulpal wall**
* The **odontoblasts** are located only along the **outer pulpal wall**. **Only their cell bodies are located in the pulp.***
35
in which part of the **alveolar process** is the loss of bone from **periodontitis first evident**?
a. interradicular bone
b. basal bone
c. supporting alveolar bone
d. alveolar crest
d **alveolar crest**
*The bone loss from periodontitis is **first evident** in the most coronal part of the **alveolar bone proper**, the **alveolar crest,** which looks moth eaten both microscopically and radiographically. The alveolar process loss of the jaws, which involves the presence of the roots of the teeth, progresses apically to involve the interradicular bone if the tooth is multirooted, as well as the surrounding supporting alveolar bone, but does not involve the inferior bone of the jaws, the basal bone.*
36
In which **week** of prenatal development does **facial development begin** in the embryo?
a. Second
b. Fourth
c. Fifth
d. Eighth
b.**Fourth**
37
**Lack of initiation** within the **dental lamina** results in the **absence of a single tooth or multiple teeth**, producing:
a. supernumerary teeth.
b. anodontia.
c. dens in dente.
d. germination.
b. **anodontia.**
## Footnote
**(6-7th week)**
38
**Lateral pulp canals** within the **pulp chamber** extend:
a. from pulp tissue to the periodontal ligament.
b. vertically toward the cementum.
c. between two pulp canals, as a bridge.
d. from the chamber, parallel to another canal.
a. from **pulp tissue** to the **periodontal ligament.**
***Accessory canals** are also called **lateral canals** because they are **usually located** on the **lateral surface of the roots** of the teeth, but this is **not always** the case because **they can be found anywhere along the root surface.***
39
Name the **3 major salivary glands**
1. Stensen's duct (Parotid)
2. Bartholin's duct (Sublingual)
3. Wharton's duct (Submandibular)
40
**Nonsuccedaneous permanent teeth** develop from **buds** that grow off an extension of:
a. each successional dental lamina.
b. both paired palatal shelves.
c. the posterior part of the intermaxillary segment.
d. each primary second molar’s dental lamina.
d. each primary **second molar’s dental lamina**.
41
on **radiographs**, the **periodontal ligament** appears as a:
a. radiopaque line covering the alveolar bone proper
b. lamina dura surrounding the alveolus
c. radiolucent space surrounding the alveolus
d. spongy material between the alveolus and alveolar bone proper
c. **radiolucent space surrounding the alveolus**
* The **periodontal ligament** appears on radiographs as a **radiolucent area (or darker)** located between the d**enser radiopaque (or lighter) lamina dura** of the **alveolar bone proper** and the **similar radiopaque (or lighter) cementum.***
42
On what structure do **BOTH heads** of the **masseter muscle originate**?
a. Zygomatic process of the maxilla
b. Coronoid process
c. Zygomatic process of the frontal bone
d. Zygomatic arch
d.**Zygomatic arch**
43
On which of the following orofacial tissue is the **linea alba located**?
a. Attached gingiva
b. Marginal gingiva
c. Labial mucosa
d. Buccal mucosa
d.**Buccal mucosa**
44
**Secondary dentin** usually forms within the tooth:
a. after the completion of the apical foramen.
b. before the completion of the apical foramen.
c. nearest to the dentinoenamel junction.
d. in response to tooth trauma.
a. **after** the **completion** of the **apical foramen.**
***Secondary dentin** is formed after the **completion** of the **apical foramen**(s) and continues to form throughout the life of the tooth. **Primary dentin** is formed in a tooth **before** the **completion** of the **apical foramen(s)** of the root, which is the opening in the root’s pulp canal. **Mantle dentin** is the **first predentin** that forms near the **DEJ.** **Tertiary dentin** forms quickly in **localized regions** in response to a **localized tooth trauma** to the **exposed dentin.***
45
Surrounding the teeth in the alveoli and **covering the alveolar processes** is the \_\_\_\_\_, which is composed of a **firm pink tissue.**
a. gingiva
b. minor salivary glands
c. Fordyce spots
d. linea alba
a.**gingiva**
46
What do the **muscles of mastication** work with to accomplish **movements** of the **mandible**?
a. Maxillae
b. Temporal bone
c. Temporomandibular joint
d. Zygoma
e. Hard palate
c. **Temporomandibular joint**
47
the **alveolar bone proper** of the **jaws** in a mature adult refers to the:
a. cancellous bone between the alveoli
b. layer of compact bone lining the alveolus
c. part of the jaw that houses the teeth
d. done surrounding the lamina dura
b. **layer** of **compact bone** lining the **alveolus**
* The alveolar bone proper of the jaws makes up the lining of the tooth socket or **alveolus,** which is also considered to be the **lamina dura on radiographs**. The part of the jaws that **contains the roots** of the teeth is the **alveolar process** or **alveolar bone**. The **supporting alveolar bone** consists of both **cortical bone** and **trabecular bone**. The cortical bone consists of a plate of compact bone on both the facial and lingual surfaces of the alveolar process. The trabecular bone consists of cancellous bone that is located between the alveolar bone proper and the plates of cortical bone.*
48
the **alveolar process** between **two neighboring teeth** is specifically called the _____ bone
a. interdental
b. basal
c. interradicular
d. trabecular
a. **interdental**
***The alveolar process that separates two neighboring teeth is the interdental septum or interdental bone.** The part apical to the roots of the teeth is the basal bone, which then forms the body of the maxilla or body of the mandible. The alveolar process that separates the roots of the same tooth is the interradicular septum or interradicular bone. The trabecular bone consists of cancellous bone that is located between the alveolar bone proper and the plates of cortical bone.*
49
the **anchorage** of the **tooth** to the **alveolar process** is mediated through which of the following?
