Nerve of pterygoid canal is also known as:

 # Nerve of pterygoid canal is also known as:

A. Vidian nerve

B. Radial nerve

C. Musician’s nerve

D. None of the above

The correct answer is a. Vidian nerve.

The vidian nerve (also known as the nerve of the pterygoid canal) is formed by the union of the deep and greater petrosal nerves, the latter being a branch of the facial nerve at the level of the geniculate ganglion.

The nerve of the pterygoid canal (Vidian nerve) is formed by the junction of the greater petrosal nerve and deep petrosal nerve, which passes from the foramen lacerum to the pterygopalatine fossa through the pterygoid canal.

Proximal segment of mandibular angle fracture

 # The proximal segment of mandibular angle fracture usually displaced in which direction ?

a. Anterior and superior

b. Posterior and inferior

c. Inferior only

d. Posterior and superior

The correct answer is A. Anterior and superior.

Fractures of angle of mandible are influenced by the pull of medial pterygoid, masseter and temporalis

muscles, which displace the ramus in superior and anterior direction. This is a liorizontally unfavorable

fracture.

Golden period for treatment of open wound is?

# Golden period for treatment of open wound is? 

A. 2 hrs 

B. 4 hrs

C. 6 hrs 

D. 8 hrs 

The correct answer is B. 4 hours.

In the first 4 hours after a breach in an epithelial surface and underlying connective tissues, there is delay in the mobilisation of host defences. This period is called 'decisive period' and during this period bacterial colonisation and established infection can begin. It is logical that prophylactic antibiotics will be most effective during this time.

Tessier classification is used for

 

 # Tessier classification used for 

A. Isolated cleft palate 

B. Facial cleft 

C. TMJ internal disorder 

D. White lesion of oral mucosa 

The correct answer is B. Facial cleft.

Dr. paul Tessier, the father of the field of craniofacial surgery, developed a classification system for craniofacial clefts that is the most widely used of those available today.

Rhytidectomy is associated with which nerve involvement?

 # Rhytidectomy is associated with which nerve involvement? 

A. Great auricular nerve 

B. Auriculotemporal nerve 

C. Marginal mandibular nerve 

D. Sympathetic plexus around ICA 

The correct answer is A. Greater auricular nerve.

Rhytidectomy is a surgical procedure meant to counteract the effects of time on the aging face. In the rhytidectomy procedure (also known as a “face-lift”), the tissues under the skin are tightened and excess facial and neck skin are excised. Rhytidectomy literally means wrinkle (rhytid-) removal (-ectomy).

The great auricular nerve, which supplies sensation to the skin of the ear and nearby skin is the most commonly injured in a rhytidectomy.

The probability of rejecting the null hypothesis when it is true:

 # The probability of rejecting the null hypothesis when it is true:

A. Type 1 error

B. Type 2 error

C. Power of a statistical test

D. Level of significance

The correct answer is A. Type I error.

In statistical hypothesis testing, a type I error is the mistaken rejection of an actually true null hypothesis (also known as a "false positive" finding or conclusion; example: "an innocent person is convicted"), while a type II error is the failure to reject a null hypothesis that is actually false (also known as a "false negative" finding or conclusion; example: "a guilty person is not convicted"). Much of statistical theory revolves around the minimization of one or both of these errors, though the complete elimination of either is a statistical impossibility if the outcome is not determined by a known, observable causal process. By selecting a low threshold (cut-off) value and modifying the alpha (α) level, the quality of the hypothesis test can be increased. The knowledge of type I errors and type II errors is widely used in medical science, biometrics and computer science.

The immunoglobulin which is produced first by the fetus in response to infection is:

#  The immunoglobulin which is produced first by the fetus in response to infection is:

A. IgG

B. IgA

C. IgM

D. IgD

The correct answer is C. IgM.

Phylogenetically, IgM is the oldest immunoglobulin class. It is also the earliest immunoglobulin to be synthesized by the fetus beginning by about 20 weeks of age. As it is not transported across the placenta, the presence of IgM in the fetus or newborn indicates intrauterine infection and its detection is useful in the diagnosis of congenital infections such as syphilis, rubella, HIV infection and toxoplasmosis. 

