AIPGEE 1 Explanation

8/8/2019 AIPGEE 1 Explanation

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1 4 SAT-1 51 1 SAT-8 101 1 SAT-15 151 1 SAT-222 4 SAT-1 52 3 SAT-8 102 2 SAT-15 152 2 SAT-223 2 SAT-1 53 2 SAT-8 103 3 SAT-15 153 1 SAT-224 3 SAT-1 54 4 SAT-8 104 3 SAT-15 154 1 SAT-225 1 SAT-1 55 2 SAT-8 105 3 SAT-15 155 1 SAT-236 4 SAT-1 56 1 SAT-8 106 1 SAT-16 156 4 SAT-237 4 SAT-1 57 3 SAT-9 107 1 SAT-16 157 2 SAT-238 1 SAT-2 58 1 SAT-9 108 1 SAT-16 158 3 SAT-239 2 SAT-2 59 4 SAT-9 109 2 SAT-16 159 4 SAT-230 3 SAT-2 60 2 SAT-9 110 2 SAT-16 160 4 SAT-231 1 SAT-2 61 4 SAT-9 111 3 SAT-16 161 4 SAT-232 4 SAT-2 62 2 SAT-9 112 1 SAT-16 162 3 SAT-243 1 SAT-2 63 2 SAT-9 113 4 SAT-17 163 1 SAT-244 1 SAT-2 64 3 SAT-10 114 3 SAT-17 164 1 SAT-245 3 SAT-3 65 2 SAT-10 115 1 SAT-17 165 2 SAT-246 2 SAT-3 66 2 SAT-10 116 3 SAT-17 166 2 SAT-247 2 SAT-3 67 4 SAT-10 117 2 SAT-17 167 2 SAT-248 3 SAT-3 68 3 SAT-10 118 3 SAT-17 168 3 SAT-249 1 SAT-3 69 1 SAT-10 119 4 SAT-17 169 4 SAT-25

0 4 SAT-3 70 3 SAT-10 120 4 SAT-18 170 4 SAT-251 3 SAT-3 71 1 SAT-11 121 4 SAT-18 171 1 SAT-252 4 SAT-4 72 3 SAT-11 122 2 SAT-18 172 3 SAT-253 2 SAT-4 73 4 (1 & 3) SAT-11 123 1 SAT-18 173 3 SAT-254 4 SAT-4 74 4 SAT-11 124 3 SAT-18 174 4 SAT-255 1 SAT-4 75 1 SAT-11 125 4 SAT-18 175 3 SAT-256 1 SAT-4 76 1 SAT-11 126 1 SAT-18 176 3 SAT-267 3 SAT-4 77 4 SAT-11 127 4 SAT-19 177 2 SAT-268 2 SAT-4 78 2 SAT-12 128 2 SAT-19 178 3 SAT-269 1 SAT-5 79 2 SAT-12 129 4 SAT-19 179 4 SAT-260 2 SAT-5 80 4 SAT-12 130 3 SAT-19 180 3 SAT-261 1 SAT-5 81 1 SAT-12 131 4 SAT-19 181 4 SAT-262 2 SAT-5 82 1 SAT-12 132 3 SAT-19 182 2 SAT-26

3 2 SAT-5 83 1 SAT-12 133 4 SAT-19 183 1 SAT-274 3 SAT-5 84 4 SAT-12 134 3 SAT-20 184 3 SAT-275 2 SAT-5 85 1 SAT-13 135 3 SAT-20 185 3 SAT-276 4 SAT-6 86 3 SAT-13 136 4 SAT-20 186 4 SAT-277 4 SAT-6 87 2 SAT-13 137 3 SAT-20 187 2 SAT-278 4 SAT-6 88 3 SAT-13 138 4 SAT-20 188 3 SAT-279 2 SAT-6 89 3 SAT-13 139 3 SAT-20 189 3 SAT-270 2 SAT-6 90 1 SAT-13 140 4 SAT-20 190 1 SAT-281 3 SAT-6 91 1 SAT-13 141 2 SAT-21 191 2 SAT-282 2 SAT-6 92 4 SAT-14 142 2 SAT-21 192 1 SAT-283 2 SAT-7 93 1 SAT-14 143 4 SAT-21 193 4 SAT-284 3 SAT-7 94 3 SAT-14 144 3 SAT-21 194 4 SAT-285 3 SAT-7 95 1 SAT-14 145 4 SAT-21 195 2 SAT-286 1 SAT-7 96 4 SAT-14 146 3 SAT-21 196 2 SAT-297 1 SAT-7 97 3 SAT-14 147 2 SAT-21 197 4 SAT-298 2 SAT-7 98 2 SAT-14 148 1 SAT-22 198 2 SAT-299 2 SAT-7 99 2 SAT-15 149 4 SAT-22 199 2 SAT-290 1 SAT-8 100 3 SAT-15 150 2 SAT-22 200 3 SAT-29


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Ans.1Piloerection is not important in human beings. It means hairs standing on end. Sympathetic stimulation causes the arrector pmuscles attached to the hair follicles to contract which brings the hairs to an upright stance. This is not important in human beings bin lower animals, upright protections of hairs allows them to entrap a thick layers of insulator air next to the skin, so that transferheat to the surroundings is greatly depressed.Temperature increasing mechanisms (when the body is too

cold)

Temperature decreasing mechanisma (when the body is

too hot)

- vasoconstriction of skin blood vessels (stimulation ofposterior hypothalamic sympathetic centers)

-

Increase in thermogenesis (heat production).- Enhanced shivering, thyroxine secretion, Sympatheticexcitation of heat production

- Piloerection: (conserve heat) not important in humanbeings, important in lower animals.

- Vasodilatation of skin blood vessels.(inhibition ofposterior hypothalamic sympathetic centers)

-

Decrease in thermogenesis (heat production)-inhibitionof shivering, inhibition of chemicakl thermogenesis.- Sweating: (heat loss)- evaporative heat loss.

Ans.2Massage and the application of liniments to painful area relieves pain due to inhibition of pain pathway in the dorsal horn gate stimulation of large diameter touch pressure afferent fibers.Touch and pressure is carried by A sensory fibers and pain is carried by Aand C type fibers. The diameter of A > A > C.Many people have learned from practical experience that touching or shaking an injured area decrease the pain of injury. Tlaminiscal fibers carrying tactile senses give collaterals to pain carrying afferent nerve fibers. When leminiscal fibers are stimulated tactile sensation they cause presynaptic inihibitionQ on the primary pain carrying afferent and pain is inhibited.

Ans.3Hypothalamic regulation of the apetite for food depends primarily on the interaction of two areas: a lateral feeding center in the bnucleus of the medial forebrain bundle at its junction with the pallidohypothalamic fibers, and a medial satiety center in tventromedial nucleus. Stimulation of the feeding center evokes eating behavior in conscious animals, and its destruction caussevere, fatal anorexia in otherwise healthy animals. Stimulation of the ventromedial nucleus causes cessation of eating, wherelesions in this region cause hyperphagia and, if the food supply I abundant, the syndrome of hypothalamic obesity.

Ans.4Compliance of lung is a measure of stretchability of lungs and hence its total capacity. It is the change in lung volume per unit chanin air way pressure (V/P).Lung Compliance is increased in emphysemaLung compliance decreased in-- Deformities of thorax eg- kyphosis, scoliosis.- Paralysis of respiratory muscles.- Pleural effusion.- Abnormal thorax eg- pneumothorax, hydrothorax, hemothorax.- Interstitial pulmonary fibrosis.- Interstitial lung disease.- Pulmonary congestion.Ans.5Deoxygenated hemoglobin binds more H+ than oxyhemoglobin does and forms carbamino compounds more readily, binding oxygen to hemoglobin reduces its affinity for carbon dioxide (Haldane effect). Consequently, venous blood carries more carbdioxide than arterial blood, carbon dioxide uptake is facilitated in the tissues, and CO2 release is facilitated in the lungs. About 11%the CO2 added to the blood in the systemic capillaries is carried to the lungs as carbamino CO2.

Ans.6The overall blood flow in circulation of adult at rest is about 5 liter/ minute which equals to cardiac output because it is the amount blood pumped by heart per unit time. SoBlood pressure = Cardiac output X peripheral resistance or blood flow (Q) X resistance Venous return = MSFP-RAP/RVRWhere, MSFP = Mean systemic filling pressureRAP = Right atrial pressureRVR = Resistance to venous return.


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Ans.8Sources of digestive enzymes-

- Salivary gland- alpha amylase- Lingual glands- lipase- Stomach- Pepsinogen and lipase- Cytoplasm of mucosal cells- peptidase- Intestinal mucosa- Enteropeptidase,

Aminopeptidase, Carboxypeptidase,Endopeptidase, Dipeptidase, Maltase,Lactase, Sucrase, alpha dextrinase,trehalase, nuclease.

Exocrine pancreas- Trypsin, Chymotrypsin, elastase, pancreatic lipase,bile salt acid lipase, colipase, cholestery ester hydrolasePancreatic alpha amylase, carboxy peptidase A and B, Phospholipase A2,Ribonuclease, Deoxyribonuclease.

Ans.9Pancreatic juice is essentially alkaline with a pH as high as 8.0 to 8.3Intestinal juice pHSalivaGastric juicePancretic juiceBile

6.0 to 7.01.0 to 3.58.0 to 8.37.8

Ans.11Negatively charged large molecules are filtered less easily than positively charged molecules of equal molecular size, and even neutmolecule are filtered much more easily than negatively charged molecules of same size. This is because, the negative charges basement membrane and podocytes restrict and repel large negatively charged and attract positively charged molecules. This explaionly 0.2% filterability of negatively charged albumin with an effective diameter of ~ 7 nm.Inulin (a polymer of fructose) that is freely filtered, neither reabsorbed nor secreted in tubules, and creatinine (that is freely filteresecreted and reabsorbed in some amount) are used to measure glomerular filtration rate (GFR).

