Dentosphere : World of Dentistry

 # The potency of the midazolam is: A. Thrice that of diazepam B. Twice that of diazepam C. 10 times that of diazepam D. 5 times that of diazepam The correct answer is A. Thrice that of diazepam. Midazolam This BZD is water soluble, nonirritating to veins, faster and shorter acting (t½ 2 hours) and 3 times more potent than diazepam. Fall in BP is somewhat greater than with diazepam. It is being preferred over diazepam for anaesthetic use: 1–2.5 mg i.v. followed by 1/4th supplemental doses. Also used for sedation of intubated and mechanically ventilated patients and in other critical care anaesthesia as 0.02–0.1 mg/kg/hr continuous i.v. infusion. Reference: Essentials of Medical Pharmacology, Seventh Edition, KD Tripathi, Page 383 CLICK HERE FOR MORE MCQs

 # Saliva plays a vital role in  the ________ of a complete denture. A. Retention B. Stability C. Support D. Esthetics The correct answer is A. Retention. Sufficient amount of saliva is necessary for the maintenance of oral health and comfort. In this respect, saliva is particularly important in wearers of removable dentures to protect the oral mucosa from mechanical irritation and infections and to achieve retention in complete dentures. The normal unstimulated salivary flow rate is 0.38±0.21 ml/min. Impaired salivary secretion or xerostomia is likely, if the unstimulated flow rate is less than 0.12 ml/min. Of the whole unstimulated saliva, 40 percent is derived from the submandibular glands and 8 percent from mucosal glands. The normal stimulated salivary flow rate is less than 0.60 ml/min of the whole stimulated saliva and 50 to 65 percent is derived from the parotid glands. Reference: Textbook of Complete Denture PROSTHODONTICS, Page NO. 3 CLICK HERE FOR MORE MCQs

 # Rheumatoid arthritis in children is known as: A. Still’s disease B. Kamura’s disease C. Hansen’s disease D. Degenerative joint disease The correct answer is A. Still's disease. Inflammatory arthritis occurs rarely in children. Several distinct subtypes are recognised. Systemic juvenile idiopathic arthritis (JIA; formerly known as Still’s disease) is a systemic disorder characterised by fever, rash, arthritis, hepatosplenomegaly and serositis in association with a raised ESR and CRP. Autoantibody tests are negative. Reference: Davidson’s Principles and Practice of Medicine, 22nd Edition 2014, Page no: 1104 CLICK HERE FOR MORE MCQs

# Diabetes insipidus occur due to lack of: A. Insulin B. Antidiuretic hormone C. ACTH D. Thyroxin The correct answer is B. Antidiuretic hormone. The neurohypophysis， or posterior pituitary， is formed by axons that originate in large cell bodies in the supraoptic and paraventricular nuclei of the hypothalamus. It produces two hormones: ( 1 ) arginine vasopressin (AVP)， also known as antidiuretic hormone， and (2) oxytocin. AVP acts on the renal tubulω to reduce water loss by con centrating the urine. Oxytocin stimulates postpartum milk letdown in response to suckling. A deficiency of AVP secretion or action causes diabetes insipidus (DI)，a syndrome characterized by the production of large amounts of dilute urine. Exιessive or inappropriate AVP production impairs urinary water excretion and predisposes to hyponatremia if water intake is not reduced in parallel with urine output. Reference: Harrison's Principles of Internal Medicine, 19th Edition, Page no: 2274 CLICK HERE FOR MORE MCQs

 # In jaundice there is an unconjugated hyperbilirubinemia which is most likely due to: A. Hepatitis B. Cirrhosis C. Obstruction of bile in canaliculi D. Increased breakdown of red cells The correct answer is D. Increased breakdown of red cells. Hemolysis Increased destruction of erythrocytes leads to increased bilirubin turnover and unconjugated hyperbilirubinemia; the hyperbilirubinemia is usually modest in the presence of normal liver function. In particular，the bone marrow is only capable of a sustained eightfold increase in erythrocyte production in response to a hemoIytic stress. Therefore， hemolysis alone cannot result in a sustained hyperbilirubinemia of more than -68 μmol/L (4 mg/dL) . Higher values imply concomitant hepatic dysfunction. When hemolysis is the only abnormality in an otherwise healthy individual， the result is a purely unconjugated hyperbilirubinemia，with the direct-reacting fraction as measured in a typical clinical laboratory being less or equal to 15% of ...

# Pernicious anemia is due to deficiency of: A. Iron B. Cobalamine C. Folic acid D. Niacin The correct answer is B. Cobalamine. Pernicious anemia is a relatively common chronic hematologic disease. It is an adult form of anemia that is associated with gastric atrophy and a loss of intrinsic factor production in gastric secretions and a rare congenital autosomal recessive form in which intrinsic factor (IF) production is lacking without gastric atrophy. The term pernicious anemia is reserved for patients with vitamin B12 deficiency due to a lack of production of IF in the stomach. Intrinsic factor in gastric secretions is necessary for the absorption of dietary vitamin B12. Vitamin B12, a substance now thought to be synonymous with the ‘erythrocyte-maturing factor’ or ‘hemopoietic principle’ and present in many foods, particularly liver, beef, milk and dairy products. Body stores of the vitamin usually exceed 1000 mcg and the daily requirement is about 1 mcg. Reference: Shafer’s Textboo...

 # Common site of carcinoma of tongue is: A. Apical B. Lateral borders C. Dorsum D. Posterior 1/3rd  The correct answer is B. Lateral borders. The typical lesion develops on the lateral border or ventral surface of the tongue. When, in rare cases, carcinoma occurs on the dorsum of the tongue, it is usually in a patient with a past or present history of syphilitic glossitis. In a series of 1,554 cases of carcinoma of the tongue reported by Frazell and Lucas, only 4% occurred on the dorsum. The lesions on the lateral border are rather equally distributed between the base of the tongue, the anterior third and the mid portion, although in the above series 45% of cases occurred on the middle third. Lesions near the base of the tongue are particularly insidious, since they may be asymptomatic until far advanced. Even then the only presenting manifestations may be a sore throat and dysphagia. The specific site of development of these tumors is of great significance, since the lesions...