Normal submandibular salivary gland in sialograph shows

 # Normal submandibular salivary gland in sialograph shows

a. Tree in winter appearance

b. Bush in winter appearance

c. Herb in winter appearance

d. Shrub in winter appearance

The correct answer is B. Bush in Winter Appearance.

Normal sialographic appearances of the submandibular gland

These include:

• The main duct is of even diameter (3-4 mm wide) and should be filled completely and uniformly.

• This gland is smaller than the parotid, but the overall appearance is similar with the branching duct structure tapering gradually towards the periphery — the so-called bush in winter appearance.

Minor salivary gland found along the lateral border of tongue is:

#  Minor salivary gland found along the lateral border of tongue is:

A. Gland of Von Ebner

B. Gland of Weber

C. Gland of Blandin and Nuhn

D. Foliate glands

The correct answer is B. Gland of Weber.

Gland of von Ebner are posterior lingual glands, glands of Blandin and Nuhn are anterior lingual glands while Foliate is papilla present in lateral border of tongue. 

The Weber's glands are muciparous glands on the side of the tongue. They are a minor salivary gland in the peritonsillar space. The glands are named after German anatomist Moritz Ignaz Weber. They clear the peritonsillar space of debris.

Coleman sign is seen in :

 # Coleman sign is seen in :

a. Hard palate 

b. Soft palate 

c. Floor of mouth 

d. None 

The correct answer is C. Floor of Mouth.

During mandibular anterior region fracture submuosal haematoma is seen the lingual surface of mandible at the floor of mouth known as coleman sign.

Break up time test is done for:

# Break up time test is done for:

a. Sjogren’s syndrome

b. Scleroderma

c. Myasthenia gravis

d. Guillian barre syndrome

The correct answer is a. Sjogren's syndrome.

Tear break-up time (TBUT) also known as tear film break-up time (TFBUT) is the time taken for the first dry spot to appear on the cornea after a complete blink. TFBUT measurement is an easy and fast method used to assess the stability of tear film. It is a standard diagnostic procedure in the dry eye clinics. 

Tear film break-up time is abnormal in several conditions like aqueous tear deficiency, keratoconjunctivitis sicca, mucin deficiency, and meibomian gland disorders. Evaporative dryness can also be seen in conditions like lagophthalmos, proptosis, Parkinson's disease, computer vision syndrome, contact lens use, drugs (antihistamines, beta blockers, antispasmodics, diuretics) and vitamin A deficiency, amongst others. 

First order bends are:

 # First order bends are: 

a) Tipping bends. 

b) Torquing bends. 

c) In and out bends. 

d) Anchorage bends. 

The correct answer is C. In and out bends.

First Order Bends

The first order bends or in-out bends are placed to compensate for differences in the buccolingual prominence of the teeth. They comprise of the lateral inset, the canine offset and the molar offset.

Second Order Bends

The second order bends are placed to achieve correct mesiodistal axial inclination of teeth. They comprise the tip back bends placed in the posterior segments.

Third Order Bends

The third order bends or torque are placed to get correct buccolingual position by moving the roots. They are placed by twisting the arch wire. 

What tends to maintain the integrity of a bone implant interface?

 

# _______ tend to maintain the integrity of a bone implant interface:

a. Compressive force 

b. tensile force 

c. Shear force 

d. All the above 

The correct answer is A. Compressive force.

Forces may be described as compressive, tensile, or shear. Compressive forces attempt to push masses toward each other. Tensile forces pull objects apart. Shear forces on implants cause sliding. Whereas compressive forces tend to maintain the integrity of a bone–implant interface, tensile and shear forces tend to distract or disrupt such an interface. Shear forces are most destructive to implants and bone compared with other load modalities. In general, compressive forces are accommodated best by the complete implant–prosthesis system. Cortical bone is strongest in compression and weakest in shear.

