Clinical Skills

Question 1

Describe the 520 bur

Answer 1

Friction grip diamond Rosehead bur 0.8 mm diameter

Question 2

Describe the 544 bur

Answer 2

Friction grip diamond domed tip bur for occlusal cavities

3 mm length and 1 mm diameter

Question 3

Describe the 554 bur

Answer 3

Friction grip diamond tapered bur for occlusal reduction and bevel cusps in crown prep. Flat end

Question 4

Describe the 555 bur

Answer 4

Friction grip diamond tapered

Question 5

Describe the D and Z 850/859 bur

Answer 5

Friction grip diamond long thin bur used to clear interproximally during crown prep

Question 6

Describe the 637 bur

Answer 6

Friction grip diamond tapered bur for producing champher for all ceramic crown

Question 7

Describe the 877 bur

Answer 7

Friction grip diamond tapered bur for cutting champher finish line for full Gold crown torpedo shaped

Question 8

Describe the 701/702 burs

Answer 8

Latch grip stainless steel cross cut burs for smoothing

Question 9

Describe the Rosehead burs

Answer 9

Latch grip stainless steel burs for cargoes removal in sizes 1,3 and 5 mm

Question 10

Describe the 285/773 bur

Answer 10

Friction grip diamond rugby ball shaped

Used for occlusal and lingual reduction and shaping cingulum and cusps

Question 11

What is the free running speed of the air turbine hand piece ?

Answer 11

450000-500000 rpm

Question 12

What is the speed of the contra angled handpiece ?

Answer 12

3000-4000 rpm

Question 13

What is the ideal cavo surface angle for amalgam ?

Answer 13

90+/- 20 degrees

Question 14

What is the role of the number 18 probe in a caries restoration ?

Answer 14

Should not be used to diagnose caries, only to detect sound dentine on the floor of the cavity

Question 15

How long should dentine by air dried for ?

Answer 15

3-5 seconds to prevent post op pain

Question 16

What type of lining is used for amalgam cavities ?

Answer 16

Setting calcium hydroxide

Question 17

What are the advantages of using setting calcium hydroxide as a lining material ?

Answer 17

Remineralises dentine

Encourages odontoblasts to lay down reparative dentine

Question 18

What is the working time of the setting calcium hydroxide lining ?

Answer 18

6 mins

Question 19

What is the purpose of a cavity varnish ?

Answer 19

Prevent micro leakage and secondary caries

Question 20

What type of cavity varnish Is used and how is it applied ?

Answer 20

Copal resin dissolved in an ether solvent

3 coats are added with air drying between each coat as circular pits appear when the solvent evaporates

Question 21

What instruments can be used to carve amalgam ?

Answer 21

Wards and half hollenbach

Question 22

What should waste amalgam be safely stored under ?

Answer 22

Water
Old radiograph fixer
Potassium permanganate solution
Container with a vapour lock chemical

Question 23

What lining is placed under a composite restoration ?

Answer 23

Light cured gic

Question 24

Why should eugenol containing materials never be placed under a composite restoration ?

Answer 24

Plasticises the resin base

Question 25

What are the advantages of placing a gic lining material in a cavity ?

Answer 25

Leaches fluoride Command setting Bonds to dentine Similar coefficient of thermal expansion to dentine

Question 26

How long should the gic lining be cured for

Answer 26

30 seconds with visible blue light 470 nm

Question 27

What acid is used to etch enamel and dentine before placing composite ?

Answer 27

36% buffered phosphoric acid

Question 28

How long should the enchant remain on the tooth?

Answer 28

Min 15 secs for enamel | Max 15 secs for dentine

Question 29

What will happen if dentine is over etched ?

Answer 29

It will irritate the pulp causing inflammation and pain

Question 30

What type of bonding resin is used for composites, how is it applied and what is its function ?

Answer 30

Prime and bond XP Applied and left undisturbed for 30 seconds Air dried and then light cured for 10 seconds The bond penetrates the tubules and triple helix of collagen exposed by the etching process of the inter tubular and peri tubular dentine

Question 31

What does prime and bond XP contain and what products are left behind after air drying ?

Answer 31

Nano fillers 7 nm diameter, acetone solvent | Leaves behind penta and organic resins

Question 32

What type of composite can be applied in 3 mm increments ?

Answer 32

Spectrum from dentsply

Question 33

What method is recommended for light curing composites ?

