Dentosphere : World of Dentistry

# Most common reason for the removal of impacted mandibular third molars is:  A. Referred pain  B. Recurrent pericoronitis  C. Chronic periodontal disease  D. Orthodontic treatment The correct answer is B. Recurrent Pericoronitis Pericoronitis is an inflammatory lesion occurring around the impacted or partially erupted tooth. An incomplete eruption of the tooth provides a large stagnation area for food debris under the gingival flap. This becomes infected easily and results in inflammation of the pericoronal flap. It exhibits chronic inflammation for a long period. If the debris and bacteria are deeply entrapped, an abscess may form which is called a pericoronal abscess. It is a mixed infection and various bacteria of the dental plaque (particularly anaerobes) play a significant role in the development of pericoronitis. Clinical Features: The mandibular third molar is the commonly involved tooth. Pain and swelling of the pericoronal tissue around the aff...

# In lead poisoning, gingival discoloration presents as: A. Blue black line B. Yellow line C. Grayish black line D. Steel gray line # Dilaceration occurs due to: A. Trauma to the tooth germ during root development B. Abnormal displacement of the tooth germ during root development C. Abnormal displacement of enamel epithelium during tooth development D. Abnormal displacement of ameloblasts during tooth development

CLICK HERE TO REVEAL ALL ANSWERS AFTER YOU HAVE MARKED ALL YOUR ANSWERS IN A SEPARATE PAPER AND CHECK YOUR SCORE. # 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

# Radiographically, driven snow appearance is seen with: A. Adenomatoid odontogenic tumor B. Calcifying odontogenic cyst C. Calcifying epithelial odontogenic tumor D. Keratocyst The correct answer is C. Calcifying Epithelial Odontogenic Tumor - Scattered flecks of calcification throughout the radiolucency has given rise to the descriptive term driven snow appearance. - Lesion appears as diffuse or well circumscribed unilocular radiolucency. - Combined radiolucency and radioopacity with irregular bony spicules producing honeycomb pattern - Scattered flecks of calcification give driven snow appearance - Sometimes, lesion is totally radiolucent and in association with unerupted tooth

ZONES OF DENTINAL CARIES ZONE 1 Normal Dentin Zone 2 Subtransarent Dentin Zone of demineralization (by acid from caries) Damage to the odontoblastic process is evident. However, no bacteria are found in the zone. Stimulation of the dentin produces pain, and the dentin is capable of remineralization. Zone 3 Transparent dentin Softer than normal dentin Further loss of mineral from the intertubular area. Stimulation of this region produces pain. There are no bacteria present. The collagen cross-linking remains intact in this zone, can serve as a template for remineralization. The intact collagen of the intertubular dentin, and thus this region remains capable of self-repair, provided the pulp remains vital. Zone 4 Turbid dentin Turbid dentin is the zone of bacterial invasion  Widening and distortion of the dentinal tubules which are filled with bacteria. There is very little mineral present and the collagen in this zone is irreversib...

# Whenever the caries cone in enamel is larger or at least the same size as that in dentin, it is called as: A. Residual caries B. Recurrent caries C. Forward caries D. Backward caries Forward Caries. Forward caries is where the caries cone in enamel is larger or at least the same size as that in dentin. Backward Caries. When the spread of caries along the DEJ exceeds the caries in the contiguous enamel, caries extends into this enamel from the junction. Ans is C: Forward caries (Ref: Sturdevant's Art and science of operative dentistry 4th ed., p 274)

# DPT vaccine does not provide immunity against: A. Tetanus B. Diphtheria C. Polio D. Whooping cough The correct answer is C. Polio. The vaccine DPT stands for Diphtheria, Pertusis (Whooping cough) and Tetanus.