Dentosphere : World of Dentistry

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. 

# I.V. Diazepam in a patient on a dental chair can cause: [AIIMS 2007 NOV] A. Tinel’s Sign B. Verrill’s Sign C. Bell’s sign D. Coleman’s sign The correct answer is B. Verrill's Sign. Verrill's  sign has 3 Symptoms which indicate  the correct level after  diazepam sedation. - 50% eyelid ptosis - Blurring of vision - Slurring of speech  Verrill's Sign # Tinel's Sign: Tinel sign was used earlier as an indicator of the start of the nerve regeneration. It is elicited by percussion over the divided nerve, which result in tingling sensation in part supplied by peripheral section. # Coleman's sign: Seen in mandibular fractures. Ecchymosis in the lingual sulcus is pathognomic of mandibular fracture.  # Bell's Sign: Bell's phenomenon (also known as the palpebral oculogyric reflex) is a medical sign that allows observers to notice an upward and outward movement of the eye, when an attempt is made to close the eyes. The upward move...

# Local anesthetic with adrenaline if injected intravenously, what will be the result? ( AIIMS 2014, AIPG 2013) A. Hypertension with Tachycardia B. Hypotension with Tachycardia C. Hypotension with Bradycardia D. Hypertension with Bradycardia The correct Answer is: A. Hypertension with Tachycardia.  # In a hypertensive patient on B-blockers, an injection of Local anesthesia + Adrenaline will cause: A. Hypertension and Tachycardia B. Hypertension and Bradycardia C. Hypotension and Tachycardia D. Hypotension and Bradycardia The correct answer is B. Hypertension and Bradycardia. There are two separate drug interaction considerations with local anesthetics, the anesthetic itself and the vasoconstrictor. Hypertensive events have been documented in patients taking B blockers, Furazolidone, Tricyclic antidepressants, methyl dopa, and the antihypertensive drugs guanethidine and Rauwolfia alkaloids. Beta blocker interactions are potentially the most serious one...

Mal-aligned teeth or crooked teeth are problematic not only aesthetically but also from a health point of view. Irregularly placed teeth when present are difficult to clean and maintain hygiene, affect the speech, alters the facial profile and decreases the quality of smile and overall confidence of the person. Let's see what are the causes of having crooked teeth. 1. Heredity and Evolution During the course of evolution, the size of man's jaw has been decreasing gradually. Before thousands of years it is believed that human's used to have long jaws and even four molars. Present day human has smaller jaws and even third molars are impacted and need to be removed surgically these days. Also, heredity also plays an important in proper alignment of teeth. If any of the parents have crooked tooth, the offsprings may also inherit the same. 2. Tooth size arch length discrepancy When the jaws are smaller and they cannot accommodate all the teeth in the arch properly, the...

The correct answers are highlighted in green. # The arithmetical average of a number of observations is called :  A. Mean   B. Median  C. Range  D. All of the above # Which of the following correlates highest correlation between variables ?   A. r= + 0.25   B. r= + 0.5   C. r= - 0.75   D. r= + 2