ORPTH ADONS DEV ANOMALIES, n DENT CARZ Flashcards

1
Q
  1. Which amongst the following is not a cause of acquired
    micrognathia?
    (a) Infection of mastoid
    (b) Trauma to TMJ
    (c) Infection of the middle ear
    (d) Infection of inner ear
A

(d) Acquired micrognathia is of postnatal origin and results
usually from disturbance in the area of the temporomandibular
joint like infection of mastoid, middle ear or
joint itself.

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2
Q
  1. Which amongst the following is not a clinical feature of
    micrognathia?
    (a) Steep mandibular angle
    (b) Severe retrusion of chin
    (c) Prominent chin button
    (d) Deficient chin button
A

(c) Micrognathia is characterized by severe retrusion of chin,
steep mandibular angle and a deficient chin button.

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3
Q
  1. Indicate the incorrect statement regarding macrognathia
    (a) It is commonly associated with Paget’s disease
    (b) Patients tend to have a short ramus
    (c) Excessive condylar growth predisposes to macrognathia
    (d) Patients have a prominent chin button
A

(b) Macrognathia may be associated with other diseases like
Paget’s disease, fibrous dysplasia, acromegaly, etc. and
shows features like increased ramus height and length of
6 MCQs in Oral Pathology
mandibular body, decreased maxillary length, prominent
chin button increased gonial angle, etc.

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4
Q
  1. Facial hemiatrophy is not associated with which of the following
    conditions?
    (a) Bell’s palsy (b) Trigeminal neuralgia
    (c) Jacksonian epilepsy (d) Delayed eruption of teeth
A

(a) Progressive hemifacial atrophy is an uncommon,
degenerative condition characterized by atrophic changes
affecting one side of the face. Possible causes include trophic
malfunction of the cervical lymphatic nervous system,
trauma and viral or Borrelia infection.

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5
Q
  1. Cleft of the primary palate occurs
    (a) Anterior to incisive foramen
    (b) Posterior to incisive foramen
    (c) Between lateral incisor and canine
    (d) Between canine and 1st premolar
A

(a) A complete cleft palate includes cleft of hard palate, soft
palate and uvula. Cleft anterior to the incisive foramen is
called cleft of primary palate, while cleft posterior to incisive
foramen is defined as cleft of secondary palate

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6
Q
  1. Minimal form of clefting of palate is seen in
    (a) Soft palate
    (b) Uvula
    (c) Hard palate and soft palate
    (d) Posterior to incisive foramen
A

(b) Clefting occurs in a wide range of severity. Clefting of uvula
is the minimal form of cleft.

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7
Q
  1. Increased risk of development of squamous cell carcinoma
    is associated with which of the following developmental
    conditions?
    (a) Cheilitis granulomatosa
    (b) Heck’s disease
    (c) Cheilitis glandularis
    (d) Fibromatosis gingivae
A

(c) It is an unusual clinical presentation of cheilitis that develops
in response to various sources of chronic irritation. There
is progressive enlargement and eversion of lower lip that
significantly exposes it to actinic damage which may be a
potential predisposing factor to development of squamous
cell carcinoma.

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8
Q
  1. If a patient has multiple intestinal polyps, cutaneous melanocytic
    macules, rectal prolapse and gynecomastia, he/she is probably
    suffering from
    (a) Gardner syndrome
    (b) Goltz-Gorlin syndrome
    (c) Peutz-Jeghers syndrome
    (d) Grinspan syndrome
A

(c) It is an autosomal dominant, inherited disorder characterized
by multiple intestinal polyps and concomitant
mucocutaneous melanocytic macules

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9
Q
  1. Fordyce’s granules is heterotopic collection of _______ in oral
    cavity
    (a) Sweat glands (b) Salivary glands
    (c) Hair follicles (d) Sebaceous glands
A

(d) Occurrence of sebaceous glands in oral cavity may result
from inclusion in oral cavity, of ectoderm having some of
the potentialities of skin.