a. interdental ligament
b. sharpey fibers
c. oxytalan fibers
d. both sharpey and oxytalan fibers
b. **Sharpey's fibers**
* Sharpey fibers in alveolar bone proper are each inserted at 90 degrees or perpendicular to the bone to mediate the anchorage of the tooth. A principal fiber of the periodontal ligament is the interdental ligament. Oxytalan fibers are a fiber type related to elastic fibers; they appear to consist of the microfibrillar component only, thereby resembling very immature elastic fibers.*
50
The **attached gingiva** of the **oral cavity** consists of which type of **oral mucosa**?
a. Alveolar mucosa
b. Masticatory mucosa
c. Specialized mucosa
d. Lining mucosa
b. **Masticatory mucosa**
*masticatory mucosa is a type of oral mucosa
noted for its **rubbery surface texture and resiliency.** Masticatory mucosa
includes that of the **hard palate, attached gingiva, and dorsal surface
of the tongue**. Mucosa associated with**keratinized stratified squamous** epithelium.*
51
the **cementoblasts originate** during **tooth development** from which of the following **embryonic structures**?
a. enamel organ
b. dental papilla
c. dental sac
d. both enamel organ and dental papilla
c. **dental sac**
***Cementum** and its cells, the **cementoblasts**, develop from the **dental sac** and form on the **root after the disintegration of Hertwig epithelial root sheath.** The **dental papilla** gives rise to the **dentin** and its **odontoblasts** as well as the **pulp** and its **_fibroblasts_**. The **enamel organ** gives rise to the **enamel** and its **ameloblasts**.*
52
The **dark, arc-like areas** in **histologic sections** of a **tooth** are **what type** of **dentin**?
a. Tomes granular layer
b. mantle dentin
c. circumpulpal dentin
d. interglobular dentin
d. **interglobular dentin**
* The dark, arclike areas in a stained histologic section in a tooth are considered **interglobular dentin.** In these areas, only **primary mineralization has occurred within the predentin, and the globules of dentin do not fuse completely.** Tomes granular layer is most often found in the peripheral part of dentin beneath the root’s cementum. Mantle dentin is the first predentin that forms near the dentinoenamel junction. Deep to the mantle dentin is the layer of dentin around the outer wall of pulp, the circumpulpal dentin, which makes up the bulk of the dentin in a tooth.*
53
The **dental lamina** is an embryonic structure that **develops from** the:
a. oral epithelium.
b. mesenchyme.
c. neural crest cells.
d. endodermal layer.
a. **oral epithelium**.
54
The **development of the neck parallels** the development of the **face** over time, beginning during the **fourth week** of prenatal development within the **embryonic period** and **completed** during the _____ period.
a. preimplantation
b. embryonic
c. fetal
d. both the embryonic and fetal
c.**fetal**
55
The developmental disturbance of **cleft lip** is *more* commonly found:
a. in males.
b. bilaterally.
c. on the right side.
d. on the lower lip.
a.in **males.**
56
The **facial development** that starts in the **fourth week** will be **completed** later in the _____ week within the fetal period.
a. fifth
b. sixth
c. eighth
d. twelfth
**twelfth**
57
The **folding** of the **embryo** during prenatal development causes _____ to be on the \_\_\_\_\_.
a. endoderm; inside of the embryo
b. ectoderm; inside of endoderm
c. endoderm; outside of the mesoderm
d. mesoderm; outside of the ectoderm
a.**endoderm**; inside of the **embryo**
58
The **fusion of the maxillary** and **medial nasal processes** to form the **upper lip** is **completed** during the end of the _____ week of prenatal development when the **grooves** between the processes are **obliterated.**
a. fourth
b. fifth
c. sixth
d. seventh
d.**seventh**
59
The fusion of the **two palatal shelves** with the primary palate is dependent on the:
a. ingrowth from the maxillary arch.
b. change in position of the paranasal sinuses.
c. continued vertical growth of all the processes.
d. change in the position of the tongue.
d.
change in the position of the **tongue**.
60
The **initiation stage** of **odontogenesis** *mainly* involves the process of:
a. differentiation.
b. proliferation.
c. induction.
d. morphogenesis.
c. **induction (6-7th week)**
## Footnote
**I -- I**
**B--P**
**C--PDM**
**B--PDM**
**A--IP**
**M--M**
61
The **interdental gingiva** assumes a **nonvisible concave** form **between** the **facial and lingual gingival surfaces** called the:
a. col.
b. papilla.
c. free gingival crest.
d. gingival apex of the contour.
a.**Col.**
62
the **lamina dura** noted on **radiographs** corresponds to which of the following structures?
a. basal bone of the both jaws
b. buccal and lingual cortical plates of the jaws
c. supporting cancellous bone between the teeth
d. alveolar bone proper of the alveolar process
d. **alveolar bone proper** of the **alveolar process**
* The part of the alveolar bone proper of the alveolar process that is present on radiographs is considered the lamina dura, which is uniformly radiopaque (or lighter).*
63
The **line of demarcation** between the **attached gingiva** and the **alveolar mucosa** is the:
a. mucogingival junction.
b. interdental gingiva.
c. mucobuccal fold.
d. marginal gingiva.
a.**mucogingival junction.**
64
The **lining mucosa** is **keratinized**.