Atherosclerosis is due to:

 # Atherosclerosis is due to 

a. HDL receptor defect 

b. apolipoprotein E deficiency 

c. decreased LDL activity 

d. decreased lipoprotein lipase 

The correct answer is B. Apolipoprotein E deficiency.

Apolipoprotein (apo) E is recognized for its unparalleled ability to suppress atherosclerosis .The expression of apoE in the macrophage has long been recognized to suppress atherosclerosis by preventing foam cell formation in the vessel wall.

APOE was initially recognized for its importance in lipoprotein metabolism and cardiovascular disease. Defects in APOE result in familial dysbetalipoproteinemia aka type III hyperlipoproteinemia (HLP III), in which increased plasma cholesterol and triglycerides are the consequence of impaired clearance of chylomicron, VLDL and LDL.

An amalgam restoration is considered:

 # An amalgam restoration is considered _____.

A. Primary prevention

B. Secondary prevention

C. Tertiary prevention

D. Both primary and tertiary prevention

The correct answer is B. Secondary prevention.

Secondary prevention is the elimination or reduction of a disease after it occurs. An amalgam restoration is considered secondary prevention because tooth decay is removed and a restoration is placed. 

Amount of fluoride in smear size toothpaste for children age less than 3 years:

 # Amount of fluoride in smear size toothpaste for children age less than 3 years: 

a. 0.1mg 

b. 0.2 mg 

c. 0.5 mg 

d. 1 mg 

The correct answer is A. 0.1 mg.

For children younger than 3 years, caregivers should begin brushing children's teeth as soon as they begin to come into the mouth by using fluoride toothpaste in an amount no more than a smear or the size of a grain of rice. Teeth should be brushed thoroughly twice per day (morning and night) or as directed by a dentist or physician. Children's brushing should be supervised to ensure that they use the appropriate amount of toothpaste.

Source: AAPD recommendation 2021

A person with glaucoma should not receive:

 # A person with glaucoma should not receive: 

a. Sedatives 

b. Vasoconstrictors 

c. Anti-sialogogues 

d. Local anesthetics 

The correct answer is C. Anti-sialogogues.

Antimuscarinic mydriatics like tropicamide, cyclopentolate, etc. produce both mydriasis and cycloplegia, and tend to raise i.o.p. in glaucoma patients. Therefore, antimuscarinics are to be avoided in glaucoma patients. 

Procedure necessary to preserve and restore anterior guidance

 # A dentist is preparing all maxillary anterior teeth for metal-ceramic crowns. Which of the following procedures is necessary to preserve and restore anterior guidance? 

A. Protrusive record 

B. Template for provisional restorations 

C. Custom incisal guide table 

D. Interocclusal record in centric relation 

The correct answer is C. Custom incisal guide table.

Anterior guidance must be preserved by means of construction of a custom incisal guide table, especially when restorative procedures change the surfaces of anterior teeth that guide the mandible in excursive (lateral, protrusive) movements. 

A cyst formed when the stellate reticulum degenerates:

 # A cyst formed when the stellate reticulum degenerates: 

a. Eruption cyst 

b. Dentigerous cyst 

c. Keratocyst 

d. Radicular cyst 

The correct answer is A. Eruption cyst.

An eruption cyst is a type of dentigerous cyst formed when the stellate reticulum degenerates, leaving a cavity lined by the outer enamel epithelium before or during tooth eruption.

Eruption cyst is defined as an odontogenic cyst with the histologic features of a dentigerous cyst that surrounds a tooth crown that has erupted through bone but not soft tissue and is clinically visible as a soft fluctuant mass on the alveolar ridges.

An eruption cyst or ‘eruption hematoma’ is in fact a dentigerous cyst occurring in the soft tissues (Shear, 1992). Whereas the dentigerous cyst develops around the crown of an unerupted tooth lying in the bone, the eruption cyst occurs when a tooth is impeded in its eruption within the soft tissue overlying the bone.

