Operative Flashcards
1
Q
Carbonate substitution_________ solubility of
hydroxyapatite
A
increases- easier to decay.
2
Q
Critical pH
* Enamel (FA)
* Enamel (CHA)
* Dentin and Cementum
A
- Enamel (FA)= 4.5
- Enamel (CHA)= 5.5
- Dentin and Cementum= 6.2-6.7
3
Q
- Root-surface lesions progresses slowly or rapidly?
A
Rapidly because no enamel
4
Q
Shapes of
* Pit and fissure lesions
* Smooth-surface lesions
A
- Pit and fissure lesions à inverted V-shape
- Smooth-surface lesions à V-shaped
5
Q
- Infected dentin
- Affected dentin
A
- Infected dentin= superficial, wet, soft, mushy, necrotic
- Affected dentin= deeper, dry, leathery, demineralized but not invaded by bacteria
6
Q
Requires _________ surface for remineralisation
A
intact
7
Q
occurs at junction of tooth and restoration indicating microleakage
A
Secondary/Recurrent
8
Q
caries that remain in a completed tooth prep
A
Residual caries
9
Q
Bacteria
* Enamel caries
* Dentinal caries
* Root caries
A
- Streptococcus mutans -enamel caries
- Lactobacillus - dentinal caries
- Actinomyces- root caries
10
Q
rapidly damages tooth structure, light-colored, soft, infectious
A
Acute or rampant caries
11
Q
brown/black, hard, caries-resistant if exposed to fluoride (dentinal lesion has sclerotic dentin)
A
Arrested caries
12
Q
Tooth needs ______% mineral loss to be detected radiographically
A
30-40%
13
Q
In transillumination Shadows can indicate
A
interproximal caries
14
Q
Marginal gap or ditching _________mm is judged carious or
caries-prone
A
> 0.5 mm
15
Q
loss of tooth structure by mechanical wear
A
Abrasion
16
Q
occlusal wear from functional contacts with
opposing natural teeth
A
Attrition
17
Q
Treatment Plan Sequencing and functions
A
- Urgent phase= acute infection, pain, swelling
- Control phase= caries, oral hygiene
- Reevaluation phase
- Definitive phase= ortho, prosth, surgery
- Maintenance phase
18
Q
Rx for incipient smooth-surface lesions
A
Remineralisation
19
Q
Rx for pits and fissures
A
sealents
20
Q
Functions
– Scalers
– Excavators
– Chisels
– Other
A
– Scalers - Calculus
– Excavators - Dentin
– Chisels - Enamel
– Other - Restoration
21
Q
Sickle scaler
Curette
A
Sickle scaler= supragingival calculus
Curette= subgingival calculus
22
Q
Rotary Instruments
* Low-speed handpiece ______ rpm
– ____ bur for safe caries removal
* Medium-speed handpiece ____rpm
* High-speed handpiece___ rpm
A
- Low-speed handpiece
– <12,000 rpm
– Large round bur for safe
caries removal - Medium-speed handpiece
– 12,000-200,000 rpm - High-speed handpiece
– >200,000 rpm
23
Q
- Carbide
– Better for ____cutting
– Produce _______ heat - Diamond
– Better for ____cutting
– Produce ________ heat
– ________ hardness
A
- Carbide
– Better for end-cutting
– Produce lower heat - Diamond
– Better for side-cutting
– Produce higher heat
– Greater hardness
24
Q
cutting= __________blades
* Finishing= ________ blades
* Fine finishing= ______blades
* Ultra fine finishing= _________blades
A
cutting= 6 blades
* Finishing= 12 blades
* Fine finishing= 18-24 blades
* Ultra fine finishing= 30-40 blades
25
* 245
– ________ mm
– ________shaped
* 330
– _________ mm
– _________shaped
– Smaller size is helpful for ______
preparations
* 169L
– shape?