Ans.12The sertoli cells secrete androgen bonding protein (ABP), inhibin, and MIS i.e. Mullerian inhibiting substance. Sertoli cells hareceptors for FSH and testosterone. After combining with FSH, sertoli cells stimulate the first half of spermatogenesis. Subsequentestosterone- sertoli cells binding causes development of last half of spermatogenesis.

Ans.13Oxytocin causes contraction of the myoepithelial cells lining the duct walls, with consequent ejection of the milk through the nippThe reflex release of oxytocin initiated by touching the nipples and areolas (milk ejection reflex).

Suckling not only evokes reflex oxytocin release and milk ejection; it also maintains and augments the secretion of milk becausethe stimulation of prolactin secretion produced by suckling.Oxytocin also cause contraction of smooth muscles of the uterus.

Ans.14The sequence of cell cycle is-G0 phase- Quiscent cells are in G0 phase or resting phase.G1 phase (12 hrs)-presynthetic phase.S phase(6 to 8 hrs)- DNA synthesis phase.G2 phase (4 to 5 hrs)- (premitotic phase) cytoplasmic enlargement; preparation for cell division; DNA repair can occur.M phase- Mitotic phase.

Ans.15

Chemical mediators of Inflammation1. Preformed mediator in secretory granules : Histamine

: Serotonin: Lysosomal enzyme

2. Newly synthesized : Prostaglandin leukotrienes, platelet activating factors: Activated oxygen species: Nitric oxide: Cytokines

* Tumor necrosis factor * Interleukin 1


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3. Factor XII activation : - Kinin system (bradykinin): - Coagulation / fibrinolysis system

4. Complement activation : - C3aAnaphylatoxin

C5aC3bC5b-9 (membrane attack complex)

Ans.16

Leukotrienes (LT) or slow-reacting substances of anaphylaxis (SRS-As) are so named as they were first isolated from leucocyteFirstly, unstable leukotriene A4 (LTA4) is formed which is acted upon by enzymes to form LTB4 (chemotactic for phagocytic cells astimulates phagocytic cell adherence) while LTC4, LTD4 and LTE4 have common actions by causing smooth muscle contraction athereby induce vasoconstriction, bronchoconstriction and increased vascular permeability.C5a is chemotatic for leucocytes.

Ans.17Mucus cyst of the mouth is a retention type of cyst resulting from blockage or rupture of salivary gland duct. It is most often found the lower lip as a result of trauma.

Ans.18In chronic venous congestion liver, the centre of liver lobule is tan brown with surrounding zones of uncongested liver. Thappearance is called nutmeg liver. Microscopically, there is centrilobular coagulative necrosis with haemorrhage accompanied periportal fatty change.

Ans.19Necrosis is defined as focal death along with degradation of tissue by hydrolytic enzymes liberated by cells. It is invariabaccompanied by inflammatory reactionNecrosis can be caused by various agents such as hypoxia, chemical and physical agents, microbial agents and immunological injuTwo essential changes bring about irreversible cell injuries in necrosis- cell digestion by lytic enzymes and denaturation of proteiThese processes are morphologically identified by characteristic cytoplasmic and nuclear changes in necrotic cell. The cytoplaappears homogeneous and intensely eosinophillic. Occasionally, it may show vacuolation or dystrophic calcification. The nuclechanges include condensation of nuclear chromatin (pyknosis) which may either undergo dissolution (karyolysis) or fragmentatiinto many granular clumps (karyorrhexis).

Ans.20Leprosy has two different patterns of disease. One is characterized by tuberculosis leprosy with effective cell mediated immuni

asymmetric peripheral nerve involvement and presence of well defined granulomas at lesional site. Other pattern is lepromatoleprosy characterized by defective immunity, symmetric skin thickening and nodules and presence of large collections of lipid ladmacrophages (Virchows lepra cells) filled with aggregates of acid fast bacilli (globi) at lesional site. These lesions are infections amay lead to leonine facies. Granulomas are absent from lesional site.

Ans.21A particular form of gas embolism, called decompression sickness, occurs when individual are exposed to sudden changesatmospheric pressure. A more chronic form of decompression sickness is called Cassion disease, where persistence of gas embolithe bones leads to multiple foci of ischemic necrosis; the heads of the femurs, tibias, and humeri are most commonly affected.

Ans.22The diagnosis of Hodgkins disease rests on identification of RS cells, though uncommonly similar cells can occur in infectiomononucleosis and other forms of lymphomas. Therefore, additional cellular and architectural features of the biopsy must be giv

due consideration for making the histologic diagnosis.1. Classic RS cell is a large cell which has characteristically a bilobed nucleus appearing as mirror image to each other boccasionally the nucleus may be multilobed.

2. Lacunar type RS cell is smaller and in addition to above features has a pericellular space or lacuna in which it lies, whichdue to artefactuals shrinkage of the cell cytoplasm. It is characteristically found in nodular sclerosis variety of HD.

Ans.23Laboratory diagnosis of hypochromic anemiasTest Iron deficiency Chronic disorders Thalassemia Sideroblastic anemia1.MCV, MCH, MCHC Reduced Low normal to reduced Very low Very low (except MCV raised i


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acquired type)2. Serum iron Reduced Reduced Normal Raised3. TIBC Raised Reduced Normal Normal4. Serum ferritin Reduced Raised Normal Raised (complete saturation)5. Marrow iron stores Absent Present Present Present6.Iron in normoblasts Absent Absent Present Ring sideroblast7.Hb elctrophoresis Normal Normal Abnormal NormalIn megaloblastic anemia-There is rise in serum unconjugated bilirubin and LDH as a result of ineffective erythropoiesis causing marrow cell break down.

The serum iron and ferritin may be normal or elevated.

Ans.24Prothrombin time depends on factor II, VII, IX and X. the synthesis of these factors depends on vitamin K. Vitamin K deficienoccurs in liver disorder as well as in obstructive jaundice or fat malabsorption of any kind.

Ans.25Amoebiasis is caused by Entamoeba histolytica, named for its lytic action on tissues. It is the most important intestinal infection man.The parasite occurs in 2 forms: a trophozoite form which is active adult form seen in the tissues and diarrhoeal stools, and a cysform seen in formed stools but not in the tissues.The lesions of amoebiasis include amoebic liver abscess and spread to other sites.Amoebic colitis, the most common type of amoebic infection begins as a small area of necrosis of mucosa which may ulcerate. Theulcerative lesions may enlarge, develop undermining of margins of the ulcer due to lytic action of the trophozoite and have necrotbed. Such chronic amoebic ulcers are described as flask shaped or bottle mouth shaped ulcers due to their shape. The margin of tulcer shows inflammatory response consisting of admixture of polymorphonuclear as well as mononuclear cells.

Ans.26SLE is a multisystem autoimmune disease of protean manifestations. Immunologically the disease is associated within enormous arrof autoantibodies, classically including anti nuclear antibodies (ANAs). ANAs are directed against several nuclear antigens-

- Antibodies to dsDNA (The most specific test).- Antibodies to histones.- Antibodies to non histone proteins bound to RNA.- Antibodies to nuclear antigens (The most sensitive test).

Ans.27Gauchers disease results from mutation in the gene that encodes glucosylceramidase. There are five Autosomal recessive variants

Gaucher disease resulting from distinct allelic mutations. Common to all is variably deficient activity of a glucosylceramidase thnormally cleaves the glucose residue from ceramide. This leads to an accumulation of glucosylceramide in the mononuclephagocytic cells and their transformation into so called Gaucher cells.

Ans.28Hairy cell leukemia (HCL), is an unusual and uncommon form of chronic leukemia in which there is presence of abnormmononuclear cells with hairy cytoplasmia projections in the bone marrow, peripheral blood and spleen.These leukemic hairy cells have characteristically positive cytochemical staining for tartarate resistant acid phosphatase. Tcontroversy on the origin of the hairy cells whether these cells represents neoplastic T cells, B cells or monocytes, is settled with tmononuclear analysis of these cells which assigns them B cell origin expressing CD19, CD20 and CD22 antigen. In addition to B cmarkers, hairy cells are also positive for CD11, CD25 and CD103.

Ans.29

Characters Gram positive Gram negativeThicknessVariety of amino acidsAromatic and sulphur containing amino acidsLipidsTeichoic acid

ThickerFewAbsentAbsent or scantPresent

ThinnerSeveralPresentPresentAbsent


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Ans.30The milk is heated at either 63 degree C for 30 minutes (the holder method) or 72 degree C for 15 to 20 seconds (the flash procesfollowed by cooling quickly to 13 degree C or lower. By these processes all non sporing pathogens such as mycobacteria, bruceland salmonellae are destroyed. Coxiella burnetti is relatively heat resistant and may survive the holder method.

Ans.31Chemical disinfectants which can be safely applied to skin or mucus membrane and are used to prevent infection by inhibiting tgrowth of bacteria are called antiseptics.

Ans.32Mycoplasmas are a group of bacteria that are devoid of cell walls and so are highly pleomorphic, with no fixed shape or size. Thlack even cell wall precursors like muramic acid or diaminopimelic acid. The cells are bounded by a soft trilaminar unit membracontaining sterols. Because of their plasticity, they can pass through bacterial filters and have often been mistaken for viruses.

Ans.33Phagocytic cells are the mononuclear macrophages (of blood and tissue) and the polymorphonuclear microphages.The primary function of macrophages is phagocytosis.

