.The most resistant filling materials to fill class IV cavities are: A. Resins with silicone dioxide (SiO2) B. Resins with glass or quartz C. Silico-phosphate D. Silicates

.The most resistant filling materials to fill class IV cavities are:
A. Resins with silicone dioxide (SiO2)
B. Resins with glass or quartz
C. Silico-phosphate
D. Silicates
by

1 Answer

Answer :

B. Resins with glass or quartz
by

Related questions

.In regard to the glass of quartz particles of filling restorative resin; the microfill resins tend to have, A. A higher coefficient of thermal expansion and a higher crashing strength B. A higher coefficient of thermal expansion and a lower crashing strength C. A lower coefficient of thermal expansion and a higher crashing strength D. A lower coefficient of thermal expansion and a lower crashing strength

Description : .In regard to the glass of quartz particles of filling restorative resin; the microfill resins tend to have, A. A higher coefficient of thermal expansion and a higher crashing strength B. ... and a higher crashing strength D. A lower coefficient of thermal expansion and a lower crashing strength

Last Answer : B. A higher coefficient of thermal expansion and a lower crashing strength

Rank the following impressions materials according to their flexibility A. Alginate> Polysulphide> Silicone> Zinc Oxide Eugenol B. Silicone> Alginate> Polysulphide> Zinc Oxide Eugenol C. Alginate> Polysulphide> Zinc Oxide Eugenol>Silicone D. Alginate> Silicone> Polysulfide> Zinc Oxide Eugenol E. Alginate> Zinc Oxide Eugenol> Silicone> Polysulphide 300.Denture resins are usually available as powder and liquid that

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Last Answer : D. Alginate> Silicone> Polysulfide> Zinc Oxide Eugenol

.In which class of cavities do composite restorations show most durability: A. I B. II C. IV D. III E. V

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Last Answer : D. III

Glass is made of the mixture of-------? A. Quartz and Mica B. Sand and Salt C. Sand and Silicates (Answer) D. None of these

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Last Answer : C. Sand and Silicates (Answer)

Why can Class IV gold not be used in cavity as a filling material: A. Can not be polished “burnished” B. The corrosive properties

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(3) preventing rapid setting of cement Explanation: Portland cement clinker is a hydraulic material which shall consist of at least two-thirds by mass of calcium silicates, the remainder consisting of aluminium- and ironcontaining clinker phases and other compounds. The ratio of CaO to SiO2 shall not be less than 2.0. The magnesium oxide content (MgO) shall not exceed 5.0% by mass. Cement sets when mixed with water by way of a complex series of chemical reactions still only partly understood.

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Last Answer : Milk is a colloidal system in which: (1) Water is dispersed in fat (2) Fat is dispersed in water (3) Fat and water are dispersed in each other (4) Fat is dissolved

The polysulfide rubber impression materials are: A. Not sensitive to temperature when curing B. Quite sensitive to temperature when curing C. Less sensitive to temperature than silicone rubber D. The same sensitivity to temperature as silicone rubber E. None of the above

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Last Answer : B. Quite sensitive to temperature when curing

Inside the ____ is a gas generator containing a mixture of NaN3 (Sodium Azide), KNO3 (Potassium Nitrate) and SiO2 (Silicon Dioxide). When the undesired event happens, an electric circuit is turned on by a sensor, and a series of chemical reactions generate nitrogen gas that fills ____ in 20 to 30 milliseconds. Fill up the blank

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Last Answer : Air-bags in automobiles.