True or False
**False**
**Lining mucosa = mucosa** associated with **nonkeratinized
stratified squamous epithelium.**
65
The **macrophages** found in the **connective tissue** are derived from:
a. neutrophils.
b. monocytes.
c. basophils.
d. mast cells.
b. **monocytes.**
Other cells found in **connective tissue** include migrated white
blood cells from the blood supply, such as **monocytes (macrophages),**
**basophils (mast cells)**
66
The **mandibular arch** during the **embryonic period** of prenatal development is the:
a. fusion of the two paired mandibular processes.
b. swelling found superior to the stomodeum.
c. structure that gives rise to the lateral nasal process.
d. posterior part of the hard palate.
a.**fusion** of the **two paired mandibular processes.**
67
The **maxillary processes** on **each side** of the **developing face** partially **fuse** with the **mandibular arch** on each side to create the:
a. philtrum.
b. tubercle.
c. labial commissures.
d. lower lip.
c.**labial commissures.**
68
the **most common cell** in the **periodontal ligament** is the:
a. cementoblast
b. fibroblast
c. odontoclast
d. osteoclast
b. **fibroblast**
* Like all connective tissue, the **fibroblast is the most common cell in the periodontal ligament, producing fibers and intercellular substance.** The cementoblast and odontoclast as well as the osteoclast are present in the periodontal ligament. The **cementoblast produces cementum** and the **odontoclast resorbs parts of the tooth during tooth shedding and eruption**. The **osteoclast resorbs the alveolar process.***
69
The **most common cell type** in connective tissue such as **pulp** is the:
a. endothelial cell.
b. fibroblast.
c. white blood cell.
d. odontoblast.
b. **fibroblast.**
* As in all forms of connective tissue, the **fibroblasts are the largest group of cells** in the **pulp**. The **odontoblasts** are the **second largest group of cells in the pulp,** but only their cell bodies are located in the pulp.*
70
the most **common type** of **connective tissue fiber** in the **periodontal ligament** is which of the following fiber groups?
a. collagen
b. elastic
c. oxytalan
d. collagen and elastic fibers
a. **collagen**
***All** the **fibers** in the **periodontal ligament** are **collagen in structure.***
71
The **neural crest cells** migrate from which **embryonic structures** during prenatal development?
a. Stomodeum
b. First branchial arch
c. Neural folds
d. Frontonasal process
c.**Neural folds**
72
The **outer cells** of the **dental papilla** are **induced** to differentiate during tooth development into:
a. pulp tissue.
b. preameloblasts.
c. odontoblasts.
d. cementoblasts.
c. **odontoblasts**.
73
the **periodontal ligament** directly **forms** from which part of the **developing tooth germ**?
a. enamel organ
b. dental papilla
c. dental sac
d. both enamel organ and dental papilla
c. **dental sac**
* Similar to the alveolar process, the **periodontal ligament** develops from the **dental sac** of the tooth germ. The **enamel organ** gives rise to the **enamel** and the **dental papilla** gives rise to the **dentin** and **pulp** of the tooth.*
74
The **philtrum** of the upper lip forms during **sixth week** of prenatal development from the:
a. mandibular processes.
b. medial nasal processes.
c. lateral nasal processes.
d. nasal placodes.
b.**medial nasal processes.**
75
The **pink labial mucosa** or **buccal mucosa** meets the redder _____ at the **mucobuccal fold.**
a. marginal gingiva
b. attached gingiva
c. alveolar mucosa
d. interdental papilla
c.**alveolar mucosa**
76
the **rests of Malassez** are **correctly** described as:
a. remnants of the outer enamel epithelium
b. similar to incremental growth limes in dentin
c. remnants of Hertwig root sheath
d. similar to the incremental growth lines in enamel
c. **remnants of Hertwig sheath**
* The epithelial rests of Malassez, which represent groups of epithelial cells, are **stranded in mature periodontal ligament after the disintegration of Hertwig epithelial root sheath during the formation of the root.***
77
The **specialized, metabolically active structures** within the cell are *generally* considered to be:
a. nuclear pores.
b. organelles.
c. chromosomes.
d. vacuoles.
b. **organelles**.
78
The **tongue develops** from multiple swellings derived from the:
a. outer parts of the maxillary process.
b. inferior growth of the intermaxillary segment.
c. palatal shelves of the maxillary process.
d. first four branchial arches.
d.
## Footnote
**first four branchial arches.**
79
The _____ are **rounded areas** of specialized, **thickened ectoderm** found at the location of **developing special sense organs.**
a. placodes
b. branchial arches
c. branchial pouches
d. processes
a.**placodes**
80
There are 4 muscles of mastication:
1. Masseter
2. Temporalis
3. Medial pterygoid
4. Lateral pterygoid
All attach to the mandible and are innervated by **V3**
Form in the **tenth week** of development
**First arches (mandibular arches)**
81
The **outer cells** of the **dental papilla** are induced to **differentiate** during
**tooth development** into:
a. pulp tissue.
b. preameloblasts.
c. odontoblasts.
d. cementoblasts.
c. **odontoblasts.**
82
What are the **dentin** levels **(% inorganic, organic, water**)
**70% inorganic (mineralized)**
**20% organic**
10% water
83
What are the **smaller extensions** of **coronal pulp** into the **cusps of posterior teeth termed**?
a. accessory canals
b. lateral canals
c. pulp horns
d. pulp canals
c. **pulp horns**
* The coronal pulp is located in the crown of the tooth. Smaller extensions of coronal pulp into the cusps of posterior teeth form the pulp horns.*
84
What *best* characterizes the **first week** of prenatal development so that the **blastocyst splits** into smaller and more numerous cells?
a. Implantation
b. Mitotic cleavage
c. Meiosis
d. Fertilization
b.**Mitotic cleavage**
85
What **bones** are **articulated** with the **TMJ**?