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10
Q
  1. Heck’s disease is caused by ________ virus
    (a) Herpes simplex (b) Human papilloma
    (c) Varicella zoster (d) Epstein-Barr
A

(b) It is caused by human papillomavirus HPV-13 and probably
HPV-32. It is different from other HPV lesions in that it
produces extreme acanthosis and hyperplasia of stratum
spinosum with minimal surface projection or connective
tissue proliferation

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11
Q
  1. A well-circumscribed, soft, sessile, bilateral, nodular mass which
    is located lingual to mandibular canines between mucogingival
    junction and free gingiva could most likely be
    (a) Peripheral giant cell granuloma
    (b) Pyogenic granuloma
    (c) Retrocuspid papilla
    (d) Peripheral ossifying fibroma
A

(c) Retrocuspid papilla is a developmental lesion microscopically
similar to giant cell fibroma. It occurs on the
gingiva lingual to the mandibular cuspid, is frequently
bilateral and typically appears as a small, pink papule that
measures less than 5 mm in diameter.

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12
Q
  1. Which amongst the following is not a cause of macroglossia?
    (a) Hemangioma (b) Lymphangioma
    (c) Down’s syndrome (d) Leukemia
A

(d) It is an uncommon condition characterized by enlargement
of the tongue. The enlargement may be caused by
a wide variety of conditions including both congenital
malformations and acquired diseases. The most frequent
causes are vascular malformations and muscular
hypertrophy.

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13
Q
  1. Which one of the following is a synonym of fissured tongue?
    (a) Lingua nigra (b) Scrotal tongue
    (c) Geographic tongue (d) Lingual varix
A

(b) Scrotal/fissured tongue is a common condition characterized
by presence of numerous grooves on dorsal surface of
tongue. Cause is uncertain but may be heredity. Aging and
local environmental factors may also play some role.

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14
Q
  1. Median rhomboid glossitis occurs
    (a) Anterior to circumvallate papillae
    (b) Posterior to circumvallate papillae
    (c) Tip of tongue
    (d) Lateral border of tongue
A

(a) Clinically median rhomboid glossitis appears as a welldemarcated
erythematous zone that affects the midline,
posterior dorsal tongue and often is asymptomatic

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15
Q
  1. Histopathological features of benign migratory glossitis closely
    resemble that of
    (a) Lichen planus
    (b) Psoriasis
    (c) Systemic lupus erythematosus
    (d) Erythema multiforme
A

(b) Hyperparakeratosis, spongiosis, acanthosis, elongation of
epithelial rete ridges and collections of neutrophils (Munro
abscesses) are also seen in psoriasis.

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16
Q
  1. Amongst the following causes, the least probable cause of hairy
    tongue is
    (a) Smoking (b) Poor oral hygiene
    (c) Epstein-Barr virus (d) Radiation therapy
A

(c) Epstein-Barr virus is responsible for causing hairy
leukoplakia which occurs on the lateral surfaces of tongue
and is associated with HIV or other immunosuppressive
conditions.

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17
Q
  1. A nodular mass near base of tongue with presenting complaints
    of dyspnea and dysphagia and without a demonstrable
    main
    thyroid gland could most probably be
    (a) Reactive lymphoid aggregate
    (b) Lymphoid hamartoma
    (c) Lingual thyroid nodule
    (d) Lymphoepithelial cyst
A

(c) Lingual thyroids may range from small, asymptomatic
nodular lesions to large masses that can block the airway.
The most common clinical symptoms are dysphagia,
dysphonia, and dyspnea. Diagnosis is best established by
thyroid scan using technetium 99m

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18
Q
  1. Stafne cyst/Stafne defect is an aberrant collection of _____ gland
    tissue within a deep depression in the mandible
    (a) Sweat glands (b) Sebaceous glands
    (c) Mucous glands (d) Salivary glands
A

(d) Stafne defect presents as an asymptomatic radiolucency
below the mandibular canal in the posterior mandible,
between the molar teeth and the angle of the mandible.

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19
Q
  1. Apart from maxillary lateral incisor, which other tooth is
    commonly affected by microdontia?
    (a) Mandibular premolars
    (b) Maxillary canines
    (c) Mandibular central incisors
    (d) Third molars
A

(d) Isolated microdontia within an otherwise normal dentition
is not uncommon. The maxillary lateral incisor is affected
most frequently, followed by third molars.