Answer 33

Cure for 40 seconds from palatal, then buccal then occlusal surfaces Start from sides first as composite shrinks towards the light source

Question 34

When and how are composites finished ?

Answer 34

Can be finished immediately, green and white stones used to recreate anatomy, silicone impregnated tips used to polish, prisma fine then extra fine used at end

Question 35

Which bur is used for an enamel biopsy?

Answer 35

520

Question 36

How should enamel appear after it has been etched ?

Answer 36

Chalky or frosty

Question 37

What is fissure sealant ?

Answer 37

Unfilled resin containing bis gma and tegma and 0.5 % tio2 giving it a white colour

Question 38

What is the purpose of a fissure sealant ?

Answer 38

To contain and isolate bacteria remain giant in fissures preventing them from using carbohydrates to produce organic acids

Question 39

What instrument is used to apply fissure sealant ?

Answer 39

Excavator

Question 40

What other features of molar teeth should be considered when applying a fissure sealant ?

Answer 40

Buccal fissures of mandibular teeth | Palatal fissures of maxillary teeth

Question 41

How long should a fissure sealant be light cured for ?

Answer 41

40 s

Question 42

Why should frequent stops be made when removing caries with the rose head bur ?

Answer 42

To inspect the adj and ensure it is free from staining and firm to probing

Question 43

What matrix system is used for class II composites ?

Answer 43

Palodent matrix system, sectional matrix with bitine ring and foil matrix The foil Matrix is curved laterally and occluso gingivally

Question 44

Describe xeno IV

Answer 44

Self etching and bonding primer Able to penetrate the micro mechanical pores it creates in enamel and hybrid zone of dentine The acid primer is applied to tooth and left undisturbed for 30 s After 30 s the acidic primer will have buffered and neutralised but the time is long enough for the resin groups on the acid to enter the micro mechanical pores Xeno contains butanol as a solvent giving it a longer working time than bonding agents with acetone Light cured for 10 s

Question 45

Describe cream X mono composite

Answer 45

Nano hybrid composite | Heavily filled giving it strength, wear resistance and reduced polymerisation shrinkage 1% by volume

Question 46

Why should light curing units be regularly checked ?

Answer 46

To ensure their intensity remains above 300mW/cm2

Question 47

Which bur is used to cut a self retentive box ?

Answer 47

520

Question 48

Which bur is used to cut the retention grooves in a self retentive box and where are they placed ?

Answer 48

Small Rosehead bur in the slow handpiece | Grooves placed in buccal and palatal walls of the cavity

Question 49

How many mm is the occlusal reduction for a full gold crown ?

Answer 49

1mm non functional cusp | 1.5 mm functional cusp

Question 50

Which bur is used to perform the occlusal reduction for a full gold crown ?

Answer 50

554

Question 51

How many mm is the cusp bevel reduction for a full gold crown ?

Answer 51

1 mm non functional cusp | 1.5 mm functional cusp

Question 52

What finish line is recommended for a full gold crown ?

Answer 52

135 degree champher

Question 53

Which bur is used to produce the axial reduction and champher finish line for the full gold crown ?

Answer 53

877K

Question 54

Which bur is used to clear interproximally during a full gold crown preparation ?

Answer 54

D and Z 850

Question 55

Why is a sawing action recommended when using the D and Z 850 ?

Answer 55

Increases effectiveness of cutting by the small diameter bur Increases vision

Question 56

Why might a retention or location groove be placed on a full gold crown preparation ?

Answer 56

Is the preparation has low clinical height

Question 57

Which bur should be used to cut a retention groove and where should it be located ?

Answer 57

554, 0.5 mm from champher line, on palatal fissure for maxillary teeth and buccal fissure for mandibular teeth

Question 58

Which rotary instruments are used to smooth the edges of an ion provisional crown ?

Answer 58

Greenstone or black course soft flex disc

Question 59

What but is used to roughen the inner surface of the temporary crown in preparation for acrylic resin?

Answer 59

5 mm Rosehead

Question 60

Which type of acrylic resin is used to fit the temporary crown to the tooth and why ?

Answer 60

Trim, poly iso butyl methacrylate as it has a 14% shrinkage and is less exothermic than methyl methacrylate which has a 21% shrinkage

Question 61

What is used to cement a temporary crown in place ?

Answer 61

Temp bond, zinc oxide eugenol cement