The **temporal bone** and **condyle** of the **mandible**
86
What does the **maxillary process** form from during the **fourth week** of prenatal development?
a. Lateral nasal processes
b. Mandibular arch
c. Intermaxillary segment
d. Medial nasal processes
b.**Mandibular arch**
87
What happens to the specific cells from the **enamel organ** that will differentiate into **preameloblasts**?
a. Their length shortens.
b. Their nuclei repolarize.
c. Their cellular contents mineralize.
d. They line up along the basement membrane.
b.Their **nuclei repolarize**.
88
What is the **angled part** of the **ameloblast** that **secretes** the **enamel matrix**?
a. Inner enamel epithelium
b. Repolarized preameloblasts
c. Tomes process
d. Disintegrating basement membrane
c. **Tomes process**
***(Ameloblast) = Tomes process → secretes enamel matrix***
89
What is the ***exact*** term for the **process** that **affords the development** of s**pecific tissue structure** or **differing form** due to **embryonic cell migration** and **inductive interactions**?
a. Folding
b. Morphogenesis
c. Proliferation
d. Appositional or interstitial growth
b.**Morphogenesis**
90
What is the known **etiology (cause)**of **supernumerary teeth**?
a. Hereditary factors
b. Occlusal trauma involvement
c. Interatogen considerations
d. Disintegration of associated membranes
a. **Hereditary factors**
## Footnote
**(6th-7th week Initiation stage)**
91
What is the term used to **describe the amount of time** it takes for **newly divided cells** to be **completely replaced** throughout a tissue?
a. Fusion
b. Mitosis
c. Turnover
d. Meiosis
c. **Turnover**
92
What structure is responsible for **root development**?
(A) Cervical Loop
(B) Hertwig Epithelial Root Sheath
(C) Cementocytes
(D) Cementogenesis
**Cervical Loop**; most cervical part of enamel organ
93
What term describes the **movement of the nuclei within the inner enamel epithelium** as the tissue forms into **preameloblasts**?
a. Dentinogenesis
b. Repolarization
c. Disintegration
d. Maturation
b. **Repolarization**
**movement of nuclei = repolarization**
94
What type of **dentin** occurs when **odontoblasts** in the area of the **traumatized tubules** may **perish** because of the **injury,** but **neighboring undifferentiated mesenchymal cells of the pulp** can move to the area and **become odontoblasts**?
a. reparative dentin
b. reactive dentin
c. sclerotic dentin
d. mantle dentin
a. **_reparative_ dentin**
* Odontoblasts in the area of the traumatized tubules may perish because of the injury, but neighboring undifferentiated mesenchymal cells of the pulp can move to the area and become odontoblasts, **forming a type of tertiary dentin**, **reparative dentin.** If the **tertiary dentin** is **formed by existing odontoblasts**, it is considered to be **reactive dentin**. A certain type of tertiary dentin, **sclerotic dentin occurs** when the **odontoblastic processes die** and leave the **dentinal tubules vacant**. **Mantle dentin** is the **first predentin** that forms.*
95
What type of tissue makes up the **bulk** of the **lamina propria** of the **oral mucosa**?
a. Connective tissue
b. Muscle tissue
c. Nerve tissue
d. Epithelium
a.**Connective tissue**
96
What’s the diff b/w meiosis and mitosis
Meiosis – The process of reproductive cell production that ensures the **correct number of chromosomes;** meiosis that takes place during **fertilization**.
Mitosis – **cell division** that occurs in phases and results in **two daughter cells;** Mitosis is a process that **takes place during tissue growth or regeneration**
97
When does **tongue development** occur during prenatal development?
a. During the fourth to fifth week
b. During the fourth to eighth week
c. During the eighth to tenth week
d. During the eighth to twelfth week
b.During the **fourth** to **eighth week**
the **body of the tongue** develops from the **first branchial arch**, and the **base of the tongue** originates later from the **second., third, and fourth** branchial arches.
98
when many of the **cementoblasts** become **entrapped** by the **cementum** they produce, they become:
a. odontoclasts
b. odontoblasts
c. cementocytes
d. dental sac cells
c. **cementocytes**
* During the later steps within the stage of apposition of cementum, many of the cementoblasts become entrapped by the cementum they produce, becoming cementocytes. After the appositional growth of cementum in layers, the cementoblasts that do not become entrapped in cementum line up along the cemental surface along the length of the outer covering of the periodontal ligament. When the undifferentiated cells of the dental sac come into contact with the newly formed surface of root dentin, these cells are induced to become cementoblasts. Odontoblasts are cells that produce dentin. Odontoclasts resorb dentin, cementum, and enamel during tooth shedding and eruption.*
99
Where does the **dental lamina** begin to form *first* in the developing dental arches?
a. Near the midline
b. Adjacent to the mental foramen
c. Over the region of the future molars
d. Adjacent to the developing temporomandibular joint
a. **Near the midline**
**(incisors)**
100
Where does the **initial teeth** for **both dentitions** develop?
