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
What is the retentive component of a removable orthodontic appliance?
The Adams crib - these are clasps
Anterior retention may be needed through an incisor clasp or labial bow
What are adams pliers used for?
To adjust the wires on removable appliances
What are adams spring forming pliers used for?
To adjust or bend the springs
What are mauns wire cutters used for?
To cut the wires - they are heavy duty
What is a straight handpiece used for in orthodontics?
To trim the base plate of a removable appliance
Advantages of a removable appliance
Can be carried out by a general practitioner
Takes less chairside time
Less expensive
Easier to clean
Disadvantages of a removable appliance
Do not offer precise control
Types of corrections are limited
Difficult to close extraction gaps
Treatment takes longer
How do functional appliances work?
Use the force of the muscles in the face and mouth to create movement
What angles classifications does a functional appliance correct?
Class ll div l and some class lll
What is the acquired (salivary) pellicle?
The layer on top of the enamel. It is where bacteria colonate
The types of bacteria in plaque
Day 1 - gram positive streptococci
Day 3 - gram negative cocci, bacilli and filamentous
Day 8 - streptococci veridans, fusiform bacilli, spirochetes and vibrios
What is an intrapulpal injection?
Injecting anaesthetic into the pulp
What is an intraoesous injection?
Injecting anaesthetic into the bone
What is an intraligamentary injection?
Injection into the ligaments (down the side of the tooth)
What is an infiltration?
Injection local to the site of the treatment
What is an anaesthetic block?
Anaesthetizing all lower teeth by injecting into the inferior dental nerve
What is the general length and gauge of a short needle?
20mm and 30 gauge
What is the general length and gauge of a long needle?
32mm and 27 gauge
What acid causes tooth decay?
Lactic acid
What is the critical PH?
5.5
What is the normal PH?
7
How long does bacilli take to build up?
3-4 days
How long does treponema take to build up?
A week
What is the inflammatory process of the gingiva?
Toxins from bacteria irritate the gingiva causing inflammation
What teeth is a tofflemire matrix used for?
Premolars
What teeth is a siqveland matrix band used for?
Molars and premolars
What are cervical matrixes for?
Cervical cavities (class V) - commonly buccal abrasions
What is the term for the when the bone fuses with the implant?
Osseointegration
Causative factors of caries
High NME sugar diet
Poor oral hygiene
Stagnation areas
What is dental plaque biofilm made of?
Saliva, oral debris and normal mouth bacteria
What are the three main areas of caries prevention?
Increase the tooth resistance to acid attacks
Modify the diet
Control the build up of plaque
What component of tooth paste strengthens the enamel against acid attacks?
Fluoride
What component of tooth paste acts as a plaque suppressant?
Triclosan
What component of sensitive toothpastes helps with sensitivity?
Arginine
NovaMin
Stannous fluoride
What is the least effective method of interdental cleaning?
Woodsticks
What substance in mouthwash helps with sensitivity?
Potassium nitrate
What substance in mouthwash helps with soft tissue inflammation?
Hydrogen peroxide
What substance in mouthwash helps patients who suffer with periodontal infections?
Chlorhexidine
What is a detergent food?
A food to be eaten at the end of a meal which is raw and hard food to stimulate salivary flow and requires chewing so brushes off excess food
When will chewing gum have effectively cleansed the teeth?
After around 10 minutes - when the gum loses it’s flavour
How much fluoride is in fluoride varnish?
22,600ppm
What is enamel fluorosis?
When a child ingests excessive fluoride
What does enamel fluorosis look like?
Mottled white areas in the enamel of newly erupted teeth
How does local anaesthetic work?
Blocks the electrical transmutations from the source of the pain to the brain
What components of local anaesthetic are classed as drugs?
The anaesthetic and the vasoconstrictor
What waste should used locals anaesthetic cartridges go in?
Infectious hazardous waste
What type of waste would out of date anaesthetic cartridges be put in?
Non hazardous waste
What is the most common vasoconstrictor in local anaesthetic?
Adrenaline
What medical conditions should adrenaline free local anaesthetics be used for?
Hypertension, cardiac disease and hyperthyroidism
What group of people should avoid adrenaline containing anaesthetics?
