Cleansable dentin

# Slow caries leading to formation of black, hard, cleansable dentin is called as:
 A. Reparative dentin
 B. Secondary dentin
 C. Eburnated dentin
 D. Arrested dentin

The correct answer is C. Eburnated Dentin.

An arrested dentinal lesion typically is 'open', dark and hard, and this dentin is termed as sclerotic or eburnated dentin.


Root caries of tooth

# Root caries is alarming because:
 A. It is near to apex
 B. It is symptomatic
 C. It is not seen
 D. It has rapid progression

The correct answer is D. It has rapid progression.

- Root surface caries may occur on the tooth root that has been exposed to the oral environment.
- Root caries is usually more rapid than other forms of caries, and thus should be detected and treated early.
- Root caries is becoming more prevalent because an increasing number of older persons are retaining more of their teeth and experiencing gingival recession, both of which increase the likelihood of root caries development.


Remineralization of Tooth

# The pH at which the remineralisation of damaged tooth structure occurs is said to be:
 A. 5.5
 B. 2.5
 C. 3.5
 D. 6.2

The correct answer is A. 5.5.

5.5 for 20 to 50 minutes is called as critical pH below which the tooth demineralizes and above remineralization occurs.

The critical pH for root surface demineralization is approximately 6 to 6.7


Absolute Contraindication for extraction of teeth

# An absolute contraindication for extraction of teeth is:
A. Hypertension
B. Myocardial infarction
C. Thyrotoxicosis
D. Central hemangioma 

The correct answer is D. Central hemangioma.

Hemorrhagic lesions: There are two entities that constitute absolute contraindications to exodontics: arteriovenous or sinusoidal aneurysms and central hemangiomas. (KRUGER)

Extraction of a tooth associated with a central hemangioma results in profuse bleeding and death of patients.

Relative contraindications:
- six months after a myocardial infarction
- extraction of teeth in previously irradiated areas
- presence or suspicion of hemangioma
- uncontrolled diabetes mellitus
- acute blood dyscrasias
- untreated coagulopathies
- necrotizing ulcerative gingivitis
- Adrenal insufficiency
- Thyrotoxicosis


Wound tissue and repair

# The word 'Patient' is derived from Latin word 'patiens' which means:
A. Disease
B. Suffering
C. Treatment
D. To cure

# "Sign of compression" is characteristically seen in:
A. Lipoma
B. Hernia
C. Vascular swelling
D. Sebaceous cyst

MCQs on Cardiopulmonary Resuscitation and Airway Maintenance

# The primary airway hazard for an unconscious patient in a supine position is:
A. Tongue obstruction
B. Bronchospasm
C. Laryngospasm
D. Aspiration

# Among the following, which is the rescue breathing in adult?
A. 6 times/min
B. 18 times/min
C. 12 times/min
D. 24 times/min

MCQs on Respiratory System Part 2

# Localised suppuration of lung is called:
A. an abscess
B. Empyema
C. Emphysema
D. Anasarca

# Not true about Pleurisy:
A. Pleural pain
B. Pleuropericardial rub
C. Usually secondary to lung infection
D. None of the above

Rapid Palatal Expansion

# Typically rapid palatal expansion is done with a jack screw that is activated at the rate of:
a) 1.0 to 2.0 mm/week
b) 1.0 to 2.0 mm/day
c) 0.5 to 1.0 mm/week
d) 0.5 to 1.0 mm/day   

The correct answer is D. 0.5 to 1.0 mm/day. 

Rapid expansion typically is done with two turns daily of the Jackscrew (0.5mm) activation. This creates 10 to 20 pounds of pressure across the mid palatal suture, which is enough to create microfractures of interdigitating bone spicules. In slow palatal expansion, approximately 0.5mm per week is the maximum rate at which the tissues of the midpalatal suture can adopt. 

Best space maintainer

# Best space maintainer is: 
a) Active space maintainer
b) Passive space maintainer 
c) Band and loop 
d) Pulpotomised primary tooth

The correct answer is D. Pulpotomised primary tooth.

Natural tooth if preserved by endodontic treatment is the best space maintainer because it provides easiness and more patient compliance and doesn't affect the eruption of the succedaneous tooth.


Respiratory System MCQs Part 1

# Pulmonary surfactant is:
A. Lecithin
B. Dipalmitoyl Phosphatidyl choline
C. Dipalmitoyl Phosphatidine serine
D. Sphingosine

# Heimilch Maneuver is carried out in:
A. Syncope
B. Airway obstruction
C. Carotid blow out
D. Cardiac arrest

Ideal Orthodontic Tooth Movement

# Resorption in case of ideal orthodontic tooth movement should be:
a) Undermining
b) Indirect
c) Frontal
d) Necrotic     

The correct answer is C. Frontal. 

Application of light orthodontic forces will result in frontal/ direct resorption. Frontal resorption occurs only when the forces applied are close to the capillary pressure, i.e. 20 -26 gm/ sq. cm of root surface area. 

Oppenheim and Schwarz have been given credit for discovering the optimum orthodontic force levels usually light continuous forces are recommended for tooth movement.

Scissor Bite

# Scissor bite is seen in:
a) Anterior cross-bite
b) Complete deep-bite
c) Total maxillary lingual cross-bite
d) Total maxillary buccal cross-bite   

The correct answer is D. Total maxillary buccal cross bite. 

