Teeth mostly involved in Hypercementosis

# Hypercementosis is the excessive deposition of secondary cementum on the roots. Any tooth may be involved, however, which teeth are most frequently involved?
A. Molars
B. Incisors
C. Premolars
D. Canines

The correct answer is C. Premolars.

Hypercementosis is often confined to the apical half of the root but, in some instances, may involve the entire root. In a large majority of instances, it affects vital teeth, is not associated with any one particular systemic disease, and may be regarded as a dental anomaly.

lt may be seen when a tooth has lost its antagonist or when there is a chronic inflammation of the tooth. The premolars are most frequently involved. Next in frequency are the first and second molars.

Hypercementosis produces no significant clinical signs or symptoms indicative of its

presence. It is seen radiographically as a bulbous enlargement that has surrounding it a

continuous and unbroken periodontal membrane space and a normal lamina dura.

Death in Ludwig's angina occurs due to

# Death in Ludwig's angina occurs due to: (MAN -2K)
A. Sepsis
B. Respiratory obstruction
C. Cavernous sinus thrombosis
D. Carotid blow-out

The correct answer is B. Respiratory obstruction.

In Ludwig's angina there is progressive
dyspnoea due to backward spread of infection.

If not treated, it results in edema of glottis and causes complete respiratory obstruction.

What is herd immunity?

# At what point is herd immunity to a given disease observed?
A. After 100% of a population has developed a primary immune response
B. After antibiotics have treated all known cases of disease in a population
C. After 100% of a population has developed a secondary immune response
D. Immediately after 100% of a population has been Immunized
E. After enough people in a population have developed a primary immune response so that spread of an infectious agent is curtailed

The correct answer is E. After enough people in a population have developed a primary immune response so that spread of an infectious agent is curtailed. 

Herd immunity does not require that 100%

of a population be immune. Herd immunity

requires that enough people in the population have elicited memory cells.

Should the pathogen enter the population,

the number of people infected will be small

because the immunized population will not

be able to contract or spread the infection

to the non-immunized population. This

keeps the number of pathogens to a

minimum, for the protection of all.

Extend the life of a Tungsten Carbide bur

# To extend the life of a tungsten carbide bur, the bur should...
A. Be moving slow before contacting tooth structure
B. Be sterilized with heat sterilization
C. Contact tooth structure before rotating
D. Be moving fast before contacting tooth structure

The correct answer is D. Be moving fast before contacting tooth structure.

The lifespan of a tungsten carbide bur can
be extended by bringing the bur up to speed  before contacting tooth structure, because it decreases the friction between the bur and the tooth structure thereby decreasing damage to the bur and the pulp.

Sufficient rotating speed makes the cutting
edge of the bur more efficient even with
using light pressure.

Heat sterilization corrodes the carbon steel
and anneals the cutting edge of the bur.

Rubber Dam

# In Which dental procedure is a rubber dam most indicated?
A. Deep caries
B. Direct pulp capping
C. Indirect pulp capping
D. Preparing a crown

The correct answer is: B. Direct Pulp capping. 

In direct pulp capping, it is essential to have adequate access, visibility, and isolation of the operating field.

Direct pulp capping is indicated if a pin-point pulp exposure is made during cavity preparation.

Teeth should be properly isolated to avoid saliva and bacterial contamination during direct pulp caps.

Proper isolation of the operating field also allows proper sealing of the cavity of the tooth. 

Single most important factor in producing cariogenic plaque

# The single most important factor in producing cariogenic plaque is:
A. High amount of glucose exposure
B. High frequency of glucose exposure
C. High amount of sucrose exposure
D. High frequency of sucrose exposure

The correct answer is: D. High frequency of sucrose exposure.

High-frequency exposure to fermentable carbohydrates such as sucrose may be the most important factor in producing cariogenic biofilm and ultimately caries lesions. Frequent ingestion of fermentable carbohydrates begins a series of changes in the local tooth environment, essentially changing the composition of the biofilm, thus favoring the growth of highly acidogenic bacteria that eventually leads to caries lesion formation. In contrast, when ingestion of fermentable carbohydrates is severely restricted or absent, biofilm growth typically does not lead to caries lesions.

Sucrose in particular allows the formation of extracellular polysaccharides, which render the biofilm viscous and sticky. Because the eventual metabolic product of cariogenic diet is acid, in addition to caries lesions the exposure to acidity from other sources (e.g., dried fruits, fruit drinks, or other acidic foods and drinks) also may result in dental erosion.

Liquid system of glass ionomer restorative material

# The liquid system of glass ionomer restorative material is essentially:
A. Polyalkanoic acid
B. Phosphoric acid
C. Polyacrylic-itaconic acid
D. Hydrochloric acid

The correct answer is C. Polyacrylic-itaconic acid.

COMPOSITION OF GLASS IONOMER CEMENTS

Powder/liquid materials

Powder -  Sodium aluminosilicate glass with about 20% CaF and other minor additives

Liquid - Aqueous solution of acrylic acid/itaconic acid copolymer or Aqueous solution of maleic acid polymer or maleic/acrylic copolymer and Tartaric acid in some products to control setting characteristics

Powder/water materials

Powder - Glass (as above) + vacuum-dried polyacid (acrylic, maleic or copolymers)

Liquid - Manufacturers supply a dropper bottle which the operator fills with water or The manufacturer supplies a dilute aqueous solution of tartaric acid