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20
Q
  1. Fusion of teeth involves a confluence of
    (a) Enamel only (b) Enamel and dentin
    (c) Dentin only (d) Cementum only
A

(b) Fusion is defined as a single-enlarged tooth or joined (i.e.
double) tooth in which the tooth count reveals a missing
tooth when the anomalous tooth is counted as one.

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20
Q
  1. In association with which syndrome does talon cusp usually
    occur?
    (a) Rubinstein-Taybi
    (b) Down
    (c) Hereditary ectodermal dysplasia
    (d) Gardner
A

(a) A talon cusp (dens evaginatus of anterior tooth) is a welldelineated
additional cusp that is located on the surface of
an anterior tooth and extends at least half the distance from
the cementoenamel junction to the incisal edge

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20
Q
  1. Dilated odontome is a synonym of
    (a) Dens invaginatus (b) Talon cusp
    (c) Dens evaginatus (d) Macrodontia
A

(a) Dens invaginatus is a deep surface invagination of the crown
or root that is lined by enamel. Two forms—coronal and
radicular are recognized

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20
Q
  1. With which variation in coronal morphology is dens evaginatus
    associated?
    (a) Peg-shaped laterals (b) Shovel-shaped incisors
    (c) Dilaceration (d) Distomolar
A

(b) Dens evaginatus is a cusp-like elevation of enamel located
in the central groove or lingual ridge of the buccal cusp
of permanent premolar or molar teeth. Frequently, dens
evaginatus is seen in association with another variation of
coronal anatomy, shovel-shaped incisors. Affected incisors
demonstrate prominent lateral margins, creating a hollowed
lingual surface that resembles the scoop of a shovel.

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20
Q
  1. The base of invagination of crown/root in dens invaginates
    contains
    (a) Dystrophic dentin (b) Dystrophic enamel
    (c) Necrotic pulp tissue (d) Dystrophic cementum
A

(b) Coronal dens invaginatus has been classified into three
major types. Type I exhibits an invagination that is limited
to the crown. The invagination in Type II extends below the
cementoenamel junction and ends in a blind sac that may
or may not communicate with adjacent dental pulp. Large
invaginations may become dilated and contain dystrophic
enamel in the base of the dilatation. Type III extends through
the root and perforates in the apical or lateral radicular area
without any immediate communication with the pulp.

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21
Q
  1. Which bone disorder should be considered for differential
    diagnosis in case of a finding of generalized hypercementosis?
    (a) Paget’s disease (b) Fibrous dysplasia
    (c) Osteopetrosis (d) Osteogenesis imperfecta
A

(a) Paget’s disease of bone is characterized by abnormal
and anarchic resorption and deposition of bone and
on radiographic examination, the teeth very commonly
demonstrate extensive hypercementosis.

21
Q
  1. If a patient shows signs of kinky hair, osteosclerosis at base of
    skull, brittle nails along with hypomaturation—hypoplastic
    amelogenesis imperfecta, he/she is most probably suffering
    from
    (a) Rubinstein-Taybi syndrome
    (b) Klinefelter syndrome
    (c) Cranioectodermal syndrome
    (d) Tricho-dento-osseous syndrome
A

(d) It is an autosomal dominant disorder in which hypomaturation
as well as hypoplastic patterns of amelogenesis
imperfecta are seen.

22
Q
  1. The appearance of normal thickness enamel with extremely thin
    dentin and abnormally large pulp chamber is indicative of
    (a) Amelogenesis imperfecta
    (b) Dentinogenesis imperfecta Type I
    (c) Dentinogenesis Type III
    (d) Dentin dysplasia Type II
A

(c) Dentinogenesis imperfecta is a hereditary developmental
disturbance of the dentin in the absence of any systemic
disorder. Type III dentinogenesis imperfecta, also called
Brandywine isolate is characterized by isolated opalescent
teeth. The appearance of normal thickness enamel in
association with extremely thin dentin and dramatically
enlarged pulps is called shell teeth.

23
Q

All of the below given factors are responsible for causing dental
caries except
(a) Dental plaque (b) Diet
(c) Microorganisms (d) Temperature

A

d) Initiation and progression of dental caries is dependent
upon following factors: substrate (carbohydrate), bacteria,
acid and dental plaque.