Ans.34Haptens are substances which are incapable of inducing antibody formation by themselves but can react specifically with antibodiesHaptens may be complex or simple; while complex haptens can precipitate with specific antibodies, simple haptens are nprecipitating. They can inhibit precipitation of specific antibodies by the corresponding antigens or complex hapten.

Ans.35The major clinical features of the GVH reaction in animals are retardation of growth, emaciation, diarrhoea, hepatosplenomegallymphoid atrophy and anemia, terminating fatally. The syndrome has been called runt disease.

Ans.36Pfieffer (1894) discovered that cholera vibrios were lysed when injected intraperitoneally into specifically immunized guinea pi(bacteriolysis in vivo or pfieffers phenomenon). Bordet (1895) extended these observations and established that immune bacteriolyand hemolysis required two factors- the heat stable antibody and a heat labile factor, which was called alexine. This term has bereplaced by the present name complement which was coined by Ehrlich, because this factor complemented the action of antibody.

Ans.37The antibody formed in the primary response is predominantly IgM and in the secondary response IgG. The early antibody is mospecific but less avid then the late antibody.

Ans.38Transcobalamin II deficiency is inherited as autosomal recessive patients show metabolic effects of vitamin B12 deficiency includimegaloblastic anemia and intestinal villous atrophy. The associated immunological defects are depleted plasma cells, diminishimmunoglobulin levels and impaired phagocytosis. Treatment with vitamin B12 has been reported to restore hematopoietgastrointestinal and B cell functions but not phagocytic activity.

Ans.39In HIV the genome is diploid, composed of two identical single stranded, positive sense RNA copies. In association with viral RNAthe reverse transcriptase enzyme, which is a characteristic feature of retroviruses.

Ans.40AIDS in the developing countries differs from the disease in the western countries clinically too. In Africa, the major manifestation

pronounced wasting so that it has been called the slim diseaseAns.41Congenital or vertical transmission is quite common from carrier mothers. The risk to babies is high if the mother is HBsAg positi(10 to 90%) and low if negative (5 to 15%).

Ans.42HBV is a 42 nm DNA virus with an outer envelop and an inner core, 27 nm in diameter, enclosing the viral genome and a DNpolymerase.


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Ans.43Properties of choline esters.

Choline ester Hydrolysis by Ach E BuChE Actions Musc. Nico Selective action on

Acetylcholine ++ + + + Non selectiveMethacholine + - + CvsCarbachol - - + + g.i.t., bladderBethanechol - - + - g.i.t., bladder

Amongst given options carbactol has maximum nicotinic action. It has both nicotinic as well as muscarinic actions. All other drugs have muscarinic actions.

Cholinomimetic drugs

With Muscarinic actions With Nicotinic actions

a) Acetylcholine a) Acetylcholineb) Methacholine b) Carbacholc) Carbactol c) Arecholined) Bethanectole) Pilocarpinef) Muscarineg) Arecholine

Ans.44

Contraindications - Atropinic drugs are absolutely contraindicated in individuals with a narrow iridocorneal angle may precipitacute congestive glaucoma. However, marked rise in intraocular tension is rare in patients with wide prostatic hypertrophy urinretention can occur.

Ans.45Classification Nonselective (1 and 2)

a) Without intrinsic sympathomimetic activity Propranolol, Sotalol, Timolol.b) With intrinsic sympathomimetic activity Pindolol.c) With additional a blocking property Labetalol, Carvedilol.

Cardioselective (1)Metoprolol, Atenolol, Acebutolol, Bisoprolol, Esmolol, Betaxolol, Celiprolol.

Ans.46

Heart Ppnl decreases heart rate, force of contraction (at relatively higher doses) and cardiac output (c.o.).Heart - The most prominent effect of atropine is to cause tachycardia.Heart- Adr increases heart rate by increasing the slope of slow diastolic depolarization of cells in the SA node.- CVS Methylxanthines directly stimulate the heart and increase force of myocardial contractions. They tend to increase heart rby direct action, but decrease it by causing vagal stimulation.- Aminophylline is a methylxanthine.

Ans.47Interactions

1) Alcohol synergises with tranquilizers, antidepressants, antihistaminics, hypnotics, opioide marked CNS depression wmotor impairment can occur: Chances ofaccidents increase.

2) Sulfonylureas (specially chlorpropamide), certain cephalosporins (cefoperazone, moxalactam, cefamandole) ametronidazole: individuals on these drugs have experienced bizarre, someshat disulfiram like reactions when thy consumalcohol.

3) Acute alcohol ingestion inhibits, while chronic intake induces tolbutamide, phenytoin (and many other drugs) metabolism.4) Insulin and sulfonylureas; alcohol enhances hypoglycaemia acutely.5) Aspirin causes more gastric bleeding when taken with alcohol.6) Alcoholics are more prone to paracetamol toxicity due to enhanced generation of its toxic metabolite.

Ans.48 Tolerance is exhibited to most actions of morphine except for miosis and constipation. Morphine is a centrally acting analgesic. It has site specific depressant and stimulant action in CNS. Morphine produces pronounce psychological and physical dependence. Its abuse liability is very high.


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Ans.49I. BronchodilatorsA. Sympathomimetics: Adrenaline, Ephedrine, Isoprenaline, Salbutamol, Terbutaline, Bambuterol, Salmeterol, Formoterol.B. Methylxanthines: Theophylline (anhydrous), Aminophylline, Choline theophyllinate, Hydroxyethyl theophylli

Theophylline ethanolate of piperazine.C. Anticholinergics: Atropine methonitrate, Ipratropium bromide, Tiotropium bromide.II. Leukotriene antagonists

Montelukast, Zafirlukast.

III.Mast cell stabilizersSodium cromoglycate, Nedocromil, Ketotifen.

IV. CorticosteroidsA. Systemic: Hydrocortisone, Prednisolone and others.B. Inhalational: Beclomethasone dipropionate, Budesonide, Fluticasone propionate, Flunisolide. Organophosphates have cholinergic action, can cause exacerbation of asthma.

Ans.50 Pharmacokinetics is the quantitative study of drug movement in, through and out of the body. Study of drug effect is Pharmacodynamics

DISTRIBUTION Pharmacokinetics

ELIMINATION

Pharmacologic effect Pharmacodynamics

Clinical response

>Toxicity EfficacyRemember

Pharmacodynamics (D) Drug does to body Pharmacokinetics Body does to drug.

Ans.51 Specificity refers to the ability of a drug to bind specific receptor and produce a selective action so that side effects do n

occur. High specificity decreases the side effects. the pharmacologist who produces a new drug and the doctor who gives, it to a patient share the desire that it should posse

a selective action, so that additional and unwanted adverse effects do not complication the management of the patientSo side effects of drugs which arise due to interaction of the drug to molecules other than the target can be minimized making the drug more specific.

Ans.52 Chloroquine is a safe antimalarial drug for pregnant women. Safe drugs for pregnant women :

Chloroquine Spiramycin Methyldopa

Dose of drug

administered

Drug concentration insystemic circulation Drug in tissues of distribution

Dru metabolized or excretedDrug concentration at

site of action


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Hydralazine Zidovudine Labetalol Heparin Prazosin ClonidineNote -Propylthiouracil is not safe during pregnancy but it is the DOC for thyrotoxicosis in pregnancy.

Ans.53The anticancer antibiotics are :

- Actinomycin D (Dactinomycin) - Daunorubicin (Rubidomycin) - Mitomycin C- Doxorubicin -Mitoxantrone - Mithramycin (plicamycin)-

Bleomvcins These anticancer, antibiotics obtained from micro-organisms and have prominent antitumour activity. Mechanism of action:

They intercalated between DNA strands and interfere with its template function.Actinomycin D inhibits DNA dependent RNA synthesis.Bleomycin cause DNA breakage and free radical formation.Doxo-and daunorubicin inhibit Topoisomerase I & II.Mitomycin acts like alkylating agents.Mitoxantrane binds to DNA to produce strand breakage and inhibits both DNA & RNA synthesis.

Ans.54 Amongst the given optins pefloxacin causes phototoxicity.Adverse effects1. GI distrurbance Nausea, Vomiting, Bad taste, anorexia (most common).2. CNS Dizziness, headache, restlessness, anxiety, insomnia, tremor, seizures due to GABA antagonistic action.3. Cartilage damage in weight bearing joints Contraindicated in children.4. Tendonitis and tendon rupture.5. Skin/hypersensitivity Rash, pruritis, urticaria.6. Phototoxicity by lomefloxacin (maximum), sparfloxacin and pefloxacin.7. Sparfloxacin, Gatifloxacin and moxifloxacin can prolong QT interval (Torsades de pointes).Note Following FQs have been withdrawn from the market because of their rare but potentially fatal side effec

(Goodman & Gilman 11th/e 1119)

Temafloxacin Immune hemolytic anemia Trovafloxacin Hepatotoxicity Grepafloxacin Cardiotoxicity Clinafloxacin Phototoxicity

Ans.55The carbapenem imipenem has excellent activity against methicillin-sensitive S.aureus but not MRSA.MRSA is resistant to all -lactam antibiotics because resistanec develops due to alteration in transpeptidase (penicillin bindiprotein) on which all -lactam antibiotics act.Drugs for MRSA

Ans.56 Antitubercular drugs

First line Isoniazid, rifampin, ethambutol, streptomycin, pyrazinamide.Second line Thiacetazone, PAS, ethionamide, cycloserine, Kanamycin, amikacin, capreomycin, ciprofloxaci

ofloxacin, clarithromycin, Azithromycin, rifabutin. Tobramycin is not an antitibercular aminoglycoside.