Elderly patients
What drugs could contra indicate anaesthetic?
HRT and thyroxin
What are aspirating anaesthetic syringes used for?
Avoid injecting a blood vessel
What types of injections are given for the extraction of an upper tooth?
Buccal and palatal infiltration
Sometimes a posterior superior dental nerve block for 2nd and 3rd molars
What types of injections are given for the extraction of a lower tooth?
ID block or mental nerve block with lingual infiltration for premolars and anteriors
ID block and long buccal nerve infiltration for molars
What doesn’t need to be anaesthetised for a restoration?
Palatal/lingual gingiva
Where should sharps policies be present?
Wherever sharps are being used - ideally next to each sharps bin
What is paraesthesia?
Pins and needles feeling when anaesthetic is wearing off
What are the two main types of anxiety control?
General anaesthetic and conscious sedation
Which type of anxiety control retains the patients protective reflexes against blockage of the airway
Conscious sedation
What is an enamel chisel used for?
Removing any unsupported enamel from the cavity edges
What is a gingival margin trimmer used for?
To trim the margin of the cavity to ensure no unsupported enamel remains
What is the dove tail technique?
Technique in ensuring that the inside of the cavity is larger than the opening so the filling does not fall out of the medial and distal surfaces
What is microleakage?
Minute amounts of fluid and debris are able to leak through gaps between the filling and the walls and contaminate the pulp
Why are linings placed in cavities in relation to microleakage?
To seal the dentine tubules off to prevent microleakage
What is the best method of moisture control?
Rubber dam
What burs are used with air turbine handpieces?
Diamond and tungsten carbide
Advantages of air turbine handpieces
Ease and speed of cutting
Disadvantage of air turbine handpieces
Little tactile sensation
What burs are used with a slow handpiece?
Stainless steel or tungsten carbide
What is a round bur used for?
Gaining access to the cavity and at a low speed for removing caries
What is a pear bur used for?
For shaping and smoothing cavities
What is a fissure bur used for?
For shaping and outlining the cavity
What should hand instruments be sharpened on?
Arkansas stone
What is the biggest advantage of zinc phosphate?
You are able to control its setting time
What is the main disadvantage of zinc phosphate?
Cannot be used a liner in deep fillings as it is an irritant to the pulp
What is the most adhesive cement?
Zinc polycarboxylate
Main disadvantage of calcium hydroxide?
Can only be used as a sub lining under amalgam as is too thin
What is an advantage of calcium hydroxide in terms of PH?
It is an alkaline which counteracts the acidity of zinc phosphate and also kills off any residual bacteria present in deep cavities
What is the most widely used permanent filling material for a posterior tooth in the UK?
Amalgam
What patients should amalgam not be used on?
Children under 15
Pregnant women
Breast feeding women
What chemicals are used to a larger amalgam spillage?
Calcium hydroxide and flowers of sulphur
What is an advantage of composite regarding setting times?
As it is a light cure system, the dentist has more control over the setting time
How deep can the curing light penetrate?
2mm
What does vitamin A help with?
Saliva production
What does vitamin C help with?
Gum health
What can a vitamin D deficiency affect?
Gum disease, caries rate and inflammation of the gingiva
What is haemostasis?
Stopped bleeding - first stage of healing
How can you avoid an oroantral fistula?
Avoid too much pressure
Section the roots
Refer to a specialist
Why might a liner be placed under glass ionomer restoration
To protect the pulp from acrylic acid
How can a tooth with reversible pulpitis be saved
With a normal filling
What is the success rate of a pulpectomy?
85%
If the roots have what degree of curvature they should be referred to a specialist for endodontic treatment?
15 degrees
Why are handpieces more favourable than reamers?
Because they can be used for any canal shape rather than reamers which are just used for circular canals
what colour are non-latex rubber dam sheets
Purple and blue
What colour are latex rubber dam sheets
Green
If a rubber dam cannot be used what must be attached to the hand instruments
a parachute chain
What does it mean if at the second visit the root canal is not dry
The apical infection is still present
What teeth can a pulpotomy be carried out on?
