Dentosphere : World of Dentistry

 # Orthodontic tooth movement is affected by: A. Aspirin B. Tetracycline C. Metronidazole D. Fluoride The correct answer is A. Aspirin. • Prostaglandin E plays an essential role in the cascade of signals that leads to tooth movement, so the inhibitors of its activity affect tooth movement. Drugs that affect prostaglandin activity fall into two categories: - corticosteroids and nonsteroidal anti-inflammatory drugs (NSAIDs) that interfere with prostaglandin synthesis and - other agents that have mixed agonistic and antagonistic effects on various prostaglandins.  • In the body, prostaglandins are formed from arachidonic acid, which in turn is derived from phospholipids. Corticosteroids reduce prostaglandin synthesis by inhibiting the formation of arachidonic acid; NSAIDs inhibit the conversion of arachidonic acid to prostaglandins.  • Most NSAIDs (aspirin, ibuprofen, Naprosyn, and many others) are prostaglandin inhibitors. The major exception is acetaminophen (Tylenol), whi...

 # Shovel shaped incisor is found in: A. Down’s syndrome B. Crouzon’s syndrome C. Pierre Robin syndrome D. Gardner’s syndrome The correct answer is B. Crouzon's syndrome.  Crouzon's syndrome is a rare genetic disorder that affects the growth and development of the bones in the skull and face. People with Crouzon's syndrome typically have a distinctive appearance, including bulging eyes, a beaked nose, and a small upper jaw. Shovel-shaped incisors are a common dental anomaly seen in individuals with this syndrome, along with other dental abnormalities.

 # A 5 year old child presents with chronic bed wetting and bilateral loose first molars. His mother says that he wants to drink water several times during night. Which of the following is the most likely diagnosis? A. Hand Schuller Christian disease B. Marble bone disease C. Nieman Pick disease D. Polyostotic fibrous dysplasia The correct answer is A. Hand Schuller Christian disease.  Based on the given symptoms, the most likely diagnosis is option A, Hand Schuller Christian disease. Hand-Schuller-Christian disease (HSC) is a rare type of Langerhans cell histiocytosis, which is characterized by the infiltration and proliferation of Langerhans cells in various tissues of the body. It usually affects children under the age of 5. The chronic bedwetting and bilateral loose first molars in the child are indicative of bone involvement, which is a common feature of HSC. Additionally, the child's frequent need to drink water during the night may be due to the involvement of the pitui...

# The position of the upper occlusal rim in the articulator is adjusted by : (A) arbitrary means  (B) using face-bow  (C) visual examination  (D) adjusting the incisal pin  The correct answer is B. Using face bow. The position of the upper occlusal rim in the articulator is adjusted by using a face-bow. A face-bow is a dental instrument that is used to transfer the position of the patient's maxillary arch to the articulator. The face-bow records the position of the maxilla in relation to the patient's hinge axis and transfers it to the articulator. This ensures that the upper model is mounted in the same position in the articulator as it is in the patient's mouth, allowing for accurate and precise restorations. (A) Arbitrary means, (C) visual examination, and (D) adjusting the incisal pin are not accurate methods for adjusting the position of the upper occlusal rim in the articulator.

# Kennedy classification is determined by: (A) the most anterior tooth missing  (B) the first tooth to be lost   (C) the largest tooth in the space  (D) the most posterior tooth missing  The correct answer is D. the most posterior tooth missing.  Kennedy classification is determined by the most posterior tooth missing on both sides of the arch. Therefore, the correct option is (D) the most posterior tooth missing. The Kennedy classification system is used to classify partially edentulous arches (i.e., arches with missing teeth) for the purpose of designing removable partial dentures. The classification is based on the location and extent of the edentulous spaces, and it takes into account the position of the remaining natural teeth and their strategic importance in supporting the prosthesis. The classification has four main categories (Class I, II, III, and IV), each of which is further divided into subcategories based on the specific edentulous spaces pres...

# The objective of full mouth rehabilitation is: (A) to treat periodontal conditions  (B) to minimize undue destructive stress to the tissues  (C) to replace lost teeth  (D) to bring in proper occlusion  The correct answer is D. To bring in proper occlusion. The objective of full mouth rehabilitation is to bring in proper occlusion, which means achieving a balanced and stable relationship between the upper and lower teeth and the temporomandibular joints (TMJs). Therefore, the correct option is (D) to bring in proper occlusion. While treating periodontal conditions, minimizing undue destructive stress to the tissues, and replacing lost teeth may be important components of a full mouth rehabilitation plan, the ultimate goal is to achieve proper occlusion.

