Dentosphere : World of Dentistry

# The most common reason why hyperplastic tissue is removed during the construction of a complete denture is that: a) It interferes with the arrangement of the teeth b) It is unaesthetic to construct a denture on a hyperplastic tissue c) It interferes with the stability of the denture d) All of the above The correct answer is C. It interferes with the stability of the denture. The most important reason for the treatment of hyperplastic tissue before the construction of complete or removable partial dentures is to provide a firm, stable base for the denture. 

# The amount of functional cusp reduction required for metal-ceramic crown is - a) 1.0 - 2.5 mm b) 1.5 - 2.0 mm c) 2.0 - 2.25 mm d) 1.85 - 2.10 mm The correct answer is B. 1.5 -2.0 mm.  Metal ceramic restorations require a 1.5 - 2 mm reduction in the functional cusp and 1.0 - 1.5mm reduction in the non-functional cusp. 

# Best method to remove gutta-percha in retreatment procedures: A. Hand instrumentation B. Automated instrumentation C. Rotatory instruments D. Ultrasonic instruments The correct answer is A. Hand instrumentation The coronal portion of gutta-percha obturations should always be drilled out, preferably by means of endodontic drills such as the Gates-Glidden or Peeso. Gutta-percha may be dissolved (solvent technique) or removed in its solid form (Solid gutta-percha techniques). Dissolving avoids the use of excessive force in the negotiating of gutta-percha-obturated canals. Extrusion of solvent into the periapical tissues should be prevented. Solvents of gutta-percha: Gutta-percha is soluble in chloroform, ethyl chloroform, carbon disulfide, carbon tetrachloride, benzene, xylene, eucalyptol oil, halothane, and rectified white turpentine. Retreatment of solid objects other than gutta-percha, either a silver point or a fragment of an instrument or post, cannot ...

# Endodontic retreatment: A. Is as technically challenging as original treatment B. Has a poorer prognosis than original treatment C. Is performed only on endodontic failures D. Has different objectives than primary treatment The correct answer is B. has a poorer prognosis than the original treatment

# In restoring an endodontically treated tooth for post core, an absolute minimum of apical fill of gutta percha to be left over to prevent leakage is: A. 1 mm B. 2 mm C. 3 mm D. 4 mm The correct answer is D. 4mm Since there is greater leakage when only 2-3 mm of Gutta-percha is present, 4-5 mm should be retained apically to ensure an adequate seal. Although studies indicate that 4 mm produce an adequate seal, stopping precisely at 4 mm is difficult, and radiographic angulation errors could lead to retention of less than 4 mm. Therefore, 5 mm of gutta-percha should be retained apically. 

# Concentration of EDTA used during biomechanical preparation (BMP) is: A. 20% at pH 7.4 B. 15% at pH 5.0 C. 15% at pH 7.3 D. 25% at pH 7.4 The correct answer is C. 15% at pH 7.3 EDTA has a property of chelate formation with calcium salts. Disodium salt of EDTA is used in endodontic therapy for dissolving pulp stones. 

# Length of a Peeso reamer is: A. 28-32 mm B. 30-35 mm C. 35-40 mm D. 40-45 mm The correct answer is A. 28-32 mm - Standard Peeso reamer is of 32 mm length. - Short Peeso reamer is of 28 mm length.

# Which of the following is called cardiac glycosides? A. Digitalin B. Belladonna C. Reserpine D. Colchicum Cardiac glycosides are a class of organic compounds that increase the output force of the heart and increase its rate of contractions by acting on the cellular sodium-potassium ATPase pump. Their beneficial medical uses are as treatments for congestive heart failure and cardiac arrhythmias; however, their relative toxicity prevents them from being widely used. Cardiac glycosides can be more specifically categorized based on the plant they are derived from, as in the following list. For example, cardenolides have been primarily derived from the foxglove plants Digitalis purpurea and Digitalis lanata, while bufadienolides have been derived from the venom of the cane toad Bufo marinus, from which they receive the “bufo” portion of their name. Cardiac glycosides have long served as the main medical treatment to congestive heart failure and cardiac arrhythm...

# The middle meningeal artery: (MAN -95) a) Enters the skull through the foramen ovale b) Supplies the superolateral surface of the ipsilateral cerebral hemisphere c) Runs a subdural course within the cranial cavity d) Gives an interior branch which runs deep to the pterion The correct answer is D. Gives an interior branch which runs deep to the pterion The middle meningeal artery enters the middle cranial fossa through the foramen spinosum. In middle cranial fossa, it has an extradural course and divides into anterior frontal branch and posterior parietal branch. The frontal branch is closely related to the motor area of the cerebral cortex. It is the commonest source of extradural hemorrhage and results in hemiplegia of the opposite side. The parietal branch is closely related to the cerebrum and its involvement result in contralateral deafness. 

