Test 3

Question 1

Alginate is what kind of hydrocolloid?

Answer 1

irreversible hydrocolloid.

Question 2

What are alginate impressions used for?

Answer 2

Study casts-stone.
Orthodontic casts-plaster.
Custom tray fabrication.
Legal records/forensics.
Mass disaster ID.
Mouthguard fabrication.

Question 3

What is the main ingredient in alginate?

Answer 3

Sea/marine kelp.

Question 4

What are aglinate particles comprised of?

Answer 4

Salts of alginic acid.
An activator.
A retarder.
A filler to reduce stickiness.
Flavoring.

Question 5

What are aglinate particles comprised of?

Answer 5

Salts of alginic acid.
An activator.
A retarder.
A filler to reduce stickiness.
Flavoring.

Question 6

What is the composition of alginate?

Answer 6

Potassium alginate (15%) - thickening agent.
Calcium sulfate (16%) - forms gel.
Trisodium phosphate (2%) - slows reaction.
Diatomaceous earth (60%) - adds bulk.
Zinc oxide (4%) - bulk material.
Potassium titanium fluoride (3%).

Question 7

What is the composition of alginate?

Answer 7

Potassium alginate (15%) - thickening agent.
Calcium sulfate (16%) - forms gel.
Trisodium phosphate (2%) - slows reaction.
Diatomaceous earth (60%) - adds bulk.
Zinc oxide (4%) - bulk material.
Potassium titanium fluoride (3%).

Question 8

What are considerations for alginate impressions?

Answer 8

Temp of water alters setting time.
Portions alter strength.
Humidity affects 
H2O amount and temp.
Pour within 20 mins.
Max/mand tori, deep vault, deep vestibule.

Question 9

What are considerations for alginate impressions?

Answer 9

Temp of water alters setting time.
Portions alter strength.
Humidity affects 
H2O amount and temp.
Pour within 20 mins.
Max/mand tori, deep vault, deep vestibule.

Question 10

What are the physical phases of alginate?

Answer 10

First phase = sol, material is in liquid or semi-liquid form.
Second phase = gel, material is semisolid, gelatin.

Question 11

What preprocedural rinse is best for alginate impressions?

Answer 11

Astringent is best because it:

Reduces air bubbles, mucous, food particles, bacterial load.

Question 12

What preprocedural rinse is best for alginate impressions?

Answer 12

Astringent is best because it:

Reduces air bubbles, mucous, food particles, bacterial load.

Question 13

How do you decide which tray to use?

Answer 13

Clears all tissues by 4mm, long enough to cover retromolar pads or tuberosity, do no overly depress any of the frenum, comfortable.

Question 14

How do you decide which tray to use?

Answer 14

Clears all tissues by 4mm, long enough to cover retromolar pads or tuberosity, do no overly depress any of the frenum, comfortable.

Question 15

How do you remove maxilla tray?

Answer 15

Break seal along one buccal vestibule and remove by easing out one side at a time.

Question 16

How do you remove maxilla tray?

Answer 16

Break seal along one buccal vestibule and remove by easing out one side at a time.

Question 17

How do you remove mandibular tray?

Answer 17

“snap” to break seal and ease out one side at a time.

Question 18

How do you remove mandibular tray?

Answer 18

“snap” to break seal and ease out one side at a time.

Question 19

Alginate impression considerations:

Answer 19

Premedication.
Allergy to material.
Max/mand torus.
Deep palatal vault.
Claustrophobia.
Breathing difficulties.

Question 20

Alginate impression considerations:

Answer 20

Premedication.
Allergy to material.
Max/mand torus.
Deep palatal vault.
Claustrophobia.
Breathing difficulties.

Question 21

What are ‘standards of practice’?

Answer 21

Standards are intended to guide the professional judgment and actions of dental hygienists and inspire self-reflection and continuous professional development.