 # Which of the cells most commonly found in granuloma?  (A) Lymphocytes  (B) Giant cells  (C) Mast cells  (D) Neutrophils The correct answer is B. Giant cells. The cell most commonly found in granuloma is giant cells. A granuloma is a type of inflammation that occurs in response to chronic infection or inflammation. It is characterized by the accumulation of immune cells such as macrophages, lymphocytes, and giant cells, which are often surrounded by a rim of fibrous tissue. Giant cells are formed by the fusion of macrophages and are a characteristic feature of granulomas. They are often multinucleated and can be identified by their large size and distinctive appearance under the microscope. Lymphocytes are also commonly found in granulomas, but giant cells are the most characteristic cell type. Mast cells and neutrophils are less commonly found in granulomas.

  # The carotid body is a: (A) pressure receptor  (B) pH receptor  (C) osmo receptor  (D) chemo receptor The correct answer is D. Chemo receptor.  The carotid body is a chemoreceptor. It is a small cluster of specialized cells located near the bifurcation of the common carotid artery in the neck. The carotid body senses changes in the levels of oxygen, carbon dioxide, and pH in the blood and sends this information to the brainstem, where it is used to regulate breathing rate and other physiological responses. The carotid body is an important component of the body's homeostatic control mechanisms, helping to ensure that oxygen levels in the blood are maintained within a narrow range.

 # The suture that maintains strength for longest time is:  (A) Dexon  (B) Vicryl  (C) PDS  (D) Chromic catgut  The correct answer is C. PDS.  The suture that maintains strength for the longest time is PDS (Polydioxanone). PDS is a synthetic absorbable suture that is gradually broken down by hydrolysis and is intended to be absorbed by the body over a period of approximately 6 months. In comparison, Vicryl (Polyglactin 910) and Dexon (Polyglycolic acid) are also absorbable sutures, but they typically maintain their strength for a period of 4 to 6 weeks and 4 to 6 months, respectively. Chromic catgut is a natural absorbable suture that is made from purified collagen fibers derived from the serosal layer of sheep intestines. Its strength retention is about 14 to 21 days.

 # Which among the following is elevated in hemophilia A?  (A) PT  (B) CT  (C) APTT  (D) PT and APTT  The correct answer is C. APTT. PT (prothrombin time) is typically normal in hemophilia A. Hemophilia A is a genetic disorder that affects the coagulation system, specifically the clotting factor VIII. PT measures the extrinsic pathway of coagulation, which is not affected in hemophilia A. Instead, hemophilia A patients typically have a prolonged activated partial thromboplastin time (aPTT), which measures the intrinsic pathway of coagulation. 

# Radioisotopes are used in the following techniques, except: (A) Mass spectroscopy  (B) RIA (C) ELISA  (D) Sequencing of nucleic acid The correct answer is C. ELISA. Radioisotopes were commonly used in ELISA (Enzyme-Linked Immunosorbent Assay) in the past, but they are no longer commonly used due to safety concerns and advances in technology. In the past, radioactive isotopes such as iodine-125 and tritium were used to label antibodies or antigens in ELISA. These isotopes emit radiation that can be detected and measured to quantify the amount of labeled molecule in a sample. However, the use of radioisotopes poses risks to laboratory personnel and the environment due to the potential for radiation exposure. Today, non-radioactive labeling methods such as fluorescent dyes or enzymes are more commonly used in ELISA. These methods are safer and more convenient, and they can provide similar sensitivity and specificity as radioisotope-based assays.

 1. Most accepted theory for the conduction of pain is: (A) gate control theory  (B) specificity theory  (C) membrane stabilization theory  (D) none of the above  2. For a patient suffering from cirrhosis of liver, the safest group of LA is:  (A) general anesthesia  (B) ester group  (C) conscious sedation  (D) amide group 3. The site of action of the local anesthetic agent is on: (A) perinum  (B) axonium  (C) nerve membrane (D) epineurium  4. Which is the most potent topical anesthetic?  (A) Benzocaine  (B) Tetracaine  (C) Mepivacaine  (D) Prilocaine  5. Local anesthetic agent is absolutely contraindicated in:  (A) hyperthyroidism  (B) bronchial asthma  (C) diabetes mellitus  (D) hypertension  6. The deficiency of which of the following does not affect on tooth development?  (A) Vitamin A  (B) Vitamin D  (C) Vitamin C  (D) Vitamin K  7. Pindborg tumour a...