When all the teeth are in scissors bite, the condition is called as Bodie syndrome.


Charcot Leyden Crystals

# Charcot Leyden crystals are breakdown products of:
A. Basophils
B. Eosinophil granules
C. Bile
D. Cholesterol granules or clefts

The correct answer is B. Eosinophil granules.

Charcot-Leyden crystals are seen in bronchial asthma. They are diamond shaped crystal seen in association with eosinophils. Repeated attacks may induce chronic bronchitis condition which in turn may develop into emphysema. 

Oxygen in histotoxic hypoxia

# The beneficial effect of oxygen therapy in histotoxic hypoxia is about:
A. 0 %
B. 50 %
C. 100 %
D. 30 %

The correct answer is A. 0%

Histotoxic hypoxia refers to hypoxia secondary to the inability of the cells to utilize oxygen.
In histotoxic hypoxia, oxygen therapy is  not beneficial as tissue oxygenation is itself defective. 

Transposition of Teeth

# The commonest teeth involved in transposition are:
a) Maxillary central incisor and lateral incisor
b) Maxillary canine and first premolar
c) Maxillary 1st premolar and 2nd premolar
d) Maxillary canine and Lateral incisor   

The correct answer is B. Maxillary canine and first premolar. 

Canine-first premolar transposition is the most common  transposition. 21. 

Canine-lateral incisor is the second most common transposition. 

Transposition is never seen in primary dentition. 

Average Leeway Space

# The average "Leeway space" available in each half of the maxilla is approximately:
a) 0.9 mm
b) 4.0 mm
c) 2.9 mm
d) 6.9 mm 

The correct answer is A. 0.9 mm.

The combined mesiodistal width of the permanent canines and premolars is usually less than that of deciduous canines and molars and this difference is known as Leeway Space of Nance. This space is used by the permanent lower molars during late mesial shift from end-on occlusion to class-I relation. The amount ot leeway space is about 1.8 mm (0.9 mm on each side of arch) in maxillary arch and about 3.4 mm in mandibular arch (1. 7 mm on each side of arch). 

Ugly duckling stage

# Ugly duckling stage affects:
a) Maxillary anterior teeth
b) Mandibular anterior teeth
c) Both Maxillary and mandibular teeth
d) Cause decrease in vertical height 

The correct answer is A. Maxillary anterior teeth. 

Ugly duckling stage is seen in maxillary central incisor region between 8 -9 years of age. This condition is seen during eruption of permanent canines. The developing canines displaces the roots of central and lateral incisors mesially and causes distal divergence of the crowns of the central incisors resulting in midline diastema. 

This type of malocclusion is not seen in lower arch because lower anteriors erupt almost simultaneously. Also, the path of eruption of mandibular canine is different from that of maxillary canines.


Canine placement

# Canine placed anterior to the orbital plane:
a) Protraction
b) Abstraction
c) Attraction
d) Expansion

The correct answer is A. Protraction.


ANB Angle Cephalogram

# An ANB angle 2 ° on the cephalogram usually indicates:
a) An unfavorable relationship of mandible to maxilla
b) A favorable relationship of maxillary alveolar base to mandibular alveolar base
c) Poor cranial growth with poor prognosis
d) Retruded maxillary incisor

The Correct answer is B. A favorable relationship of maxillary alveolar base to mandibular alveolar base.

SNA angle relates maxilla to the cranial base. The mean value is 82°. A Larger value indicates prognathic maxilla while a smaller value is suggestive of retrognathic maxilla.

SNB angle relates mandible to cranial base. Its average value is 80°. Larger values indicate prognathic mandible while smaller values indicates retrusive mandible.

AN B angle denotes the relative position of maxilla and mandible to each other. Mean value is 2° .

An increase in this angle indicates class-II skeletal tendency while an angle that is Less than normal or a negative angle is suggestive of a skeletal classIII relationship.

Frankfort's horizontal plane

# Frankfort's horizontal plane is formed by joining:
a) Porion and Orbitale
c) Porion and sella
b) Nasion and se lla
d) Porion and Nasion

The correct answer is A. Porion and Orbitale.

FHP or Frankfort horizontal plane =  Formed by joining Porion and orbitale
SN plane or anterior cranial base = Formed by joining nasion and sella
Cranial base length = Nasion and Bolton line
Upper facial height = Nasion to ANS (anterior nasal spine)
Lower facial height = ANS to menton
Total facial height = Nasion to menton


Prolonged retention of primary tooth

# Prolonged retention of primary tooth may lead to
a) Altered path of permanent tooth eruption
b) Root resorption of adjacent tooth
c) Ankylosis of permanent tooth
d) Warping of roots of adjacent teeth

The correct answer is A. Altered path of permanent tooth eruption.