Pick up the correct statement from the following: (A) The free quartz suddenly expands at a temperature lower than 600°C (B) The lime stone resists fire upto about 800°C and at higher temperature it splits into CaO and CO2 (C) The sand stone with silicates resist a fire in a better way (D) All the above

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Last Answer : Answer: Option D

Silicone resins, which are highly water repellent and has good heat resistance cannot be used (A) As room temperature adhesive (B) As grease & lubricant

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Patient has hot and cold sensation and pain on percussion after the filling of class III Cavity with GIC base and composite. What will be possible cause – 1) bacterial microleakage 2) mechanical trauma of cavity cutting 3) Exothermic reaction while setting GIC

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At what angle to the external surface should proximal cavosurface walls in Class II preparation for the reception of an amalgam filling be finished: A. Acute angle B. Right angle C. Obtuse angle D. 45 angle

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Last Answer : C. Obtuse angle

Before filling a class V abrasion cavity with GIC you should(+adc March07) A. Clean with pumice, rubber cup, water and weak acid B. Dry the cavity thoroughly before doing anything C. Acid itch cavity then dry thoroughly

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Last Answer : A. Clean with pumice, rubber cup, water and weak acid

Which of the following is not a dielectric material? (A) Cotton, silk and paper (B) Asbestos, glass, porcelain and mica (C) Rubber and polymeric resins (D) All refractory materials

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Last Answer : Option C

In calculus formation, the epitaxic concept is one of the theories. Which of the following is true: a. Mineralisation occurs when calcium and phosphate content is high. b. The presence of matrix would start initial formation of nucleus. c. The amorphous materials would convert to calcium phosphate and hydroxy phosphate.

Description : In calculus formation, the epitaxic concept is one of the theories. Which of the following is true: a. Mineralisation occurs when calcium and phosphate content is high. b. The presence of ... of nucleus. c. The amorphous materials would convert to calcium phosphate and hydroxy phosphate.

Last Answer : b. The presence of matrix would start initial formation of nucleus.

In calculus formation the epitaxic concept is one of the theories. Which of the following is true: A. Mineralisation occurs when calcium and phosphate content is high B. The presence of matrix would initiate the formation of the nucleus C. The amorphous materials would convert to calcium phosphate and hydroxy

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In 3rd generation dentin bonding agents, HEMA (Hydroxyethylmethacrylate) is 1. a hydrophilic monomer that wets the dentinal surface 2. a hydrophilic resin that forms a ”hybrid” layer by chemically reacting the intertubular dentin. 3. a hydrophilic monomer that alters collagen to promote cross linking of collagen to dentin. 4. a bifunctional molecule resin that copolymerizes to bis-GMA resins. a. 1,2 b. 1,4 c. 2,3 d. 1,3 e. 3,4

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Last Answer : b. 1,4

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The effect of the temperature rising above 100ºC on heat-cured denture-base acrylic resins is: A. Produces porosity on the external portion of the resin. B. Produces porosity on the internal portion of the resin. C. Produces porosity on the surface of the resin. D. Prevents porosity on the interior of the resin

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Last Answer : B. Produces porosity on the internal portion of the resin.

What is an important requisite for fillers in dental composite restorative resins in load bearing areas: A. Sub micro sized particles B. High coefficient of thermal expansion C. High in content (High filler)

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Last Answer : C. High in content (High filler)

Retention for occlusal amalgam cavities in premolars is BEST provided by A. Slightly undercutting of walls with inversed cone bur B. Mesial and distal undercuts C. Buccal and lingual undercuts

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Last Answer : C. Buccal and lingual undercuts

Self polymerising acrylic resins differ from heat cured resins because they exhibit: A. Higher molecules weight B. Higher content of residual monomers

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Last Answer : C. Resilient in long run

Which impression material should NOT be kept in water within on hour: (in another paper it was: 30 mins before pouring) A. Polyether B. Condensation silicone C. Polyvinyl silicone

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Last Answer : A. Polyether 

An impression with elastomer in custom tray has been taken for crown preparation; it will be two days before the impression gets to the laboratory for construction of the crown. Which impression material is preferred? A. Polyether B. Thiokol or meraptan rubber C. Condensation silicone D. Vinyl polysiloxane

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Last Answer : D. Vinyl polysiloxane

Low grade phosphate rock can be used in electrical furnace, because (A) Of the better CaO/SiO2 balance for slag formation (B) CaO content is less (C) It is cheap (D) It produces low cost product

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Last Answer : (A) Of the better CaO/SiO2 balance for slag formation

