Regressive changes of OC Flashcards
- Which of the following surfaces do not show attrition?
(a) Occlusal
(b) Proximal
(c) Gingival 1/3rd
(d) Incisal
(c) Attrition is defined as mechanical wear and tear of tooth
substance as a result of tooth-to-tooth contact, as happens
in case of mastication. While occlusal, incisal and proximal
surfaces do come in contact during mastication, the gingival
1/3rd regions of teeth do not do so.
- The exposure of dentinal tubules and resultant irritation of
odontoblastic processes leads to formation of
(a) Polished facet on tooth surface affected by attrition
(b) Sclerotic dentin
(c) Tertiary dentin
(d) Predentin
(c) Tertiary dentin, also known as reparative secondary dentin
is formed around the pulp chamber in response to irritation
of odontoblasts.
- All except _______________ are common causes of attrition.
(a) Abrasive dentifrices
(b) Habitual biting of bobby pins
(c) Improper use of toothpicks and dental floss
(d) Vertical toothbrushing habit
(d) Although modern dentifrices are not abrasive enough to
cause abrasion, the toothbrush carrying the dentifrice can
cause remarkable wear and tear of enamel and cementum,
especially with horizontal technique of brushing.
- Erosion is defined as irreversible loss of tooth substance by a
chemical process that does not involve
(a) Bacteria (b) Virus
(c) Saliva (d) Tissue fluid
(a) Loss of tooth substance owing to a chemical process
involving bacteria is called Dental Caries
- All of the following except _____ are etiological factors of erosion.
(a) Faulty toothbrushing habit
(b) Acidic beverages
(c) Medications
(d) Regurgitated gastric acid
(a) Improper brushing technique leads to the formation of a
V-shaped facet on the tooth. This process is called abrasion
and does not involve any chemical process, unlike erosion
- Chronic excessive vomiting has long been recognized as a cause
of
(a) Abrasion
(b) Abfraction
(c) Attrition
(d) Erosion
(d) Patients suffering from anorexia nervosa or bulimia usually
but not always manifest erosion on the palatal surfaces of
maxillary teeth. Such patients are also known to consume
large quantities of acidic beverages, which can affect labial
surfaces of teeth also.
- Sclerosis of primary dentin is characterized by _____ of dentinal
tubules.
(a) Exposure
(b) Calcification
(c) Loss
(d) Wearing away
(b) Dentinal sclerosis results not only from injury to dentin, but
is also a manifestation of normal aging process, just like the
continuous deposition of physiological secondary dentin
around the pulp chamber.
- The dentin that is laid down around the pulp chamber as a result
of a normal aging process is referred to as
(a) Tertiary dentin
(b) Interglobular dentin
(c) Intertubular dentin
(d) Physiologic secondary dentin
(d) Physiologic secondary dentin is an age-related phenomenon
and begins as soon as the tooth erupts into the oral cavity.
Due to this, the volume of pulp chamber gradually decreases
as age advances.
- Which one of the following statements is incorrect regarding
tertiary/reparative secondary dentin?
(a) It is an age-related phenomenon
(b) It forms as a result of irritation of odontoblasts
(c) Affected teeth show markedly reduced sensitivity
(d) Number of dentinal tubules per unit area is less and more
irregularly arranged compared to primary dentin
(a) Tertiary dentin formation is essentially a pathologic process
and is initiated by irritation to the odontoblasts as in cases
of dental caries, improper cavity cutting procedure, etc.
- Reticular atrophy of pulp is characterized by
(a) Dilated blood vessels
(b) Increased calcific deposits
(c) Presence of large, vacuolated spaces
(d) Infiltration of large number of lymphocytes
(c) Reticular atrophy of pulp is a regressive change and is seen in
elderly persons. Histologically it is seen as large vacuolated
spaces in pulp along with a reduction in cellular elements
of pulp.
- The principal cause of internal resorption of teeth is
(a) Inflammatory hyperplasia of pulp
(b) Vacuolar degeneration of pulp
(c) Pulp calcification inside pulp chamber
(d) Periapical inflammation
(a) Pink tooth of mummery (internal resorption) is associated
very commonly with a peculiar inflammatory hyperplasia of
pulp, whose cause is unknown. However, carious exposure
and accompanying pulp inflammation are sometimes
present.
- External resorption of roots is not caused by which one amongst
the following factors?