Diagnosis in Orthodontics

# In a patient with competent lips together at rest, the lip line is opposite the tips of the upper incisors. The lip line is then described as:
a) Average
b) High
c) Incomplete
d) Low

# Following are "essential diagnostic criteria" according to Graber except:
a) Case history
b) Facial photographs
c) Periapical x-rays
d) Lateral cephalograms

# Incompetent lips refer to:
a) Inability of the Lips to cover the incisors in the mandibular relaxed position
b) Inability of the lips to cover the incisors in occlusion
c) The lips come in between the upper and lower incisors
d) Tongue thrusts against the lips during swallowing

# Mentalis muscle contraction causes the lower lip to:
a) Retrude
b) Protrude
c) Inversion
d) Eversion

# Transposition of teeth refers to:
a) Bucco rotation of 120°
b) Hypodontia
c) Teeth erupted in unusual position i.e, one tooth erupts in place of another
d) Inverted supernumerary teeth

# Carpel radiograph is used for assessment of:
a) Bone condition
b) Chronological age
c) Treatment plan
d) Skeletal maturation

# A reliable indicator of pubertal growth spurt on hand wrist films is sought as:
a) Ossification of adductor sessamoid
b) Appearance of hook of hamate
c) Ossification of all the carpal bones
d) Ossification of pisiform

# Dolicocephalic facial pattern is associated with:
a) Broad dental arch
b) Long and narrow dental arch
c) Paraboloid dental arch
d) Square dental arch

# Broad and short type of face is known as:
a) Mesoprosopic
b) Euryprosopic
c) Leptoprosopic
d) None of above

# Convex profile is seen in:
a) Class I
b) Class II
c) Class III
d) None of above

#  Facial divergence is:
a) Anterior placement of the midface
b) Inclination of the lower third of the face in relation to the forehead
c) Inclination of the upper third of the face to the middle third of the face
d) None of the above

# Fishman's index is used in relation with:
a) Population
b) Hand wrist radiographs
c) Cephalograms
d) Periodontal disease

# Brachy cephalic individual usually has:
a) Narrow dental arches
b) Broad dental arches
c) Normal dental arches
d) B or C

# The lip is supported by:
a) Relation of lip edge and facial surfaces of teeth
b) Labial sulcus between teeth and lip
c) Relationship of tongue and teeth
d) None

# Pletoric individual will have:
a) Tall and thin physique
b) Short and obese physique
c) Average physique
d) None of above

# Normal nasolabial angle:
a) 80°
c) 70°
b) 110°
d) 140°

# Hyperactive mentalis activity is seen in:
a) Class I
b) Class II division 1
c) Class II division 2
d) Class III

# Blanch test is used in diagnosis of:
a) Abnormal frenal attachments
b) Pseudo class III
c) Tongue thrusting
d) Tnumb sucking

# Backward path of mandibular closure is seen is:
a) Class II division 2
b) Class I
c) Pseudo class III
d) Class III

# Which of the following tests are employed to diagnose the mode of respiration?
a) Mirror test
c) Water test
b) Cotton test
d) All of the above

# The normal interincisal distance is:
a) 40 - 45 mm
b) 30 - 35 mm
c) 20 - 30 mm
d) 55 - 65 mm

# In gnathostatic models:
a) Maxillary cast is parallel to mandible cast
b) Maxillary cast is parallel to FH plane
c) Mandibular cast is parallel to FH plane
d) Both casts are parallel to FH plane

# Xeroradiography was invented by:
a) Chester F. Carlson in 1937
b) Simon
c) Hudson Kampula and Dickson in 1957
d) Hofrath and broad bent in 1934

# Ectomorphic, mesomorphic and endomorphic classification of body physique was given by:
a) Sheldon
b) Angle
c) LE Fouloun
d) Kielgren

# The Moyer's analyses requires the measurement of the:
a) Mesiodistal of the erupted permanent mandibular centrals and Laterals
b) Space available in the maxillary and mandibular posterior quadrants
c) Mesiodistal diameter of the unerupted premolars
d) Mesiodistal diameter of the unerupted maxillary and mandibular permanent cuspids and premolars

# Ashley-Howe model analysis is used to predict:
a) Tooth material excess
b) Maxillo-mandibular relationships
c) Basal bone-transverse relationship
d) Growth prediction

# Study models are used:
a) As references in orthodontic cases
b) To show shape, size and position of teeth
c) As an aid in treatment planning
d) All of the above

# Arch length analysis of a dentition shows a discrepancy of more than 10 mm. This indicates:
a) No extraction required if treated at an early age
b) No extraction required
c) Extraction of posterior teeth
d) Proximal stripping

# There are difference in completing a Hixon-Old father and Moyer's analysis. Of the following which would not be correct?
a) The Moyer's analysis requires the eruption of the mandibular permanent centrals and Laterals
b) The Hixon-Old father requires the eruption of the mandibular permanent centrals and laterals
c) The Hixon-Old father analysis requires the measured space available in all four posterior quadrants
d) The Moyer's analysis requires the measurement of the space available in the four posterior quadrants

# In which one of the following mixed dentition analysis of deciduous dentition there is no use of radiographs?
a) Carey's analysis
b) Moyer's analysis
c) Nance Carey's analysis
d) Pont's index

# The following is one of the mixed dentition analysis:
a) Tanaka Johnson
b) Counterpart analysis
c) Bjork analysis
d) Plaster cast analysis

# Which of the following analysis helps in determining the disproportion in the size between maxillary and mandibular teeth?
a) Pont's analysis
b) Bolton's analysis
c) Peck and Peck analysis
d) Carey's analysis

# Four dentists did study model analysis by Johnson and Tanaka; Moyer's, Stanley and Kerber, Wits analysis. Which one will give the best results:
a) Johnson and Tanaka
b) Moyer's
c) Stanley and Kerber
d) Wits

# Mixed dentition analysis was described by
a) Graber
b) Angle
c) Tweed
d) Moyer's

# In mixed dentition analysis, which tooth is used for classification:
a) Primary 1st molar
b) Primary 2nd molar
c) Permanent lst molar
d) B or C