23
Q

Which of these factors has not been assigned an essential role in
Miller’s chemicoparasitic theory of dental caries?
(a) Carbohydrates (b) Microorganisms
(c) Heredity (d) Acids

A

(c) Miller assigned essential roles to carbohydrate substrate,
acids and microorganisms in causing dental caries. Factors
like heredity did not find mention in his theory. In fact one of
the objections to Miller’s hypothesis is the inability to explain
site and racial predilection.

23
Q
  1. Loss of organization of radicular dentin with subsequent
    shortening of root length is a feature of
    (a) Dentin dysplasia Type I
    (b) Dentin dysplasia Type II
    (c) Dentinogenesis imperfecta Type II
    (d) Dentinogenesis imperfecta Type III
A
  1. (a) This autosomal dominant disorder is also called rootless
    teeth because of the loss of organization of the root dentin
    which often leads to a shortened root length.
23
Q
  1. Which amongst the following diseases is capable of producing
    developmental alterations in teeth?
    (a) Tetanus (b) Chickenpox
    (c) Diphtheria (d) Syphilis
A

(d) Congenital syphilis alters the formation of both the anterior
teeth (Hutchinson’s incisors) and the posterior teeth
(Mulberry molars).

23
Q

According to miller, which of these acids was held responsible for
producing the lesions of dental caries, according to Miller?
(a) Lactic acid (b) Ascorbic acid
(c) Picric acid (d) Citric acid

A

(a) WD Miller, in his experiment, incubated a mixture of
meat, bread and sugar with saliva at body temperature. It
produced enough lactic acid within 48 hours to decalcify
sound dentin.

23
Q

From the properties given below identify which one does render
carbohydrates cariogenic?
(a) Rapid clearance from oral cavity
(b) Stickiness of carbohydrates
(c) Frequent ingestion of carbohydrates
(d) Simple carbohydrates

A

(a) Carbohydrates that are cleared rapidly from oral cavity
are considered less cariogenic as they remain for a lesser
duration inside the oral cavity to be fermented by cariogenic
bacteria.

23
Q
  1. Lack of development of six or more teeth is denoted by the term
    (a) Oligodontia (b) Hypodontia
    (c) Anodontia (d) Partial anodontia
A
  1. (a) It is an autosomal dominant disorder with incomplete
    penetrance. Congenitally absent teeth are one of the most
    common dental developmental anomalies with third molars
    and maxillary lateral incisors being the most commonly
    developmentally missing teeth.
24
Q

Which inorganic constituent is present in highest concentration
in dental plaque?
(a) Phosphorus (b) Calcium
(c) Iron (d) Fluorine

A

(b) Dry weight of plaque is composed of
Bacterial and salivary proteins—50 percent
Carbohydrates and lipids—25 percent
Inorganic ions, mainly Ca++ and PO4
– —10 percent

24
Q

Identify which amongst the below given bacteria does not cause
dental caries.
(a) S. mutans (b) L. acidophilus
(c) A. naeslundii (d) S. aureus

A

(d) While other three bacteria have been implicated in causation
of dental caries, evidence for involvement of S. aureus in
causing dental caries is lacking

24
Q

Dental plaque contains all of the following, except
(a) Microorganisms
(b) Mucin
(c) Exudate
(d) Desquamated epithelial cells

A

(c) Dental plaque is a soft, nonmineralized biofilm composed
of bacteria, salivary proteins, lipids, carbohydrates and
inorganic ions mainly, calcium and phosphate

25
Q

Which product of the streptococci is responsible for adherence
of the dental plaque to the smooth surfaces of teeth?
(a) Glucan (b) Glycoprotein
(c) Glycosaminoglycan (d) Proteoglycan

A

(a) Highly acidogenic strains of streptococci like S. mutans
have the ability to metabolize dietary sucrose and synthesize glucan by cell surface and extracellular enzyme
glucosyltransferase

26
Q

Which is the principal buffering ion present in saliva?
(a) Bismuth (b) Bicarbonate
(c) Phosphorus (d) Fluoride

A

(b) Although bicarbonate is the principal buffering ion present
in saliva, another ion, phosphate is also associated with
this function. They aid in maintaining a high pH of saliva,
because at pH below 5.5, enamel begins to dissolve

27
Q

Which amongst the following factors does not contribute towards
greater caries resistance of the surface enamel of a tooth?
(a) Fluoride content (b) Slower dissolution in acids
(c) Lesser water content (d) Lesser mineral content

A

(d) Surface enamel is more heavily mineralized compared
to subsurface enamel. Because of the increased mineral
content, surface enamel is able to resist demineralization
better.