Ans.57Causes of iron deficiency anemia

Vancomycin (DOC)TMP-SMXMinocyclin

CiprofloxacinLinezolidLevofloxacin

Quinopristin /dalfopristinDaptomycinOritavaccin

Tigecyclin

DietMalabsorption


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The indices of the patient in question suggesdiagnosis of Microcytic Hypochromic anemThe single best cause for his anemia isHookworm infection which causes an ir

deficiency anemia due to persistagastrointestinal blood loss.

Ans.58The most common mutation in beta thalassemia involves the intervening sequence 1 (IVS-1) or the intron-1

Mutations in Beta Thalassemia Most types of Beta thalassemia are caused by point mutations affecting one of few bases. A given mutation usually occurs within only one racial group and within a given racial group, five or six specific mutatio

usually accounts for more than 90% of cases of Beta-thalassemia. The most common site of mutations in Beta thalassemia is the intervening sequence 1 (IVS-1) or Intron 1.Ans.59

Bone marrow transplantation is the best therapy for the young patient with a fully histocompatible sibling donor.The curative treatment for young (< 20 year-old) patients with severe idiopathic aplastic anemia is allogenic bone marrtransplantation if there is an available donor. Those with a compatible sibling donor should proceed to transplantation as soonpossible.

Ans.60In dentistry Surgery, General Anaesthesis is contraindicated in patients with Hemophilia

Ans.61Pernicious aneia is characterized by autoimmune destruction of parietal cells leading to hypochondria ( acid production). It is associated with peptic ulcer disease.

Aetiological Factors in peptic ulceration

Primary Aetiological Factors (selected) Endocrinal Disorders- MEN- Primary Hyperparathyroidism- Zollinger Ellison SyndromeQ- Cushings syndrome CirrhosisQ Chronic Renal Failure

AchlorhydriaChronic, atrophic gastritis- Gastric resection and bypass- Vagotomy- Intestinal bypass operations- Celiac disease (= nontropical spru- Tropical sprueIncreased iron requirements

- Pregnancy and lactation

- Growth

Blood Loss

Gastrointestinal bleeding- Hemorrhoid- Angiodysplasia of the colon- Hereditary, hemorrhagic, teleangiectasia- Syndrome (Oster-Weber-Rendu- Syndrome)-

Peptic ulcer- Nonsteroidal, anti-inflammatory drugs- Oral anticoagulation- Hiatal hernia- Meckel diverticulum- Diverticulosis of the colon- Intestinal polyps- Carcinoma- Inflammatory bowel disease- Hookworm: Nector Americanus.- Ancylostoma duodenale

Shistosoma: S Mansoni,S. hematobium

- Trichuris

Menstruation Frequent blood donations Erythrocyturia: bladder

neoplasm Hemoglobinuria- Paroxysmal, nocturnal

hemoglobinuria- Erythrocytefragmentation inprosthetic heart valves

Factitious anemiaIntravenous and intraarterial drug abuse

Hemodialysis Nosocomial blood loss

due to frequentvenisection


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Primary Aetiological Factors (selected) H. pylori infection NSAIDs and other drugs eg. Steroids Stree Head injury / Burns Bile Reflus Smoking / Alcohol use Genetic Factors

Chronic Pulmonary Disease Chronic Paracreatic Disease Alpha l Antitrypsin deficiency

Ans.62Hydrochlorthiazide is not a preferred agent for the treatment of hypertension in diabetics as it causes unfavourable alteration glucose and lipid profile of the patient.Hyperglycemia and hyperlipidemia have been reported with the used of diuretics as antihypertensives KDT

Antihypertensive drugs in diabetics:ACE inhibitors or angiotensin receptor blockers are the first line agents for management of hypertension in diabetics Harrison 1/ 1479Lisinopril & Trandalopvil are examples of ACE inhibitors while Losartan is an angiotensin receptor blocking agent.These have no known adverse effects on glucose or lipid metabolism and minimize the development of diabetic nephropathy reducing renal vascular resistance and renal perfusion pressure.

What puzzles the situation:

In Diabetic patient with hypertension multiple agents are usually neede to achieve good blood pressure control. The average diabepatient will require at least three medications to achieve appropriate control. While ACE inhibitors/angiotensin receptor blockers wform an essential component of the regimen. Thiazide diuretics may also be used as an additional agent. Thus diuretics though preferred agents for treatment of hypertension in diabetics, may well be used as conjunctive agents and are a possible treatmemodality. Nevertheless they are the single best answer to exclude amongst the options provided here.

Ans.63IgM and IgG fix complement via the classical pathwayFrequently asked questions on immunoglobulins:

Immunoglobulin to fix complements via classical pathway IgG & IgM (IgM > IgG)Q Immunoglobulin to fix complements via alternative pathway IgAQ & IgDQ Immunoglobulin with maximum serum conc. IgGQ Immunoglobulin with minimum serum conc. IgEQ Immunoglobulin that in heat labile IgEQ Immunoglobulin in primary immune response IgMQ Immunoglobulin in secondary immune response IgGQ Immunoglobulin with maximum molecular weight IgMQ Immunoglobulin present in milk IgAQ & IgGQ Immunoglobulin with maximum sedimentation coefficient IgMQ Immunoglobulin with shortest life IgEQ Immunoglobulin in seromucinois glands IgG & IgAQ Immunoglobulin resp. for hypersensitive pneumonitis IgGQ Immunoglobulin mediating the prausnitz Kustner reaction IgEQ Homocytotropism is seen in which Ig IgEQAns.64

The enzyme enolase requires Mg2+ or Mn2+ as a cofactor and it is inhibited by fluoride. Thats why for blood glucose estimation in tlaboratory, fluoride is added to the blood to prevent glycolysis by the cells, so that the blood glucose is correctly estimated.

Ans.65Glycogen is the major storage carbohydrate in animals, corresponding to starch in plants; it is a branched polymer of alpha D-glucosIt occurs mainly in liver (up to 6%) and muscle, where it rarely exceeds 1%. However, because of its greater mass, muscle containsabout three to four times as much glycogen as does liver. Muscle glycogen is a readily available source for glycolysis within themuscle itself.

Ans.66


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The steroid nucleus (ring structure) of the cholesterol cannot be degraded to CO2 and H2O. Cholesterol (50%) is converted to bacids, excreted in feces, serves as a precursor for the synthesis of steroid hormones, vitamin D, coprostanol and cholesatnol. The lattwo are the fecal sterols, besides cholesterol.

Ans.67Fatty liver occurs during starvation and the feeding of high fat diets. The ability to secrete VLDL may also be impaired. uncontrolled diabetes mellitus, twin lamb disease, and ketosis in cattle, fatty infiltration is sufficiently severe to cause visible pal(fatty appearance) and enlargement of the liver with possible liver dysfunction.

Ans.68Glutamate rapidly undergoes oxidative deamination, catalyzed by glutamate dehydrogenase (GDH) to liberate ammonia. It is themajor source of NH3 in kidney. This enzyme is unique in that it can utilize either NAD

+ or NADP+ as coenzyme.Ans.69Heme biosynthesis occurs in most mammalian cells with the exception of mature erythrocytes, which do not contain mitochondria.However, approximately 85% of heme synthesis occurs in erythroid precursor cells in the bone marrow and the majority of theremainder in hepatocytes.

Ans.70The main examples of defense proteins are snake venoms and immunoglobulins.

Ans.71Ingestion of water is mainly controlled by the thirst center locate in the hypothalamus.

Ans.72Na+ is the principal extracellular cation and K+ is the intracellular cation. This difference in the concentration is essential for the celsurvival which is maintained by Na+-K+ pump.

Ans.73Aminopterin and amethopterin (also called as methotrexate) are structural analogues of folic acid. They competitively inhibidihydrofolate reductase and block the formation o THF. The biosynthesis of purines, thymine nucleotides and hence DNA isimpaired. This results in the blockage of cell proliferation. Aminopterin and methotrexate are successfully used in the treatment ofmany cancers, including leukemia.

Ans.74The symptoms of pellagra are commonly referred to as three Ds. The disease also progresses in that order dermatitis, diarrhoeadementia, and if not treated may rarely lead to death (4th D).

Ans.75Vitamin B12 is also known as anti pernicious anemia vitamin. It is a unique vitamin, synthesized by only microorganisms and not byanimals and plants. It was the last vitamin to be discovered. Vitamin B 12 is synthesized only by microorganisms (anaerobicbacteria). Plants cannot synthesize, hence B12 is never found in plant foods. Animals obtain B12 either by eating foods, derived fromother animals or from the intestinal bacterial synthesis.

Ans.76The enzyme commonly called hexokinase is designated ATP: D-hexose-6-phosphotransferses E.C 2.7.1.1. This identifieshexokinase as a member of class-2 (transferases), subclass 7 (transfer of a Phosphoryl group), subclass 1 (alcohol is the Phosphorylacceptor). Finally, the term hexose-6 indicates that the alcohol phosphorylated is that of carbon six of a hexose.

Ans.77

Immunoglobulins are the tumor markers for multiple myeloma.Ans.78Caries Susceptibility of different teeth:In the pioneering studies of dental caries in Hagerstown, Maryland, carried out in 1937, the rank order of susceptibility of teethcaries was listed as follows:

Mandibular first and second molars Maxillary first and second molars Mandibular second bicuspids, maxillary first and second bicuspids, maxillary central and lateral incisors Maxillary canines and mandibular first bicuspids


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Mandibular central and lateral incisors, mandibular caninesAns.79Another idea introduced the turn of the century by the well known dental histologist, J. LEON WILLIAMS, become the slogan of toral hygiene compaign of the following two decodes, A clean tooth never decays.