60-74 micrometer sized particles contained in:

 # 60-74 micrometer sized particles contained in: 

A. Coarse grit diamond bur 

B. Medium grit diamond bur 

C. Fine grit diamond bur 

D. Very fine grit diamond bur 

The correct answer is C. Fine grit diamond bur.

The particle sizes of coarse, medium, fine and very fine grit diamond burs are 125-150 micrometer, 88-125 micrometer, 60-74 micrometer and 38-44 micrometer respectively. 

The width of keratinized gingiva is measured as the distance from the:

 # The width of keratinized gingiva is measured as the distance from the: 

A. Free gingival margin to the mucogingival junction 

B. Cementoenamel junction to the mucogingival junction 

C. Free gingival groove to the mucogingival junction 

D. Free gingival margin to the base of the pocket 

The correct answer is A. Free gingival margin to the mucogingival junction.

Keratinized gingiva extends from the free gingival margin to the mucogingival junction. The attached gingiva extendsfrom the free gingival groove to the mucogingival junction. 

What is a second-order bend in orthodontic wire?

# What is a second-order bend in orthodontic wire? 

A. Bend to position a tooth buccolingually 

B. Bend to provide angulation of a tooth in mesiodistal direction (tip) 

C. Bend to provide correct angulation of a tooth in labiolingual direction (torque) 

D. Bend to rotate a tooth 

The correct answer is B. Bend to provide angulation of a tooth in mesiodistal direction (tip) 

A second-order bend is placed to provide angula tion of a tooth in the mesiodistal direction, also called “tip.” A first-order bend is placed in an arch wire to position a tooth in the labiolingual direc tion (in-out bend) or to rotate a tooth as seen in the occlusal plane. A bend to provide angulation in the labiolingual direction is called a third-order bend (torquing bend). 

The membrane that separates the enamel organ and the dental papilla just prior to dentin formation is called:

 # The membrane that separates the enamel organ and the dental papilla just prior to dentin formation is called:

A. Inner enamel epithelium

B. Outer enamel epithelium

C. Membrana preformativa

D. Cell-free zone

The correct answer is C. Membrana preformativa.

The dental papilla is enclosed in the invaginated portion of the enamel organ. Before the inner enamel epithelium begins to produce enamel, the peripheral cells of the mesenchymal dental papilla differentiate into odontoblasts under the organizing influence of the epithelium. First, they assume a cuboidal form; later they assume a columnar form and acquire the specific potential to produce dentin. The dental papilla ultimately gives rise to dental pulp, once the dentin formation begins at the cuspal tip of the bell stage tooth germ. The basement membrane that separates the enamel organ and the dental papilla just prior to dentin formation is called the membrana preformativa.

Which of the following is true of cellular cementum?

 # Which of the following is true of cellular cementum?

A. Forms during root formation

B. Forms after eruption of the tooth

C. Seen at the coronal portion of the tooth

D. Formation is a slow process

The correct answer is B. Forms after eruption of the tooth. 

The cellular cementum is also known as secondary cementum as this is formed later than the AEFC (Acellular Extrinsic Fiber Cementum). The cellular cementum found in the apical third is mainly of two types—the cellular mixed fiber cementum which forms the bulk of secondary cementum and occupies the apical interradicular regions and the CIFC (Cellular intrinsic fiber cementum) which is present in the middle and apical third. These types are mainly involved in the adaptation and repair of cementum. Since the secondary cementum is formed rapidly the incremental lines are placed further apart than in AEFC (Acellular Extrinsic Fiber Cementum).

Reference: Orban's Oral Histology and  Embryology

Which of the following is indicative of ageing?

 # Which of the following is indicative of ageing?

A. Expression of dead tracts

B. Widening of predentin

C. Increase in tubular diameter

D. Increase in peritubular dentin

The correct answer is A. Expression of dead tracts. 

