implant lecture

Question 1

even pure titanium is commonly mixed with what?

Answer 1

6% aluminum and 4% vanadium

Question 2

alumnim does what

Answer 2

decreases weight and increases strength

Question 3

vanadium does what?

Answer 3

protects from corrosion

Question 4

explain titanium properties compared to others.

Answer 4

greater than stainless steel and human bone tissue

Question 5

speed of oxidation and thickness of the layer affects what?

Answer 5

corrosion rate of each metal

Question 6

what metal is better at avoiding corrosion in water?

Answer 6

gold

Question 7

what metal is better at avoiding corrosion in acid?

Answer 7

titanium

Question 8

after implant is inserted into the body body tissue, the surface oxide of the titanium implant continuously grows by what?

Answer 8

inward transport of oxygen and outward transport of metal atom to form the oxide metal line.

Question 9

the concentration of Titanium ions is _________ as the distance from the oxide-metal increases.

Answer 9

decreased.

Question 10

the tissue implant interface is determined by what?

Answer 10

region of extracellular matrix (collagen & chondroitin sulfate) and Ti oxide, which is located between bulk Ti and cells.

Question 11

outermost surface of titanium oxide has what?

Answer 11

unsaturated bonds, allowing it to easily bind to any contaminants when Ti surface is exposed to air.

Question 12

if implant contaminated, what happens to tissue attachment?

Answer 12

decreased because unsaturated bonds bind to contaminants instead of extracellular matrix proteins

Question 13

what is radio-frequency discharge?

Answer 13

improves implant surface properties. provides plasma-cleaning treatment. argon gas delivered from device, strips contaminants, sterilizes surface and reforms oxide layer. decreases surface angle contact

Question 14

tricalcium phosphate (TCP) properties

Answer 14

low crystallinity, higher biosolubilty, for bone defects.

Question 15

hydroxyapatite (HA) properties

Answer 15

higer crystallinity, not readily biosorable, used for coatings for implants

Question 16

advantages of HA

Answer 16

high compressive strength, good wear properties, and biological compatability

Question 17

disadvantages of HA

Answer 17

low tensile strength, therefor can only apply as thin layer. also low shear strength

Question 18

method to coat implants with HA

Answer 18

plasma coating

Question 19

optimal thickness of HA

Answer 19

50 μm

Question 20

after dental implant is inserted, what happens?

Answer 20

undifferentiated mesenchymal cells from bone marrow attach to surface of implant material

Question 21

cellular attachment facilitated by what?

Answer 21

adhesive proteins like firbonectin and vitronectin

Question 22

While the cells attach to the surface of the implant material, the
cells undergo _________________. this process is promoted by what?

Answer 22

differentiation to osteoblasts. by osteogenic proteins such as osteogenin

Question 23

as a result of implantation, 2 types of bone form?

Answer 23

distant bone and contact bone

Question 24

host osteogenic response to implant materials 4 steps

Answer 24

attachment, differentiation, osteogenesis, mineralization

Question 25

distant bone formation occurs when what?

Answer 25

failure of osteogenic cell attachment to the implant surface

Question 26

layer of soft fibrous tissue (FT) between

the implant material (I) and solid bone tissue

Answer 26

distant bone

Question 27

contact bone formation is an indication of what?

Answer 27

succesfull dental implantation

Question 28

what is contact bone?

Answer 28

when bone comes in contact with implant. no fibrous tissue