Ans.80CLASSIFICATION OF INDICES:I. Based upon the direction in which their scores fluctuate, indices are classified as:1. Irreversible: Index that measures conditions that will not change. For Example: DMFT index for measuring dental caries.2. Reversible: Index that measures conditions that can be changed. For example: Community Periodontal Index, Sulcular BleediIndex

II. Based upon the extent to which areas of oral cavity are measured, they are classified as:1. Full Mouth Indices: These indices measure the entire periodontium or dentition. For example: Russels periodontal Index2. Simplified Indices: These indices measure only a representative sample of dental apparatus. For example: Oral Hygiene Indsimplified.

III. Based on the certain general categories, they are classified as:1. Disease Index: The decay component of the DMFT index is the best example.2. Symptom Index: The indices measuring gingival/sulcular bleeding is the best example.3. Treatment Index: The filled component of the DMFT index is the best example.

IV. Based on the special categories as:1. Simple Index: Index that measures the presence or absence of a condition. For example: Russels periodontal index.2. Cumulative Index: Index that measures all the evidence of a condition, past and present. For example: DMF index for dental cari

Ans.81YOUNGS CLASSIFICATION OF ENAMEL FLUOROSISA classification for enamel fluorosis was developed by YOUNG, M. A., in 1973.Young classified enamel fluorosis as follows:

Classification CriteriaType A White areas less than 2 mm in diameter.Type B White areas of, or greater than, 2 mm in diameter.Type C Coloured (brown) areas of, or greater than 2 mm in diameter, irrespective of there being any white areas

Type D Coloured (brown) areas of, or greater than 2 mm in diameter, irrespective of there being white areas.Type E Horizontal white lines irrespective of there being any white non-linear areas.Type F Coloured (brown) or white areas or lines associated with pits or hypoplastic areas.

Ans.82Lactobacillus Test:Application:

Lactobacillus levels are highly influenced by the intake of dietary carbohydrates, thus reflecting the amount of bactersubstrate and indicating an acid environment within the oral cavity.

Ans.83DEWAR TEST:

Principle:

This test is similar to the Fosdick Calcium Dissolution test. The only difference is that in Dewar Test, the final pH after 4 hoursmeasured instead of the amount of calcium dissolved.This procedure is not commonly used as it has not been adequately tested for clinical correlation.

Ans.84TOOTH BRUSHING TECHNIQUES:A number of tooth brushing techniques have achieved acceptance by the Dental Profession. Each technique has been designedachieve a definite goal. Hence, no one procedure can be described as the best. Depending on the individual cases, the techniquestooth brushing may have to be altered to achieve the maximum beneficial effect. These methods are classified broadly accordingGreene J.C (1966) AS:


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The Roll technique: Modified Stillman / Rolling StrokeThe Vibratory technique: Stillman, Charters & Bass methodThe Circular technique: Fones methodThe Vertical technique: Leonards methodThe Horizontal technique: Scrub-Brush methodThe Physiological technique: Smiths method.

Ans.85In recent years, there has been a steady increase in mental disorders. Alzheimers disease described as the silent epidemic of tcentury is an important cause of morbidity and mortality.

Ans.86Evaluation of a Screening Test:

a. Sensitivity (true positive) = a/ (a + c) X 100b. Specificity (true negative) = d/ (b+ d) X 100c. Predictive value of a positive test = a/ (a + b) X 100d. Predictive value of a negative test = d/ (c + d) X 100e. Percentage of false negatives = c/ (a + c) X 100f. Percentage of false positives = b/ (b + d) X 100

Ans.91

Shrivastav committee, 1975The Government of India in the Ministry of Health and Family planning had in November 1974 set up a Group on Medical Educatiand Support Manpower popularly known as the Shrivastav Committee:

(1) To devise a suitable curriculum for training a cadre of health assistants so that they can serve as a link between the qualifimedical practitioners and the multipurpose workers, thus forming an effective team to deliver health care, family welfare anutritional services to the people

(2) To suggest steps for improving the existing medical educational processes as to provide due emphasis on the problemparticularly relevant to national requirements,

(3) To make any other suggestions to realize the above objectives and matters incidental thereto.The group submitted its report in April 1975. It recommended immediate action for :

(1) Creation of bands of para-professional and semi-professional health workers from within the community itself (e.g. schoteachers, postmasters, gram sevaks) to provide simple, promotive, preventive and curative health services needed by tcommunity;

(2) Establishment of 2 cadres of health workers, namely multipurpose health workers and health assistants between tcommunity level workers and doctors at the PHC:

(3) Development of a Referral Services Complex by establishing proper linkages between the PHC and higher level referand service centres, viz taluka/tehsil, district, regional and medical college hospitals, and

(4) Establishment of a Medical and Health Education Commission for planning and implementing the reforms needed in heaand medical education on the lines of the University Grants Commission.

The committee felt that by the end of the sixth Plan, one male and one female health worker should be available for every 5,0population. Also, there should be one male and female health assistant for 2 male and 2 female health workers respectively. T

health assistants should be located at the subcentre, and not at the PHC.

Ans.92Classification of amelogenesis imperfect according to Witkop (1989)

Type I Hypoplastic

IAIBICIDIE

Hypoplastic, pitted autosomal dominantHypoplastic, local autosomal dominantHypoplastic, pitted autosomal recessiveHypoplastic, smooth, autosomal dominantHypoplastic, smooth X-linked dominant

DiagnosisScreening test results

Diseased Not Diseased

Total

Positive a (True Positive) b (False Positive) a + bNegative c (False Negative) d (True Negative) c + d

Total a + c b + d a+ b+c+d


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IFIG

Hypoplastic, rough autosomal dominantEnamel agenesis, autosomal recessive

Type II Hypomaturation

IIAIIBIIC

Hypomaturation, pigmented autosomal recessiveHypomaturation, X-linked recessiveSnow-capped teeth, autosomal dominant

Type III Hypocalcified

IIIAIIIB

Autosomal dominantAutosomal recessive

Type IV Hypomaturation-hypoplastic with taurodontismIVAIVB

Hypomaturation-hypoplastic with taurodontism, autosomal dominantHypoplastic-hypomaturation with taurodontism, autosomal dominant

Ans.93Central giant cell granuloma is essentially a destructive lesion, producing a radiolucent area with either a relatively smooth or a raggborder, and sometimes showing faint trabeculae. Definite loculations are often present, particularly in larger lesions.

Ans.94Kaposis sarcoma has a similar histopathologic appearance in all of its clinical subtypes. The early lesion (patch stage)characterized by a proliferation of small veins and capillaries around one or more preexisting dilated vessels.More advanced lesions (plaque stage) are nodular and show increased numbers of small capillaries or dilated vascular channeinterspersed with proliferating sheets of sarcomatous or atypical spindle cells, often with large numbers of extravasated erythrocyand abundant hemosiderin deposition. In the nodular stage, all the histologic features are more prominent than plaque stage.

Ans.95Hyaline body or Rushton body, often found in great numbers in the epithelium of apical periodontal or residual cysts. These hyalbodies are tiny linear or arc-shaped bodies, generally associated with the lining epithelium, that appear amorphous in structucosinophilic in reaction and brittle in nature, since they evidence fracture in some cases. Their frequency of occurrence in cyst lininranges between 2.6 and 9.5 per cent of cysts, according to a review by Allison. The etiology, pathogenesis, and significance of thstructures are unknown.Occasionally, the lumen may contain a great deal of cholesterol, and in rare instances, limited amounts of keratin are present.

Ans.96Scrapings obtained from the base of the lesions are stained with Wrights, and Giemsa stain. Pap stain demonstrates balloon cemultinucleated giant cells and intranuclear inclusions. Though cytological procedures give a quick results but it will not differentibetween HSV and VZV more than that identification of giant cells requires experience.

Ans.98It is characterized by a rapidly acquired adiposity about the upper portion of the body, mooning of the face, a tendency to becomround-shouldered and develop a buffalo hump at the base of the neck, alteration in hair distribution, a dusky plethoric appearanwith formation of purple striae, muscular weakness, vascular hypertension, glycosuria not controlled by insulin, and albuminuria.

Ans.99The pronounced anemia is of a hypochromic microcytic type, the red cells exhibiting a poikilocytosis and anisocytosis. These ceare extremely pale, but in some instances appear as target cells with a condensation of coloring matter in the center of the cell. Tpresence of typical safety-pin cells and of nor-moblasts or nucleated red blood cells in the circulating blood is also a characterisfeature.

Ans.100

Oral lichen planus (OLP) is a common mucocutaneous disease. It was first described by Wilson in 1869 and is thought to affect 0.5per cent of the worlds population. The condition can affect either the skin or mucosa or both. It can cause bilateral white striatiopapules, or plaques on the buccal mucosa, tongue, and gingivae. Erythema, erosions, and blisters may or may not be present. Tinvolvement of the oral mucous membrane is so frequent and accompanies or precedes the appearance of lesions on the skin agenital mucous membrane.

Ans.101Papillomas of the lips have been a striking feature in a number of these patients as well as papillomas of the buccal mucosa gingival. In addition, the teeth are commonly defective in size, shape or structure. Microdontia is a common finding as is enam


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hypoplasia. Cleft lips/cleft palate has also been described in several cases. Details of the disease have been discussed by Gorlin ahis associates.

Ans.102The involved tooth is usually nonvital and may be slightly tender to percussion, and percussion may produce a dull sound instead onormal metallic sound because of the presence of granulation tissue around the root apex. Patients may complain about mild pain biting or chewing on solid food. In some cases, the tooth feels slightly elongated in its socket and may actually be so. The sensitivis due to hyperemia, edema, and inflammation of the apical periodontal ligament.

Ans.103When lesions occur on the face, they normally appear on the cheeks, eyelids, and bridge of the nose, at times producing a butterflshaped lesion that may resemble lupus erythematosus. If the eyelids are involved, they may become edematous and shut, thereresembling angioedema.