(a) Impaction of teeth
(b) Consumption of acidic beverages
(c) Periapical inflammation
(d) Tumors and cysts around roots
(b) External resorption of roots can occur due to various
factors that bring about forces to act on the roots as in case
of impaction or presence of tumors/cysts and also due to
osteoclastic resorption as in case of periapical inflammation.
- The nodules of true denticles bear a great resemblance to
(a) Intratubular dentin
(b) Predentin
(c) Secondary dentin
(d) Intertubular dentin
(c) True denticles contain, few and irregularly arranged dentinal
tubules, thus they resemble secondary dentin more than
primary dentin.
- Identify the disorders amongst the below given that is commonly
associated with generalized hypercementosis.
(a) Fibrous dysplasia
(b) Cherubism
(c) Osteitis deformans
(d) Osteopetrosis
(c) Osteitis deformans or Paget’s disease of bone is a generalized
disorder of bones characterized by deposition of excessive
amounts of secondary cementum overroots of teeth. Thus
presence of generalized hypercementosis should always
suggest the possibility of Paget’s disease.
- Which one of the following conditions does not produce any
signs/symptoms like increase or decrease of tooth sensitivity,
tenderness to percussion, etc.?
(a) Secondary dentin
(b) Periapical granuloma
(c) Periapical abscess
(d) Hypercementosis
(d) Hypercementosis does not manifest any outward signs/
symptoms unless periapical inflammation is present along
with it
- The condition that is most likely to initiate hyperplasia of
cementum is:
(a) Osteomyelitis
(b) Elongation of a tooth due to loss of its antagonist
(c) Extreme orthodontic force application
(d) Impaction
(b) Elongation of tooth due to loss of its antagonist is often
followed by hyperplasia of cementum mainly as a result
of the inherent tendency to maintain normal periodontal
width.
- The hypercementosis that occurs following loss of an opposing
tooth usually occurs on
(a) Cervical 1/3rd of root
(b) Entire root surface
(c) Apical 1/3rd of root
(d) Middle 1/3rd of root
(c) The hypercementosis in such cases is most obvious at
the apical 1/3rd region of root and tapers off in thickness
towards cervical 1/3rd.
- Diagnosis of hypercementosis is established radiologically by
(a) Detecting differences in radiodensity between tooth
structures
(b) Loss of lamina dura around roots
(c) Widening of periodontal space around the roots
(d) Detection of blunted root apex
(d) It is impossible radiologically to differentiate between
primary and secondary cementum. Therefore, change in
shape or outline of root apex is the only means of diagnosing
hypercementosis on a radiograph.
- Hypercementosis is characterized histologically by deposition
of
(a) Primary acellular cementum over secondary cellular
cementum
(b) Secondary cellular cementum over primary acellular
cementum
(c) Secondary cellular cementum over radicular dentin
(d) Primary acellular cementum over radicular dentin
(b) The histological appearance of hypercementosis is typical
and is seen as deposition of excessive amounts of secondary
cellular cementum over a thin layer of primary acellular
cementum
- The secondary cellular cementum that is laid down in hypercementosis is also referred to as
(a) Osteocementum
(b) Osteodentin
(c) Tertiary cementum
(d) Reparative cementum
(a) The secondary cellular cementum laid down in hypercementosis is also called osteocementum due to its high
cellularity and histological resemblance to bone, just like
osteodentin in cases of tertiary dentin deposition.
- Cementicles are considered to represent areas of
(a) Dystrophic calcification
(b) Metastatic calcification
(c) Ectopic calcification
(d) Dysplastic calcification
(a) The most common way in which cementicles form is
dystrophic calcification in the cell rests of Malassez located
in the periodontal ligament, as a result of degenerative
change.
- Odontoclastoma is another name for
(a) Cementicles
(b) External resorption of tooth
(c) Internal resorption of tooth
(d) Denticles
(c) Internal resorption is histologically manifested as
irregular lacunar resorption of internal surface of dentin,
showing osteoclasts or odontoclasts. Therefore, the term
odontoclastoma
- The source of calcified material in sclerotic dentin is now believed
to be
(a) Dental lymph located inside dentinal tubules
(b) Product of odontoblasts
(c) Exchange of ions from oral cavity
(d) Intratubular dentin
(a) The most likely source of calcium salts in sclerotic dentin is
now believed to be dental lymph fluid present around the
odontoblasts within the dentinal tubules.
- Transparent dentin is another name of
(a) Intratubular dentin
(b) Sclerotic dentin
(c) Dead tracts
(d) Physiologic secondary dentin
(b) Sclerotic dentin is so referred to because its refractive index
approaches that of air due to which it appears transparent
in ground sections