Deciduous teeth and teeth which erupted up to 3 years ago
What fillings should be used for an open apex root
A spiral root canal filler with a non-setting calcium hydroxide paste
During an apicectomy, what instrument is used to scrape out the infected soft tissue from the bone cavity
Mitchell’s trimmer or surgical curette
What is pyrexia
A raised body temperature
What is a chromogenic material?
A material which changes colour depending on the mixing and setting stage
What gloves should be worn when mixing addition silicone impression material
Vinyl as some types of rubber PPE gloves can affect the mixing and setting times
How long does the silicon impression take to set
Four minutes
What should impressions be disinfected in
10% sodium hypochlorite
How long should impressions be disinfected for
Up to 10 minutes
What is also known as boxed trays
Dentate trays
How much of the natural tooth does a crown replace
At least 3/4
How much of the overall two dimensions is reduced for a metallic or ceramic crown
1 mm
How much of the overall tooth dimension is reduced for a bonded crown
1.5mm
What is a fixed fixed bridge
Retaining teeth are involve to either side of the missing tooth as one solid design
What is a fixed movable bridge
Where a joint is incorporated in the bridge to allow some degree of flexibility
What is a simple cantilever bridge
A bridge where the retaining teeth are to one side of the pontic only
What is a spring cantilever bridge
Where the retaining teeth are to one side but several teeth away from the pontic
What is an adhesive bridge
Whether retaining teeth undergo minimal tooth preparation and retention is provided by metal wings
Why are fixed fixed bridges not used so frequently now
As they are inflexible so can cause damage to the retaining teeth
How is occlusion checked on a bridge
Shimstock
When can adhesive bridge be used posteriorly
 ideally if the patient has no opposing teeth or the opposing teeth are on a denture
What are the oral hygiene instructions for crowns and bridges
Regular toothbrushing with a fluoride toothpaste
Regular interdental cleaning careful use of floss to not dislodge the crown
Attend the dentist regularly
A sensible diet
What can be carried out for edentulous patients to improve retention of a denture
Alveoplasty or Alveolectomy
What are the advantages of chrome cobalt dentures
they are better for patients with deep overbites onto their palate
They are thinner and stronger Cover minimal tissue making them more comfortable

What material is used for the final impressions of chrome cobalt dentures
Elastomer in a special tray
What denture has an extra stage
Chrome cobalt - extra try in stage
What teeth are immediate dentures usually made for
Anterior teeth
What material are immediate dentures made from
Acrylic as chrome cobalt cannot be adjusted
When are tissue conditioners used
As a soft lining when the soft tissues beneath the denture are sore
As a functional impression which sets over a few hours and records the soft tissues
What happens when you bite into a soft tissue conditioner
 The occlusal force is dissipated therefore causing less pain
What material are obturator impressions made from
Elastomer
advantage of keeping a retained root
It holds the alveolar bone in place and stops it receding
What do retained roots have to be for an overdenture
Root filled
What type of patient can have a functional appliance
When the mandible is still growing but after the premolars have erupted
What is interproximal reduction
Careful trimming and adjustment of teeth as treatment with removable aligners progresses
What is the term for inflammation occurring in the gingival soft tissue surrounding an implant
Peri implantitis
What is bacteraemia?
Bacteria from an infection entering the bloodstream causing the patient to become unwell
What is a Couplands chisel used for
For splitting multirooted teeth
What is the technique used of handing sterile bad instruments to the dentist
The no touch technique
What is ankylosed?
When a deciduous tooth has failed to exfoliate because the root has become cemented to the alveolar bone
What bur is often used in tooth sectioning
A diamond bur, usually a crown preparation bur for its length
Why does the mucoperiosteal flap have to have a large base
To ensure adequate blood supply for healing
How long does reattachment take of the mucoperiosteal flap
Around seven days
Vertical impaction
The tooth is up right but impacted into the Ramus
Horizontal impaction
The tooth is lying on its side 
Mesio angular impaction
The tooth is tilted forwards into the second molar
Disto angular impaction
The tooth is tilted backwards into the Ramus
Why are impacted teeth left in situ 
Extensive bone removal can weaken the mandible
The nerves can be damaged
Trismus can occur temporarily 
How long after the extraction does bleeding stop
Five minutes
In which jaw can failure of a blood clot formation occur?
Mandible