* 245
– 3 mm x 0.8 mm
– Pear-shaped
* 330
– 1.5 mm x 0.8 mm
– Pear-shaped
– Smaller size is helpful for pediatric
preparations
* 169L
– Tapered fissure
26
Outline Form
initial depth of _____mm into dentin
Extend gingival floor to get ____mm clearance
* Extend facial and lingual proximal walls to get ________mm clearance
initial depth of 0.2mm into dentin
Extend gingival floor to get 0.5mm clearance
* Extend facial and lingual proximal walls to get 0.5mm clearance
27
Demineralised enamel is called
undermined enamel is called
Friable
Unsupported
28
________ enamel need to be removed because bonding agent may not be effective
Friable
29
Primary resistance features
Flat pulpal and gingival floor
rounded internal line angles
30
Primary Retention Form
Convergent
* Dovetail
31
* Convergent walls prevent _______ displacement
* Dovetail prevents _________displacement
* Convergent walls prevent occlusal displacement
* Dovetail prevents proximal displacement
32
GLUMA Composition
GLUMA
– 5% glutaraldehyde
– 35% HEMA (hydroxyethyl
methacrylate)
– Water
33
Liner include
CaOH or RMGI
34
Liner uses
* Used for direct or near pulp exposures
* Provides a barrier to protect dentin from residual reactants of
restoration and oral fluids
* Electrical insulation
* Thermal protection
* Pulpal treatment (formation of tertiary dentin)
35
Base includes
RMGI or GI cement
36
Base uses
* Used for metal restorations
and when liner is used
* Thermal protection
(especially under amalgam
and gold)
* Distributes local stress
across all underlying dentin
37
Remaining Dentin Thickness
* Amalgam
– ≥2mm
– 0.5-2mm
– <0.5mm
* Composite
– ≥0.5mm
– <0.5mm
* Gold or Ceramic
– ≥2mm
– 0.5-2mm
– <0.5mm
* Amalgam
– ≥2mm sealer
– 0.5-2mm base, sealer
– <0.5mm liner, base, sealer
* Composite
– ≥0.5mm bond
– <0.5mm liner, base, bond
* Gold or Ceramic
– ≥2mm cement
– 0.5-2mm cement (2mm thick)
– <0.5mm liner, base, cement
38
Secondary Resistance and
Retention Form
* Retentive grooves
* Beveled enamel margins
* Slots
* Pins
39
* Slots
– At least ____ mmdeep
– At least ____mm long
– ________mm inside DEJ
* Pins
– _________ pin most
common
– Usually where a _________l wall is
missing
* Slots
– At least 1mm deep
– At least 1mm long
– 0.5mm inside DEJ
* Pins
– Self-threaded pin most
common
– Usually where a vertical wall is
missing
40
Amalgam Preparation bur
Composite Preparation bur
Use a carbide bur for smooth walls
Use a coarse diamond for rough walls
41
* Collar
* Skirt
* Provide _________ R&R form
* Collar= beveled shoulder around capped cusp for bracing
* Skirt= feather-edge margin
* Provide secondary R&R form
42
Amalgam composition
50% mercury
50% metal alloy
* Silver
* Tin
* Copper
* Zinc
43
uses
* Silver
* Tin
* Copper
* Zinc
* Silver à strength
* Tin à corrosion
* Copper à strength
* Zinc à deoxidizer, but excess expansion if moisture
contamination
44
Trituration phases
* γ=
* γ1=
* γ2=
* γ= unreacted silver-tin
* γ1= strong silver-mercury matrix
* γ2= weak tin-mercury
45
* Normal mix=
* Over-trituration=
* Under-trituration=
* Normal mix= shiny, smooth
* Over-trituration= warm, wet, soft, sets too quickly
* Under-trituration= dry, dull, crumbly, sets too quickly
46
* Low-Copper- _____% Cu in the alloy
* High-Copper- ____% Cu in the alloy
* Low-Copper– <12% Cu in the alloy
* High-Copper– ≥12% Cu in the alloy
47
γ2 phase missing in high/ low copper alloy
High copper
48
less corrosion and creep is seen in high/low copper alloy
High copper
49
Which alloy particles is stronger and sets faster- Spherical/ admixed
Spherical
50
Better proximal contacts- Admixed/spherical
Admixed
51
Dental Amalgam contraindications
Very small Class VI lesions
High esthetic demands
Allergic to metals
52
* Preparation walls diverge occlusally due to
orientation of enamel rods in ________ class of amalgam
five
53
Acute mercury toxicity symptoms
– Muscle weakness (hypotonia)
– Loss of hair (alopecia)
– Weight loss/GI disorders
– Exhaustion
54
Mercury Forms
* Methylmercury= organic, most toxic
* Elemental= liquid metallic, in dental amalgam
* Mercury salts= inorganic
55
Enamel bonding has _______ MPa of shear bond strength
20+ MPa of shear bond strength
56
Reliable and predictable enamel/ dentin bonding
Enamel bonding
57
Enamel and dentin composition
organic
mineral and
water
Enamel
2% organic, 88% mineral, 10% water
Dentin
25% organic, 50% mineral 25% water
58
* Etched enamel
* Etched dentin
* Etched enamel - chalky or frosty white,