Which of the listed groups of electrical insulation materials is best suited for the highest operating temperatures? A. impregnated cotton and silk B. unimpregnated paper and cotton C. pure glass and quartz D. mica and porcelain with bonding agents

Description : Which of the listed groups of electrical insulation materials is best suited for the highest operating temperatures? A. impregnated cotton and silk B. unimpregnated paper and cotton C. pure glass and quartz D. mica and porcelain with bonding agents

Last Answer : Answer: C

Choose the optical fibre material from the given materials. a) Glass b) Plastic c) Silica d) Quartz

Description : Choose the optical fibre material from the given materials. a) Glass b) Plastic c) Silica d) Quartz

Last Answer : c) Silica

Ceramics are produced from silicates or clayish materials: Which of the following is not a ceramic material? (A) Slag cement (B) Glasses (C) Porcelain/Potteries (D) Teflon

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Last Answer : (D) Teflon

Patient reported to you 30 min after trauma to central incisor. Patient is 10 yrs old and there is traumatic exposure of pulp. What will be the line of treatment— 1) coronal pulpotomy and Ca-hydr. Base and then permanent filling 2) Ca-hydroxide base and permanent filling 3) 1-2 mm. of coronal pulp extirpated and Ca hydroxide and then permanent filling 4) Pulpectomy

Description : Patient reported to you 30 min after trauma to central incisor. Patient is 10 yrs old and there is traumatic exposure of pulp. What will be the line of treatment- 1) coronal pulpotomy and Ca-hydr. ... 3) 1-2 mm. of coronal pulp extirpated and Ca hydroxide and then permanent filling 4) Pulpectomy

Last Answer : 3) 1-2 mm. of coronal pulp extirpated and Ca hydroxide and then permanent filling

An 8 years-old child who has sustained a fracture of maxillary permanent central incisor in which 2mm of the pulp is exposed presents for treatment three hours after injury. Which of the following should be considered? a- Remove the surface 1. 2 mm of pulp tissue and place calcium hydroxide. b- Place calcium hydroxide directly on the exposed pulp. c- Pulpotomy using formocresol. d- Pulpectomy and immediate root filling. e- Pulpectomy and apexification.

Description : An 8 years-old child who has sustained a fracture of maxillary permanent central incisor in which 2mm of the pulp is exposed presents for treatment three hours after injury. Which of the ... - Pulpotomy using formocresol. d- Pulpectomy and immediate root filling. e- Pulpectomy and apexification.

Last Answer : a- Remove the surface 1. 2 mm of pulp tissue and place calcium hydroxide

A female patient comes to you complaining of persistent pain in a heavily restored central incisor; you suspect pulpitis and you have been told that she is in transit leaving by plane next day. Your treatment will be, A. Remove filling and place a sedative dressings B. Pulp extirpation and obturate with Ledermix dressings C. Prescribe analgesics and systemic antibiotic

Description : A female patient comes to you complaining of persistent pain in a heavily restored central incisor; you suspect pulpitis and you have been told that she is in transit leaving by plane ... B. Pulp extirpation and obturate with Ledermix dressings C. Prescribe analgesics and systemic antibiotic

Last Answer : B. Pulp extirpation and obturate with Ledermix dressings

A patient complains of sensitivity, on examination you find a composite filling restoring a good cavity preparation without any secondary caries; what is your next step: A. Extirpate the pulp that is obviously inflamed B. Place ZOE dressing to sedate the pulp C. Ask patient to come back in six months D. Repeat restoration

Description : A patient complains of sensitivity, on examination you find a composite filling restoring a good cavity preparation without any secondary caries; what is your next step: A. Extirpate the pulp that is obviously ... to sedate the pulp C. Ask patient to come back in six months D. Repeat restoration

Last Answer : B. Place ZOE dressing to sedate the pulp

How long would it take to notice significant reduction in radiolucency after finishing a root filling in a tooth with a periapical lesion: A. 6 months B. 1 month C. 3 months

Description : How long would it take to notice significant reduction in radiolucency after finishing a root filling in a tooth with a periapical lesion: A. 6 months B. 1 month C. 3 months