 Full Marks: 100                    Time : 3 hours Subject - Dentistry  SECTION A                20 Marks 1.  How does hemophilia impact dental treatment and what precautions should be taken by dental surgeon to ensure the safety of patients with hemophilia? Discuss.   4+6=10 2. Classify fibro-osseous lesions. Discuss in detail about Paget's disease of bone.    10 SECTION B      30 Marks 3. A patient comes with the swelling of the left side of face due to carious lower first molar; which space is involved by the infection? Write about the boundaries and treatment of the buccal space infection. Also state on Gow Gates technique.      2+5+3=10 4. Describe briefly various intraoral radiographic techniques. But among them, write in detail about bite wing radiography.      5+5=10 5. Explain in detail on nonvital bleaching wi...

 # A young patient has white thickening of buccal mucosa since birth and it also occurs in nose and esophagus. Most likely diagnosis is:  a. accumulation of fordyces granules  b. chronic hyperplastic candidiasis  c. white sponge nevus  d. porokeratosis  The correct answer is C. White sponge nevus.  This mucosal abnormality is congenital in many instances. In other cases, it does not appear until infancy, childhood, or even adolescence, by which time it has generally reached the full extent of its severity. The oral lesions may be widespread, often involving the cheeks, palate, gingiva, floor of the mouth, and portions of the tongue. The mucosa appears thickened and folded or corrugated with a soft or spongy texture and a peculiar white opalescent hue. There is sometimes a minimal amount of folding present. Ragged white areas may also be present which can be removed sometimes by gentle rubbing without any ensuing bleeding. 

 # Organ involvement of SLE is in: a. kidney and Lungs  b. kidney and heart  c. lungs and heart  d. heart and spleen  The correct answer is B. Kidney and heart. Systemic lupus erythematosus is a serious cutaneous-systemic disorder which characteristically manifests repeated remissions and exacerbations. This disease has its peak age of onset at about 30 years in females but about 40 years in males. The disease may occur in childhood as reported by Jacobs. Prevalence rates are higher in females than in males. A female-to-male ratio of approximately 2 : 1 occurs before puberty, and a ratio of 4 : 1 occurs after puberty. The generalized manifestations of the systemic disease are referable to the involvement of various organs, including the kidney and heart. In the kidney, fibrinoid thickening of glomerular capillaries occurs, producing the characteristic ‘wire loops,’ which may be sufficient to result in renal insufficiency. The heart may suffer from an atypical en...

 # Prodromal symptom of OSMF: a. hypersalivation  b. dryness of mouth  c. both of the above  d. none of the above  The correct answer is C. Both of the above. Prodromal Symptoms (Early OSF):  This includes a burning sensation in the mouth when consuming spicy food, appearance of blisters especially on the palate, ulcerations or recurrent generalized inflammation of the oral mucosa, excessive salivation, defective gustatory sensation and dryness of the mouth. There are periods of exacerbation manifested by the appearance of small vesicles in the cheek and palate. The intervals between such exacerbation vary from three months to one year. Focal vascular dilatations manifest clinically as petechiae in the early stages of the disease. This may be part of a vascular response due to hypersensitivity of the oral mucosa towards some external irritant like arecanut products. Petechiae are observed in about 22% of OSF cases (Rajendran, 1994), mostly on the tongue fol...

# Pathergy test is done in:  a. bechet syndrome  b. senear usher syndrome  c. weber cockayna syndrome  d. epidermolysis bullosa  The correct answer is: A. Bechet syndrome. Pathergy phenomenon has been well known to dermatologists since it was first described in 1937 by Blobner as a state of altered tissue reactivity in response to minor trauma. The pathergy test is a nonspecific hypersensitivity skin reaction induced by needle prick that is performed to look for evidence of this phenomenon. Pathergy lesions are generally manifested clinically by erythematous induration at the location of skin trauma, which may remain as papules or progress to sterile pustules. Although the precise mechanism of pathergy has not yet been entirely elucidated, the skin injury by needle prick in patients exhibiting pathergy is thought to trigger a cutaneous inflammatory response that is exaggerated and more prominent than that seen in normal skin. An increased release of cytokines fr...

