Ortho 3Rd Year

Front 1

The best time to fix class II with an FA (functional appliance) is what ages?

Back 1

9-11
-mature enough to follow instuctions yet plenty of time left for growth

Front 2

What are the 2 strong evidences for how FAs work?

Back 2

1. glenoid fossa remodelling
2. dentoalveolar changes?

Front 3

What are the 2 weak evidences for how FAs work

Back 3

1. maxillary growth restriction (headgear type)
2.maxillary molar distalization

Front 4

3 potential advantages of the FA (functional appliance)?

Back 4

-enlarge transverse width of arches to relieve crowding
-reduce dysfunctional habits and time with braces after
-no Fixed appliance issues (gingival proliferation, extractions etc)

Front 5

What are the 3 categories of FA?

Back 5

1. passive tooth borne
2. tissue borne
3. active tooth borne

Front 6

in terms of the position of the mandible and incisors, what criteria indicate an FA?

Back 6

-a retruded mandible
-proclined maxillary incisors
-retroinclined mandibular incisors

Front 7

Besides a non compliant patient and crowding , what are contraindications to an FA?

Back 7

class II skeletal by max prognathism
class III skeletal by mand prog
vertically directed grower
labial tipping of lower incisors

Front 8

Is the activator tooth or tissue borne?

Back 8

tooth borne
-advances mandibular jaw

Front 9

What was the bionator designed to do?

Back 9

modify tongue behavior and bring it into correct position to correct class III and class II
-encourage normal development of the arch

Front 10

Is patient compliance required for Herbst?

Back 10

no bc its entirely cemented onto teeth
-the most dentoalveolar changes when compared to other FA

Front 11

what is the only tissue borne appliance?

Back 11

Frankel appliance
-serves as a template against which the craniofacial muscles function
-the vestibular shields and anterior labial pads remove muscle forces in the buccal and labial areas that restrict skeletal growth

Front 12

What are the purpose of upper lip pads in the Frankel III?

Back 12

eliminate the restrictive pressure of the lip on the underdeveloped maxilla.
-stimulate bone growth

Front 13

What patients benefit from Face mask therapy?

Back 13

Midface insufficience
Mandibular prognathism
Maxillary hypoplasia
clefts
tongue problems

Front 14

What is a twin block?

Back 14

passive tooth borne appliance
-two parts which carry inclined planes that meet and posture the mandible forward on closing
-max has attachment for head gear
-max expansion needed in class II cases
*effective at OB and OJ reduction

Front 15

can the klearway appliance be adjusted to allow molar eruption and width expansion?

Back 15

NO, but the twin block can

Front 16

3 reasons for relapse from FA include?

Back 16

1. inadequate time for skeletal eruption
2. continuued growth in the genetically determined pattern
3. dental relapse of tipping movements.

Front 17

If you wanted to open the palate with expansion screws, how many turns ?

Back 17

.25 increments so 4 turns.

Front 18

3 things Removable appliances can be used for?

Back 18

growth modification
minor tooth movement
retention

Front 19

3 advantages of removable app?

Back 19

-reduced chair time bc fabricated in lab
-removed as needed by patient (social , hygiene)
-growth guidance potential

Front 20

`disadvantages of removable app?

Back 20

-patient compliance required
-tooth movement primarily limited to tipping teeth

Front 21

3 tooth borne functional appliances?

Back 21

-activator
-bionator
-twin block

Front 22

How do functional appliances produce their affects?

Back 22

-they alter the position of the mandible

Front 23

the 3 purposes of a functional appliance?

Back 23

1)modify the pattern of jaw growth
2)alter the direction of tooth eruption
3)correct the jaw discrepancies

Front 24

functional appliances are typically followed by?

Back 24

fixed appliances to detail the position of teeth and finalize the occlusion

Front 25

tooth borne, opens the bits and class II correction (advances mandible)

Back 25

activator

Front 26

a modification of the original activator. Tooth borne passive appliance , class II correction

Back 26

bionator

Front 27

tooth borne passive appliance , class II correction. Two pieces (max and mand), acrylic ramps posture jaw forward on closure.