a. Anterior maxillary region
b. Anterior mandibular region
c. Posterior maxillary region
d. Posterior mandibular region
b. **Anterior mandibular region**
***mandibular incisors***
101
Which embryonic structure is specifically responsible for the
**development of the root**?
a. Stellate reticulum
b. Enamel organ
c. Stratum intermedium
d. Cervical loop
d. **Cervical loop**
102
Which is the most **common type of nerves** associated with the **pulp** in a
**mature erupted tooth**?
a. myelinated
b. unmyelinated
c. myelinated and unmyelinated are in equal numbers
d. dead ones
b. **unmyelinated**
***Two types of nerves** are associated with the **pulp,** which includes mainly **unmyelinated nerves (70% to 80%)** and in lesser amounts, **myelinated nerves (20% to 30%).***
103
Which muscle listed below is **MOST superficial** in regard to location?
a. masseter muscle
b. medial pterygoid muscle
c. lateral pterygoid muscle
d. superior pharyngeal constrictor muscle
c. **lateral pterygoid muscle**
104
Which of the following basic tissue types is usually composed of **fewer cells spaced farther apart** and **containing larger amounts of matrix between the cells**?
a. Epithelium
b. Nerve tissue
c. Muscle tissue
d. Connective tissue
d. **Connective tissue**
105
Which of the following can occur that ***mainly*** involves the **abnormal development** of one or more **structures from ectoderm** within the **embryonic period**?
a. Treacher Collins syndrome
b. Ectodermal dysplasia
c. Congenital syphilis
d. Fetal alcohol syndrome
b.**Ectodermal dysplasia**
106
Which of the following **cell types** are ***not* renewable** during the lifetime of the tooth?
a. Ameloblasts
b. Odontoblasts
c. Odontoclasts
d. Cementoblasts
a. **Ameloblasts**
107
Which of the following descriptions concerning the **masseter muscle** is CORRECT?
a. most superficial muscle of the facial expression
b. originates from the zygomatic arch
c. insert on the medial surface of the mandible's angle
d. depresses the mandible during jaw movement
b. **originates from the zygomatic arch**
108
Which of the following embryonic structures becomes the
**dentinoenamel junction** during the completion of tooth development?
a. Inner cells of the dental papilla
b. Outer cells of the dental papilla
c. Outer enamel epithelium of the enamel organ
d. Basement membrane between the enamel organ and dental papilla
d.
**Basement membrane** between
the **enamel organ** and **dental papilla**
109
Which of the following **facial structures** is formed from the **mandibular arch** during prenatal development?
a. Forehead
b. Lower face
c. Philtrum
d. Nose
b.**Lower face**
110
which of the following **fiber groups** is a part of the **alveodental ligament** on a **single-rooted** adult tooth?
a. circular ligamnet
b. interdental ligament
gingival fiber group
d. apical group
d. **apical group**
* The **main principal fiber group** is the **alveolodental ligament,** which consists of **five fiber subgroups: alveolar crest, horizontal, oblique, apical, and interradicular on multirooted teeth.** The **circular ligament** is part of the **gingival fiber groups** and some consider these ligaments as a group to be part of the principal fibers but separate from the alveodental ligament. Another **principal fiber other than the alveolodental ligament** is the **interdental ligament.***
111
which of the following **fiber groups** of the **periodontal ligament** does **_not_**
**contribute significantly** to each **tooth's anchorage** in the **jaw**?
a. gingival fiber group
b. interdental fiber group
c. alveodental fiber group
d. interradicular fiber group
a. **gingival fiber group**
* The **gingival fiber group does not support the tooth in relationship to the jaws,** resisting any forces of mastication or speech; rather, this group **supports only the marginal gingiva to maintain the relationship to the tooth.** Instead, the **interdental and alveodental,** which the **interradicular fiber group** is part of, **supports the tooth in relationship to the jaws.***
112
Which of the following functions are performed by the **Golgi complex** within the cell?
a. Metabolizes foreign compounds
b. Produces ribosomes
c. Packages protein compounds
d. Produces energy for the cell
c. **Packages protein compounds**
* Golgi complex: **Responsible for** the packaging, segregation, and **transporting proteins into secretory vesicles** without losing or mixing of the cytoplasm within the cell*
113
Which of the following has **no stippling** & is **free** from **underlying tooth.**
A. attached gingiva
B. free gingival groove
C. Marginal Gingiva/Free Gingiva
D. free gingival width
Marginal Gingiva/Free Gingiva
114
Which of the following has the ***highest*** rate of **turnover**?
a. Oral epithelium
b. Sulcular epithelium
c. Junctional epithelium
d. All have an equally high rate
c.**Junctional epithelium**
***JE turnover = 4-6 days***
115
which of the following includes **both** the **supporting soft** and **hard dental tissue** between and including parts of the **tooth** and **surrounding bone**?
a. periodontal ligament
b. periodontium
c. alveolar bone proper
d. alveolar process
b. **periodontium**
* The periodontium consists of both the supporting soft and hard dental tissue between the tooth and the alveolar process, as well as parts of the tooth and alveolar process. Thus, the periodontium includes the **periodontal ligament** as well as the **alveolar process**, which includes the **alveolar bone proper.***
116
Which of the following includes the **tissue fluid** surrounding the **cell membrane** of the **odontoblast**?
a. lymph
b. gingival crevicular fluid
c. dentinal fluid
d. synovial fluid
c. **dentinal fluid**
* The **dentinal fluid** in the tubule includes the **tissue fluid** surrounding the **cell membrane** of the **odontoblast.** The **lymph** is found within the l**ymphatic system**. The **gingival crevicular fluid** is **located** within the **gingival sulcus.** The **synovial fluid** is found within the **temporomandibular joint**, surrounding the disc of the joint.*
117
Which of the following is a **projection** of the **basal or secretory** end of each **ameloblast** that faces the **dentinoenamel junction**?