 # Which of the following is not a characteristic of Paterson-brown-kelly syndrome?  a. koilonychia  b. dysphagia  c. iron deficiency anemia  d. none of the above  The correct answer is D. None of the above. Iron Deficiency Anemia and Plummer-Vinson Syndrome (Paterson-Brown-Kelly syndrome, Paterson-Kelly syndrome, sideropenic dysphagia) Iron deficiency is an exceedingly prevalent form of anemia, particularly in females. Iron deficiency is the most prevalent single deficiency state on a worldwide basis. It has been estimated that between 5 and 30% of women in the United States are iron deficient, while in some parts of the world, this may reach 50% . Men are only rarely affected.  While an iron-deficiency anemia may occur at any age, the Plummer-Vinson syndrome occurs chiefly in women in the fourth and fifth decades of life. Presenting symptoms of the anemia and the syndrome are cracks or fissures at the corners of the mouth (angular cheilitis), a lemon...

 # Osteogenesis imperfecta:  a. Is a sex linked disorder of bones that develop in cartilage b. Manifests with blue sclera which are pathognomonic of this disease  c. May be associated with deafness  d. Has associations with amelogenesis imperfecta The correct answer is B. Manifests with blue sclera which are pathognomonic of this disease. A second characteristic clinical feature of osteogenesis imperfecta is the occurrence of pale blue sclerae. The sclerae are abnormally thin, and for this reason the pigmented choroid shows through and produces the bluish color. However, the appearance of blue sclera is not confined to this disease since it may also be seen in osteopetrosis, fetal rickets, Turner syndrome, Paget’s disease, Marfan syndrome, and Ehlers- Danlos syndrome, as well as in normal infants. While the blue sclerae are a prominent sign in this disease, they are not invariably present. In a series of 42 patients reported by Bauze and his associates, 12 of the pat...

 # Radiographic finding in Pindborg tumor:  a. Sun-burst appearance  b. Onion-peel appearance  c. Driven-snow appearance  d. Cherry-blossom appearance  The correct answer is C. Driven snow appearance. A calcifying epithelial odontogenic tumor (Pindborg tumor) may show considerable radiographic variation. In some cases, the lesion appears as either a diffuse or a well-circumscribed unilocular radiolucent area, while in other cases there may appear to be a combined pattern of radiolucency and radiopacity with many small, irregular bony trabeculae traversing the radiolucent area in many directions, producing a multilocular or honeycomb pattern. Scattered flecks of calcification throughout the radiolucency have given rise to the descriptive term of a ‘driven snow’ appearance. In some instances, the lesion is totally radiolucent and is in association with an impacted tooth, thus leading to a mistaken clinical diagnosis of a dentigerous cyst. 

  # The cyst with the highest recurrence rate is:  A. Keratocyst B. Periapical cyst C. Nasoalveolar cyst D. Globulomaxillary cyst The correct answer is A. Keratocyst. In 1967, Toller suggested that the OKC may best be regarded as a benign neoplasm rather than a conventional cyst based on its clinical behavior. The WHO has reclassified the lesion as a tumor based on several factors, that formed the basis of this decision. Behavior: The KOT is locally destructive and has a high recurrence rate. Histopathology: The basal epithelial layer of KOT shows proliferation and budding into the underlying connective tissue in the form of daughter cysts and mitotic figures are frequently found in the suprabasal layers of the lesional epithelium. 

 # Dentigerous cyst is suspected if the follicular space is more than:  a. 2-3 mm  b. 3-4 mm  C. 1-2 mm  d. More than 5 mm  The correct answer is D. More than 5 mm. One of the most difficult differential diagnoses to make is between a small dentigerous cyst and a hyperplastic follicle. A cyst should be considered with any evidence of tooth displacement or considerable expansion of the involved bone. The size of the normal follicular space is 2 to 3 mm. If the follicular space exceeds 5 mm, a dentigerous cyst is more likely. If uncertainty remains, the region should be reexamined in 4 to 6 months to detect any increase in size or any influence on surrounding structures characteristic of cysts. Reference: Oral radiology Principles and Interpretation, 7th Edition Stuart C. White, Michael J. Pharoah