#  Arch perimeter can be measured with:
a) Cephalogram
b) Brass wire
c) Vernier calipers
d) Occlusal radiograph

# Bolton analysis is used to determine
a) Arch length - tooth size discrepancy
b) Apical base length to arch perimeter
c) Tooth size ratio in the maxilla
d) Upper teeth to Lower teeth size ratio

#  In Pont's analysis
a) The width of 4 maxillary incisors is calculated
b) The width of 4 mandibular incisors is calculated
c) The width of 10 teeth anterior to first molars is calculated
d) The width of 12 teeth anterior to second permanent molars is calculated
e) The mesiodistal width and faciolingual width of mandibular centrals and laterals are taken individually

# The number of sites examined to assess the stages of bone maturation in Fishman's skeletal maturation index are:
a) 4
b) 5
c) 6
d) 7

#  SVED type of tooth plane is an example of:
a) Simple anchorage
b) Reciprocal anchorage
c) Extra oral anchorage
d) Reinforced anchorage

# In Peck and Peck index, mesiodistal and buccolingual measurements of which of the following tooth is taken:
a) Maxillary central incisor
b) Mandibular central incisor
c) Maxillary premolars
d) Mandibular molars

# Andrew's 5th key of occlusion is:
a) Curve of spee
b) Rotation absent
c) Tight contacts
d) Bolton's ratio

#  Lisping is associated commonly with which of the following malocclusions:
a) Anterior deepbite
b) Anterior crowding
c) Anterior open bite
d) Anterior retroclination

# The SCAN index is generally used as a :
a) Malocclusion index
b) Treatment need index
c) Treatment change index
d) Treatment of priority index

# According to American Board of Orthodontics recommendation for colour coding of sequential tracing, end treatment ceph tracing is done in:
a) Black
b) Blue
c) Red
d) Green

# Which of the following is not a type of mouth breathing?
a) Obstructing
b) Anatomical
c) Physiological
d) Habitual

# Tooth Loss that causes the patient to bite in an abnormal relation of maxilla to mandible, in order to obtain better function during mastication is termed:
a) Convenience bite
b) Dramatic bite
c) Temporary bite
d) Squashed bite

# The term applied when it is doubtful, according to mixed dentition analysis whether there will be space for all the teeth:
a) Space maintenance
b) Space regaining
c) Space supervision
d) None of the above

# For class II div 1 malocclusion of 14 years old boy, which analysis is indicated to detect the tooth extraction:
a) Bolton's analysis
b) Pont's analysis
c) Peck & peck analysis
d) Ashley & Howe's analysis

# A lingually erupting maxillary lateral incisor:
a) Is always indicative of arch length deficiency
b) Can be corrected by using a tongue blade if sufficient space exists in the arch
c) Is a self-correcting anomaly
d) Is to be extracted as early as possible to avoid a reflective pathway of the mandible

# The orthodontic diagnosis focuses on:
a) Full smile
b) Emotional smile
c) Social smile
d) Gummy smile only

# Fishman index is used for:
a) Skeletal growth maturation index
b) Dental growth maturation index
c) Arch length discrepancy
d) Prognathism of maxilla

# Which of the following is NOT a type of mixed dentition analysis?
a) Moyer's
b) Tanaka Johnston
c) Pont & Linderharth
d) Hixon old Father

# In a perfect smile, the ratio of width to height of maxillary incisor is?
a) 8:10
b) 6:8
c) 10:14
d) 20:25

# Study model with mounted base and trimmed height is:
a) 55 mm
b) 70 mm
c) 60 mm
d) 90 mm

# Three quarter profile photograph is used to detect:
a) Lip incompetence
b) Mandibular asymmetry
c) Midline
d) Midface deformity

# Which of the following is used to measure the mineral bone density of mandible?
a) Micro radiography
b) Auto radiography
c) Finite element modeling
d) Nuclear volume morphometry

Bacteria found in two days old plaque is:

# Predominant bacteria found in two days old plaque is:
A. Streptococci
B. Bacteroides
C. Spirochetes
D. Actinomyces

The correct answer is: A. Streptococci. 

- Plaque can be defined as a complex microbial community, with greater than 10^10 bacteria per milligram. 
- The formation of pellicle is the first step in plaque formation.
- "Primary colonizers" : The pellicle coated tooth surface is colonized by Gram- Positive aerobic cocci bacteria such as Streptococcus sanguis, Streptococcus mutans, and Actinomyces viscous. 
- Secondary colonizers: After 1 to 3 days, the secondary colonizers are gram negative anerobic rods and filaments that include Fusobacterium nucleatum, Prevotella intermedia, and Capnocytophaga species. 

Tertiary colonizers: After one week of plaque accumulation, other gram negative species may also be present in plaque. They include Porphyromonas gingivalis, Campylobacter rectus, Eikenella corrodens, Actinobacillus actinomycetemcomitans, and the oral spirochetes (Treponema species).

- The structural characteristics of dental plaque in this time period reveal complex patterns of bacterial cells of cocci, rods, fusiform, filaments, and spirochetes. 

- Particular specific associations of different bacterial forms have been observed . For example, the adherence of cocci to filaments results in a typical form referred to as "test tube brushes" or "corn cob" arrays. 