a. Enamel spindle
b. Tomes process
c. Tomes granular layer
d. Hunter-Schreger bands
b. Tomes process
118
which of the following is **not** a part of the **gingival fiber group**?
a. interdental fiber group
b. circular fiber group
c. dentoperiosteal fiber group
d. alveologingival fiber group
a. **interdental fiber group**
* Another principal fiber other than the alveolodental ligament is the interdental ligament. **The gingival fiber group includes the fiber subgroups of the circular and dentogingival ligament, as well as both the alveologingival and dentoperiosteal ligaments.***
119
Which of the following is **_not_** associated with **dentinal hypersensitivity**?
a. enamel and cementum do not meet
b. dentin exposed due to caries process
c. blocking dentinal tubules
d. branching of dentinal tubules
c. **blocking dentinal tubules**
* Dentinal hypersensitivity can be treated somewhat successfully with solutions applied either by professionals or within over-the-counter dentifrices available to patients; these desensitizing agents **temporarily block the exposed open ends of the dentinal tubules**. **When dentin is exposed as a result of caries, the open dentinal tubules may be painful, causing dentinal hypersensitivity. However, many times it is the microscopic anatomy of the tooth that is the culprit; the enamel and cementum do not meet, leaving a gap with dentin exposed. Branching of the dentinal tubules containing the live odontoblastic processes throughout dentin adds to the overall level of exposure.***
120
Which of the following is the **BEST** term used for the **embryonic layer** located between the **ectoderm and the endoderm?**
a. Mesenchyme
b. Ectomesenchyme
c. Mesoderm
d. Mesiodens
c. **Mesoderm**
121
Which of the following is the **only sensation perceived** by the **brain** from the
**pulp's sensory nerves**?
a. taste
b. pain
c. temperature
d. pressure
b. **pain**
***The brain perceives all sensations directed to the pulp as sensations of pain.** Therefore, changes in temperature, vibrations, and chemical changes that affect the pulp or dentin by way of the **pulp’s nerves** are perceived only as **painful stimuli.***
122
Which of the following muscles can show **enlargement** due to **repetitive muscle contraction** associated with **clenching of the teeth** in a patient?
a. Buccinator muscle
b. Masseter muscle
c. Temporalis muscle
d. Zygomatic muscle
b.**Masseter muscle**
123
Which of the following **muscles** has **two bellies,** giving the muscles **two different origins**?
a. lateral pteryoid
b. geniohyoid
c. thyrohyoid
d. stylohyoid
a. **lateral pteryoid**
124
Which of the following **muscles inserts** onto the **coronoid process**?
a. Lateral pterygoid muscle
b. Masseter muscle
c. Medial pterygoid muscle
d. Temporalis muscle
d.**Temporalis muscle**
125
Which of the following **muscles** is considered a **muscle of mastication**?
a. buccinator
b. risorius
c. mentalis
d. masseter
e. corrugator supercilii
d. **masseter**
126
Which of the following muscles is involved in the **lateral deviation** of the **mandible**?
a. masseter muscle
b. medial pterygoid muscle
c. lateral pterygoid muscle
d. temporalis muscle
e. digastric muscle
c. **lateral pterygoid muscle**
127
Which of the following muscles when **contracted** allows for the **retraction of the mandible**?
a. Masseter muscle
b. Temporalis muscle
c. Lateral pterygoid muscle
d. Medial pterygoid muscle
b.**Temporalis muscle**
128
Which of the following muscles when **unilaterally contracted deviates** the **mandible to one side**?
a. Masseter muscle
b. Lateral pterygoid muscle
c. Medial pterygoid muscle
d. Temporalis muscle
b.**Lateral pterygoid muscle**
129
Which of the following occurs with the **deposition of minerals** into **mature enamel**?
a. Demineralization
b. Erosion
c. Remineralization
d. Abfraction
c. **Remineralization**
130
Which of the following **organelles** in a cell can appear microscopically either **smooth or rough**?
a. Golgi complex
b. Lysosomes
c. Cytoskeleton
d. Endoplasmic reticulum
d. **Endoplasmic reticulum (ER)**
**ER** = **Membrane-bound organelle with**
**channels** that is either **rough or smooth**
131
Which of the following permanent teeth can be considered **nonsuccedaneous**?
a. Incisors
b. Canines
c. Premolars
d. Molars
d. **Molars**
**Primary Molars → Premolars**
**Permanent molars grow on their own**
132
which of the following **situations** can be present at the **cementoenamel junction** in a **mature tooth**?
a. cementum overlaps enamel
b. enamel overlaps cementum
c. dentin overlaps enamel
d. pulp overlaps cementum or dentin
a. **cementum _overlaps_ enamel**
***Three possible types** of transitional interfaces may be present at the cementoenamel junction.: 1. **cementum may overlap the enamel** at the **cementoenamel junction**. 2. **cementum and enamel** may **meet end to end,** presenting no problems for either the clinician or patient. 3. a **gap may exist** **between** the **cementum and enamel, exposing dentin.***
133
Which of the following statements concerning **active eruption** of a **permanent succedaneous** tooth is *correct*?
a. The tooth erupts when the root is completed.
b. The shedding of the associated primary tooth is intermittent.
c. The first junctional epithelium is from the surrounding dental sac.
d. The tooth actively erupts as gingival recession occurs.
b. The **shedding** of the associated
**primary tooth** is **intermittent**.
(**irregular intervals**)
134
which of the following statements concerning the **oblique group** of the **periodontal ligament** is **correct**?
a. part of the gingival fiber group
b. found only in multi-rooted teeth
c. resists intrusive forces to the tooth
d. resists tilting forces to the tooth
c. **resists intrusive forces to the tooth**
* The **function** of the **oblique group** as part of the **alveodental ligament** of the **periodontal ligament** is to **resist intrusive forces**, which try to **push the tooth inward**, as well as **rotational forces**; it is found on both **single and multirooted teeth.***
135
Which of the following statements concerning tongue disturbances is *correct*?
a. Abnormalities of the tongue are common.
b. Ankyloglossia results from a long attachment of the lingual frenum.
c. Ankyloglossia may be associated with other craniofacial abnormalities.
d. Lingual frenum is never surgically cut anymore to free it.
c. **Ankyloglossia** may be associated with
other **craniofacial abnormalities**.