It is rather difficult to separate age and functional changes in dentin. Dentin is laid down throughout life. This dentin is termed secondary dentin. If dentin forms as a result of pathological process, like caries, it is termed tertiary dentin. Tertiary dentin shows irregularity in size, shape, number and arrangement of dentinal tubules. Dentinal tubules degenerate due to injury resulting in the formation of dead tracts. Mineralization of dentinal tubules results in the formation of sclerotic dentin. This makes the tooth to appear transparent in these areas.

Reference: Orban's Oral Histology and Embryology

The formation of hard tissue takes place in the:

 # The formation of hard tissue takes place in the:

A. Bud stage

B. Cap stage

C. Advanced bell stage

D. Early bell stage

The correct answer is C. Advanced bell stage.

Advanced bell stage is characterized by the commencement of mineralization and root formation. During the advanced bell stage, the boundary between inner enamel epithelium and odontoblasts outlines the future dentinoenamel junction. The formation of dentin occurs first as a layer along the future dentinoenamel junction in the region of future cusps and proceeds pulpally and apically.

Reference: Orban's Oral Histology and Embryology, 14th Edition

Paget’s test is done in the examination of

 # Paget’s test is done in the examination of:

A. A small swelling

B. Serum calcium

C. Urine analysis for alkaline phosphatase

D. Cytologic smear

The correct answer is A. A small swelling.

Paget's test is done for small swellings to know the consistency (cystic/solid). The centre and peripheries are palpated with index finger. Cystic swelling feels softer at centre than periphery whereas solid swelling feels firmer at center than periphery.

Which of the following is a general property of biofilms?

 # Which of the following is a general property of biofilms? 

a. Susceptible to host defenses. 

b. Limited habitat range. 

c. Open architecture.

d. Reduced virulence

The correct answer is C. Open architecture.

The close relationships between the architecture of a biofilm and its functional properties emphasizes the need to better describe and understand cell behavior, from single cell to multicellular scale, during biofilm structure development and maturation. Recent technological advances in methodologies including imaging and microscopy, molecular techniques, and physico-chemical assays, enabled the development of novel approaches dedicated to biofilm studies (Azeredo et al., 2017). The possibility to observe biofilm using high resolution and non-destructive methods now allows investigating the dynamics of multicellular structure development and the fate of each of its individual cellular components in parallel. For instance, the key architectural transitions and associated biophysical and genetic mechanisms supporting the developmental program of Vibrio cholerae biofilms have been recently disclosed using single-cell live imaging (Drescher et al., 2016; Yan et al., 2016). This kind of observations has clearly improved our understanding of spatio-temporal development of biofilms and has finally increasingly supported the intimate connection between structural modulations and the emergence of functional features and survival strategies. Indeed, the ability of biofilms to adapt their structure in response to internal or external stimuli, called hereafter the architectural plasticity, appears as a key factor affecting the fitness of individuals within the whole microbial community. Interestingly, the role of plasticity in bacterial survival was already demonstrated at the cellular scale. Bacteria are able to alter their morphology and to produce specific morphotypes conferring survival advantages in hostile environments. This was showed for numbers of bacterial pathogens for which filamentation is essential in the resistance to phagocytosis and overall for persistence during infection. 

Reference: https://www.frontiersin.org/articles/10.3389/fmicb.2017.01364/full

Boiling point of methyl methacrylate is:

# Boiling point of methyl methacrylate is:

A. Greater than B.P of water 

B. Lesser than B.P of water 

C. Equal to BP of water 

D. Is at normal room temperature 

The correct answer is A. Greater than Boiling Point of Water. 

Methyl methacrylate (MMA) is an organic compound with the formula CH2=C(CH3)COOCH3. This colorless liquid, the methyl ester of methacrylic acid (MAA), is a monomer produced on a large scale for the production of poly(methyl methacrylate) (PMMA).

Melting point : −48 °C (−54 °F; 225 K)

Boiling point : 101 °C (214 °F; 374 K)

Flow of Oxygen in Oxygen flush system

 # The oxygen flush system provides a higher flow of oxygen of ________ L/min when the patient’s need for oxygen is greater than the amount the breathing circuit can provide. 

a) 25-50 

b) 35-75 

c) 55-95 

d) 65-105 

The correct answer is B. 35-75.

