Pt 2 - biomechanics

Question 1

growth modification uses what force vs tooth movement

Answer 1

orthopedic force (growth modification) and orthodontic = tooth movement

Question 2

orthopedic forces

Answer 2

heavier
over 500 gmf

orthodontic
lighter is 10-150 gmf

gmf - gram of force

Question 3

orthopedic forces application and sutures?

Answer 3

maxilla and mandible and forces of tension and pressure are on the SUTURES

Question 4

example use of restraint of growth in maxilla

Answer 4

class II - due to maxillary

Sand A angle will be larger

Question 5

augmentation of growith

Answer 5

when there is lack of growth

for example in patient class III- maxilla underdeveloping

Question 6

mandible restraint in

Answer 6

class III

Question 7

restraint or augmentation occurs in what view

Answer 7

sagital

Question 8

maxillary dental expansion

Answer 8

correct DENTAL crossbites
tipping the teeth BUCCALY
NOT orthopedic effect (single light forces)

Question 9

maxillary DENTAL expansion devices

Answer 9

TPA
- trans palatal arch
Quad helix

Question 10

maxillary PALATAL expansion

two examples?

Answer 10

correct skeletal crossbites

NO tipping
OPEN paltal suture
HEAVY orthopedic forces

Hass appliance
rapid palatal expander

Hyrax appliance
- Hygenic rapid expander

Question 11

bonded expander

Answer 11

prevents any molar extrusion

• covers all posterior teeth
• important in patients with longer faces

Question 12

Microfractures with?

Answer 12

RPE’s
- rapid palatal expanders

in early adolescence and late mixed dentition there is a complex interdigitation on palat

but after do this – more complex configuration and bony bridging

Question 13

overall for the max palatal expansion

Answer 13

suture opening that is NON PARALLEL

Question 14

type of opening in palatal expansion

Answer 14

triangular in two dimensins
- horixontal and frontal planes

occlusally opening is more pronounced anterior – (interincisal diestema)

base – occlusally - opens more on occlusal than at the nasal level

BASE ANTERIOR AND BASE OCCLUSAL

Question 15

maxilla stops growing around what age

Answer 15

10

ggrows down and forward so if want to restrain it – needs to go back and up

Question 16

describe restraint of max growth

Answer 16

excesssive max growth (Class II)

prognathic maxilla

will compress maxillary sutures

• forces oppose natural growth direction
• allow others to ‘catch up’

corrects MX/MD discrepencies

ex- HEADGEARS

Question 17

types of headgear

Answer 17

1. cervical pull – one strap around back of head
   - simplest design and produces slight extrusion of the molars
   - EXTRUDE MOLARS
2. high pull
   - USED when you need maximum vertical control
   
   • Open bite tendency
     Back and up
     - INTRUDE MOLARS
3. straight pull
   -Much more horizontal force
   Without intrusion or extrusion
   - GOES THROUGH CENTER OF ROTATION

inner bows and outer bows

Question 18

force prescription of headhears

Answer 18

500-1000 gmf
direction : slightly above occlusal plane

application - molar

12/hr day (growth hormone release)

12-18 months

Question 19

overview of augmentaion of max grwoth

Answer 19

when insufficient max growth (class III) 
- retrognathic maxilla 

TENSION ON MAX SUTURES

forces follow natural growth directions: down and forward

*very controversal / reverse headgears - “face mask”

patient compliance is extremely important factor

Question 20

petite face mask

Answer 20

rod in center
support for forehead and chin

outer bow

worn 24/7

gets hooked to elastics

Question 21

face mask - delaire

Answer 21

wireage come on the sides

Question 22

tx prior to face mask?

Answer 22

an RPE is recommended

Question 23

face mask prescription

Answer 23

force 500-1000 gmf

direction - slightly above occlusal plane

application – intraoral hooks

18-24 hours / a day

12-18 months

Question 24

sideeffects of face mask

Answer 24

proclination of upper incisors

retroclination of lower incisors

chin soft tissue irritation

Question 25

augmentation of mandibular growth overview

Answer 25

insufficient mandibular growth - class II

retrognathic mandiblel

tension on condles - glenoid fossa

forces following natural growth diretion
- advance mandible

Question 26

names of augmentation of mandibular growth appliances

Answer 26

Herbst

MARA

Twin block

Question 27

restraint of growth overview -mandible

Answer 27

excessive mandibular growth (cass III)

prognathic mandible
PRESSURE on condyles – glenoid fossa

forces oppose natural growth direction

hold md growth
very controversal

uses CHIN CUPS/ CAPS

Question 28

FORCE RX OF CHIN CUP

Answer 28

400/500 gmf

direction back and up

application - chin

24/hrs day
12-18 months

Question 29

sideeffects of chin cups

Answer 29

retroinclination L incisors
labial gingival recession

chin soft tissue irritation
TMD?

Question 30

herbst appliance

Answer 30

for mandibular augmentation

Extension arm 
	- Can be worn with or without braces 
	- Bite in advanced position 
	- Fixed 
	- Little compliance 
	- Stiff / rigidity - downfall 
Component on top and bottom

Question 31

MARA

Answer 31

for mandibular augmentaion

No hinge but interference
Full closure in an advanced position
More lateral movements allowed than ther herbst

Question 32

invisalign can be used for advancement of mandible T/F

Answer 32

true

Question 33

twin blocks

Answer 33

used for mandibular augmentation
- Removable
- Plate on maxilla and mandible
Forces a bite in forward movement