creates microporosities
* Etched dentin - exposes layer of
collagen, widens dentinal tubules
59
Primer example and it causes
HEMA, Contact dermitities
60
Etching is done with _____ and time
Etch for 15 seconds
* 30-40% phosphoric acid
61
___________ Prevents collagen collapse
Primer
62
Bond/Adhesive creates ______bond
Micro-Mechanical bond
63
Hybrid Layer is a mechanical interface blw
Mechanical interface between tooth and adhesive
64
Larger fillers= less/more strength
Higher filler content= less/more water absorption
more strength
less water absorption
65
* Composites shrink as they polymerize ___%
2-3%
66
Higher C-factor means Less/more chance for shrinkage,
microleakage, and post-operative sensitivity
more
67
Glass Ionomer composition
* Acid= polyacrylic acid
* Base= fluoroaluminosilicate glass
68
Glass Ionomer rely on________________ bond
composite resin rely on _____________ bond
chemical
MMB
69
anhydrous single pastes that contain major ingredients of both
CR and GI except for water
Compomer
70
More rapid polymerization
slower polymerization
Resin-Modified Glass Ionomers
Compomers (Polyacid-Modified Resin
Composites)
71
attracted use in orthodontics
Compomers (Polyacid-Modified Resin
Composites)
72
* Self-Cure composites _____ paste system
* Light-Cure _______ Single-paste system
TWO
Single
73
_________ nm light needed to initiate polymerization in light cure resins
468 nm
74
Light-cure ___________ photoinitiator
– Camphorquinone is
photoinitiator
75
Self cure initiator and activator?
– Benzoyl peroxide is initiator
– Tertiary amine is activator
76
Enamel can be etched for up to __________ seconds and dentin can be etched for up to _________ seconds.
Enamel can be etched for up to 20-30 seconds and dentin can be etched for up to 15-20 seconds.
77
Which type of dentin require a longer etching time
tertiary dentin is the most irregular and resilient, so it requires a longer etching time
78
Composite shade 1 represents the _______ chroma and _________ value
1 represents the least chroma and highest value (whiter)
79
Darker and more opaque shades of composite take _________ to cure.
Darker and more opaque shades of composite take longer to cure.
80
The patient has brown discoloration and chalky enamel, which is indicative of ___________I.
amelogenesis imperfecta type III.
81
The order in which teeth most commonly experience cracked tooth syndrome is:
Mandibular second molars
Mandibular first molars
Maxillary premolars
82
Hot/cold sensitivity within two weeks of an amalgam dental restoration placement is most likely due to the _____________
thermal conductivity of the amalgam
83
Root caries are often difficult to properly isolate and keep clean making it a great option for _____________.
resin-modified glass ionomers.
84
Layering resin composite over glass ionomer is commonly referred to as a ___________.
sandwich technique
85
Composite is an ideal restorative material for small Class __________ slot preparations when standard isolation is not an issue.
Class II slot preparations.
86
Abfraction is presented with ________ cervical lesions. Abrasion is presented with __________ cervical lesions.
Abfraction is presented with angular cervical lesions. Abrasion is presented with rounded cervical lesions.
87
Nanofill particles have least/ most wear resistance.
Most because Composites with the smallest-sized spherical particles exhibit the most wear resistance.
88
Senile caries, or root caries in older patients, results from ___________.
gingival recession.
89
___________ cement is the most commonly used cement for ceramic inlay and onlays.
Resin cement
90
_________ is an excellent choice of material to restore root caries as it has the ability to release fluoride.
Resin-modified glass ionomer
91
One of the disadvantages of glass ionomers is the _______ of the material, which can be irritating if placed close to the pulp.
Low pH
92
Abfraction has an _________ notch in thee cervical region, while abrasion has a __________ notch.
Angular and rounded respectively
93
Which of the following composite fillers exhibits the most wear resistance?
Nanofill
94
Occlusal caries will most often present with gray discoloration shown through the translucent enamel.
Translucency of the enamel
95
Why does dentin collapse during etching?
Exposed layer of collagen
96
which base or liner may interfere with the polymerization of a resin composite restoration?
ZOE
