Twin Block

Question 1

Twin block is which gp myofunctional appl?

Answer 1

GP 3

Question 2

Twin block is active or passive?

Answer 2

Active… Tooth borne….

Question 3

Twin block… Composition??

Answer 3

Consists of upper n lower bite blocks… Inclined plane r angled at 70°….

Question 4

Abt vertical clearance while bite registration??

Answer 4

1. There should be enough vertical clearance between cusps of upper n lower Pm to accommodate the twin block..
2. Vertical activation must open the bite beyond the freeway space to ensure the pt CAN NOT drop the mand in rest position…

Question 5

Clasp used for retention in twin block?

Answer 5

Delta clasp…

Question 6

Delta clasp??

Answer 6

The main differ6between delta n Adams clasp us that ….in delta is the Retentive loops which r shaped in closed triangle… Whereas in Adam’s clasp it’s open v shaped loop….

Question 7

Adv of delta clasp over Adam’s clasp?

Answer 7

1. More retention
2. Less meatal fatigue
3. Minimised named for adjustment

Question 8

Angulations of twin block vary between?

Answer 8

45 to 70°

90° —— on the earliest, the bite blocks articulate at 90° ————+ PT has to consciously put effort to occlude in forward direction…

45° —— this is the 1st modification…

70° —— Now steeper to make sure the horizontal growth of mand… (Forward growth)

Question 9

The two blocks in twin block r inclined at??

Answer 9

65° (It’s 70° actually)

Choose 65 over 75 if both these given…

Question 10

Pterygoid response or altered muscle balance seen in?

Answer 10

Twin block … (Pain felt)

Retrodiscal tissue stuff….

Question 11

Reactivation of twin block to increase the forward position of mand is achieved by adding cold cure acrylic to increase the anterior incline….?

Answer 11

Upper twin block MESIALLY… (Not lower distally)

If overjet is greater than 10 mm… The mand is stepped forward in 2 stages…
The 1st step is abt 7 to 8 mm n the 2nd activation is such that … The upper n lower incisors come in edge to edge relation…

If arch correction is not achieved even now… An additional activation is needed…

Phased activation is indicated in ADULT pts when muscles n ligaments r less responsive to sudden, large displacement…

Question 12

Twin block .. principle?

Answer 12

They basically change the OCCLUSAL INCLINED PLANE!! By functional mandibular displacement… (By bringing the MANDIBLE FORWARD!!!!)

Twin block is worn FULL TIME…

Question 13

Pt cooperation with twin block is good or bad?? N why??

Answer 13

Gd… Because…

1. Bite block allows greater degree of movement in transverse n sagittal direction. .
2. Allows normal oral function..
3. Results seen in 3 to 4 months!!

Question 14

Which removable appl can be used in class 2 class 3?

Answer 14

Twin block..

Std twin block - in class 2…

In class 3… It brings the mand backwards..

Question 15

Which can be considered as a FIXED twin block?

Answer 15

Maxillary anterior Repositioning appliance… As it is CEMENTED… considered a fixed type..

Question 16

Which of the following can be considered to be a fixed twin block appliance?

Answer 16

Maxillary Anterior Repositioning Appliance… (MARA)

It is CEMENTED…. So considered to be fixed….
Is similar to TWIN Block in that it keeps the mandible forward all the time….

Question 17

The comfort zone for the intergingival height for an adult pt is?

Answer 17

Ans - 17 to 19 mm…

During the Twin block an easy method to establish correct vertical dimension is COMFORT ZONE… that is the intergingival height… Which is measured from the Gingival margin of the upper Incisor to the gingival margin of the lower Incisor…

Patients whose intergingival height varies significantly from the comfort zone are at a greater risk of developing temporomandibular disorders….

Seen in patients with deep bite whose intergingival distance is reduced and in patients with an anterior open bite intergingival height is increased…