Ans.104In some instances, there may be an associated osteogenic reaction, which exhibits a sun ray radiographic pattern that can mistaken for osteosarcoma. The tumor also can occur at other locations; the skull, mandible, brain, and epididymis or testis is most frequent extramaxillary sites. There is no apparent sex predilection.High urinary levels of vanillylmandelic acid (VMA) often are found in patients with melanotic neuroectodermal tumor of infancy.

Ans.105Radiographically, the most common feature is the presence of loose bodies in the joint. These consist of rounded, irregularly shapand variably sized radiopaque structures in the region of the joint. Other features include irregularity of the joint space, widened jo

space, and irregularity of the condylar head.

Ans.106Years Concepts Persons associated with

1895 Discovery of X-rays W. C. Roentgen

Ans.107Characteristic radiation accounts for a very small part of X-rays produced in the dental X-ray machine and occurs only at 70 kVp aabove, because the binding energy of K shell electron is approximately 70 kVp.

Ans.108Type of film:

Film speed: High speed films require less mAs in order to obtain a density change. Film latitude: It is measured as a range of exposures that can be recorded as distinguishable densities on a film. Radiographic noise: It is the appearance of uneven density of a uniformly exposed radiographic film. It is seen on a small area

film as localized variations in density. The primary cause is radiographic mottle.Screens: Use of screens require less mAs in order to obtain a density change.Grids: The use of grids require more mAs in order to obtain a density change.Amount of filtration used: Reduction in the amount of added filtration used will increase the number of photons reaching the fiand hence increase the density.Fog: Film fog may result in an undesirable form of darkening of the film.

Ans.109Compositiona. Base: Made of either a stiff sheet of cardboard or polyester plastic material (like the one used for the base of the radiograp

film). It is about 0.25 mm thick. The base is the supporting component of the screen.

b. Reflecting layer: This is a thin layer of white material (i.e. magnesium oxide or titanium dioxide) between the base and luminescent layer. It serves to redirect to the film a large fraction of the emitted visible light which is moving away from the fiand which would therefore otherwise be lost. Thus, it increases the sensitivity but some degree of unsharpness is created becauof divergence of light reflected back to the film.

c. Phosphor layer: This layer consists of light sensitive phosphor crystals suspended in a plastic material.When these crystals are struck by photons they fluoresce, that is, they emit visible light photons that expose the X-ray film. Eva single X-ray photon absorbed in an intensifying screen generates many light photons leading to increased film exposure. Tspeed of the screens increases as the crystal size increases but the overall image quality may be degraded.Types of phosphor used in dental screens are:


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i. Crystalline Calcium Tungstate, that fluoresces in the blue portion of the spectrum. Conventional screens (Kodak X-OmaRegular screens) are used with blue sensitive films.

ii. Rare earth intensifying screens using terbium activated gadolinium oxysulphide and thelium activated lanthanuoxybromide, which fluoresce in the green portion of the spectrum.

The newer rare earth screens have phosphors that emit green light. The term rare earth is used because it is difficult aexpensive to separate these elements from earth and from each other and not because these elements are rare. Rare eaintensifying screens are four times more efficient than calcium screens and are considered faster, and thus less exposurerequired when these rare earth screens are used. Rare earth screens (Kodak Lanex Regular and Medium screens) are designed use with green sensitive films.

d. Coat: This layer protects the phosphor layer from mechanical insult such as abrasion, scratching, etc. it is important to keep intensifying screens clean, because any debris, spots which are opaque to visible light or scratches will result in light (undexposed) spots on the resultant radiograph.

Ans.110The basic principles of projection geometry (shadow casting) are:1. The focal spot (source of radiation) should be as small as possible2. The focal spot-object distance should e as long as possible3. The object-film distance should be as small as possible4. The long axis of the object and the film planes should be parallel5. The X-ray beam should strike the object and the film planes at right angles6. There should be no movement of the tube, film or patient during exposure. (Given by Mason and Lincoln)Ans.111Summary of Comparison between Short cone and Long cone TechniqueShort cone Long cone1. Diffusion and distortion of the image2. Increased chances of elongation of shortening of the image3. Distorted image of the teeth due to oblique exposure and

bending of the film4. Shadows of the alveolar bone tend to fill the interproximal

spaces5. More vertical angulation6. Superimposition of the shadow of the zygomatic arch on the

teeth

7. Easier technique to maneuver and requires less space8. More effective when the palate is shallow, children with

adult size teeth but underdeveloped jaws9. In rare cases when the teeth are longer than film, the entire

tooth may be seen, by over angulating the vertical angulation10. Cone cutting is a common error especially, in the maxillary

third molar area11. Curved film due to incorrect finger pressure

1. Sharp details of the image obtained2. Image obtained is of the same size and shape as the object3. Image of the teeth nearly anatomically accurate, from use

right angle exposure and flat surface of the film4. Alveolar crest seen in true relationship to the teeth5. Less vertical angulation, thus similar buccal and lingual pa

of the teeth appear closed to each other in the radiograph, amore tooth area underneath restorations is revealed.

6. Less vertical angulation in the maxillary molar region avoithe shadow of the zygomatic arch and the teeth apices a

maxillary sinus are better seen7. Needs a larger working space8. In a similar situation apices of the teeth may be cut off9. This is not possible in the long cone technique10. The PID, helps reduce such errors11. Use of film holding device prevents such an error.

Ans.112Typical radiographic description of various oral lesions as seen on the radiograph

Egg shell appearance Ameloblastoma

Multilocular cyst

Ans.113Immunohistochemistry, gel electrophoresis, and immunoblot techniques have made identification of the characteristic pattern cytokeratins possible in each epithelial type. The keratin proteins are composed of different polypeptide subunits characterized their isoelectric points and molecular weights. They are numbered in a sequence contrary to their molecular weight.


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Ans.114Within 2 weeks, a nearly mature microbiota is established in the gut of the newborn. After weaning (>2 years), the entire hummicrobial flora is formed by a complex collection of approximately 10 microorganisms consisting of more than 400 different types bacteria.

Ans.115The transition from gram-positive to gram-negative microorganisms observed in the structural development of dental plaqueparalleled by a physiologic transition in the developing plaque.

Ans.116Many periodontal pathogens stimulate the production of interleukin-8 (IL-8), a proinflammatory chemokine that provides a signal fthe recruitment of neutrophils (PMNs) to local site (see later discussion). P. gingivalis is able to inhibit the production of IL-8 epithelial cells, which may provide the microorganism with an advantage in evading PMN-mediated killing.

Ans.117The initial biologic processes and bone remodeling needed to complete the first remodeling cycle of bone around an implant requan estimated 4 months in humans.

Ans.118Neutropenia is a blood disorder that results in low levels of circulating neutrophils. An individual with an absolute neutrophil cou(ANC) of less than 1500 cells per microliter is considered to beneutropenic.

Ans.119

Prominent periodontal pathogen such as P. gingivalis, T. forsythia, F. nucleatum, P. micros, E. corrodens, and Streptococcintermedius have been found to be elevated in patients who do not respond to treatment.

Ans.120The chronic gingivitis, which occurs 2 to 3 weeks after the beginning of plaque accumulation, the blood vessels become engorged acongested, venous return is impaired, and the blood flow becomes sluggish.

Ans.121Wasting Disease of the TeethWasting is defined as any gradual loss of tooth, substance characterized by the formation of smooth, polished surfaces, without regato the possible mechanism of this loss. The forms of wasting are erosion, abrasion, attrition, and abfraction.

Ans.122

Exostoses are outgrowths of bone of varied size and shape. Palatal exostoses have been found in 40% of human skulls.

Ans.123Phases of Periodontal Therapy

Surgical phase (Phase II Therapy)Periodontal therapy, including placement of implantsEndodontic therapy

Ans.124The maintenance phase of periodontal treatment starts immediately after the completion of Phase I therapy.

Ans.125Internal bevel incision is the initial incision in the reflection of periodontal flap. It is also known as reverse bevel incision.

Ans.126It can lead to bone necrosis if electrode touches the bone, can also cause cementum burns.

Ans.127Lymphatic Drainage of the FaceThe face has three lymphatic territories:

(a) The upper territory, including the greater part of the forehead, the lateral halves of the eyelids, the conjunctiva, the lateral pof the cheek and the parotid area, drains into the preauricular parotid nodes.


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(b) The middle territory, including a strip over the median part of the forehead, the external nose, the upper lip, the lateral partthe lower lip, the medial halves of the eyelids, the medial part of the cheek, and the greater part of the lower jaw, drains inthe submandibular nodes.

(c) The lower territory, including the central part of the lower lip and the chin, drains into the submental nodes.Ans.128The temporal branches cross the zygomatic arch and supply:

(a) The auricularis anterior.(b) The auricularis superior.(c) The intrinsic muscles on the lateral side of the ear.(d) The frontalis.(e) The orbicularis oculi.(f) The corrugator supercilii.

Ans.129Branches of First Part of the Maxillary Artery1. The deep auricular artery supplies the external acoustic meatus, the tympanic membrane and the temporomandibular joint.2. The anterior tympanic branch supplies the middle ear including the medial surface of the tympanic membrane.3. The accessory meningeal artery enters the cranial cavity through the foramen ovale. Apart from the meninges it suppl

structures in the infratemporal fossa.4. The inferior alveolar artery runs downwards and forwards medial to the ramus of the mandible to reach the mandibular forame

Passing through this foramen the artery enters the mandibular canal (within the body of the mandible) in which it runs downwarand then forwards.

Before entering the mandibular canal the artery gives off a lingual branch to the tongue; and a mylohyoid branch that descendsthe mylohyoid groove (on the medial aspect of the mandible) and runs forwards above the mylohyoid muscle.Within the mandibular canal the artery gives branches to the mandible and to the roots of the each tooth attached to the bone.also gives off a mental branch that passes through the mental foramen to supply the chin.