Last Answer : A. 6 months

The MAIN purpose of burnishing is: A. To help eliminating excess mercury (condensing) B. To condense margins C. Polishing of filling

Description : The MAIN purpose of burnishing is: A. To help eliminating excess mercury (condensing) B. To condense margins C. Polishing of filling

Last Answer : B. To condense margins

X rays are used in endodontic treatment to: A. Aid in the diagnosis of periapical hard tissue lesion B. Determine the number, location, shape, size and direction of roots and root canals C. Confirm the length of root canals D. Evaluate the adequacy of the complete root canal filling E. All of the above

Description : X rays are used in endodontic treatment to: A. Aid in the diagnosis of periapical hard tissue lesion B. Determine the number, location, shape, size and direction of roots and root canals C. Confirm ... root canals D. Evaluate the adequacy of the complete root canal filling E. All of the above

Last Answer : E. All of the above

What indicates for a periapical surgery: A. Where performing an endodontic treatment on existing root canal filling may lead to fracture of the root B. When root canal treatment is faulty C. When there is danger of involving other structures D. When the bony defect is so extensive that the edges of the incisors will collapse E. None of the above

Description : What indicates for a periapical surgery: A. Where performing an endodontic treatment on existing root canal filling may lead to fracture of the root B. When root canal treatment is faulty C. When ... bony defect is so extensive that the edges of the incisors will collapse E. None of the above

Last Answer : A. Where performing an endodontic treatment on existing root canal filling may lead to fracture of the root

In RCT the ideal root filling: A. Ends at the apex B. Extends beyond apex to achieve a good seal C. Ends at the dentino-cemental junction

Description : In RCT the ideal root filling: A. Ends at the apex B. Extends beyond apex to achieve a good seal C. Ends at the dentino-cemental junction

Last Answer : C. Ends at the dentino-cemental junction

The gingiva of a child is diagnosed on the basis of all of these except of: A. Contour of gingival papilla B. Sulcus depth C. Contour of Nasmyth membrane (nasmyth description of the membrane is unclear that's why the term enamel cuticle is preferred D. Tight filling of gingival collar

Description : The gingiva of a child is diagnosed on the basis of all of these except of: A. Contour of gingival papilla B. Sulcus depth C. Contour of Nasmyth membrane (nasmyth description of the membrane is unclear that's why the term enamel cuticle is preferred D. Tight filling of gingival collar

Last Answer : C. Contour of Nasmyth membrane (nasmyth description of the membrane is unclear that's why the term enamel cuticle is preferred

8 years old child who has sustained a fracture of maxillary permanent central incisor in which 2mm of the pulp is exposed; presents for treatment three hours after injury. Which of the following should be considered? M07*********** A. Remove the surface 1-2 mm of pulp tissue and place calcium hydroxide (Cvek pulpotomy, apexogenesis) B. Place calcium hydroxide directly on the exposed pulp C. Pulpotomy using formocresol D. Pulpectomy and immediate root filling E. Pulpectomy and apexification

Description : 8 years old child who has sustained a fracture of maxillary permanent central incisor in which 2mm of the pulp is exposed; presents for treatment three hours after injury. Which of the ... C. Pulpotomy using formocresol D. Pulpectomy and immediate root filling E. Pulpectomy and apexification

Last Answer : A. Remove the surface 1-2 mm of pulp tissue and place calcium hydroxide (Cvek pulpotomy, apexogenesis)

Silico-manganese steels (containing 0.7% Mn, 0.5% C and 2% Si) (A) Do not require heat treatment for any of its applications (B) Are used for leaf and coiled springs (C) Do not have good resilience properties (D) Is tempered at 850°C

Description : Silico-manganese steels (containing 0.7% Mn, 0.5% C and 2% Si) (A) Do not require heat treatment for any of its applications (B) Are used for leaf and coiled springs (C) Do not have good resilience properties (D) Is tempered at 850°C

Last Answer : (B) Are used for leaf and coiled springs

Silicone rubber is not resistant to the corrosive action of (A) Sulphuric acid (10%) (B) Sulphuric acid (95%) (C) Ether (D) Both (B) and (C)