Many anesthesia providers use the oxygen flush valve daily especially in those cases where the face mask fit is not optimal during the induction. When an emergency occurs it is comforting to know where a supply of oxygen is readily located, how much can be delivered, and that a flow is available despite the anesthesia being lifted on or off.

The oxygen flush can be used even when the anesthesia machine is not turned on and will operate in its regular fashion. It delivers oxygen straight from the pipeline or cylinder regulator at 45-50 psig (Pounds per square in gauge). The flow rate will be between 35-75 L/min. 

Acetone breath is a feature of:

 # Acetone breath is a feature of:

A. Sinusitis

B. Renal disease

C. Liver disease

D. Diabetes mellitus

The correct answer is D. Diabetes mellitus.

Diabetic ketoacidosis (DKA) is a potentially life-threatening complication of diabetes mellitus. Signs and symptoms may include vomiting, abdominal pain, deep gasping breathing, increased urination, weakness, confusion and occasionally loss of consciousness. A person's breath may develop a specific "fruity" smell. Onset of symptoms is usually rapid. People without a previous diagnosis of diabetes may develop DKA as the first obvious symptom.

DKA happens most often in those with type 1 diabetes but can also occur in those with other types of diabetes under certain circumstances. Triggers may include infection, not taking insulin correctly, stroke and certain medications such as steroids. DKA results from a shortage of insulin; in response, the body switches to burning fatty acids, which produces acidic ketone bodies. DKA is typically diagnosed when testing finds high blood sugar, low blood pH and ketoacids in either the blood or urine.

On physical examination there is usually clinical evidence of dehydration, such as a dry mouth and decreased skin turgor. If the dehydration is profound enough to cause a decrease in the circulating blood volume, a rapid heart rate and low blood pressure may be observed. Often, a "ketotic" odor is present, which is often described as "fruity" or like "pear drops". The smell is due to the presence of acetone. If Kussmaul respiration is present, this is reflected in an increased respiratory rate.

Small children with DKA are relatively prone to brain swelling, also called cerebral edema, which may cause headache, coma, loss of the pupillary light reflex, and can progress to death. It occurs in about 1 out of 100 children with DKA and more rarely occurs in adults.

Glass ionomer cement was introduced by Wilson and Kent in:

 # Glass ionomer cement was introduced by Wilson and Kent in:

a.1969

b.1972

c.1896

d.1989

The correct answer is B. 1972.

Glass ionomer cements are adhesive tooth colored anticariogenic restorative materials which were originally used for restorations of eroded areas. Current glass ionomers have been modified to allow a wider application. These cements evolved from a general dissatisfaction with silicate cements. The first usable glass ionomer system was formulated in 1972 by Wilson and Kent and was known as ASPA (alumino silicate polyacrylic acid). Subsequently great improvements were made and today these materials are very popular and widely used.

Crepitus will be seen in the tissues surrounding an infection by:

 # Crepitus will be seen in the tissues surrounding an infection by:

A. Staphylococcus

B. Streptococcus

C. Clostridium tetani

D. Clostridium perfringes

The correct answer is D. Clostridium perfringes. 

■ Clostridium perfringens causes gas gangrene or myonecrosis. 

■ Gas gangrene is characterized by skin colour change from pallor to bronze/purple discoloration and the skin is tense and exquisitely tender. 

■ Gas in the tissues may be obvious with crepitus on clinical examination or visible on radiograph. 

■ Surgical debridement, antibiotic therapy with high-dose I.V penicillin, clindamycin and metronidazole and hyperbaric oxygen therapy are used for treating gas gangrene [Note: Hyperbaric oxygen therapy is also used for osteoradionecrosis and chronic osteomyelitis]. 

■ Cl. tetani causes tetanus and cl. difficile causes pseudomembranous colitis. 

Acute rheumatic fever occurs most commonly in:

 # Acute rheumatic fever occurs most commonly in:

A. 5-14 years

B. 15-20 years

C. 21-25 years

D. 26-30 years

The correct answer is A. 5-14 years.