Ans.130Submandibular GanglionThis is a parasympathetic peripheral ganglion. It is a relay station for secretomotor fibres to the submandibular and sublingsalivary glands. Topographically, it is related to the lingual nerve, but functionally, it is connected to the chorda tympani branch of facial nerve.The fusiform ganglion lies on the hyoglossus muscle just above the deep part of the submandibular salivary gland, suspended from tlingual nerve by two roots.Conenctios and Branches

1. The motor or parasympathetic fibres pass from the lingual nerve to the ganglion through the posterior root. These preganglionic fibres that arise in the superior salovatory nucleus and pass through the facial nerve, the chorda tympani athe lingual nerve to reach the ganglion.The fibres relay in the ganglion: Postganglionic fibres for the submandibular gland reach the gland through five or branches from the ganglion.Postganglionic fibres for the sublingual and anterior lingual glands re-enter the lingual nerve through the anterior root atravel to the gland thought the distal part of the lingual nerve.

2. The sympathetic fibres are derived from the plexus aroud the facial artery. It contains postganglionic fibres arising in superior cervical ganglion. They pass through submandibular ganglion without relay, and supply vasomotor fibres to submandibular and sublingual glands.

3. Sensory fibres reach ganglion through the lingual nerve.Ans.131

The root portion of the tooth is firmly fixed in the bony process of the jaw, so that each tooth is held in its position relative to tothers in the dental arch. That portion of the jaw serving as support for the tooth is called the alveolar process. The bone of the tosocket is called the albeolus (plural, alveoli).The crown portion is never covered by bone tissue after fully erupted, but it is partly covered at the cervical third in young adults soft tissue of the mouth known as the gingiva or gingival tissue, or gums. In some persons, all of the enamel and often some cervicementum may not be covered by the gingiva.

Ans.132Masseter MuscleThe masseter muscle extends from the zygomatic arch to the ramus and body of the mandible. The insertion of this muscle is broextending from the region of the second molar on the lateral surface of the mandible to the posterior lateral surface of the ramus. T


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masseter muscle is covered partly by the platysma muscle and by the risorius muscle. The platysma is activated during firm clenchiin some individuals and, having some insertion in the orbicular muscle (orbicularis oris), is sometimes active in facial expression. Trisorius is affected by emotion and is active in facial expression.The superficial part of the masseter muscle is separated distinctly only from the deeper layer of the muscle at the posterior upper pof the muscle. The masseter muscle is covered partly and to a variable degree with the parotid gland tissue. The center of the lowthird of the masseter muscle is about 2 to 3 cm from the anterior border of the sternocleidomastoid muscle, which contracts duriclenching in some individuals. The masseter muscle is active during forceful jaw closing and may assist in protrusion of mandible. The masseter muscle is innervated by the fifth nerve (masseter nerve). The zygomaticomandibular muscle (deep massemuscle) inserts at the coronoid process and originates on the inner surface of the zygomatic arch. It may be an antagonist to posterior temporalis and a synergist for the lateral pterygoid muscle.

Ans.133FibersThe collagen fibers in the pulp exhibit typical cross striations at 64 nm (640 ) and range in length from 10 to 100 nm or more. Tmain type of collagen fiber in the pulp is type I. Type III collagen is also present. Bundles of these fibers appear throughout the puIn very young pulp fine fibers ranging in diameter from 10 to 12 nm (100 to 120 ) have been observed. These fine fibers are calfibrillin. Their significance is unknown. Pulp collagen fibers do not contribute to dentin matrix production, which is the functionthe odontoblast. After root completion the pulp matures and bundles of collagen fibers increase in number. They may appscattered throughout the coronal or radicular pulp, or they may appear in bundles. These are termed diffuse or bundle collagdepending on their appearance, and their presence may relate to environmental trauma. Fiber bundles are most prevalent in the rocanals, especially near the apical region.

Ans.134 Bacterial Culture and Antibiotic Sensitivity testsCultures can be obtained from the throat, spuntum, draining pus, urine or stools. Cultures from the oral cavity can be obtained eithby gathering exudative material or by aspiration with a needle and syringe or by use of a swab. A throat or pus culture is obtained collecting the sample on an autoclaved swab stick. A transport medium must be used when the sample cannot be inoculaimmediately onto a primary culture medium. For smear and culture in suspected cases of tuberculosis, the sample is sent normal saline.

FNACFine Needle Aspiration Cytology uses a fine needle (23-26G) to aspirate the contents of the lesion. A smear is prepared, stained astudied. This test may not be significant at times.

Ans.135Two Ways of Bone Removala. High speed, high toque handpiece and but techniqueb. Chisel and mallet technique.Bur technique round bur or a straight no. 703 fissure bur is used. Either of these burs can be used for bone removal or for sectioniof a tooth. Burs should be always used along with copious saline irrigation to avoid thermal trauma to the bone.

Ans.136A deep level of G.A. is enhanced by increasing alveolar concentration of L.A.Minimum alveolar concentration (MAC) of an anesthetic agent is to produce lack of reflex response to skin incision in 50% patients. Volatile anesthetic agents are rapidly removed from the body via lungs and little evidence of metabolism can demonstrated following short exposure.

Ans.137Ketamine is a phencyclidine derivative. It is a nonbarbiturate hypnotic, which produces dissociative type of anaesthesia. It produsedation, amnesia and intense analgesia. It has a very high margin of safety. It has good tissue compatibility (no irritation of vein

Since the intraoral muscles, particularly, those of the tongue, do not become relaxed under the effect of ketamine, the airway remaiunobstructed. This unique characteristic is ideal for dentistry. The addition of sedative premedication increases the incidence aspiration especially, when ketamine is used in anaesthetic doses (1-2 mg/kg IV or 8 to 10 mg/kg IM).

Ans.138Apnoea may be due to the following:a. Respiratory obstruction.b. Breath holding in light anaesthesia.c. Deep anaesthesia.d. Severe hypoxia.


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e. Grave cardiovascular depression requiring resuscitation.f. Fainting-fear, anxiety and occasionally pain in the patients presenting for outpatient dental anaesthesia, can cause significa

autonomic nervous system overactivity.

Ans.139The hypertonic saline or sclerosing solution is used for TMJ subluxation is paracapsular.

Ans.140- Bilateral submandibular incisions and if required a midline submental incision 1 cm below the inferior border of mandible a

sufficient to drain the involved spaces.- Following aseptic technique and adequate local anaesthesia, an incision is made, which divides skin, the superficial fasc

platysma, investing layer of deep fascia, geniohyoid and finally mylohyoid muscles.- To be effective, it is essential to divide deep fascia and the mylohyoid muscle, then only it will drain sublingual space. A throu

and through drain is placed to relieve the intense pressure of the oedematous tissues on the airway. Sublingual space can separately drained by intraoral approach if required and if oral opening permits it. Surgical drain should be secured by suturingthe margins of the incision.

Ans.141Whenever antral puncture is to be carried out; the puncture into the sinus cavity should be made through the middle meatus children; and in the inferior meatus in adults. The antral puncture or intranasal antrostomy, in the inferior meatus then becomes a poof dependent drainage for maxillary sinus. The floor of maxillary sinus is about 1.25 cm below the floor of the nose.

Ans.142Submandibular incision is use to access the mandibular ramus, angle and posterior body. Patient is prepared and draped in routsurgical manner. Important landmarks-the corner of the mouth and the eyeglobe must be visible. Head of the patient is turnsideways. The incision is marked 2 cm below the inferior border of the mandible to avoid damage to the marginal mandibular branof the facial nerve. Ideally the incision is placed in a relaxed skin tension line (the Langers lines)

Ans.143Advantages of Rigid Fixation:i. Rigid or stable fixation.ii. Obviates the need for immobilization of the mandible.iii. Early return to home and work.iv. Soft diet can be taken.v. Maintenance of oral hygiene.vi. Useful in mentally challenged, physically handicapped patients.

vii. Maintenance of airway in multiple fractures.The types of Rigid Fixation includes-a. Simple noncompression bone platesb. Mini bone platesc. Compression platesd. Reconstruction platesWhereas, Transosseous Wiring (Intraosseous Wiring) is a direct wiring across the fracture line is an age old and effective method fixation of jaw bone fractures.Transosseous wiring can be done through intraoral or extraoral approach. In principle, holes are drilled in the bony fragments either side of the fracture line, after which a length of 26 gauge stainless steel wire is passed through the holes and across the fractuAfter this initial preparation, the fracture must be reduced independently with the teeth in occlusion before the free ends of the wiare lightened and twisted. The twisted ends are cut short and tucked into the nearest drill hole. The single strand wire fixation in thorizontal manner is the simplest form of fixation with intraosseous wiring. But this can be modified in various ways depending

the need.Ans.144Caldwells Technique

Entire lingual mucoperiosteal flap is reflected from molar to molar region. Mylohyoid ridge is reduced / removed along with the reduction of genial tubercle. Mylohyoid muscle and superficial fibres of genioglossus muscles are pushed inferiorly. Rubber tubing placed in the lingual vestibule and the flap is held in position at the vestibular depth, by sutures passed through t

skin extraorally, at the inferior border of the mandible.