Back 27

Twin block

Front 28

labial tipped lower incisors

Back 28

contraindication to twin block!

Front 29

which functional appliance can correct class II or III?

Back 29

Frankel!! only tissue borne

Front 30

How does a removable appliance contact the tooth?

Back 30

aim for center of resistance. "pure translation"-->every part of tooth (crown/root) moves at same rate
-we apply force where we can. removable appliances have limited control.
-we are a pool cue instead of tongs trying to direct a ball

Front 31

the limitations of tooth movement with removable appliances

Back 31

-contact the tooth surface at one point (difficult to create a couple)
-can achieve tipping movements as bodily movements not attainable.

Front 32

-expansion appliances typical movement is?

Back 32

transverse and labial

Front 33

-aligners typical movement is?

Back 33

repositioning individual teeth

Front 34

the 3 major components of a removable appliance?

Back 34

1. retentive components (clasps to hold in place)
2. Framework and baseplate (acrylic)
3. tooth moving elements (springs or screws)

Front 35

6 kinds of clasps for the retentive component?

Back 35

1. Ball
2. Adams
3. Occlusal
4.Arrow
5. circumferential
6.molar tube

Front 36

what is the most common design for the wire springs of a removable appliance?

Back 36

Z spring
-push teeth forward when px bites down

Front 37

How does the spring aligner (modified Hawley) work?

Back 37

the lab makes it in the position the teeth should be

Front 38

an essex retainer not covering the 7s is a disaster waiting to happen why?

Back 38

over eruption of 7s. Pain and challenging to fix-->full braces!
-must have occlusal coverage over all teeth

Front 39

For the max anterior teeth and the mand anterior teeth plus the 4s, what is your aim for bracket tip?

Back 39

the long axis of the bracket must be lined up with the vertical long axis of the tooth
-pan and palpation can help

Front 40

For the max premolars and the mandibular 5s, what is the bracket tip?

Back 40

the bracket slot must be parallel to a line connecting mesial and distal marginal ridges

Front 41

which teeth have a measurement of 4 when placing brackets?

Back 41

max centrals, max 5s
mand incisors and premolars

Front 42

which teeth have 3.5?

Back 42

max lateral incisors
mand/max 6s

Front 43

which teeth have 4.5?

Back 43

mand canines and max 4s

Front 44

what is the canine measurement for bracket placement?

Back 44

5

Front 45

the first wires we use are ?

Back 45

circular and have no effect on torque

Front 46

the second wires we use are?

Back 46

rectangular and do have effect on torque

Front 47

the bow configuration for occipital headgear

Back 47

shorter outer bow with outer bow 10 degrees higher than inner bow

Front 48

what is the only bow configuration that will cause undesireable distal crown tip with occipital headgear?

Back 48

a long and low outer bow

Front 49

the bow configuration for cervical headgear

Back 49

long outer bowwith outer bow 10 degrees higher than inner bow

Front 50

what other bow configurations will cause undesireable distal crown tip with cervical headgear?

Back 50

ALL OTHER

Front 51

so what is the difference between cervical and occipital bow configurations?

Back 51

cervical requires a long outer bow and occipital requires a short outer bow. You can remember this by "it's a long way to the neck"-cervical

Front 52

bow configuration for combination headgear?

Back 52

only shorter outer bows. OUter bow ten degrees higher than inner bow

Front 53

what ortho emergencies can wait until the next appointment?

Back 53

-loose bracket
-loose band
-broken arch wire
-irritation

Front 54

what are emergencies that need to be scheduled ASAP?

Back 54

-Loose RME, TPA LLHA
-several loose brackets and bent archwire
-severe discomfort
-loose band with pain

Front 55

when is the best time to make class II corrections in children?