Storiform pattern of fibrous tissue

# Storiform pattern of fibrous tissue is seen in:
a. Fibrosarcoma
b. Malignant fibrous histiocytoma
c. Neurofibroma
d. Ameloblastic fibroma

The correct answer is: B. Malignant fibrous histiocytoma.

- are group of aggressive malignant neoplasms, arising from undifferentiated mesenchymal cells that differentiate along both fibroblastic and histiocyte pathways.
- Histologically the neoplasm reveals actively proliferating, numerous polyhedral or oval shaped, malignant histiocytes and many spindle shaped malignant fibrous cells.
- These malignant cells are often arranged in a typical "Cart-wheel" or "Storiform" pattern or Criss cross.
- Fibrous histiocytoma: Storiform pattern (helicopter in wheat field) is seen.


Oral Drive Theory

# The oral drive theory to explain thumb sucking habit was given by:
a) Benjamin
b) Sears and wise
c) Sigmund Freud
d) Scheldon

The correct answer is B. Sears and Wise.

According to ORAL DRIVE THEORY OF SEARS AND WISE, prolonged suckling lead to thumb sucking.

BENJAMIN'S TH EORY states that thumb sucking arises from the rooting or placing reflex. Rooting reflex is the movement of infant's head and tongue towards an object touching his cheek. The rooting reflex disappears in normal infants around 7-8 months of age.

According to SIGMOND FREUDIAN THEORY, in the oral phase of psychologic development, the mouth is believed to be an oro-erotic zone. The child has the tendency to place fingers or any other object into the oral cavity.

ORAL GRATIFICATION THEORY BY SHELDON states that if a child is not satisfied with sucking during the feeding period it will persist as a symptom of an emotional disturbance by digit sucking.

Gonial angle at birth

# The gonial angle at birth is?
a) 110°
b) 115°
c) 175°
d) 145°

The correct answer is D. 145 degrees.

 The mandibular or gonial angle during perinatal period ranges from 135° to 150°; however, soon after birth, it decreases to 130° to 140°. In adult mandible, the gonial angle measures between 110° to 120°. Studies have also indicated that the angle value of females is 3-5° greater than that of males.


Development of Maxilla

# Maxilla develops by:
a) Endochondral bone formation
b) Intra membranous bone formation
c) Cartilage replacement and intra membranous bone formation
d) Mostly cartilage replacement and a little by intra membranous

The correct answer is B. Intra membranous bone formation.

In endochondral type, the bone formation is preceded by formation of cartilaginous model, which is replaced by bone. Eg: Ethmoid bone, Hyoid, Incus, Stapes.

In intramembranous type, the formation of bone is not preceded by formation ot cartilaginous model. Instead bone is laid directly in a fibrous membrane. Eg: Maxilla, nasal bones, parietals, zygoma, vomer, lacrimal, zygomatic.

 Both intramembranous and endochondral ossification is seen in -occipital, temporal, sphenoid bones.


Father of Modern Orthodontics

# Father of modern orthodontics is:
a) Dewey
b) Angle
c) Andrew
d) Clark 

The correct answer is B. Angle. 

Pseudoepitheliomatous hyperplasia

# Which among the following shows pseudoepitheliomatous hyperplasia?
a) Squamous cell carcinoma
b) Basal cell carcinoma
c) Verrucous carcinoma
d) Granular cell myoblastoma

The correct answer is D. Granular cell myoblastoma.

Granular cell myoblastoma is a benign tumor of muscle tissue origin, most commonly involving tongue. The epithelium exhibits pseudoepitheliomatous hyperplasia because of which it is confused with epidermoid carcinoma.

Pseudoepitheliomatous hyperplasia is also seen in:
• Granular cell myoblastoma
• Blastomycosis
• Papillary hyperplasia
• DLE (Discoid lupus erythematosus)


High rate of Cancer

# Increased incidence of carcinoma is observed with:
a) Homogenous leukoplakia
b) Verrucous leukoplakia
c) Nodular leukoplakia
d) None of the above

The correct answer is C. Nodular Leukoplakia.

Clinically, Leukoplakia is of three types:
A. Homogenous
B. Speckled or Nodular
C. Proliferative verrucous leukoplakia (PVL)

A. Homogenous
• Appears as translucent white, raised area. • It is non-palpable i.e., same as surrounding mucous membrane.
• Differential diagnosis is hyperplastic lichen planus.

B. Speckled or Nodular 
• Raised from surface with red and white areas.
• Mostly seen at the angle of mouth and commissures of lips in chronic smokers.
• Indurations, fissuring and ulcer formation is seen
• The epithelial dysplasia is more common and has more tendency for malignancy.

C. Proliferative verrucous leukoplakia (PVL) 
• First described by Hansen and is associated with a high risk of progression to squamous cell carcinoma.
• May be associated with human papilloma virus (HPV)
• Seen as white papilliferous or cauliflower like growth
• Commonly seen in the region, where the quid is kept for long time
• No fixity is seen
• Differential diagnosis is verrucous carcinoma.

The forms of leukoplakia according to CURRENT classifications are:
1) Homogeneous: 
Lesions that are uniformly white.
a) Smooth
b) Furrowed (Fissured)
c) Ulcerated

2) Nonhomogeneous nodulospeckled: Lesion with well demarcated raised white areas, interspersed with reddened areas. It is applicable to both color (mixed red and white lesion -erythroleukoplakia) and texture (exophytic, papillary or verrucous).

Proliferative verrucous leukoplakia is a term used to describe a clinically aggressive form or oral leukoplakia with a strong potential for malignant transformation.


