Physics and Chemistry of Light Curing

Question 1

What is the most common photo-initiator? (lighter in colour)

Answer 1

PPD

lucerin TPO

Ivoclar vivadent

Question 2

What is good about new photo-initiators?

Answer 2

they have a higher visible light absorption rate - increased quantum efficiency

lower quantity of photons to trigger polymerisation

Question 3

What wavelengths is camphorquinone most sensitive?

Answer 3

390-510

PEAK AT 470 NM

Question 4

What is the peak absorption/ peak excitation wavelength?

Answer 4

wavelength at which the maximum excitation of a photolytic chemical occurs

Question 5

What wavelength are PPD, lucerin and TPO most effective?

Answer 5

380 and 430 nm

peak at 470 nm due to camphorquinone being the most common photo-initiator

Question 6

Can the wavelength of the light from curing lamp and the peak absorption of photo-initiator be incompatible?

Answer 6

no, they must be compatible

Question 7

What light will tend to cure all material types?

Answer 7

halogen lights

Question 8

Is conventional LED light curing quite narrow?

Answer 8

yes, 410-480 nm

Question 9

Is the bluephase LED broad in its curing range?

Answer 9

yes

380-515nm

Question 10

What are the 3 types of lights available on the market?

Answer 10

halogen (not used)

plasma

LED (common now)

Question 11

What does LED stand for?

Answer 11

light emitting diodes

Question 12

What are the new LED lights called?

Answer 12

poly wave LED lights

Question 13

What is the benefit of new wave LED lights?

Answer 13

ha more than one LED each operating at a different wavelength

increase compatibility of peak excitation and photo initiator