Test #3 Flashcards
1
Q
In ortho, the bond b/w the bond and the enamel is chemical or mechanical
A
mechanical
2
Q
Dr. Angle introduced what appliance, when
A
Edgewise, 1928
3
Q
Dr. Andrews introduced what appliance when
A
Modern straight wire appliance, early 1970s
4
Q
Edgewise appliances character
A
Fixed, multibanded, bonded appliances with multiple wire bends
5
Q
What was required in the wires for the Edgewise appliance
A
1st order, 2nd order, 3rd order bends
6
Q
First order do what to teeth
A
rotate
7
Q
Second order do what to teeth
A
intrusion/extrusion
8
Q
Third order do what to teeth
A
torque buccal/lingual
9
Q
Synonym for first order bends and how are they directed
A
In Out Bends, labio-lingual offsets on archwire in the horizontal plane
10
Q
Synonym for second order bends and how are they directed
A
Tipping Bends, offsets on archwire in the Vertical plane to change angulation mesio-distally
11
Q
Synonym for third order bends and how are they directed
A
Torquing Bends, placed in a rectangular archwire to change bucco-lingual or labio-lingual inclination of a tooth
12
Q
How do Straight wire appliances work
A
prescribed for individual tooth with a certain thickness base and angulation of the slot to the long axis of the tooth both in the M-D and B-L all incorporated into the bracket
13
Q
Theory of straight wire appliance
A
No need for 1st(rotating bends), 2nd (tipping bends), or 3rd (Torquing bends) order bends in the wire
14
Q
Do orthodontists still do bends w/ straight wire appliances
A
yes, do finishing bends and detailing bends b/c teeth do not have ideal anatomy
15
Q
Contemporary Fixed appliance set up
A
stainless steel bands and bracket
16
Q
Stainless steel bands usually put on which teeth
A
Molars and second premolars
17
Q
3 general types of contemporary brackets
A
Metal, Ceramic, Self-Ligating
18
Q
What can metal brackets be made of
A
Stainless Steel, titanium, gold
19
Q
Advantage of ceramic brackets
A
esthetics
20
Q
What are self ligating brackets
A
special locking mechanism built on the bracket to engage the archwire in the slot eliminating the need for ligature
21
Q
What is a ligature
A
the rubber o-ring that holds the wire in the bracket
22
Q
2 most commonly used bracket slot sizes
A
0.018 X 0.025 “ 0.022 X 0.028 “
23
Q
Band definition for the layman
A
metal that surrounds the whole tooth
24
Q
Bracket for the layman
A
little piece that sits on the front of the tooth
25
When see bonding in Ortho should think what
putting bracket on the facial of a tooth
26
What has allowed brackets to be placed as far back as the molars
direct bonding technique
27
What attachments are preferred for the anterior teeth
bonded
28
What attachments are preferred for the premolars and molars
banded or bonded
29
Which is more complicated banding or bonding & why
Banding because it requires tooth separation, fitting of the band, and cementing the band
30
Purpose of Separation
slightly loosen tight interprox contacts b/w teeth to create space to fit bands at the following appointment
31
How long separation in children
1 week
32
How long separation in adulst
2 weeks
33
Most popular separator
elastics
34
What separator to use w/ tight interproximals
brasswire and metal springs
35
Is band one size fits all and does it have
| attachments
No, they are preformed w/ prewelded attachments
36
General fitting of the band
you are stretching the stainless steel band over the tooth so that it is tight, but not so tight as to break it
37
2 most common cements used to cement the bands
Zinc phosphate Glass ionomer
38
Why are glass ionomer cements popular
elease fluoride ions to help minimize decalcification
39
how is bonding achieved in ortho
mechanical locking of adhesive to surface irregularities in enamel and to the meshed base of the orthodontic bracket
40
3 steps of bracket bonding
etch Prime
| Place resin loaded bracket and light cure
41
Etch w/ what material
37% phosphoric acid
42
Purpose of etch
create surface irregularities on enamel to enhance bonding
43
What do self-etching primers do
combine etch and prime steps
44
What are “tooth size problems “
when there is space to adjust but not so much as to need tooth removal
45
how fix tooth size problems
can go interproximally and shave off enamel (up to 3mm ?)
