midterm Flashcards
1
Q
concerns about amalgam
A
esthetics
weakening of tooth from removed from structure
recurrent caries
sense
2
Q
comp advs
A
asethetics
bonding
more conserv
less exspensive
reduced merc
3
Q
composite dis
A
shrink
durability
chip
more skill
dry
time and expense
4
Q
articulator 4 uses
A
diagnosis
treatment planning
communicate with patients/patient education
fabrication of prostheses/resorations
5
Q
semi-adjustable articulators:
a.
-condyle in LOWER member
-condylar inclination in the upper member
b.
-condyle on UPPER member
-condylar inclination on the lower membrane
A
a. acron
b. non acron
6
Q
what kind of articulator do we use
A
Hanau Articulator
Acron (semi-adjustable)
7
Q
allow only opening and closing movements. type of articulator
A
hinge or non adjustable
8
Q
the facebow is used to
A
orient the cast in the same relationship to the opening axis of the articulator in 3 planes
9
Q
what plane do we use for our facebow
A
arbitrary
10
Q
locates the true transverse horizontal axis of rotation
A
kinematic plane
11
Q
locates the axis by using anatomical landmarks (uses average measurements to approx. locate axis of rotation)
A
arbitrary plane
12
Q
what
-goes through both condyles
-around the axis pure rotational movement of mand. occurs
-8 mm under soft tissue in front of tragus
A
terminal hinge axis
13
Q
point 10mm anterior to center of spherical insert in external auditory meatus and 7mm below frankfort horizontal plane
A
bergstrom point
14
Q
what is known as the 3rd point of reference on facebow
A
anterior reference point
-needs to be reproducible and repeatable
15
Q
when to use facebow?
A
- cusp teeth are present
- interocclusal records are made at an increased OVD
- OVD subject to change and alteration in occlusal surfaces are necessary
16
Q
what bones are involved in chewing
A
maxilla
mandible
temporal bone
17
Q
components with processes of maxilla
A
body
processes:
-zygomatic
-frontal
-alveolar
-palatine
18
Q
largest and strongest bone of skill with components:
A
mandible
body and ramus
19
Q
articulates with cranium
-medial and lateral poles
length 15-20mm
ant-post 8-10mm
A
condyle
20
Q
squamous portion articulates mand condyle
A
temporal bone
21
Q
muscles of mastication
A
temporalis
lateral and medial pterygoid
masseter
22
Q
elevates mand and powerful muscle that provides force for chewing. has superficial and deep head
A
masseter
23
Q
masseter
superficial head=
deep head=
A
superficial= aids in protrusion
deep=stabilizes
24
Q
masseter blood supply and nerve supply
A
blood= branch of max artery
nerve= masseter nerve of mand division of CNV
25
temporalis 3 divisions with actions:
anterior= mand is raised vertically
middle= elevates and retrudes mand
posterior= aids in retrusion of mand
26
blood and nerve supply of temporalis
blood= muscular branch of max artery
nerve= deep temporal nerve of mand division of CNV
27
lateral (external) ptyergoid 2 heads (almost 2 separate muscles)
superior lateral and inferior lateral
28
what muscle? (depresses/protudes)
a. causes condyles to be pulled down the articular eminence and mandible is protuded:
b. causes mediotrusive movement (down, foward, medially):
inferior lateral pterygoid actions.
a. bilateral contraction
b. unilateral contraction
29
superior lateral pterygoid action. (elevates)
inactive when:
active when:
-inactive during mand opening
-active only with elevator muscles (closing of mand) and during closure against resistance (eating) aka POWER STROKE
30
lateraly pterygoid blood and nerve supply
blood-muscular branch of max artery
nerve- masseteric or buccal nerve of man division of CNV
31
1. elevates mandible
2. protrudes mandible
3. unilateral contraction
results in mediotrusion
medial (internal) pterygoid
32
what muscle causes condyles to be pulled down articular eminences and depress mandible?
lateral pterygoid
33
masseter sling
masseter and medial pterygoid
34
suprahyoids as a group
geniohyoid
mylohyoid
digastric
stylohyoid
35
elevates hyoid bone and depress mand when hyoid bone is fixed
suprahyoids
36
what nerve innervates the TMJ
trigeminal
37
what muscle protrudes mandible?
lateral pterygoids
38
DEPRESSION of mandible.
what muscles cause contractions:
causes relaxation:
contraction:
-inferior lateral pterygoids
-digastric
relaxation:
-masseter
-medial pterygoids
-temporalis
(opposite of elevation of mand)
39
ELEVATION of mandible.
contraction:
relaxation:
contraction:
-masseter
-medial pterygoid
-temporalis
-superior lateral pterygoid
relax:
-inferior lateral pterygoid
-digastric
(opposite of depression but add superior lat. ptery.)