Back 55

9-11 yrs

Front 56

there is strong evidence for how Functional appliances and how they work by:

Back 56

glenoid fossa remodelling
dentoalveolar changes

Front 57

in terms of indications for a functional appliance, the mandible should be _______, the maxillary incisors should be ______, the mandibular incisors should be ________

Back 57

-mandible should be retruded
-maxillary incisors proclined
-mandibular incisors retroclined

Front 58

mesiolabioversion

Back 58

the crown of the tooth is abnormally far forward in the arch and it abnormally far out labially

Front 59

rotated mesiolabially

Back 59

the mesial surface of the tooth is turned labially

Front 60

dental crossbite

Back 60

-tooth bodily positioned lingually or facially
-incorrect long axis inclinations

Front 61

osseous skeletal crossbit

Back 61

- due to a mismatch in the position or size of the faciolingual perimeter of the basal bone that supports the alveoli

Front 62

what are functional crossbites usually caused by?

Back 62

occlusal interferences

Front 63

transversion

Back 63

wrong order in the arch

Front 64

Andrews 6 keys to normal occlusion

Back 64

1. class I molar relationship
2. correct tip
3. correct torque
4. no rotations
5. tight contacts
6. shallow curve of spee

Front 65

torque

Back 65

describes tooth angulation faciolinugally

Front 66

which teeth have positive torque (labial)

Back 66

the max incisors, all the rest have negative torque

Front 67

what does the anterior positive torque influence?

Back 67

- bite depth
-esthetics
-anterior spacing
-posterior intercuspation

Front 68

when the torque on the max anterior is negative, what happens to the posterior max teeth?

Back 68

mesial movement to fill in gaps and improper occlusion

Front 69

a reverse curve of spee will result in ______ room for the upper teeth

Back 69

excessive room

Front 70

primary dentition: when do the central and lateral incisors erupt?

Back 70

6-9 months

Front 71

primary dentition: when do the first molars and canines erupt?

Back 71

12-18 months

Front 72

primary dentition: when do the second molars erupt?

Back 72

20 -24 months

Front 73

the most common eruption sequence for permanent dentition

Back 73

612 4537 8

Front 74

class I molar relationship can develop in 2 ways from deciduous to mixed dentition:

Back 74

1. mesial step terminal plane
2. straight flush terminal plane then mesial drift of the lower 6s

Front 75

combined leeway on max vs mand?

Back 75

max. =.9
mand=1.7 (greater mesial drift!)

Front 76

mandibular incisors erupt _____ to the primary teeth

Back 76

erupt lingual

Front 77

the eruption of the mandibular lateral incisor causes _______ of the primate space

Back 77

closure bc it pushes the primary canine distally and labially

Front 78

should u move lateral max incisors before canines are close to eruption?

Back 78

no! the lateral incisor roots guide the canine eruption

Front 79

what is the tooth most suceptible to impaction/malposition in the mand arch?

Back 79

second premolar bc it is the last tooth to be "fitted in"

Front 80

if leeway space is small, what should be considered if the second molar erupts before the second premolar?

Back 80

space maintainer so there is no mesial drift of the 6
*obtain a pan tho bc these are often congenitally absent

Front 81

what is the most favorable sequence of max canine and premolar eruption?

Back 81

first premolar, second premolar, canine

Front 82

which second molar should erupt first, max or mand>

Back 82

the lower second molar should erupt first to prevent over eruption of the upper second molar.

Front 83

the mandibular arch intercanine distance _____ after eruption of canines.

Back 83

decreases

Front 84

what analysis if aided by cephalometrics in orthodontic diagnosis and treatment planning?

Back 84

1. The A-P relationship of max to mand (skeletal class)
2. the A-P relationship of the arches (dental class)
3. The A-P relationship of the arches to basal bone and soft tissues

Front 85

glabella

Back 85

the most anterior point of the frontal bone

Front 86

nasion

Back 86

junction of frontal and nasal bones
(notch)

Front 87

sella turcica

Back 87

pituitary gland

Front 88

anterior nasal spine

Back 88

spinous process of maxilla forming most anterior projection of the floor of the nasal cavity

Front 89

posterior nasal spine

Back 89

the most posterior projection of the junction of the palatine bones in the midlines of the floor of the nasal cavity

