Unit 315 Flashcards
What type of material is alginate?
An irreversible hydrocolloid
What is zinc oxide and eugenol impression paste used for?
Permanent reline of dentures
Lower secondary impressions
What is zinc oxide and eugenol used for in restorations?
As a lining
Soothing temporary filling
Indirect pulp capping
What filling material must zinc oxide not be used under?
Composite
What is glass ionomer used for in restorations?
Class l, ll, lll and V cavitites
Temporary restorations
Fissure fillings
What is glass ionomer luting cement used for?
Permanent cementation of crowns, bridges, inlays and orthodontic bands
What is zinc polycarboxylate cement used for?
Permanent cementation of crowns, bridges, inlays and orthodontic bands
Cavity lining under restorations
Temporary fillings in deciduous teeth
What is zinc phosphate cement used for?
Permanent cementation of crowns, bridges, inlays and orthodontic bands
Temporary restorations
Cavity lining in shallow cavities
What is polyether rubber based impression material used for?
Accurate impressions for crowns, bridges, inlays and dentures
When does a cavity need filling?
When the decay has passed the ADJ
What is attrition?
Tooth loss caused by tooth on tooth contact
What is a Blacks classification l cavity?
Occlusal of a posterior tooth or the cingulum of the 1s
What is a Blacks classification ll cavity?
Occlusal plus mesial, distal or lingual on a posterior tooth
What is a Blacks classification lll cavity?
Single surface of an anterior tooth, not the incisal edge
What is a Blacks classification lV cavity?
Two surfaces of an anterior tooth, incisal plus mesial or distal
What is a Blacks classification V cavity?
A cavity on the cervical area of the tooth
What is a Blacks classification Vl cavity?
On the cusps of a posterior tooth
What revolutions per minute does an air turbine handpiece run?
500,000
What instruments can be used to remove carious dentine?
Spoon excavator or an air rotor handpiece
What revolutions per minute does an air rotor handpiece run?
40,000
What is meant by mechanical retention?
Ensuring the occlusal surface opening is smaller than the inside so the filling cannot fall out
What is meant by chemical retention?
Use of etch and bond when placing a composite filling
What are the two linings used under fillings?
Calcium hydroxide - stimulates secondary dentine
Zinc oxide and eugenol - sedative lining, not under composites
What is a plastic filling?
A filling which is soft upon insertion and sets once inserted
Why can’t amalgam fillings be polished at the appointment when they are placed?
They have a long setting time
What are millers forceps used for?
To hold articulating paper when checking occlusion
Why do we check occlusion after a restoration?
To prevent the tooth from pulpitis, strain or damage of the periodontal ligaments
What is an Arkansas stone used for?
Sharpening hand instruments - excavators, scalers etc
What are the components of amalgam?
Mercury and a metal alloy which contains 60% silver, copper, zinc and sometimes tin
What filling material are undercuts needed for?
Amalgam
What is done if there is not enough tooth structure to create uncercuts?
Dentine pins are placed
What is mandatorily needed when dealing with amalgam on a pregnant woman?
A rubber dam
What foil can be used to clear a mercury spillage?
Lead foil
What is a crocodile clip matrix clamp used for?
Celluloid matrix (clear strip)
What is a cariostatic filling material?
A filling material which prevents decay - GIC
What class of cavity is GIC best suited to?
Class V
Why is GIC usually used in deciduous teeth?
It requires minimal prep and releases fluoride
What can you add to GIC to make it stronger?
Powdered silver - reinforced glass ionomer cement
Why are temporary fillings used?
Pain relief
For permanent restorations which require more than one appointment - inlays
Insufficient time to prepare the cavity and insert the filling in one appointment
Why are cavity linings used?
To protect the pulp from pain and possible death due to thermal shock or chemical irritation by non-metallic fillings
What can be used as a temporary filling?
Zinc oxide and eugenol cement
Zinc phosphate cement
Polycarboxylate cement
Gutta percha
Advantages of zinc oxide and eugenol
Non-irritant to the pulp
Most satisfactory lining for metal fillings
Disadvantages of zinc oxide and eugenol
Not compatible with composite filings
Burning sensation if it comes into contact with the lips
Advantages of zinc phosphate cement
It sets quickly
It is very adhesive so ideal for cementing
Advantages of calcium hydroxide
promotes formation of secondary dentine
Non-irritant to the pulp, can be used as a lining
Can be used for pulp capping, pulpotomy and RCT
Disadvantages of calcium hydroxide
Too thin to use under a metal filling
Found in some mercury spillage kits
What is a thymozin probe?
