farshad mohebby

Resto Sememinar I

Mohebbi,Farshad

DMD 4-BB

1.Secondary dentin may be formed:

►  A.after direct pulp capping is done

►  B.as a result of trauma during cavity preparation

►  C.in response to function

►  D.in response to caries

(A) its because the material used in direct pulp capping can make the pulp produce secondary dentin.

2. The most important consideration for pulp protection in restorative technique is:

►  A.an adequate protective base

►  B.complete removal of caries

►  C.thickness of remaining dentin

►  D.proper sealing of the remaining dentin

(D) Seealing is very important in pulp protection because if its not sealed the microbacterias can leak to the pulp floor.

3. Preperation of class 1 cavity for the reception of amalgam , direct filling gold and gold inlay have in common:

►  A.divergence of the buccal and lingual walls occlusally

►  B.divergence of the mesial and distal walls occlusally

►  C.convergence of the buccal and lingual walls occlusally

►  D.undercutting the mesial and distal walls

(B) Divergance of the mesial and distal wall is common for all of these  preparations.

4. When utilizing self-threading , friction-locked pins for the retention of amalgam , it is generally agreed that the pin should extend about equally into the dentin and the alloy. The recommended pin depth is :

►  A.1mm

►  B.2mm

►  C.3mm

►  D.4mm

►  E.4.5mm

(B) 2mm is enough to achive the great retention and fit in the restoration.

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5. Aside from initial penetration into the cavity, the round bur is:

►  A.used for extension

►  B.used for excavation

►  C.used for creation of undercuts

►  D.a and b

►  E.b and c

(B)the round bur is indicated for excavation because of its shape and access to the caries.

6. The recommended condensation pressure of amalgam for proper adaptation into the tooth preparation is ___per increment of amalgam.

►  A.2-4 lbs

►  B.3-5 lbs

►  C.4-6 lbs

►  D.5-7 lbs

►  E.6-8 lbs

(E) If its less like 3 lbs it will not fill all the prepared areas and undercuts.

 7 - The ideal tooth reduction for indirect inlay/onlay per cusp is:

►  A. 1-1.5 mm

►  B.1.5-2 mm

►  C.2-2.5 mm

►  D.2.5-3 mm

►  E.any of the above

(B) It’s the amount that wouldn’t expose or irritate the pulp and its reduced enough to sit the inlay/onlay.

8. The best surface finish in a composite restoration is created by:

►  A.the mylar matrix with no additional finish

►  B.the 12-fluted finishing bur

►  C.the silica grit disks

►  D.the lubricated cuttle disks

►  E.finishing strips

(A) The myler matrix is designed for smooth surface and its smooth itself.

      9. It provides a means of artistic expression that feeds on creativity and imagination       which improve self-image and enhance self-esteem of patients.

►  A.asthetics

►  B.tooth preparation

►  C.restoration

►  D.none of those mentioned

(A) When we talk about artistic expression its all about aesthetics and looks not the tooth preparation.

10. This damage to the tooth results from trauma

►  A.caries

►  B.attrition

►  C.abrasion

►  D.abfraction

►  E.fractures

(D) Abfraction is caused by trauma to the tooth.

11. Condensation time for amalgam should be finished within 4 minutes after trituration because:

►  A.the final sett takes place within 5 minutes

►  B.beyond that time, the residual mercury retention is markedly increased

►  C.the excess will be more easily removed

►  D.studies indicate that this is the most efficient working time

►  E.all of these

(B) The amalgam will be retentive and will be attached to the teeth after 4 minutes after filling.

12. The following represent cutting instruments:
l.excavator,chisel,bur
ll.drill,reamer,lancet,scaler
lll.file,disk,strip
lV.point,disk,strip

►  a.l & ll

►  B.ll & lll

►  C.l,ll & lll

►  D.ll,lll & lV

►  E.l,ll,lll & lV

(A) Only first two numbers are cutting, the rest include polishing instruments.

13. Marginal leakage related to temperature change occurs to the greatest extent with:

►  A.amalgam alloy

►  B.unfilled resin

►  C.composite resin

►  D.direct filling gold

►  E.all of the choices

(C) Composite resin is the most temperature extensive restorative material among these.

14. The direction of mesial and distal walls of a class V amalgam cavity preparation is determined by the:

►  A.necessity for retention

►  B.size of the carious lesion

►  C.direction of the enamel rods

►  D.gingivoaxial and occlusaoaxial line angles

(B) Its because all the carious lesions must be removed, so if the lesions are extended the preparation will be extended too.

15.Wearing of tooth by exigency material incising masticating and grinding functions.

A. Attrition

B.erosion

C. abration

D. abfraction

(C) abraton is the only mechanical wearing of tooth which caused by incising masticating and grinding functions, others are chemical.

16.This type of material require macromechanical retention.

A. GI

B. Composite

C. Amalgam

D. Both

E. NOTA

(C) Amalgam is the material that dose not need acid eching and its retention gained by undercuts on the preaperation.

17. minimally invasive method for  removal of advanced dentin caries during this method target is outer layer:

A. rotary cutting instrument preperation

B. pulsed erbium laser preparation

C. chemo mechanical caries removal

D. air abfraction abration

E. none

(C) chemo mechanical caries removal is the technique that removes all the carious dentin chemically, therefore it woun't remove any amount of un carious dentin.

18. fracture of class II Dental amalgam restoration at junction between the occlusal and peroximal is result of inadequate?

A. retention form

B. resistance form

C. convenience form

D. extension for prevention

E. A and B

(B) if the resistance form in a class two amalgam restoration is decreased fracture will happen.

19.the principle reason for a cavosurface bevel of inlay preparation:

A. remove undermine enamel

B. improve marginal adaptation

C. decreased marginal protectiob

D. increase resistance and retention foarm

E. distribute none of occlusal load to inlay

B) in inlay preparation cavosurface bevel is a must to be able to adapt and fit the filling material.)

20.Which of the ff solution used to etch enamel when using acid etch technique w/composite resi:

A. 50% alicophosphoric acid

B. 75% phosphoric acid in water

C. 37% phosphoric acid in water

D. 25% hydrofluride acid in buffer

(C) for composite resin restoration the maximum attachment of filling material and the preaperation is obtained by 37% phosphoric acid in water which would not cause damage to the enamel/dentin.