Description : Silicone rubber is not resistant to the corrosive action of (A) Sulphuric acid (10%) (B) Sulphuric acid (95%) (C) Ether (D) Both (B) and (C)

Last Answer : (D) Both (B) and (C)

Marginal leakage at the proximal gingival cavosurface of a recently restored class II can be caused by: I. Insufficient condensation II. First proximal increment was too large III. Neglecting to wedge the matrix IV. Hand manipulation instead of mechanical V. Debris contamination A. I, II, III B. II, III, IV C. I, II, V D. None of the above E. All of the above

Description : Marginal leakage at the proximal gingival cavosurface of a recently restored class II can be caused by: I. Insufficient condensation II. First proximal increment was too large III. Neglecting to wedge the matrix IV. Hand ... III, IV C. I, II, V D. None of the above E. All of the above

Last Answer : C. I, II, V

Longest lasting resin restorations are, A. Class I B. Class II C. Class III D. Class IV

Description : Longest lasting resin restorations are,  A. Class I   B. Class II  C. Class III  D. Class IV 

Last Answer : C. Class III 

The bur should be tilted lingually when preparing the occlusal surface of class II cavity on a mandibular first premolar in order to: I. Remove unsupported enamel II. Prevent encroachment on the buccal pulp horn III. Prevent encroachment on the lingual pulp horn IV. Maintain dentinal support of the lingual cusp A. I and II B. I and III C. II and IV D. III and IV E. IV only

Description : The bur should be tilted lingually when preparing the occlusal surface of class II cavity on a mandibular first premolar in order to: I. Remove unsupported enamel II. Prevent encroachment on the buccal pulp horn III. Prevent ... and II B. I and III C. II and IV D. III and IV E. IV only

Last Answer : C. II and IV

Limestone addition in the blast furnace is done to flux __________ present in the raw materials. (A) SiO2 (B) Al2O3 (C) MnO2 (D) P

Description : Limestone addition in the blast furnace is done to flux __________ present in the raw materials. (A) SiO2 (B) Al2O3 (C) MnO2 (D) P

Last Answer : Limestone addition in the blast furnace is done to flux __________ present in the raw materials. (A) SiO2 (B) Al2O3 (C) MnO2 (D) P

The main constituents of glass is (A) SiO2 (B) B2O3 (C) Al2O3 (D) Cr2O3

Description : The main constituents of glass is (A) SiO2 (B) B2O3 (C) Al2O3 (D) Cr2O3

Last Answer : (A) SiO2

A patient is resistant to caries but has a periodontal disease. In this case, sucrose in diet is important because: A. Sucrose is greatly involved in plaque development B. S. mutans produces Levans frictions which are used by periodontal pathogens C. The streptococcus mutans cannot survive with a continual supply of sucrose D. Existing plaque must continue to get sucrose in order to grow

Description : A patient is resistant to caries but has a periodontal disease. In this case, sucrose in diet is important because: A. Sucrose is greatly involved in plaque development B. S. mutans produces ... with a continual supply of sucrose D. Existing plaque must continue to get sucrose in order to grow

Last Answer : A. Sucrose is greatly involved in plaque development

The characteristic feature of basal cell carcinoma is: A. Blood metastasis B. Does not erode bone C. Intensive involvement / inveterately characteristic/ D. Radio resistant

Description : The characteristic feature of basal cell carcinoma is:  A. Blood metastasis   B. Does not erode bone  C. Intensive involvement / inveterately characteristic/  D. Radio resistant 

Last Answer : C. Intensive involvement / inveterately characteristic/ 

Which is TRUE about disinfectant solutions:** A. It destroys all pathogenic micro organism including high resistant B. It reduces the number of micro organism to a non infective level C. It kills all pathogens but not spores.

Description : Which is TRUE about disinfectant solutions:** A. It destroys all pathogenic micro organism including high resistant B. It reduces the number of micro organism to a non infective level C. It kills all pathogens but not spores.

Last Answer : B. It reduces the number of micro organism to a non infective level