28
Q

The tooth that is most susceptible to dental caries is
(a) Mandibular 1st molars (b) Mandibular 2nd molars
(c) Maxillary canines (d) Maxillary 2nd premolars

A

(a) Permanent mandibular first molars are the most susceptible
teeth to dental caries for primarily for two reasons—they are
the first permanent teeth to erupt and their occlusal surfaces
have more and deeper pits and fissures

29
Q

State which amongst the below given factors is not an antibatcerial
factor present in saliva.
(a) Lysozyme (b) Lysosome
(c) Lactoferrin (d) SIGA

A

(b) Saliva contains many antibacterial substances like
lactoferrin, lysozymes, carbonic anhydrase, bistatin, sIgA,
etc.

30
Q

The factor that is least associated with increased incidence of
dental caries is
(a) Carbohydrate rich diet (b) Malposed tooth
(c) Smoking (d) Quantity of saliva

A

(c) Carbohydrate rich diet, malposed teeth and insufficient or
no saliva are amongst the principal contributory factors of
dental caries, while smoking has a much lesser role to play
in causing caries.

31
Q

Undermining of enamel occurs due to
(a) Lateral spread of caries midway between enamel and dentin
(b) Lateral spread of caries at the dentinoenamel junction
(c) Lateral spread of caries midway between dentin and pulp
(d) Spread of caries along dentinal tubules

A

(b) When the caries process reaches dentinoenamel junction
there is rapid lateral spread of dental caries which causes the
undermining of enamel due to the presence of unsupported
enamel rods above the DEJ.

32
Q

The least likely location for occurrence of smooth surface caries
is:
(a) Labial surface of maxillary incisors
(b) Proximal surfaces of all teeth
(c) Gingival 1/3rd of buccal surfaces of teeth
(d) Gingival 1/3rd of lingual surfaces of teeth

A

(a) The labial surfaces of maxillary incisors being self-cleansing
areas, they are the least likely location for occurrence of
dental caries.

33
Q

A caries increment of __ or more new carious lesions over one
year is considered characteristic of rampant caries
(a) 8 (b) 5
(c) 10 (d) 15

A

(c) Rampant dental caries is characterized by sudden, rapid
destruction of teeth affecting even relatively caries-free
surfaces like proximal and cervical surfaces of mandibular
teeth.

33
Q

Which theory of dental caries proposes that organic elements in
teeth are the initial pathway of invasion of microorganisms?
(a) Sucrose chelation (b) Proteolytic
(c) Autoimmune (d) Chemicoparasitic

A

(b) Gottlieb, Diamond and Appelbaum postulated that the
organic elements like enamel lamellae, rod sheath, etc. are
the initial pathway of invasion by cariogenic organisms

34
Q

Acute dental caries occurs most frequently in children and young
adults because
(a) Dentinal tubules are scleroses in the teeth of young people
(b) The apex of root of teeth are not formed completely
(c) Dentinal tubules are narrower in diameter
(d) Dentinal tubules are larger, open and show no sclerosis

A

(d) Dentin of children and young adults is characterized by
larger, more open dentinal tubules with no sclerosis. Also
there is very little secondary dentin formation due to the
rapid spread of acute caries.

35
Q

Nursing bottle caries is a type of _______ caries
(a) Acute (b) Recurrent
(c) Rampant (d) Arrested

A

(c) Nursing bottle caries is a form of rampant caries clinically
seen as widespread caries of the 4 maxillary incisors
followed by 1st molars and then canines. Usually it is
caused by use of sweetened pacifiers and nursing bottle
containing sweetened milk or milk formula and also due
to continuation of breastfeeding beyond one year of age.

36
Q

Absence of caries in _______ teeth helps to distinguish nursing
bottle caries from rampant caries
(a) Maxillary canines (b) Mandibular incisors
(c) Maxillary incisors (d) Mandibular canines

A

(b) Nursing bottle caries is usually caused by pooling of milk or
other carbohydrates in mouth. Mandibular incisors escape
this process as the pooled milk/carbohydrate is cleared away
by saliva.