Front 90

pognion

Back 90

the most anterior point on the symphysis of the mandible

Front 91

gnathion

Back 91

deepest point on chin where anterior curvature becomes concurrant with inferior border of mandible

Front 92

menton

Back 92

most inferior point of mandible

Front 93

porion

Back 93

most superior point of external auditory meatus

Front 94

gonion

Back 94

the most inferior and posterior point at the angle formed by the ramus and body of mandible

Front 95

facial plane

Back 95

connects nasion and pognion

Front 96

SN plane

Back 96

connects sella and nasion

Front 97

Frankfort horizontal plane

Back 97

joins orbitale and porion

Front 98

does arch length increase from mixed to permanent dentition>

Back 98

no , it decreases due to mesial drift of 6s
females =3.4 mm decrease
males= 4.5 mm decrease

Front 99

total leeway space of mandible and maxilla?

Back 99

max- 1.8 mm total
mand= 3.4 mm total

Front 100

in mixed dentition describe obtaining arch length required?

Back 100

measure widths of 21 and 12, then read down to 75% prob level . To this figure , add your 21 and 12 dimensions

Front 101

how would u preform arch length analysis?

Back 101

measure the arch length available from mesial of 6 to 6.
-leeway: measure the widths of canine and premolars and subtract the predicted permanent widths
-now take the arch length available and subtract the leeway space.

Front 102

why do we subtract the leeway space?

Back 102

it will be lost unless special measure to preserve it

Front 103

how do u find the arch length deficiency or excess?

Back 103

take the arch length and subtract arch length required (1+2+pred 345)

Front 104

Mixed dentition analysis where you take 1/2 the sum of the widths of the mand incisors +10.5 and do the same for max but + 11mm

Back 104

Tanaka johnston method

Front 105

>4mm crowding

Back 105

extraction

Front 106

a very early loss of primary tooth will have a ______ effect on the eruption of permanent successo

Back 106

retarding

Front 107

most common cause of premature exfoliation of the primary canine

Back 107

inadequate arch length. the erupting laterals resorb the primary canines roots

Front 108

the necessity of space maintenance _________ as we move posteriorly.

Back 108

increases

Front 109

does the bolton analysis have any direct connection with arch length analysis?

Back 109

no , it simply assesses compatibility of tooth sizes, without reference to adequacy of arch length

Front 110

the lower face growth approximate

Back 110

general bodily growth curves

Front 111

cortical drift

Back 111

the bone will move toward the direction of progressive growth. they add new tissue on one side and remove tissue on the other side

Front 112

an example of secondary displacement

Back 112

marked displacement and movement of the maxillary complex anteriorly and inferiorly due to increase in size of the bones that compose the middle cranial fossa

Front 113

what are the growth sites in the base of the skull

Back 113

1. sphenoccipital synchondrosis
2. intersphenoidal synchondrosis
3. spheno ethmoidal synchondrosis

Front 114

what is the most significant suture?

Back 114

-spheno-occipital

Front 115

when does growth cease for this suture?

Back 115

12-15 years

Front 116

when does this suture close?

Back 116

20 yrs

Front 117

when is the major growth contribution for the spheno ethmoidal suture?

Back 117

6-7 yrs of age

Front 118

when does the intersphenoidal suture activity stop?

Back 118

birht

Front 119

when does the mandibular symphysis close?

Back 119

1-2 yrs

Front 120

what kind of growth at condyle?

Back 120

endochondral

Front 121

posterior border of ramus growth

Back 121

intramembranous

Front 122

for boys maximum condylar change occurs ?

Back 122

concurrantly with sutural and skeletal height peaks

Front 123

what about girls?

Back 123

about 1 1/2 yrs earlier than boys

Front 124

cleft palate

Back 124

failure of secondary palate closure
not race related (unlike cleft lip)
7-8 weeks gestation
multifactorial

Front 125

hemifacial microsomia-what is the cause?

Back 125

failure of the brachial arches I and II in morphogenesis

Front 126

what weeks of gestation?

