Clinical Skills Flashcards
Describe the 520 bur
Friction grip diamond Rosehead bur 0.8 mm diameter
Describe the 544 bur
Friction grip diamond domed tip bur for occlusal cavities
3 mm length and 1 mm diameter
Describe the 554 bur
Friction grip diamond tapered bur for occlusal reduction and bevel cusps in crown prep. Flat end
Describe the 555 bur
Friction grip diamond tapered
Describe the D and Z 850/859 bur
Friction grip diamond long thin bur used to clear interproximally during crown prep
Describe the 637 bur
Friction grip diamond tapered bur for producing champher for all ceramic crown
Describe the 877 bur
Friction grip diamond tapered bur for cutting champher finish line for full Gold crown torpedo shaped
Describe the 701/702 burs
Latch grip stainless steel cross cut burs for smoothing
Describe the Rosehead burs
Latch grip stainless steel burs for cargoes removal in sizes 1,3 and 5 mm
Describe the 285/773 bur
Friction grip diamond rugby ball shaped
Used for occlusal and lingual reduction and shaping cingulum and cusps
What is the free running speed of the air turbine hand piece ?
450000-500000 rpm
What is the speed of the contra angled handpiece ?
3000-4000 rpm
What is the ideal cavo surface angle for amalgam ?
90+/- 20 degrees
What is the role of the number 18 probe in a caries restoration ?
Should not be used to diagnose caries, only to detect sound dentine on the floor of the cavity
How long should dentine by air dried for ?
3-5 seconds to prevent post op pain
What type of lining is used for amalgam cavities ?
Setting calcium hydroxide
What are the advantages of using setting calcium hydroxide as a lining material ?
Remineralises dentine
Encourages odontoblasts to lay down reparative dentine
What is the working time of the setting calcium hydroxide lining ?
6 mins
What is the purpose of a cavity varnish ?
Prevent micro leakage and secondary caries
What type of cavity varnish Is used and how is it applied ?
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
What instruments can be used to carve amalgam ?
Wards and half hollenbach
What should waste amalgam be safely stored under ?
Water
Old radiograph fixer
Potassium permanganate solution
Container with a vapour lock chemical
What lining is placed under a composite restoration ?
Light cured gic
Why should eugenol containing materials never be placed under a composite restoration ?
Plasticises the resin base
What are the advantages of placing a gic lining material in a cavity ?
Leaches fluoride
Command setting
Bonds to dentine
Similar coefficient of thermal expansion to dentine
How long should the gic lining be cured for
30 seconds with visible blue light 470 nm
What acid is used to etch enamel and dentine before placing composite ?
36% buffered phosphoric acid
How long should the enchant remain on the tooth?
Min 15 secs for enamel
Max 15 secs for dentine
What will happen if dentine is over etched ?
It will irritate the pulp causing inflammation and pain
What type of bonding resin is used for composites, how is it applied and what is its function ?
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
What does prime and bond XP contain and what products are left behind after air drying ?
Nano fillers 7 nm diameter, acetone solvent
Leaves behind penta and organic resins
What type of composite can be applied in 3 mm increments ?
Spectrum from dentsply
What method is recommended for light curing composites ?
Cure for 40 seconds from palatal, then buccal then occlusal surfaces
Start from sides first as composite shrinks towards the light source
When and how are composites finished ?
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
Which bur is used for an enamel biopsy?
520
How should enamel appear after it has been etched ?
Chalky or frosty
What is fissure sealant ?
Unfilled resin containing bis gma and tegma and 0.5 % tio2 giving it a white colour
What is the purpose of a fissure sealant ?
To contain and isolate bacteria remain giant in fissures preventing them from using carbohydrates to produce organic acids
What instrument is used to apply fissure sealant ?
Excavator
What other features of molar teeth should be considered when applying a fissure sealant ?
Buccal fissures of mandibular teeth
Palatal fissures of maxillary teeth
How long should a fissure sealant be light cured for ?
40 s
Why should frequent stops be made when removing caries with the rose head bur ?
To inspect the adj and ensure it is free from staining and firm to probing
What matrix system is used for class II composites ?
Palodent matrix system, sectional matrix with bitine ring and foil matrix
The foil Matrix is curved laterally and occluso gingivally
Describe xeno IV
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
Describe cream X mono composite
Nano hybrid composite
Heavily filled giving it strength, wear resistance and reduced polymerisation shrinkage 1% by volume
Why should light curing units be regularly checked ?
To ensure their intensity remains above 300mW/cm2
Which bur is used to cut a self retentive box ?
520
Which bur is used to cut the retention grooves in a self retentive box and where are they placed ?
Small Rosehead bur in the slow handpiece
Grooves placed in buccal and palatal walls of the cavity
How many mm is the occlusal reduction for a full gold crown ?
1mm non functional cusp
1.5 mm functional cusp
Which bur is used to perform the occlusal reduction for a full gold crown ?
554
How many mm is the cusp bevel reduction for a full gold crown ?
1 mm non functional cusp
1.5 mm functional cusp
What finish line is recommended for a full gold crown ?
135 degree champher
Which bur is used to produce the axial reduction and champher finish line for the full gold crown ?
877K
Which bur is used to clear interproximally during a full gold crown preparation ?
D and Z 850
Why is a sawing action recommended when using the D and Z 850 ?
Increases effectiveness of cutting by the small diameter bur
Increases vision
Why might a retention or location groove be placed on a full gold crown preparation ?
Is the preparation has low clinical height
Which bur should be used to cut a retention groove and where should it be located ?
554, 0.5 mm from champher line, on palatal fissure for maxillary teeth and buccal fissure for mandibular teeth
Which rotary instruments are used to smooth the edges of an ion provisional crown ?
Greenstone or black course soft flex disc
What but is used to roughen the inner surface of the temporary crown in preparation for acrylic resin?
5 mm Rosehead
Which type of acrylic resin is used to fit the temporary crown to the tooth and why ?
Trim, poly iso butyl methacrylate as it has a 14% shrinkage and is less exothermic than methyl methacrylate which has a 21% shrinkage
What is used to cement a temporary crown in place ?
Temp bond, zinc oxide eugenol cement