136
Which of the following **statements is correct** when considering **accessory canals**?
a. Teeth have a standard number.
b. Radiographs always indicate the number and position.
c. Gingival recession may expose the opening.
d. They are examined by placing radiolucent materials.
c. **Gingival recession may expose the opening.**
***Gingival recession may expose the opening of an accessory canal. Teeth have a variable number of these canals.** Radiographs do not always indicate the number or position of these canals, unless they are examined with instruments using radiopaque materials.*
137
which of the following structures is **_not_** considered part of the **periodontium**?
a. alveolar process
b. cementum
c. basal bone
d. periodontal ligament
c. **basal bone**
* The part **apical** to the **roots** of the teeth is the **basal bone**, which then forms the **body of the maxilla or body of the mandible and thus is not considered part of the periodontium.** The alveolar process, cementum, and periodontal ligament are all parts of the periodontium.*
138
Which of the following structures is ***not*** part of the **enamel organ**?
a. Stellate reticulum
b. Stratum intermedium
c. Odontoblastic layer
d. Outer epithelial cells
c. **Odontoblastic layer**
139
Which of the following structures **separates the epithelium** from the **connective tissue**?
a. Submucosa
b. Basement membrane
c. Periosteum
d. Endosteum
b. **Basement membrane**
140
Which of the following terms **associated with dentin** can be used to correctly **describe** the type that makes up the **largest part of the tooth's dentin**?
a. Tomes granular layer
b. mantle dentin
c. circumpulpal dentin
d. interglobular dentin
c. **circumpulpal dentin**
**Deep** to the **mantle dentin** is the layer of **dentin around the outer wall of pulp**, the **circumpulpal dentin**, which makes up the **bulk of the dentin in a tooth.**
141
which of the following terms **correctly describe**s the **alveolar bone proper**?
a. lamina propria
b. cancellous bone
c. mucoperiosteum
d. cribriform plate
d. **cribriform plate**
## Footnote
***The alveolar bone proper makes up the lining of the tooth socket or alveolus.** Although the a**lveolar bone proper** is composed of **compact bone,** it may be called the **cribriform plate** because it **contains numerous holes** where **Volkmann canals with their nerves and blood vessels pass from the alveolar process into the periodontal ligament.** The lamina propria is the connective tissue component of the oral mucosa. A mucoperiosteum is a combined structure consisting of a mucous membrane, in the case of the oral cavity, the epithelium and lamina propria of the oral mucosa, with the periosteum of bone. The trabecular bone consists of cancellous bone or spongy bone that is located between the alveolar bone proper and the plates of cortical bone.*
142
which of the following **tisssue types** is most likely to **source** of **cementogenic cells** in adults who have **undergone root planning**?
a. bone marrow
b. periodontal ligament
c. residual cementum patches
d. alveolar process
b. **periodontal ligament**
* The **periodontal ligament** has a **line** of **cementoblasts** along the **cemental surface** of the **root** that can **produce cementum** **throughout the lifetime of the tooth.***
143
Which of the following tissue types **covers and lines** *both* the **external and internal body surfaces**?
a. Adipose
b. Connective tissue
c. Cartilage
d. Epithelium
d. **Epithelium**
144
Which of the following tissue types **provides nutrition** for the underlying **compact bone**?
a. Cartilage
b. Periosteum
c. Compact bone
d. Cancellous bone
b. **Periosteum**
145
which of the following types of **dental tissue** provides **vascular nutrition** for the tooth's **cementum**?
a. dentin
b. epithelial cells
c. periodontal ligament
d. alveolar process
c. **periodontal ligament**
T*he canals of the **cementocytes** are oriented **toward** the **periodontal ligament** and contain **cementocytic processes** that exist to **diffuse nutrients** from the **ligament** because it is **vascularized.***
146
Which of the following **zones** in **pulp** is **closest** to the **dentin**?
a. odontoblastic layer
b. cell-rich zone
c. pulpal core
d. cell-free zone
a. **odontoblastic layer**
* The **first zone** of pulp **closest to the dentin** is the **odontoblastic layer**. The next zone, **nearest to the odontoblastic laye**r, **inward from the dentin**, is considered the **cell-free zone**. The **final zone** of pulp is the **pulpal core**, which is in the **center** of the **pulp chamber.***
147
which of these **fiber groups** does **_not_** have any **cemental insertion**?
a. interdental ligament
b. circular ligament
c. alveodental ligament
d. Interradicular group
b. **circular ligament**
* The **circular ligament encircles the tooth,** as shown on a **cross-section** of a tooth, **interlacing with the other gingival fiber subgroups**. Thus, it has **no cemental insertion.** The interdental ligament and **alveodental ligament**, which the **interradicular group** is part of on **multirooted teeth**, both have **cemental insertions.***
148
**which part** of **both** of the **jaws** contains **cancellous bone**?
a. alveolar bone proper
b. cortical bone
c. interdental septum
d. alveolar crest
c. **interdental septum**
* The **interdental septum** consists of both the **compact bone** of the **alveolar bone proper** and **cancellous bone** of the **trabecular bone**. The **cortical bone** consists of a **plate of compact bone** on both the **facial and lingual surfaces** of the **alveolar process.** The **alveolar crest** is the **most cervical rim of the alveolar bone proper.***
149
which part of the **periodontal ligament** is noted to be **wider** in a **healthy adult tooth**?