46
Why are brackets good for ortho “tooth size” problems
leave the interproximal surface accessible for modification
47
Which are less prone to irritate gingiva or cause white spot lesions, bands or brackets
brackets
48
If tooth will receive heavy intermittent force against attachments (e.g. max first molar w/ headgear) what is placed, band or bracket
band
49
If tooth will need both labial and lingual attachments (e.g. teeth requiring crossbite elastics) what is placed, band or bracket
band
50
If tooth has short clinical crown is band or bracket placed
band
51
If tooth surface is incompatible w/ bonding, what can be placed
band
52
Example of a tooth surface incompatible w/ bonding
restored tooth surface
53
Example of a tooth surface incompatible w/ bonding
restored tooth surface
54
3 archwire materials
Nickel titanium Beta titanium
| Stainless Steel
55
2 archwire forms
Broad
| Regular
56
3 cross sections of archwire
Round Square
| Rectangle
57
6 cross-sectional sizes of archwires
0. 014” 0.016” 0.018”
| 0. 016 X 0.016” 0.016 X 0.022” 0.016X0.025”
58
What 2 things are archwire selection based on
Treatment philosophy Stage of Treatment
59
typical nickel-titanium archwire composition
55% Nickel, 45% Titanium
60
2 properties NiTi archwir
shape memory Superelasticity
61
The superelasticity of NiTi is based on what
phase transformation from austenitic to martensitic and back
62
is thermoelasticity the same as superelasticity
No thermoelasticity is a phase change based on heating or cooling. Wire is heated, bent, and when cooled, it maintains that new bended form
63
What is Superelasticity
Phase change due to the application of stress
64
what is the stress applied to superelastic NiTi archwire
pushing the archwire into the bracket
65
What phase is a NiTi straight out of the package, unstressed, in, austenitic or martensitic
Austenitic, stiff
66
Stressing the NiTi into the bracket makes it more pliable, which is what phase, austenitic or martensitic
Martensitic, pliable
67
How do the differences in stress work on a NiTi in ortho
as the tooth moves the stress on the NiTi lesses so it goes from martensitic(pliable) to Austenitic(stiff) until it is back to its original archform
68
Wire resumes its original shape upon deflection ,low formability
Shape memory, NiTi has high shape memory
69
Low stiffness means the wire is flexible or rigid
Flexible, NiTi is Highly flexible
70
Revovery exhibited by wire upon its unloading/deactivation
Springback, NiTi has high springback
71
Maximum deformation/deflection of an orthodontic wire w/in its elastic range
Range, NiTi has high range
72
Is NiTi high or low friction and is this a disadvantage or advantage
High friction, it’s a disadvantage, can cause translation to go slower due to friction in bracket as tooth moves
73
3 disadvantages of NiTi
High Friction, Can’t be soldered, Expensive
74
NiTi is used in what phase of ortho treatment and why
Initial stage, deliver light continuous forces w/ large deflections
75
Does Beta-Titanium wire have any Nickel in it
No
76
Beta-Titanium arch wire composition
9% Titanium (Ti)
11% Molybdenium (Mo) 6% Zirconium (Zr)
4% Tin (Sn)
77
How does Beta titanium relate to NiTi and Stainless
| Steel
Stronger than NiTi but weaker than SS
78
Force level of Beta-Titanium versus for Stainless Steel for same amount of deflection
BTi has 1⁄2 force level for deflection as Stainless Steel
79
2 indications for using Beta-Titanium over Stainless Steel or NiTi
Pt has a Nickel Allergy
Pt requires force levels lower than SS but greater
than NiTi
80
What are the Springback, Range, and Friction for BetaTitanium, High or Intermediate
Intermediate
81
Can Beta-titanium be soldered or welded
Yes
82
Considered the main arch wire in most orthodontic practices
Stainless Steel
83
Stainless Steel composition
71% Iron (Fe)
18% Chromium (Cr)
