Removable appliances

Question 1

Removable appliances indications

Answer 1

Tipping tooth movement
Rotation less than 90 degrees

Question 2

Classification

Answer 2

Active
(springs, screws, elastics)
Used for growth modification and tooth movement

Passive
Space maintainers, Habit breakers and Retainers

Question 3

Components of Removable appliances

Answer 3

Active components
(Springs, Bows, Retractors, Elastics, Screws)

Retentive components
(Clasps-engages undercuts)

Anchorage
(resist unwanted tooth movement)

Acrylic base plate

Question 4

Springs

Buccal-Lingual movement

Answer 4

Z spring- Anterior crossbite of single tooth
- Rotating one incisor less than 90 degrees

**T-spring **- Buccal movement of canine

**Recurved Z spring **- 2 Z springs joined at anteriro region to form one active arm used in correction of crossbite of more than 1 incisor

Question 5

Bows
Palatal-Lingual movement

Answer 5

**Hawley arch **
Reducing an overjet less than 6 mm
Retention
Less flexible than Robert’s retractor

**Robert’s retractor **
Corrects overjet over 6mm

Question 6

Mesio-distal movement

Answer 6

Finger spring
Buccal canine retractor

Question 7

Screws

Answer 7

Arch expansion
Moving one or more teethbuccaly or labially
Moving one or more teeth distally