40
right lateral mand movement
contraction
relaxation
contraction:
-left inferior lateral pteryg
relax:
-right inferior lateral pteryg
-slight relaxation of elevators
41
left lateral mand movement
contraction
relaxation
contraction:
-right inferior lateral pteryg
relax:
-left inferior lateral pterg
-slight relax of elevators
42
mand protrusion
contraction
inferior lateral pterygoids mainly assisted by masseters and medial pterygoids
43
retrusion of mand
contraction
temporalis
44
what are indications for crown?
-caries
-trauma
-endodontically treated posterior teeth
-previous restorations
-where axial and occlusal contours require substantial correction
-extensive coronal destruction
45
chamfer margin on gold crown?
0.5mm
46
functional cusp reduction on gold crown?
non-functional?
(mand functional cusp-buccal)
1.5mm also for central groove
(mand non-functional cusp-lingual)
1.0mm
47
where do you make retention groove
on functional cusp side (buccal)
48
functional cusp bevel measurements
1.5mm tapers to 1.0mm
49
what is the sequence of crown prep?
1. occlusal reduction/functional cusp bevel
2. axial reduction
3. proximal reduction
4. secondary retentive features
5. margination
50
dimension of reduction for facial and lingual:
0.5-1mm
51
axial reduction:
.5-1
52
ability to replicate the intraoral surface details
accuracy
53
ability to retain its absolute dimensional size over time
dimensional stability
54
ability to resist tearing in thin sections
tear resistance
55
factors responsible for success of impression material
1
2
3
easy to manipulate, comfortable for patient, and inexpensive
56
sodium
potassium
triethanolamine alginate
active ingredients for irreversible hydrocolloid impression material
57
potassium alginate
calcium sulfate (reactor)
diatomaceous earth
few ingredients of alginate
(for some reason i had these three highlighted)
58
influence alginate setting time by altering
temp of water
59
mixing alignate time
45secs to 1 min
60
thickness of alginate impression between tray and tissues should be at least
3mm
61
alginate hydrocolloid materials are strain-rate dependent. tear strength is ______ when the impression is removed with a snap
increased
62
working time is:
a. The amount of time from when you mix a substance to
when it hardens
b. The time to use a workable mix, one that maintains a uniform consistency to perform one or more tasks
c. Aand B
b
63
The time to use a workable mix, one that maintains a uniform consistency to perform one or more tasks
working time
64
The amount of time from when you mix a substance to
when it hardens
setting time
65
proposes when mixed with water, plater enters into colloidal state thru SOL-GEL mech
colloidal theory
66
rehydrated plaster particles join together thru hydrogen bonding to the sulfate groups to form the set material
hydration theory
67
based on dissolution of plaster and instant recrystallization of gypsum followed by interlocking of crystals to form set solid
dissolution precipitation theory
68
chemical added decreases setting time:
increases setting time:
decrease: accelerator
increase: retarder
69
stone used to process denture casts because strong and denture easy to remove after processing
(yellow)
type III stone
70
if patient needs minimal restorations, this is the position the restorations are made in
MI
71
when condyle is in most super anterior position in the articular fossae, resting against posterior slopes of articular eminences with articular discs interposed
CR
72
joint where mandible articulates with base of cranium
TMJ
73
more than 3 bones
-condyle, temporal, articular disc
compound joint
74
allows more than one type of movement
complex joint
75
joint implies hinging movement=
implies gliding=
implies both=
hinging: ginglymoid
gliding= arthrodial
both=ginglymoarthrodial
76
contacts with synovial fluid
synovial joint
77
made of dense fibrous connective tissue
non-innervarted and avascular
articular disc
78
articular disc shape
concave=
concavo-convex=
concave= inferior part
concavo-convex=superior part
79
articular disc is divided into 3 SAGITTAL sections:
anterior zone
middle or intermediate zone
posterior
which is thinnest and which is thickest
thinnest= middle
thickest=posterior
post>ant>middle
80
articular surface of the condyle functions on the ______ of the disc
intermediate (middle) zone
81
articular disc divided into 2 FRONTAL sections:
1
2
which is thicker?