8% Nickel (Ni) <0.2% Carbon ©
84
When would use Stainless Stell
finishing
85
3 reasons for Stainless Steel popularity
Good mechanical properties Corrosion Resistant
| Low cost
86
Because it is highly formable, what does that mean for Stainless Steel wire
bends will stay in the wire
87
What is the Springback and Range of Stainless Steel, low, intermediate, or high
Low
88
Initial Stage ortho main goal and wire of choice
Intraarch level and align, NiTi
89
Initial stage goal stated differently
Take care of all rotations (1st order), intrusions and extrusions (2nd order) in the arch, not focused on spaces
90
Intermediate stage focus
space closure
91
What is required for space closure in Intermediate Stage
need greater control of tooth movement for interarch correction while providing intraarch stability
92
Wire choice for intermediate stage
SS or BTi
93
Finishing stage is called
Detailing
94
Wire choice for finishing stage
SS or Bti
95
If see a chain elastic, what is that used for and what can be assumed is the wire type it covers
used for space closure(intermediate stage), so must cover a SS or BTi
96
Elastics do what
help w/ tooth movement
97
Elastic types
Class I Class II
| Class III Cross Elastics Box Elastics
98
Elastics require what for patient success
Patient cooperation
99
Elastic traction b/w teeth or groups of teeth of the same arch (e.g. during canine retraction using sliding mechanics)
Class I elastics
100
Elastics extending from the anterior aspect of the maxillary arch to the posterior aspect of the mandibular arch
Class II elastics
101
Class II elastics used for
Correct CII malocclusion Reduce overjet
| Minimize anchorage loss during max incisor retraction by taking advantage of intermax anchorage
102
If elastic goes from Max Canine to Mand Mol in Class II elastics, what will each tooth do
Max canine pulled distal and will partially extrude, Mand mol pulled mesial and partially extrude
103
Class II elastics correct class II malocclusion how
pull maxillary teeth back and mand teeth fwd
104
What is a side effect that must be managed w/ class II elastics
Extrusion
105
Elastic from Mandibular Canines to Max first molars
Class III elastics
106
Class III elastics used when
aid Class III malocclusion correction Facilitate protraction of Max Post teeth
Improve incisor relationship in edge to edge situation
107
What do max mol and mand canine do in CIII elastics
Max mol moves forward, ,mand canine moves back and both extrude
108
2 cautions for both Class II and Class III elastics
create vertical force which may open bite Move anterior teeth forward (flaring)
109
When Class II elastics are used, which anterior teeth will flare
Mandibular anterior
110
Intermaxillary elastics in various configurations used to close open bites by extruding teeth
Vertical Elastics
111
2 configurations of Vertical Elastics
Triangular or Box
112
Elastic extending from the palatal aspect of a Max tooth to the Buccal aspect of a mandibular tooth (or reverse)
crossbite elastic to correct crossbite
113
Problem w/ crossbite elastic
crosses occlusal table so pt bites on it
114
What would an elastic that goes from Right Maxillary Canine across to the Left Mandibular Canine be doing
anterior elastic to bring midline back
115
Comprehensive Orthodontic treatment typically begins when
at or after late mixed dentition
116
3 Goals of Comprehensive Ortho
Function Esthetics
| Stability
117
Treatment is hardline or compromise
Compromise of function/esthetics/stability for result that is most attainable and maintainable
118
3 functional Goals
Dental/Skeletal/ Soft Tissue
119
Function Dental Goals of Comprehensive Ortho
Class I canines
Normal Overbite/Overjet (2mm/2mm) Canine or Group function guidance
No crowding or spacing
120
Function Soft tissue Goals of Comprehensive Ortho
Lips close w/ minimum strain Balanced soft tissue