Back 126

3-4 weeks

Front 127

mobius sequence

Back 127

mask like facies with VI and VII cranial nerve palsy

Front 128

Robin sequence

Back 128

the mandible stops developing and therefore prevents decent of the tongue between the palatal shelves , resulting in u shaped cleft palate

Front 129

down syndrome

Back 129

max hypoplasia
macroglossia

Front 130

hypohidrotic ectodermal dysplasia

Back 130

lack of sweating , abberations in hair growth and dentition

Front 131

most common for ectopic eruption

Back 131

mand laterals

Front 132

most common tooth to ankylose

Back 132

primary molars and mandible

Front 133

do u treat a diastema at age 6 caused by the frena?

Back 133

only if the space is >3mm, otherwise wait until permanent canines are in

Front 134

" rule of thumb" for habit breaking

Back 134

should be broken once the permanent incisors start to erupt

Front 135

characteristics of a mouth breather

Back 135

-long narrow face
-protruding teeth
-lips apart at rest
-steep mandibular plane
-retruded mandible
-over erupted molars
-anterior open bite
-maxillary constriction
-excessive overjet

Front 136

can orthodontists affect basal bone?

Back 136

no, it is alveolar bone that orthodontists remodel. In addition it is only existing alveolar bone that can be remodelled, u cannot get new alveolar bone laid down.

Front 137

tipping

Back 137

alteration in long axis of tooth that primarily affects the crown and not the root apex position

Front 138

where is the Center of rotation?

Back 138

in the apical third of the root

Front 139

what can a removeable appliance reliably do?

Back 139

TIP

Front 140

bodily movement

Back 140

translational movement
no center of rotation bc no rotation

Front 141

intrusion

Back 141

tooth moved vertically into its tooth socket

Front 142

extrusion

Back 142

tooth moved vertically out of socket

Front 143

torquing

Back 143

movement of root apex in facial or lingual direction w minimal but clinically significant movement of the crown.
-centre of rotation is facial to the crown

Front 144

uprighting

Back 144

root paralleling.
-predominantly movement of root apex mesial or distal
-center of rotation is in the center of the bracket

Front 145

the mechanism by which teeth move orthodontically

Back 145

bony remodelling

Front 146

what is the principal of anchorage?

Back 146

for every action there is and equal and opposite reaction . It is fundamental that in ortho these reactive forces are prevented from causing unwanted tooth movement

Front 147

extra oral anchorage

Back 147

-guarantees dissipation of reactive forces to an area where they cannot possibly cause unwanted tooth movement.
*head gear!

Front 148

the prevalence of buccal crossbite in deciduous dentition

Back 148

8-16%
*same for mixed!

Front 149

When can hidden crossbites occur?

Back 149

-when an crossbite appears only after correction of dental compensation
-in a class II when the skeletal A-P relationship is corrected, a wider part of the mandible moves into a more narrow part of the maxilla . So posture the the mandible forward to check the transverse relationship.

Front 150

cleft cases are always_____ deficiency?

Back 150

maxillary deficiency
-paranasal hollowing
-they need surgery

Front 151

how do dental anterior crossbites happen?

Back 151

-insufficient arch length
-over retention of primary teeth
-ectopic development of bud
-on or two teeth

Front 152

what about skeletal anterior crossbites?

Back 152

skeletal class III
entire anterior segment
no amount of manipulation can fix it

Front 153

explain a functional anterior crossbite

Back 153

"pseudo class III"
-manipulation may bring incisors edge to edge or positive overjet, however, the patient is obliged to posture forward upon closure due to one or two tipped teeth in normal function
-can have dental and skeletal componenet

Front 154

what important concept does this highlight?

Back 154

the need to determine CO-CR discrepancies in every patient

Front 155

why correct crossbites?