medial and lateral
thicker medially
82
-most superficial layer of articular surfaces (condyle and fossa)
-unlike other synovial joints, this layer is made of dense fibrous connective tissue rather than hyaline cartilage; less susceptible to aging and better ability to repair
articular zone
83
contains undifferentiated mesenchymal cells and is responsible for proliferation of articular cartilage in response to loads
proliferative zone
84
3D network of collagen offering resistance to lateral and compressive forces
fibrocartilaginous zone
85
made up of chrondocytes and chrondoblasts
calcified zone
86
synovial joint.
all areas of joint not involved in articulation (internal surfaces of cavities) are covered with
specialized endothelial cells that form synovial lining
-produce synovial fluid
87
movement of fluid from one area of joint cavity to another; prevents friction
boundary librication
88
articular surfaces absorb some of the fluid, increased absorption during function, metabolic exchange
weeping lubrication
89
disc innervation and blood suplly
mand branch of CNV and superfcial temporal artery-
90
-attaches articular disc to tympanic plate
-connective tissue
-lot of elastic fibers
-stretches as joint is moved forward
superior retrodiscal lamina
(posterior attachments of disc)
91
-collagenous attachment (not elastic)
-attaches posterior of disc to the posterior margin of articular surface of condyle
inferior retrodiscal lamina
(posterior attachment of disc)
92
what happens in inferior joint compartment?
superior joint compartment?
inferior= rotation
superior=translation
93
-collateral/discal ligaments
-capsular ligament
-temporalmandibular ligament
functional ligaments
94
-sphenomandibular ligament
-stylomandibular ligament
accessory ligaments
95
ligament that surrounds joint like curtain
capsular ligament/joint capsule
96
-thickening of capsular ligament on lateral aspect
-two parts: outer oblique (prevent over-rotation) and inner horizontal (PAIN)
temporalmandibular ligament
97
(movement)
occurs in inferior joint compartment
rotational movement
98
(movement)
occurs in superior joint compartment
translation movement
99
4 anatomic determinants of movement
right and left tmj
teeth/occlusion
neuromusculature
100
process of turning about an axis.
occurs when mouth opens and closes around fixed point within condyles
rotation
101
rotation occurs for the first ______mm of opening
20-25mm
102
3 planes rotation movement may occur
sagittal plane around horizontal axis
horizontal plane around vertical
frontal plane around sagittal
103
-this movement is clinically identifiable and recordable
-only rotational movement that can be isolated clinically
-**this movement occurs only when mandible is in CR
rotation in sagittal plane around horizontal axis
104
every point in an object(mandible) simultaneously moving in the same direction with same velocity
translation
105
depression of mand (beyond 25mm) and protrusion
translation
106
during lateral movement
condyle on side towards which mandible moves (rotating condyle)
working side condyle
107
this is the condyle on side opposite to which mandible moves (orbiting condyle)
non-working side
108
angle at which condyle moves away from horizontal reference plane
condylar angle
109
a. condyle moves forward and downwards
b. condyles move down posterior slope of articular eminence
c. can use this movement to record condylar guidance angle
during protrusion
110
angle formed by the intersection of protrusive and non-working condylar paths as viewed in sagittal plane
5-10 degrees
-medial wall steeper than posterior slope of articular eminence
Fischer's angle
111
during a lateral movement, this is the condyle on the side towards which mandible moves
working
112
in left lateral movement, working condyle would be
left
113
angle at which NWS condyle moves medially away from sagittal reference plane as viewed in horizontal plane during lateral movement (lateral movement)
bennett angle
114
T/F
in most people, MIP coincides with CR
false
115
condyle-disc seembly is anterior and inferior and/or medial or lateral
maximal intercuspal position or max intercuspation
116
habitual postural of mandible when patient is resting comfortably in upright position and condyles are in neutral unstrained position in glenoid fossae
teeth arent touching
-muscles aren't completely relaxed
PP
postural position (PRP)
117
used to determine OVD in edentulous patients or patients with severely won dentition
postural position (PRP)
118
outer range of movement is reproducible and called
border movements
119
combination of border movements in all 3 planes
envelop of motion
3 planes are:
1. sagittal
2. horizontal
3. frontal
120
average distance between CR and MIP
1.25mm
121
what determines tooth position
muscles
genetics
habits
122
anterior-posterior curvature of occlusal plane. concave in mandible, convex in maxilla
curve of spee
(curve of wilson is side to side from frontal view)
123