# Which one of the following is a junction of frontal, parietal, temporal and greater wing of sphenoid bone?   A. Pterion  B. Lambda  C. Vertex  D. Inion # A non synovial joint with dense connective tissue between two bony surfaces is termed as:  A. Synchondrosis  B. Syndesmosis  C. Symphysis  D. Suture

14th MARCH 2019 B.P. Koirala Institute of Health Sciences, Dharan, Nepal 5th year BDS FINAL EXAMINATION, MARCH 2019 Paper - IV  (ORAL & MAXILLOFACIAL SURGERY) Time - 2 Hours  Total Marks: 80 SHORT ANSWER QUESTIONS SECTION - 'A' Maximum Marks - 40 1. Explain the pathophysiology of osteomyelitis of jaws.   (4) 2. Discuss the clinical features of trigeminal neuralgia and enlist different treatment options. (2+3=5) 3. Enlist FOUR clinical features of zygomatic arch fracture. Add a note on Gillies temporal approach to indirect reduction. (2+3=5) 4. Enlist the clinical test to diagnose oro-antral communication and add a note on management of oroantral communication. (2+4=6) 5. Discuss briefly on different types of dislocation and enumerate the surgical procedures for the management of chronic recurrent temporomandibular joint dislocation . (3+3=6) 6. Mention the difference between ridge extension and ridge augmentation procedure ba...

# Moth eaten appearance is seen in all except: A. Osteomyelitis B. Hemorrhagic cyst C. OKC D. Osteosarcoma The correct answer is C. OKC 'Moth eaten appearance' is seen in lesions of bone which shows lytic activity.  Seen in: - Osteomyelitis - Acute suppurative and chronic both - Osteosarcoma - Osteoradionecrosis - Ewing Sarcoma - Langerhans cell histiocytosis - Hemorrhagic cyst

# A radiolucency seen between the maxillary central incisors is most commonly due to: A. Periapical cyst B. Nasopalatine cyst C. Globulomaxillary cyst D. Nasoalveolar cyst The correct answer is B. Nasopalatine cyst Nasopalatine cyst (Incisive canal cyst) - Most common fissural cyst, usually asymptomatic, may complain of tender swelling of palate. Radiographic characteristics- well demarcated round, oval or heart shaped radiolucency between and above maxillary central incisors; rarely just lateral to the midline; lesion crosses midline, teeth are vital. 

# The dentin desensitizing agents that acts by precipitating proteins in dentinal tubular fluid is: (MHCET 2014) A. Strontium chloride B. Potassium oxalate C. Fluoride D. Hydroxyethyl methacrylate The correct answer is A. Strontium chloride. After professional diagnosis, dentinal hypersensitivity can be treated simply and inexpensively by home use of desensitizing dentifrices. Strontium Chloride Dentifrices Ten percent strontium chloride desensitizing dentifrices are found effective in relieving the pain of tooth hypersensitivity. Potassium Nitrate Dentifrices Five percent potassium nitrate dentifrices are found to alleviate pain related to tooth hypersensitivity. Fluoride Dentifrices Sodium monofluorophosphates dentifrices are effective mode of treating tooth hypersensitivity. Strontium chloride is the most important constituent in home care dentifrices intended to be used for the treatment of dentinal hypersensitivity. Topical applicatio...

# Which of the following are true about direct pulp capping? A. Mechanically exposed teeth have a greater success rate than carious exposures B. Final restorative materials do not affect success C. Generally, individual teeth involved in a fixed prosthesis are candidates for direct pulp capping D. All of the above The correct answer is A.  Mechanically exposed teeth have greater success rate than carious exposures.

# The ‘FLUORIDE BOMBS’ is related to: A. A fluoride  capsule with high ppm of fluoride varnish B. A hypoplastic lesion on tooth seen in fluorosis areas C. Undiagnosed hidden caries D. Procedure to treat rampant caries The correct answer is C. Undiagnosed hidden caries. Occult or hidden caries is used to describe such lesion which is not clinically diagnosed but detected only on radiographs. Occult lesions are seen with low caries rate which is suggestive of increased fluoride exposure. It is believed that increased fluoride exposure encourages remineralization and slows down the progress of the caries in the pit and fissure enamel while the cavitation continues in dentin, and the lesions become masked by a relatively intact enamel surface. These hidden lesions are called 'fluoride bombs' or fluoride syndrome.

# Calcium hydroxide is advocated as an inter appointment intracanal medication because of: A. Its ability to dissolve necrotic tissue B. Its antimicrobial property C. Its ability to stimulate hard tissue formation D. Its powerful bleaching effect The correct  answer is B. Its antimicrobial property.  Most studies report culture reversals during the interappointment period when active antibacterial dressing is not used in the root-canal system between appointments. The reversals are due to regrowth of residual bacteria or recontamination by bacterial leakage around the access cavity dressing.  Classical and well-controlled studies (Sundqvist’s group) evaluated the effect of various root-canal treatment procedures on the microbiota both qualitatively and quantitatively. They tested the effect of mechanical preparation, saline or sodium hypochlorite irrigation (0.5%, 5.0%, 5.0% with EDTA), the addition of ultrasonic activation to the irrigation and calc...