Dentosphere : World of Dentistry

# Iron content in 3M Nickel based steel crowns is: (MAN -01) a) 20% b) 40% c) 60% d) 10% The correct answer is D. 10 %. Composition of stainless steel crowns: Stainless steel (18-8) austentic type of alloy is used. Eg.: Rocky mountain and unitek. Iron -                 87% Chromium - 17% Nickel -         12% Carbon -          0.08 - 1.15% Nickel base crowns. Eg.: Iconel 600 and 3M crowns Iron                     -  10% Chromium -    16% Nickel - 72% others - 2%

# A gingival wall is difficult to obtain in primary molar when it extends too far gingivally in class II cavities because: (MAN-97) a) Facial pulp horn may be exposed b) Inclination of cervical enamel rods occlusally c) Of marked cervical constriction d) Prime contact is broad and flat The correct answer is C. of marked cervical constriction. Gingivally the enamel rods have an occlusal direction in primary teeth so bevel is not required as there will be no unsupported enamel rods. It is difficult to obtain gingival wall when lesion extends too far gingivally in primary molar due to the presence of marked cervical constriction.

# Dose adjustment of all of the  following drugs will be required in a patient with severe liver cirrhosis EXCEPT: a) Lorazepam b) Theophylline c) Paracetamol d) Metronidazole The correct answer is A. Lorazepam. PHARMACOKINETICS Most of the BZDS are metabolized in the liver to produce active products (thus long duration of action). Active metabolites may result in cumulative effects. After metabolism, these are conjugated and are excreted via kidney. Estazolam, lorazepam, oxazepam, temazepam and triazolam are directly conjugated without metabolism to active products. These drugs are thus short-acting and do not accumulate on repeated administration. Further these drugs can be safely administered in liver failure and in elderly because these are conjugated directly without undergoing metabolism in the liver. (Mnemonics: @  TO-LET ; Short-acting drugs are T riazolam, O xazepam, L orazepam, E stazolam and T emazepam,). Compounds with shorter half life are...

# Of the following local anesthetics, which has intrinsic vasoconstrictive action? (MAN -97) a) Cocaine b) Procaine c) Xylocaine d) Bupivacaine The correct answer is : A. Cocaine All local anaesthetics except cocaine are synthetic compounds and they are vasodilating in nature. Cocaine is a natural local anaesthetic agent and causes local vasoconstriction.  (Cocaine increases the vasoconstrictive action of adrenaline. If LA with adrenaline is given risk of death is more in cocaine abusers. So they are known as   'walking time bombs.'

# Which of the following is the preferred local anesthetic technique for hemophilics? (MAN -01) a) Nerve block b) Supraperiosteal c) Intraligamentary d) Field block The correct answer is C. Intraligamentary.  In hemophilics to avoid complications,  Intraligamentary  (an intraosseous technique) method of local infiltration technique is preferred. In this technique, the solution is deposited in depth of gingival sulcus. The needle should be inserted apically into the bone until resistance is met.

# Which of the following may least be used as an abutment: (PGI -2K) a) Tooth with minimum crown b) Tooth with short tapered crown and conical roots c) Rotated and tipped tooth d) Pulp treated tooth The correct answer is: B. b) Tooth with short tapered crown and conical roots Reply Forward

# Epitheloid cells are seen in all of the following except (MAN -02): a) Tuberculosis b) Granulation tissue c) Syphilis d) Sarcoidosis The correct answer is : B. Granulation Tissue Epitheloid cells are a collection of modified macrophages present in granuloma. Granulomas occur in Tuberculosis, Leprosy, syphilis, Actinomycosis, Sarcoidosis, etc.