Elephantiasis neuromatosa

# Elephantiasis neuromatosa is a feature of:
a) Von Recklinghausen's disease
b) Neurilemmoma
c) Paraganglioma
d) Multiple endocrine neoplasia syndrome

The correct answer is A. Von Recklinghausen's disease.

Two distinct variants of Elephant man syndrome or von Recklinghausen's neurofibromatosis are known. Type 1 which is often associated with oral lesions and neurofibromatosis 2 (bilateral acoustic neurofibromatosis) is less common and is less frequently associated with obvious peripheral neurofibromatosis or oral lesions.


Flush Terminal Plane

# If a flush terminal plane is present in the deciduous dentition then the molars will erupt:
a) Initially in class I occlusion
b) Initially in class II occlusion
c) Initially in class III occlusion
d) End to end

The correct answer is D. End to End

Baume's classification of primary molars

Flush terminal plane : 
• The distal surface of upper and lower second deciduous molars are in one vertical plane.
• The permanent molars will erupt in a flush or end on relationship.

Mesial Step:
• The distal surface of lower second deciduous molar is more mesial to that of upper second deciduous molar.
• Mesial step- (normal mesial step of < 2mm, which is more common)- The permanent molars will erupt in Angle's class-I occlusion
• Exaggerated Mesial step of >2 mm- The permanent molars will erupt in Angle's classIII occlusion

Distal Step:
• The distal surface of lower second deciduous molar is distal to that of upper second deciduous molar.
• The permanent molars may erupt in Angle's class-II occlusion.


Cephalocaudal gradient of Growth

# Growth trends show that in most patients
a) maxilla and mandible grow in unison
b) maxilla grows more rapidly
c) mandible grows at a faster rate than the middle third of the face
d) no such conclusion could be made

The correct answer is: C. mandible grows at a faster rate than the middle third of the face.

The concept of "Cephalo-caudal gradient of growth" says that there is an axis of increased growth extending from the head towards the feet i.e., structures, which are far from brain grow more compared to other parts. When the facial growth pattern is viewed against the perspective of cephalocaudal gradient, it is not surprising that the mandible, being farther away from the brain tends to grow more and later than the maxilla, which is close to brain.


Primary displacement vs Secondary displacement

# The movement of bone in response to its own growth is termed as:
a) Rotation
b) Secondary displacement
c) Primary displacement
d) Differentiation

The correct answer is C. Primary displacement.

Types of Bone Growth:
Combinations of deposition and resorption occurring in different bones of skull resulting in growth movement towards depositary surface.

• It is the movement of whole bone as a unit.
• In primary displacement, the bone is displaced as a result of its own growth.
• In secondary displacement, the bone gets displaced as a result of growth and enlargement of adjacent bone.


Histopathological feature of basal cell carcinoma

# Characteristic histopathological feature of basal cell carcinoma is:
a) Nuclear palisading
b) Keratin pearls
c) Psammoma bodies
d) Foam cells

The correct answer is A. Nuclear palisading.

• In nodular basal cell carcinoma, the tumor cells typically have large, hyperchromatic, oval nuclei with little cytoplasm and nests of tumor cells show peripheral cell palisading.

• Keratin pearls are found in squamous cell carcinoma, while Psammoma bodies are concentric lamellated structures found in papillary thyroid carcinoma, meningioma, papillary serous cystadenocarcinoma of the ovary.

• Foam cells are found in verruciform xanthoma.


Granularity of oncocytes

# Granularity of oncocyte is due to:
a) Overabundance of golgi bodies
b) Overabundance of mitochondria
c) Deficiency of mitochondria
d) Deficiency of golgi bodies

The correct answer is B. Overabundance of mitochondria.

Oncocytoma is a rare benign salivary gland tumor composed of oncocytes with granular eosinophilic cytoplasm and a large number of atypical mitochondria. The name oncocytoma is derived from the resemblance of these tumor cells to apparently normal cells termed oncocytes found in salivary glands, respiratory tract, breast, thyroid, pancreas, parathyroid, pituitary, testicle, fallopian tube, liver and stomach. Electron microscopic studies have shown that cytoplasm of oncocyte is choked with mitochondria.


Sturge Weber Syndrome

# Sturge Weber syndrome is characterized by all EXCEPT:
a) Exophytic oral hemangioma
b) Facial hematoma
c) Tramline calcification of dura on lateral cephalogram
d) Facial hemangioma

The correct answer is B. Facial hematoma.

Though the skin and oral lesions of hemangioma are most deforming and disfiguring, the CNS involvement often results in serious problems of epilepsy, hemiplegia, mental retardation and retinal changes. Sturge-weber syndrome is probably the most common of these malformations. It is characterized by angiomatosis of face, laptomeningeal angiomas, contralateral hemiplegia, massive gingival growths and asymmetric jaw growth. The patients are treated for many years with phenytoin.


Most common site of Oral Leukoplakia

# Most common site of oral leukoplakia is :
a) angle of mouth
b) cheek mucosa
c) Soft palate
d) Gingiva

The correct answer is B. Cheek mucosa.


Standard airway for Ludwig's Angina

# Standard Airway for Ludwig's Angina is: a) Tracheotomy
b) Cricothyrotomy
c) Nasal intubation
d) Oral intubation

The correct answer is B. Cricothyrotomy.