Used to apply calcium hydroxide as a lining
Advantages of gutta percha
No mixing
Sets immediately
Removed easily
Disadvantages of gutta percha
Very soft
Cannot be left in a cavity for too long as it decomposes
Where is an ultrasonic scaler the most efficient at removing calculus?
Supra gingival
Where is a push/cushing scaler the most efficient at removing calculus?
Interproximal areas, supra gingival
Where is a sickle scaler the most efficient at removing calculus?
Supra gingival
Where is a gracey curette scaler the most efficient at removing calculus?
Subgingival
Where is a jacquette scaler the most efficient at removing calculus?
Supra gingival
Where is a periodontal hoe the most efficient at removing calculus?
Sub and supra gingival - root planing
Where is a universal curette the most efficient at removing calculus?
Sub and supra gingival - root planing
What is used to test tooth vitality?
Ethyl chloride - cold test
Hot GP point - hot test
Electronic pulp tester - most efficient
What is used for a direct pulp cap?
Calcium hydroxide placed directly onto the exposed pulp
What is used for an indirect pulp cap?
Calcium hydroxide placed onto the dentine that is close to the pulp chamber
What teeth is a pulpotomy carried out on?
Deciduous and newly erupted teeth
What is removed during a pulpotomy?
The coronal pulp tissue
Why can a pulpectomy not be carried out on a deciduous tooth?
Filling material in the roots cannot be absorbed
What filling material is used during a pulpotomy?
Glass ionomer, zinc oxide and eugenol or IRM
Why is a rubber dam used in a pulpectomy?
To isolate the tooth - preventing bacterial contamination of the canals and protects the patient’s airway
What are gates glidden drills used for?
Opening the coronal end of the canal
What are barbed broaches used for?
To remove the canal contents - extirpate
What are hand files and reamers used for?
To clean and shape the canal walls
What are motor files used for?
To clean and shape the canal walls
What are fingers spreaders and lateral condensers used for?
To condense GP points
What is angles classification l?
A normal bite - the upper first molars occlude with the buccal groove of the lower first molars, the incisal edge of the upper canines sit between the lower canines and first premolars
What is angles classification ll div 1?
Over jet - the mesiobuccal cusp of the upper first molars is in front of the buccal groove of the lower first molars - proclined upper incisors - horizontal
What is angles classification ll div 2?
Over bite - the mesiobuccal cusp of the upper first molars is in front of the buccal groove of the lower first molars - retroclined upper incisors - vertical
What is angles classification lll?
Negative over jet - the mesiobuccal cusp of the upper molars is behind the buccal groove of the lower first molars
What is the EDGEWISE system?
Square tubes in a fixed appliance and uses ligatures or elastic rings
What is the BEGG system?
Round tubes in a fixed appliance and uses brass pins
How do fixed appliances work?
Force is applied to the teeth through the brackets meaning more complex movements can be carried out
How are teeth moved when using a fixed appliance?
Through the action of the archwire
Through the force produced by intraoral elastics running between the brackets or from the maxilla to the mandible - teeth have to travel along the archwire preventing tipping
What is an archwire?
Piece of wire bent to the shape of the dental arch to be achieved at the end of the treatment
What are orthodontic brackets?
Attached to the teeth on the labial or buccal surface of anteriors and premolars to hold the archwire in place
What is used to cement brackets to the teeth?
GIC or composite
What are buccal tubes?
Tubes that are bonded to the tooth or welded to the orthodontic bands (usually on the first molars)
What is a ligature wire?
Tiny wires or elastic rings which hold the archwire onto the brackets
What are separating pliers used for?
To place separating rings between the teeth to create space
What are ligature cutters used for?
To trim the ligature wires
What are molar band pushers used for?
To push the molar bands into place
What are mershon band pushers used for?
To place the molar bands
What are molar band removers used for?
To manipulate or remove the molar bands
What are bracket forceps used for?
For gripping the brackets and putting them into place
What are weingart pliers used for?
To place the archwire into the buccal tubes
What are howes pliers used for?
To bend the wire and band the molars
What is an archwire tucker used for?
Applies pressure so the archwire can be pushed into the buccal tubes
What are distal end cutters used for?
To trim the excess wire poking out of the molar bracket tube
What are mathieu needle holders used for?
Allows the ligature wires to be placed and tightened
What are needle holders used for in orthodontics?
To place elastic ligatures
What are Mitchells trimmer used for in orthodontics?
To seat the molar bands and remove excess cement from around the brackets
What are bracket removers used for?
To remove the brackets at the end of the treatment
What is the headgear/extraoral traction system used for?
Preventing the posterior teeth being pulled forward during treatment