 # Which one of the following conditons is least likely to be associated with an increased risk of oral cancer?  a. Actinic Cheilosis  b. Erythroplakia  c. Leukoedema  d. Leukoplakia  The correct answer is C. Leukoedema.  Leukoedema is a white and veil‐like alteration of the oral mucosa that is merely considered a normal variant. The condition is often encountered bilaterally in the buccal mucosa and sometimes at the borders of the tongue. Leukoedema is less clinically evident after stretching the mucosa, but reappears after this manipulation is discontinued. Reference: Burket's Oral Medicine

 # Disadvantages of using a GRID is:  a. Increased patient exposure  b. Decreased Patient exposure  c. Increased fogging of the film  d. Increased secondary radiation  The correct answer is A. Increased patient exposure.  Although radiographic grids reduce scattered radiation and improve contrast and resolution, they result in higher patient exposure. Cephalometry does not require the use of grids. However, grids could improve the radiographic appearance of fine structures, such as trabecular architecture, and aid in the diagnosis of disease. Reference: Oral radiology Principles and Interpretation, 7th Edition Stuart C. White, Michael J. Pharoah

 # The maximum penetration among the following is seen with which ray:  a. Alpha  b. Beta  c. Gamma  d. Electron Beam  The correct answer is C. Gamma. Gamma (γ) rays originate in the nuclei of radioactive atoms. They typically have greater energy than x rays. In contrast, x rays are produced outside the nucleus and result from the interaction of electrons with large atomic nuclei in x-ray machines. The higher energy types of radiation in the electromagnetic spectrum— ultraviolet rays, x rays, and γ rays—are capable of ionizing matter. Some properties of electromagnetic radiation are best explained by quantum theory, whereas others are most successfully described by wave theory.

 # The most unwanted side effect seen with Herbst appliance is: A. Lower incisor proclination B. Frequent breakage of the appliance C. Downward rotation of palate D. Mandible rotate anticlockwise The correct answer is A. Lower incisor proclination. The most unwanted side effects seen with Herbst appliance are:  - More chance of labial tipping as well as proclination of mandibular incisors - Retrusion of maxillary incisors Reference: Pancherz H. Treatment of Class II malocclusions by jumping the bite with the Herbst appliance. A cephalometric investigation. Am J Orthod. 1979;76(4):423–442.

 # Salivary gland stone most commonly involves:  a. sublingual gland  b. Submandibular gland  c. Parotid gland  d. Lingual glands  The correct answer is B. Submandibular gland.  Sialoliths (salivary calculi or salivary stones) are calcified organic masses that form within the secretory system of the salivary glands. Although the exact mechanism of sialolith formation has not been established, it has been proposed that microcalculi are frequently formed in salivary ducts during periods of secretory inactivity.  Sialoliths occur most commonly in the submandibular glands (80–90%), followed by the parotid (5–15%) and sublingual (2–5%) glands, and only very rarely occur in the minor salivary glands. Spontaneous secretion in the minor and sublingual salivary glands may provide continuous salivary flow, thereby preventing stasis. The higher rate of sialolith formation in the submandibular glands is due to: (1) the torturous course of Wharton’s duct; (2) ...

 # A patient on warfarin sodium following myocardial infarction reports for an oral surgical procedure. Which one of the following laboratory tests should be preferred to ascertain the fitness?  a. Prothrombin time  b. Torniquet time  c. clotting time  d. bleeding time  The correct answer is A. Prothrombin time. The PT and INR tests measure the time it takes for blood to clot by forming thrombin. They evaluate the extrinsic and common coagulation pathways, screening for the presence or absence of fibrinogen (F I), prothrombin (F II), and F V, F VII, and F X. The normal range of PT is approximately 11–13 seconds. Because of individual laboratory reagent variability and the desire to be able to reliably compare the PT from one laboratory with that from another, the PT test is commonly reported with the INR. The INR, introduced by the World Health Organization in 1983, is the ratio of PT that adjusts for the sensitivity of the thromboplastin reagents, such tha...