The incidence of acute rheumatic fever is highest in school aged children. The highest incidences recorded are in those aged 5-14 years. One study reported a median age of diagnosis of acute rheumatic fever of 10.4 years with an interquartile range between 8.7-14.3 years. 

The active ingredient of anticalculus dentifrices is:

 # The active ingredient of anticalculus dentifrices is:

A. Fluoride

B. Potassium nitrate

C. Ammonia

D. Pyrophosphate

The correct answer is D. Pyrophosphate.

Pyrophosphate has received particular attention in view of its proposed rote in inhibition of crystal growth. Nevertheless, it is unlikely that pyrophosphate in toothpastes will persist for a reasonable length of time in the mouth, because of the presence of considerable amounts of pyrophosphatase enzymes in saliva and oral bacteria. Pyrophosphate, when introduced into a simulated oral environment, is hydrolyzed by various phosphatases with concomitant loss of its inhibitory activity for calcification in vitro. To overcome this problem, a copolymer of vinyl methyl ether maleic anhydride (Gantrez) and NaF has been introduced in order to inhibit the hydrolysis of pyrophosphate. Animal and clinical studies have shown that toothpaste containing a combination of pyrophosphate, NaF and Gantrez, was highly effective in retarding supragingival calculus formation. 

Disease transmitted from father to all daughters would be:

 # Disease transmitted from father to all daughters would be:

A. Autosomal dominant

B. Autosomal recessive

C. X linked dominant

D. Mitochondrial

The correct answer is C. X linked dominant.

Father gives X to daughter and Y to son. Any X linked dominant disorder in father will affect all daughters. 

Compound odontoma shows on a radiograph as:

 # Compound odontoma shows on a radiograph as:

A. Supernumerary teeth

B. Radiolucent and radiopaque areas

C. Mass of calcified areas

D. Distinguishable tooth like structures

The correct answer is D. Distinguishable tooth like structures.

The radiographic appearance of the odontoma is characteristic. Since most odontomas are clinically asymptomatic and are discovered by routine radiographic examination, the dentist should be familiar with their appearance. They are often situated between the roots of teeth and appear either as an irregular mass of calcified material surrounded by a narrow radiolucent band with a smooth outer periphery, or as a variable number of tooth like structures with the same peripheral outline. This latter type of odontoma may contain only a few structures resembling teeth, or it may contain several dozen. Both forms of odontoma are frequently associated with unerupted teeth. It is of interest that the majority of odontomas in the anterior segments of the jaws are compound composite in type, while the majority in the posterior areas are complex composite.

APC gene is mutated in:

 # APC gene is mutated in:

A. Hereditary intestinal polyposis syndrome

B. Gardner’s syndrome

C. Gorham stout syndrome

D. Caffey Silverman Syndrome

The correct answer is B. Gardner's syndrome.

Gardner syndrome, inherited as an autosomal-dominant disorder, is characterized by intestinal polyposis, multiple osteomas, fibromas of the skin, epidermal and trichilemmal cysts, impacted permanent and supernumerary teeth, and odontomas. The genetic defect is found in a small region on the long arm of chromosome 5 (5q21), where the familial adenomatous polyposis (APC) gene resides. Most patients with Gardner’s syndrome do not exhibit the complete spectrum of clinical disease expression. Osteomas associated with this syndrome may be found in the jaws (especially the mandibular angle) and in facial and long bones. Intestinal polyps associated with Gardner syndrome are commonly located in the colon and rectum. Significantly, these polyps, found microscopically to be adenomas, exhibit a very high rate of malignant transformation to invasive colorectal carcinoma.

Reference: ORAL PATHOLOGY: CLINICAL PATHOLOGIC CORRELATIONS, SEVENTH EDITION, Joseph A. Regezi, DDS, MS, James J. Sciubba, DMD, PhD, Richard C.K. Jordan, DDS, MSc, PhD, FRCD(C), FRCPath