a. near the apex
b. near the cervix
c. both near the apex and cervix
d. between the apex and cervix
c. **both** near the **apex** and **cervix**
* The **periodontal ligament is wider near** the **apex and cervix of the tooth** and **narrower** between these **two endpoints.***
150
Which part of the **tooth germ** is the primary source for the **periodontal ligament (PDL)** of the tooth?
a. Dental sac
b. Hertwig epithelial root sheath
c. Stratum intermedium
d. Central cells of dental papilla
a. **Dental sac**
**Mesoderm → Dental sac = PDL, cemuntum and some alvelor bone**
151
Which **permanent teeth** undergo **partial** **anodontia** the *most* within the developing oral cavity?
a. Third molars
b. Mandibular second premolars
c. Maxillary lateral incisors
d. Maxillary first premolars
a. **Third molars**
***Anodontia**- the lack of initiation within the **dental lamina** results in the **absence** of a **single tooth** or **multiple teeth (partial)** or an entire dentition (complete),*
152
Which specific muscle can become **clinically enlarged** in patients who **habitually clench or grind** (with bruxism) their teeth and in those who **constantly chew gum**?
a. Masseter muscle
b. Lateral pterygoid muscle
c. Medial pterygoid muscle
d. Temporalis muscle
a. **Masseter muscle**
153
Which stage of tooth formation occurs for the primary dentition during the **eleventh and twelfth week** of prenatal development?
a. Bell stage
b. Initiation stage
c. Cap stage
d. Bud stage
a. **Bell stage**
Initiation stage (6-7th week)
Bud stage (8th)
Cap stage (9-10th week)
Bell stage (11-12th week)
154
Which teeth are associated with the further development of the
**primary palate**?
a. Maxillary incisors
b. Mandibular incisors
c. Maxillary canines
d. Mandibular posterior teeth
a.
## Footnote
**Maxillary incisors**
155
Which type of **blood cell** is *directly* responsible for **immunoglobulin** **production**?
a. Neutrophils
b. Basophils
c. Plasma cells
d. Mast cells
c. **Plasma cells**
**lymphocytes = plasma cells**
156
which type of **bone** is **only present** in an area of **anodontia**?
a. cortical bone
b. basal bone
c. alveolar bone proper
d. trabecular bone
b. **basal bone**
* The developmental dental anomaly of anodontia, in which **tooth germs** are **congenitally absent**, may affect the development of the alveolar process of either jaw. Proper development is impossible because the alveolar unit of each dental arch only forms in response to the tooth germs in the area. **Only basal bone** will be **present in each one** of the **involved areas of the jaws.** The alveolar process, which includes the **alveolar bone proper and the supporting alveolar bone**, the latter of which consists of the **cortical bone and trabecular bone, will not have developed due to the anodontia.***
157
Which **zone** in the **pulp** contains a **nerve and capillary plexus**?
a. odontoblastic layer
b. cell-rich zone
c. pulpal core
d. cell-free zone
b. **cell-rich zone**
* A nerve and capillary plexus are also located in the cell-free zone of the pulp. The odontoblastic zone consists of a layer of odontoblasts. The **cell-rich zone** has an **increased density of cells compared with the cell-free zone but still does not contain as many cells as the odontoblastic laye**r. This zone also has a more extensive vascular supply than does the cell-free zone. The pulpal core, which is in the center of the pulp chamber, consists of many cells and an extensive vascular supply; except for its location, it is very similar to the cell-rich zone.*
158
with **occlusal trauma**, there can be a **widening** of the:
a. periodontal space
b. periodontal ligament
c. lamina dura
d. periodontal space, periodontal ligament, and lamina dura
d. **periodontal space, periodontal ligament, and lamina dura**
***Early occlusal trauma** can be viewed on radiographs as a **widening of the radiolucent (or darker) periodontal ligament space** between the radiopaque (or lighter) lamina dura of the alveolar bone proper and the similar radiopaque (or lighter) cementum. Because the periodontal space represents the periodontal ligament, the ligament can double and the individual principal fiber bundles also become thicker. **Thickening of the lamina dura,** which represents the **alveolar bone proper, is also possible with occlusal trauma in response to overall alveolar process loss.***
159
Within **fully mineralized bone** are **osteocytes**, which are **entrapped mature** **_osteoclasts_**.
**Osteoblasts** never undergo **mitosis** during tissue formation, and thus **only one** **osteocyte** is ever found in a **lacuna.**
The **first** statement is **false**
the **second** statement is **true.**
160
\_\_\_\_\_\_; the function of this membrane is to **shape the root.**
(A) Cervical Loop
(B) Hertwig Epithelial Root Sheath
(C) Cementocytes
(D) Cementogenesis
**Hertwig Epithelial Root Sheath (HERS)**
161
\_\_\_\_\_\_\_\_\_ ________ is the main part of the **anterior border of ramus** that forms a **concave forward curve**
**Coronoid notch**
162
**What condition** develops from the **neural tube failing to fuse properly**, characterized by **defects** in the **vertebral arches** and **various degrees of disability**?
**Spina Bifida**