 # Bremsstrahlung refers to:  a. the primary source of X-rays from an X-ray tube  b. Characteristic radiation emitted when an electron is displaced from the outer shell of a tungsten atom in the target  c. the electromagnetic spectrum  d. particulate radiation  The correct answer is: A. a. the primary source of X-rays from an X-ray tube.  BREMSSTRAHLUNG RADIATION: The sudden stopping or slowing of high-speed electrons by tungsten nuclei in the target produces bremsstrahlung photons, the primary source of radiation from an x-ray tube. (Bremsstrahlung means “braking radiation” in German.)

 # Multiple punched-out radiolucencies is a feature of:  a. Multiple Myeloma  b. Thalassemia  c. Fibrous Dysplasia  d. Ewing's Sarcoma  The correct answer is A. Multiple myeloma. The periphery of multiple myeloma lesions is well-defined but not corticated; it lacks any sign of bone reaction. The lesions have been described as appearing “punched out.” However, many appear ragged and even infiltrative. Some lesions have an oval or cystic shape. Untreated or aggressive areas of destruction may become confluent, giving the appearance of multilocularity.

 # Bleeding time is prolonged in: A. Hemophilia B. Von willebrand disease C. Telangiectasia D. Henoch Schonlein purpura  The correct answer is B. Von Willebrand disease. Von Willebrand disease (VWD) is the most common hereditary blood-clotting disorder in humans. An acquired form can sometimes result from other medical conditions. It arises from a deficiency in the quality or quantity of von Willebrand factor (VWF), a multimeric protein that is required for platelet adhesion. It is known to affect several breeds of dogs as well as humans. The three forms of VWD are hereditary, acquired, and pseudo or platelet type. The three types of hereditary VWD are VWD type 1, VWD type 2, and VWD type 3. Type 2 contains various subtypes. Platelet type VWD is also an inherited condition. The various types of VWD present with varying degrees of bleeding tendency, usually in the form of easy bruising, nosebleeds, and bleeding gums. Women may experience heavy menstrual periods and blood loss d...

 # " Hair-on-end" appearance in a skull roentgenogram is seen in: a. Fibrous dysplasia  b. Thalassemia  c. Garre's Osteomyelitis  d. Paget's Disease  The correct answer is B. Thalassemia. Similar to sickle cell anemia, the features of thalassemia generally result from hyperplasia of the ineffective bone marrow and its subsequent failure to produce normal red blood cells. However, these changes are usually more severe than with other anemias. There is a generalized radiolucency of the long bones with cortical thinning. In the skull, the diploic space exhibits marked thickening, especially in the frontal region. The skull also shows a generalized granular appearance, and occasionally a “hair-on-end” effect may develop.

 # A 3 year old patient has extensive vesicles on lip, tongue, oral mucous membrane. After 2-4 days vesicles rupture at followed by pseudo membrane formation and also some dermal lesions are seen. What will be the diagnosis?  a. Herpetic stomatitis  b. Erythema multiforme  c. ANUG  d. Steven-Johnson Syndrome  The correct answer is B. Erythema multiforme.  Erythema multiforme (EM) is acute, self‐limited, inflammatory mucocutaneous disease that manifests on the skin and often oral mucosa, although other mucosal surfaces, such as the genitalia, may also be involved. It represents a hypersensitivity reaction to infectious agents (majority of cases) or medications. In general, EM is classified as EM minor if there is less than 10% of skin involvement and there is minimal to no mucous membrane involvement, whereas EM major has more extensive but still characteristic skin involvement, with the oral mucosa and other mucous membranes affected.

 # Three inherent characteristics of a radiographic film: a. density, distortion, contrast  b. sharpness, contrast, density  c. definition, sharpness, penumbra  d. distortion, detail, sharpness  The correct answer is: B. Sharpness, contrast, density. Image quality describes the subjective judgment by the clinician of the overall appearance of a radiograph. It combines the features of density, contrast, latitude, sharpness, resolution, and perhaps other parameters.

 # Use of intensifying screen is: a. to decrease scattered radiation  b. to decrease patient radiation  c. to increase contrast  d. to increase number of photons striking the anode filament  The correct answer is B. To decrease patient radiation. The presence of intensifying screens creates an image receptor system that is 10 to 60 times more sensitive to x-rays than the film alone. Consequently, the use of intensifying screens substantially reduces the dose of x radiation to the patient. Intensifying screens are used with films for virtually all extraoral radiography, including panoramic, cephalometric, and skull projections.