PGCEE MDS 2022 : Commonest cause of TMJ ankylosis is:

 # Commonest cause of TMJ ankylosis is:

a) Trauma

b) Development disturbances

c) Infections 

d) Atrophy

The correct answer is A. Trauma. 

The definite cause of ankylosis of TMJ is unknown. Two main factors predisposing to the ankylosis are trauma and infection in or around the joint region. In 1968, Topazian reported that 26 to 75 percent of cases of TMJ ankylosis are seen following trauma, while 44 to 68 percent are seen due to infection. 

A high percentage of TMJ ankylosis are seen following trauma. At birth, TMJ may receive trauma from a forceps delivery. Trauma during intrauterine life leads to congenital ankylosis.

PGCEE MDS 2022 MCQ: Enzymes are generally:

 # Enzymes are generally:

A. Proteins

B. Carbohydrate

C. Lipid

D. Vitamin

The correct answer is A. Proteins. 

Enzymes may be defined as biocatalysts synthesized by living cells. They are protein in nature (exception - RNA acting as ribozyme), colloidal and thermolabile in character, and specific in their action.

Nerve involved in Saturday night palsy is:

 # Nerve involved in Saturday night palsy is:

A. Radial

B. Median

C. Auxiliary

D. Facial

The correct answer is A. Radial. 

THE TERM Saturday night palsy has become synonymous with radial nerve compression in the arm resulting from direct pressure against a firm object. It typically follows deep sleep on the arm, often after alcohol intoxication. The commonly accepted origin of the phrase is the association of Saturday night with drinking alcohol heavily.

Multiple odontogenic cysts are seen in:

 # Multiple odontogenic cysts are seen in:

A. Cherubism

B. Apert’s syndrome

C. Marfan’s syndrome

D. Down’s syndrome

The correct answer is C. Marfan's syndrome.

Oral Manifestations of Marfan's syndrome

According to Baden and Spirgi, who have reviewed the oral manifestations of this disease, a high, arched palatal vault is very prevalent and may be a constant finding. Bifid uvula is also reported as well as malocclusion. In addition, multiple odontogenic cysts of the maxilla and mandible have occasionally been reported, most recently by Oatis and his coworkers. One additional finding sometimes present, is temporomandibular dysarthrosis

Right coronary artery arises from:

 # Right coronary artery arises from:

A. Anterior aortic sinus

B. Posterior aortic sinus

C. Right aortic sinus

D. Left aortic sinus

The correct answer is A. Anterior aortic sinus.

An aortic sinus is one of the anatomic dilations of the ascending aorta, which occurs just above the aortic valve. These widenings are between the wall of the aorta and each of the three cusps of the aortic valve. 

There are generally three aortic sinuses: (one anterior and 2 posterior sinus) 

• Right coronary artery arises from anterior aortic sinus of ascending aorta. 

• Left coronary artery arises from left posterior aortic sinus. 

• Right posterior aortic sinus is non-coronary sinus. 

A sphygmomanometer reading can be correct only when:

 # A Sphygmomanometer reading can be correct only when :

A. Deflation is 5-10 mm Hg per heart beat 

B. cuff is slightly full on applying to patient's arm 

C.  the cuff width is 25% of the diameter of the patient's arm 

D. length of the bladder encircle 80% of the patient's arm 

The correct answer is D. length of the bladder encircle 80% of the patient's arm.

Choosing appropriate sized cuff is vital to record accurate blood pressure in children. Small sized cuff gives elevated blood pressure readings and bigger sized cuffs give low blood pressure reading. The inflatable bladder inside the cuff should have an ideal width of at least 40% of the mid arm circumference and a cuff length that is 80 - 100% of the arm circumference. 

Nomenclature of Hand Instruments

# The shape of the shank of an instrument is described by: 

A. Class 

B. Subclass 

C. Suborder 

D. Order 

The correct answer is B. Subclass.

Dr. G.V. Black established a nomenclature for hand instruments, similar to the biological classification. 

1. Order : Purpose of instrument Eg : excavator or scaler. 

2. Suborder : Position or manner of use Eg : Push, pull 

3. Class : Form of working end, Eg : hatchet, chisel. 

4. Subclass : Shape of shank Eg : Monoangle or binangle. 

Naming usually moves from 4 to 1.