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Ans.145The cyst itself is frequently symptomless and may be discovered, when periapical radiographs are taken of teeth with nonvital pulpSlowly enlarging swellings are often complained of. Radicular cysts at times attain a large size. Pain may be a significant chcomplaint, in the presence of suppuration. Initially, the enlargement is bony hard, as the cyst increases in size; the covering bobecomes thin and exhibits springiness due to fluctuation. In the maxilla, buccal and palatal or only palatal expansion due to the lateincisor or a palatal root will be noted. In the mandible, lingual expansion is very rare. The mucosa overlying the cysts expansion,with the other cysts, is at first of normal colour, then it may become conspicuous because then it may become conspicuous because the presence of dilated blood vessels and finally it will take on a profound dark bluish tingue, in case of large cysts. An intraoral sintract may be identified with discharging pus or brownish fluid, when the cyst is infected. The involved tooth / teeth will be foundbe nonvital, discoloured, fractured or with heavy restorations or a failed root canal. They may be sensitive to percussion hypermobile, or displaced. It may involve deciduous or the permanent dentition. Temporary paraesthesia or anaesthesia of regional nerve distribution may be evident as with other cysts when infection is present. Pathologic fracture may be the formpresentation in the mandible, as with other large cysts.

Ans.146Whenever premolar extractions are carried out for relieving the crowding, the total extraction space should not be utilized. At le3 to 4 mm space should be left for making the segmental osteotomy cuts, without jeopardizing the periodontal status of the adjaceteeth. Judicious inter-proximal stripping can be carried out wherever possible, so that the entire premolar space can be utilized for back of the anterior segment.Periapical X-rays of the planned osteotomy region should be taken and if roots are convergent, they are made divergent. The eqamount of space should be created between the crowns as well as roots of the teeth adjacent to the osteotomy sites.

Ans.147

Mandibular nerve is the nerve of first (mandibular) branchial arch. The first ach gibes rise to the following: Precursor of mandible (Meckels cartilage) Spine of sphenoid Sphenomandibular ligament Muscles of mastication.

It is the largest branch of trigeminal nerve.It transmits sensory fibres from the skin over the mandible, side of the cheek and temple, the oral cavity and its contenexternal ear, tympanic membrane and TM joint. It also supplies the meninges of cranial vault.It is motor supply to the muscles derived from first branchial arch: Temporalis and masseter Medial and lateral pterygoid Mylohyoid and anterior belly of digastrics Tensor tympani and tensor palati.- Note the four groups of two-two tensors, two pterygoids, and two big chewing muscles and two in floor of mouth.- Some of its distal branches also convey parasympathic secretomotor fibres to salivary glands and taste fibers fro

anterior portion of tongue.

Ans.148 Class Iarches are most common and class IV is least common. Class I and class II, long span class III and IV partial dentures are tooth-tissue supported prostheses. Short span class III and IV are tooth supported partial dentures.Ans.149 The retentive undercut will be present only in relation to a given path of insertion. The retentive undercut is absent in conditio

where the direction of dislodgement of the clasp arm is similar to the direction along which the clasp arm was inserted. Henceis important to maintain a single path of insertion that does not coincide with the path of displacement.

Path of displacement is any path of movement of the clasp without resistance. Hence, there will be no height of contoobstructing the movement of the retentive arm along any path of displacement. It the path of insertion and displacement of tdenture are parallel to one another it simply means that there is no retentive undercut present along the path of insertion.

Ans.150After tripoding the primary cast, three additional reference points are marked on the cast using the same procedure described to mathe first three tripod marks. The commonly used additional reference points are: Distal marginal ridge of the first premolar. Incisal edge of lateral incisor. Lingual cusp tip of the first premolar on the opposite side (opposite to the side where the other two points were marked.


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Ans.151 Surgical Splints are used to protect post-operative surgical sites in the oral cavity to improve the healing. They are m

commonly used on the maxillary arch and the lingual side of mandibular ridge where tori and exostoses are most likely to occur Clinical procedure Impression is made with irreversible hydrocolloid.Ans.152The Buccal Frenum separates the labial and buccal vestibule. It has attachments of the following muscles,Levator anguli oris - Attaches beneath the frenum

Orbicularis oris - Pulls the fernum in a forward directionBuccinators - Pulls the frenum in the backward direction.These muscles influence the position of the buccal frenum hence it needs greater (wider and relatively shallower) clearance on tbuccal flange of the denture.

Ans.153Anthropometric cephalic index - The transverse circumference of the head is measured using a measuring tape at the level of tforehead. The width of the upper central incisor can be derived from this measurement. Sears called this formula as anthropometric cephalic index.

Width of the upper central incisor = Circumference of the head13

Ans.154Lingualized Occlusion was first proposed by Alfred Gysi in 1927. This type of occlusion involves the use of a large upper palacusp against a wide lower central fossa. In this scheme, the buccal cusps of the upper and lower teeth do not contact each othClough reported that 67% of the patients preferred lingualized occlusion due to its superior chewing efficiency.

Ans.155Advantages and Disadvantages of Different Margin Designs

Advantages Disadvantages Indications

Sloppedshoulder

Bulk of material, advantages ofbevel

Less conservative of tooth structure Facial margins of metal-ceramic crowns

Ans.156 If the distance between the finish line and the alveolar crest (combined width of epithelial and connective tissue attachments)

less than 2.0 mm, the restoration may lead to gingival inflammation, loss of alveolar crest and pocket formation. A cro

lengthening procedure should be done to move the alveolar crest to a location about 3.0 mm away from the finish line to preserthe periodontal health.

The finish line should be at least 3 mm away from the alveolar crest to preserve the periodontium.Ans.157Full Veneer Crowns These retainers cover all the five surfaces of the abutment. They are fabricated like a cap and are usuaindicated for extensively damaged teeth. They are most retentive and ideal retainers because their design can resist masticatory forin all directions.

Ans.158Replacement of a Single Missing Canine In cases of a single missing canine, where a cantilever FPD is planned, support shouldtaken from both central and lateral incisor.

Ans.159Features Their functions

Chamfer finish line: Marginal integrity and Periodontal preservationAns.160The major Advantages of Fixed Fixed Partial Dentures include:

Easy to fabricate Economical design Strong Easy to maintain


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Robust design provides maximum retention and strength Helps to splint mobile abutments Can be used for long bridges along with periodontally weak abutments.Disadvantages

Since the connectors are rigid, unwanted stress and lever forces are directly transferred to the abutment producing considerabdamage.

Requires excessive tooth preparation to achieve a single path of placement. Difficult to cement on multiple abutments Contraindicated for pier abutments. A fixed partial denture constructed over these abutments will produce rotational forces around the pier (2) abutment.Ans.161Depending on the Materials Used, the implants can be classified into Metallic implants (Titanium, Titanium alloy, Cobalt ChromiuMolybdenum alloy) and Non-metalic implants (Ceramics, Carbon).

Ans.162Contact angle of Porcelien is less, hence better wetting.

Ans.163If the concentration of tin is less than 26%, the beta () phase, which is a solid solution of sliver and tin, forms. In one product, 5% is replaced by 5 % indium, whereas another product contains less than 1% palladium. Adding this small amount of palladiuenhances the mechanical properties and corrosion resistance. The replacement of silver by an equal amount of copper produce

copper tin compound(Cu3Sn).Ans.164A resin composite is composed of four major components: organic polymer matrix, inorganic filler particles, coupling agent and theinitiator accelerator system. The organic polymer matrix in most commercial composites today is either an aromatic or urethanediacrylate oligomer. Oligomers are viscous liquids, the viscosity of which is reduced to a useful clinical level by the addition of adiluents monomer.

Ans.165Most modern bonding agents bond best to a moist tooth. If dentin is overdried, it is best to rehydrate it by applying a moist cottpellet for 15 seconds before applying the primer of the bonding agent.

Ans.166Odontoblastic processes sometimes cross DEJ into enamel. When their ends are thickened, they may serve as pain receptors. These acalled enamel spindles.

Ans.167The deepest zone is known as the dark zone because it does not transmit polarized light. This light blockage is caused by the presenof many tiny pores too small to absorb quinoline. These smaller air-filled or vapor-filled pores make the region opaque. The topore volume is 2% to 4 % . There is some speculation that the dark zone is not really a stage in the sequence of the breakdownenamel; rather, the dark zone may be formed by deposition of ions into an area previously containing only large pores. Caries is episodic disease with alternating phases of demineralization and remineralization.

Ans.168Linear Coefficients of Thermal Expansion

Biomaterials/ structures LCTE (ppm/0C)

Aluminous dental porcelain 4

Alumina 6.5-8

In-Ceram 8-10

Cp-litanium 8-9


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Traditional dental cements 8-10

Tooth structure 9-11

Stainless steel 11

PFM ceramics 14

PRM alloys 14

Gold foil 14-15

Gold casting alloys 16-18

Co-cr alloys 18-20

Hybrid glass-ionomers 20-25

Dental amalgam 25

Packable composites 28-35

Anterior and flowable composites 35-50

Composite cements 40

PMMA direct-filling resins 72-83

Dental wax 260-600

Ans.169It can be differentiated from primary dentin by the sharp bending of the tubules producing a line of demarcation.

Ans.170

Chronic Periradicular diseases with areas of rarefactionChronic alveolar abscessGranulomaCyst

Chronic Periradicular disease with area of condensationCondensing osteitis

Ans.171K File (Kerr manufacturing company)- Has got the name from its manufacturing company.- Manufactured from stainless steel square blank.Ans.172

Sotokawas classification of instrument damage is:1. Type I : Bent instrument2. Type II : Stretching or straightening of twist contour.3. Type III : Peeling-off metal at blade edges.4. Type IV : Partial clockwise twist.5. Type V : Cracking along axis.6. Type VI : Full fracture

Ans.173Local Contraindications-


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1. Root Fractures : Vertical fractures have a poor prognosis.2. Destruction of the periapical tissues involving more than 1/3rd of the length of the root.3. Obstructed root canal of a pulpless tooth with a radiolucent area, i.e. curved root a tortuous canal, secondary dentin, a pulpsto

that cannot be removed or by passed, a calcified or partially calcified canal a malformed to

AIPGEE 1 Explanation

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