In Ludwig's angina, cricothyrotomy is always preferred over option A, i.e., Tracheotomy. Tracheotomy is avoided because of the following reasons.
• Identification of landmarks is difficult due to associated massive edema and tissue distortion.
• Sometimes, tracheostomy may lead to spread of infection to deeper tissues.
• May result in Tracheal stenosis in 25 -50% of cases.
• Chances of getting pneumonia will always be there.

Trotter's Triad

# Trotter's triad is seen in:
a) Angiofibroma
b) Nasopharyngeal carcinoma
c) Laryngeal carcinoma
d) Growth in fossa of Rosenmuller

The correct answer is B. Nasopharyngeal carcinoma.

Trotter's triad:
1) Conductive deafness (Eustachian tube blockade)
2) lpsilateral temporoparietal neuralgia (Cranial Nerve V)
3) Palatal paralysis (Cranial Nerve X)


Nasopharyngeal carcinoma virus

#The virus associated with nasopharyngeal carcinoma is:
a) Epstein Barr
b) Cytomegalo virus
c) Hepatitis
d) Herpes virus

The correct answer is A. Epstein Barr.

Nasopharyngeal carcinoma affects younger age group and half of the patients will present with secondaries in neck.

Epstein-Barr virus is also implicated as an etiological factor for Burkitts Lymphoma and infectious mononucleosis.


Punched out edge of ulcer

# Punched out edge is characteristic of which type of ulcer?
a) Tuberculosis
b) Rodent
c) Syphilitic
d) Non specific

The correct answer is C. Syphilitic.

  •  Non-specific ulcer = Shelving edge
  • Tuberculous ulcer = Undermined edge
  • Rodent ulcer = Raised, pearly white and beaded 
  • Squamous cell carcinoma = Rolled out, everted 
  • Syphilitic = Punched out edge; Base covered with wash leather slough

Cellular response to Stress and Noxious Stimuli

Cellular responses to stress and noxious stimuli:
Normal cells handle normal physiologic demands, maintaining a steady state called homeostasis.

More severe physiologic stresses and some pathologic stimuli may bring about a number of physiologic and
morphologic cellular adaptations, during which new but altered steady states are achieved, preserving the viability of the cell.

The adaptive response may consist of an increase in the number of cells, called hyperplasia, increase in the
sizes of individual cells, called hypertrophy.

Conversely, Atrophy is an adaptive response in which there is a decrease in the size and function of cells.

Nature of the stimulus and Cell response/adaptation towards it
- Increased demand = Hyperplasia and hypertrophy
- Decreased nutrients and stimuli = Atrophy
- Chronic irritation = Metaplasia
- Reduced oxygen supply, chemical and microbial injury = Acute reversible injury
- Progressive damage including the DNA = Necrosis and Apoptosis
- Metabolic alterations = Intercellular accumulations and calcification

Mechanism of plasma membrane damage in ischemia

# The major mechanism of damage to plasma membrane in ischemia is:
A. Reduced intracellular pH
B. Increased intracellular accumulation of sodium
C. Increased Ca++ ions in the cytosol
D. Reduced aerobic respiration

The correct answer is C. Increased Ca++ ions in the cytosol.

The ion calcium is critical for cell damage. Influx of calcium acts as second messenger and activates wide spectrum of enzymes that destroy cellular organelles.


Most reactive free radical

# Out of the various free radical species, the following radical is most reactive:
A. Super oxide (O2
B. Hydrogen peroxide (H2O2
C. Hydroxyl (OH-
D. Nitric oxide (NO)

The correct answer is C. Hydroxyl ion.

Important mechanism of cell injury is by damage to DNA, proteins, lipid membranes, and circulating lipids (LDL) by peroxidation caused by oxygen derived free radicals--super oxide anion (O2-), hydroxy radical (OH-), and hydrogen peroxide (H2O2). Hydroxyl ion is most reactive.


Folic acid deficiency

# Folic acid deficiency is associated with administration of:
A. Phenytoin
B. Chloramphenicol
C. Isoniazide
D. Streptomycin

The correct answer is A. Phenytoin.

Folic acid deficiency can be caused by drugs that interfere with folate absorption or metabolism. Phenytoin, some other anticonvulsants, oral contraceptives, and isoniazide can cause Folic acid deficiency by interfering with Folic acid absorption. Other drugs such as methotrexate and, to a lesser extent, trimethoprim and pyrimethamine, inhibit dihydrofolate reductase and may result in a deficiency of folate cofactors and ultimately in megaloblastic anemia.


Fracture of the tooth bearing segment

# The fracture of the tooth bearing segment of the mandible is:
a) Simple
b) Complex
c) Compound
d) Comminuted

The correct answer is C. Compound.

• Simple fracture includes linear fracture of condyle, coronoid ramus and edentulous body or mandible.

• Compound fracture include fractures of tooth bearing portions of mandible.

• Green stick fracture is a rare type of simple fracture and is found exclusively in children.

• Comminuted fracture are due to direct violence to mandible from penetrating sharp objects and missiles.


Largest organ in the human body

# Largest organ in the body is:
A. Heart
B. Kidney
C. Skin
D. Liver

The correct answer is C. Skin.

Liver is the largest visceral organ in the body and is primarily in right hypochondrium and epigastric region,extending into left
hypochondrium ( or in right upper quadrant , extending into left upper quadrant)

Skin is the largest organ in human body.
Liver is the second largest organ of human body.
Liver is the largest gland in the human body.
The liver Is the largest of the abdominal viscera, occupying a substantial portion of the upper abdominal cavity.