Back 155

chipping and wearing of teeth, perio problems, esthetics

Front 156

dental/functional treatment for anterior crossbites

Back 156

RA with springs (tipping)
FA with springs (tipping)
FEA (torque/upright/bodily translation)
bite plane or comp occlusal buildups to "jump the bite"

Front 157

skeletal anterior crossbite treatment

Back 157

-face mask for maxillary deficiency
-posterior bite plane to jump bite
-FEA
surgery in non growers

Front 158

treatment for dental posterior crossbites

Back 158

-RA with springs
-RA with midline jackscrew
-FA
-cross arch elastics
-occlusal adjustment/extraction of primary canines

Front 159

skeletal posterior crossbites treatment

Back 159

-RME
-superscrew
-W-arch
-quad helix

Front 160

what are the advantages of a W-arch/quad helix in treatment of a skeletal posterior crossbite

Back 160

-practitioner controls amount of expansion
-individual dental movement
-easy adjustment for patient

Front 161

disadvantages of quad helix/W-arch?

Back 161

-increased chair time
-increased dental tipping compared to RPE
-arms can be distorted and broken

Front 162

why does it take 3 sessions at 1 week intervals to remove an appliance at UBC clinic?

Back 162

-remove bands, archwire and take impressions for retainer
-debond brackets, prophy, impressions for models, insert retainers
-retainer check and adjustment

Front 163

the 5 stages of ortho treatment

Back 163

1. leveling and aligning
2. vertical correction
3. A-P correction
4. Finishing
5. retention

Front 164

the main cause of short term relapse

Back 164

gingival tissues

Front 165

arch expansion and proclination of anterior teeth more than 2mm or any expansion across canines.

Back 165

unstable arch form

Front 166

intra arch relapse contribution

Back 166

-gingival/perio /soft tissues

Front 167

inter arch relapse contribution

Back 167

continued growth

Front 168

can retainers be passive in design?

Back 168

yes

Front 169

3 types of removable retainers

Back 169

1. Hawley Type
2. Vacuform
3. Positioner

Front 170

what retainer is great for holding deep bite , posterior cross bites and transverse corrections. There are several variations in its design

Back 170

Hawley retainer

Front 171

what are the designs

Back 171

wrap around Hawley
additional springs/clasps
acrylic on labial bow

Front 172

what is best for holding spaces closed and non compliance?

Back 172

Bonded retainer

Front 173

why have an ortho screening before age 7?

Back 173

-the posterior occlusion is established when first molars erupt
-incisors have begun to erupt
-significant treatment benefits from early screen

Front 174

indications for Headgear

Back 174

-prominent maxilla
-steep mandibular plane angle

Front 175

SNA

Back 175

A-P position of the maxilla relative to the cranial base

Front 176

SNB

Back 176

A-P position of the mandible relative to the cranial base

Front 177

ANB

Back 177

skeletal jaw discrepancy of maxillary to mandibular apical bases

Front 178

U1-SN

Back 178

relationship between maxillary dentition relative to the maxilla.

Front 179

U1-NA

Back 179

position of the maxillary dentition relative to maxilla

Front 180

L1-MP
L1-NB

Back 180

MP-inclination of lower incisors
NB-position of lower incisors

Front 181

MP-SN

Back 181

growth direction

Front 182

Holdaway H-angle

Back 182

soft tissue profile

Front 183

SNA is greater than the mean

Back 183

maxillary protrusion

*less would be mandibular retrusion

Front 184

SNB is less than the mean

Back 184

mandibular retrusion

*greater than would be mandibular prognathism

Front 185

ANB greater than the mean

Back 185

skeletal class II

Front 186

Sn-Pg greater than the mean

Back 186

mandibular prognathism

Front 187

U1-L1(interincisal angle) greater than the mean

Back 187

retroinclination

Front 188

U1 - SN greater than the mean

Back 188

proclination

Front 189

U1-NA greater than the mean

Back 189

proinclination

Front 190

L1-MP greater than the mean

Back 190

proinclination

Front 191

L1-NB (position)

Back 191

incisal protrusion

Front 192

MP-SN greater than the mean

Back 192

vertical growth

Front 193

Pg-NB greater than the mean

Back 193

prominent chin button

Front 194

H-Angle greater

Back 194

convex profile