37
Q

Which type of caries is most likely to show considerable surface
destruction, shallow cavity, little undermining of enamel and
little or no pain?
(a) Chronic (b) Acute
(c) Rampant (d) Recurrent

A

(a) In comparison with acute caries there is lesser surface
destruction with a shallower cavity and little or no
undermining of enamel in chronic caries. Also due to slow
progress of caries, there is sufficient time for formation of
tertiary dentin which provides some protection of pulp,
thereby leading to lesser or no pain.

38
Q

The first change to occur in caries of enamel is
(a) Loss of rod enamel
(b) Loss of inter rod enamel
(c) Loss of rod sheath
(d) Increased prominence of enamel rods

A

(b) When enamel begins to demineralize the earliest electron
microscopic changes are loss of inter rod enamel and
accentuation of striae of Retzius

39
Q

Which surface of a tooth has maximum susceptibility for
occurrence of dental caries?
(a) Occlusal (b) Lingual
(c) Mesial (d) Distal

A

(a) Occlusal surface is the most susceptible surface for
occurrence of dental caries to retaining centers on this
surface in the form of pits and fissures.

40
Q

In enamel caries, the advancing front of the lesion is called
(a) Body of lesion (b) Dark zone
(c) Surface zone (d) Translucent zone

A

(d) Translucent zone lies at the advancing front of dental caries
lesion and is slightly more porous than normal enamel.

41
Q

Of all the zones in enamel caries which zone is not always
present?
(a) Translucent (b) Dark
(c) Body (d) Surface

A

(a) Translucent zone occurs due to formation of submicroscopic
pores at enamel rod boundaries and striae of Retzius. It
cannot be seen clinically or radiologically and is thus also
called negative zone sometimes.

42
Q

The most accepted theory on mechanism of action of ingested
fluoride is
(a) Absorption of fluoride ions on hydroxyapatite crystallites
(b) Prevention of carbohydrate degradation
(c) Inhibition of microorganisms
(d) Incorporation of fluoride in crystal structure of enamel

A

(d) Water fluoridation has been shown to be the most effective
method of caries control in large community. The most
accepted hypothesis for this is that the systemically absorbed
fluoride replaces the hydroxyl ion in hydroxyapatite crystal,
forming fluorapatite which is less soluble in acids.

42
Q

What is the earliest histological evidence of dentinal caries?
(a) Transparent dentin
(b) Fatty degeneration of odontoblastic processes
(c) Lateral spread of caries along dentino-enamel junction
(d) Miller’s liquefaction foci

A

(b) The earliest histological evidence of dentinal caries is fatty
degeneration of tome’s dentinal (odontoblastic) processes
and deposition of fat globules in these processes.

43
Q

The most commonly employed fluoride in dentifrices is
(a) Sodium monofluorophosphate
(b) Stannous fluoride
(c) Acidulated phosphate fluoride
(d) Sodium fluoride

A

(d) Sodium fluoride is most commonly employed in
toothpastes, mouth rinses and gels. Typically these are low
fluoride concentration products ranging from 200–1000
ppm or 0.2–1 mgF/mL

44
Q

What is the percentage of fluoride in acidulated phosphate
fluoride (APF) gels?
(a) 2.34 percent (b) 1.23 percent
(c) 3.45 percent (d) 1.24 percent

A

(b) An aqueous solution of acidulated phosphate fluoride
is prepared by dissolving 20 grams of sodium fluoride in
1 liter of 0.1 M phosphoric acid and to this is added 50% hydrofluoric acid to adjust the pH at 3.0 and fluoride ion
concentration at 1.23%. It is also called as Brudevold’s
solution.

45
Q

The mechanism of cariostatic action of chlorhexidine is
(a) Absorption into enamel crystals
(b) Absorption into enamel crystals and salivary mucins
(c) Inhibition of microorganisms
(d) Inhibition of carbohydrate degradation

A

(b) Chlorhexidine has been shown to have an immediate
bactericidal action and a prolonged bacteriostatic action
due to adsorption onto the pellicle-coated enamel surface