It occupies most of the right hypochondrium and epigastrium, and frequently extends into the left hypochondrium as far as the left lateral line. As the body grows from infancy to adulthood the liver rapidly increases in size. This period of growth reaches a plateau around 18 years and is followed by a gradual decrease in the iver weight from middle age. The ratio of liver to body weight decreases with growth from infancy to adulthood.

The liver weighs approximately 5% of the body weight in infancy and it decreases to approximately 2% in adulthood. The size of the liver also varies according to sex, age and body size. The narrow end of the wedge lies towards the left hypochondrium, and the anterior edge points anteriorly and inferiorly.


Bisecting angle technique

# Bisecting angle technique is based on:
A. ALARA principle
B. SLOB Technique
C. Rule of Isometry
D. Convergence

The correct answer is C. Rule of Isometry.

The Bisecting angle technique is based on a simple geometric theorem, Cieszynski's rule of Isometry, which states that two triangles are equal when they share one complete side and have two equal angle.

Position of the film as close as possible to the lingual surface of the teeth, resting in the palate or on the floor of the mouth.

The plane of the film and the long axis of the teeth form an angle with its apex at the point where the film is in contact with the teeth.

Construct an imaginary line that bisects this angle and direct the central ray of the beam at right angles to this bisector.

This forms two triangles with two equal angles and  a common side. (the imaginary bisector)

Several methods can be used to support films intra orally for Bisecting angle projections.

The preferred method is to use a film holding instrument (e.g. The Snap-A-Ray) or Bisecting angle instrument. Both provide an external device for localizing the X ray beam.


Pathognomic sign of mandibular fracture

# The most common pathognomic sign of mandibular fracture is:
a) Malocclusion
b) Sublingual hematoma
c) Deviation of the jaw on opening
d) Paraesthesia of the mental nerve

The correct answer is B. Sublingual hematoma.

Sublingual ecchymosis is considered as pathognomonic sign of mandibular fracture.


Fracture of Mandible treatment

# The ideal treatment for fracture of the angle of mandible is:
a) Transosseous wiring
b) Intermaxillary fixation
c) Plating on the lateral side of the body of the mandible
d) Plating at the inferior border of the mandible

The correct answer is D. Plating at the inferior border of the mandible.

Compression plates are used at inferior border of mandible below the inferior dental canal. If there is opening of the upper border, it is necessary to apply a tension band in the form of arch bar or miniplates at the upper border.


Gowgates technique Landmarks

# Extra-oral landmark for Gowgates technique of mandibular nerve block:
a) Corner of the mouth
b) Intertragic notch
c) Both of the above
d) None of the above

The correct answer is C. Both of the above

Landmarks for Gow-Gates technique:
a. Extraoral:
• Lower border of tragus (intertragic notch); • Corner of mouth
• Mesiolingual cusp of maxillary 2nd molar

 b. Intraoral:
• Height of injection established by placement of the needle tip just below the mesiolingual (mesiopalatal) cusp of maxillary second molar.
• Penetration of soft tissues just distal to the maxillary second molar at the highest established in the preceding step.


Long duration of anesthesia

# Long duration anesthesia is achieved by:
a) 2% Lidocaine HCL +Epinephrine 1:200000
b) 3% Mepivacaine HCL
c) 4% Prilocaine HCL +Epinephrine 1:200000
d) 0.5% Bupivacaine+ Epinephrine 1:200000

The correct answer is D. 0.5% Bupivacaine+ Epinephrine 1:200000

Short Duration (pulpal anesthesia approximately 30 Minutes)
• Mepivacaine HCl 3%
- Prilocaine HCl 4% (by infiltration)

Intermediate Duration (Pulpal anesthesia approximately 60 Minutes) 
• Articaine HCL 4% + epinephrine 1:100,000 • Articaine HCl 4% +epinephrine 1:200,000
• Lidocaine HCl 2% +epinephrine 1:50,000
• Lidocaine HCl 2% +epinephrine 1:100,000
• Mepivacaine HCl 2% + levonordefrin 1:20,000
• Prilocaine HCl 4% (via nerve block only)
• Prilocaine HCl 4% +epinephrine 1:200,000

 Long Duration (Pulpal anesthesia approximately 90+ Minutes) 
• Bupivacaine HCl 0.5% + epinephrine 1:200,000 (by nerve block)


Muscle pierced while giving IANB

#Which of the following muscles is pierced by the needle while giving an inferior alveolar nerve block?
a) Medial pterygoid
b) Temporalis
c) Superior constrictor
d) Buccinator

The correct answer is D. Buccinator.


Non rigid Connectors, Fixed Partial Dentures

# The non-rigid connectors are used in the construction of FPD when the span is:
a) Short, supplementing alveolar ridge reduction
b) Short supplementing alveolar ridge reduction not required
c) Long, supplementing alveolar ridge reduction
d) Long, supplementing alveolar ridge reduction not required

  • The correct answer is B. Short supplementing alveolar ridge reduction not required

Gingival finish line on tipped molar

# The gingival finish line on a tipped molar should be:
a) Shoulder
b) Chamfer
c) Knife edge
d) Feather edge

The correct answer is C. Knife edge.

When molars are tipped or rotated, a reverse 3/4th crown is indicated.


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