Accessory retention

Question 1

Additional retention; more than the primary retentive features of your prep:

Answer 1

accessory retention

Question 2

Accessory retention is often used with large restorations especially _____

Answer 2

amalgam

Question 3

Amalgam relies completely on:

Answer 3

mechanical retention

Question 4

Accessory repentino does NOT:

Answer 4

seal or increase strength

Question 5

Accessory retention has no effect on:

Answer 5

resistance form

Question 6

Accessory retention is required when:

Answer 6

the residual tooth structure does not provide adequate retention

Question 7

Indications for pin placement include:

Answer 7

1. to improve retention
2. extensive preparations
3. prognosis of tooth is uncertain

Question 8

Contraindications for pin placement include:

Answer 8

1. severe loss of tooth structure
2. endo treated teeth
3. large pulp canals
4. difficult access
5. tooth already serves as abutment for partial denture

Question 9

The pin does not ______, its only function is to provide additional _____ & ______

Answer 9

strengthen the amalgam; retention and or resistance

Question 10

What do the placement of pins REDUCE in amalgam?

Answer 10

compressive and transverse strength (disadvantage)

Question 11

Pin placement may introduce stresses into the _____ which can lead to crazing or even fracture

Answer 11

dentin

Question 12

Types of accessory retention in VITAL teeth include:

Answer 12

1. pins
2. slots and grooves
3. amalgapins

Question 13

What accessory retentive feature in VITlAL teeth removes the least amount of tooth structure?

Answer 13

pins

Question 14

Because you cannot use pins in endo treated teeth due to fracture risk, you instead can use:

Answer 14

1. amalgam core (retention from pulp chamber)
2. post retained amalgams (post placed in actual canal not dentin)

Question 15

The pin is ALWAYS placed into the:

Answer 15

dentin

Question 16

What type of pins are available?

Answer 16

1. cemented
2. friction lock
3. SELF-THREADING*

Question 17

A self threading pin is _____ times as retentive as a cemented pin

Answer 17

5-6x

Question 18

There should be at least _____mm of dentin around a pin hole with a self threading pin:

Answer 18

1.0 mm

Question 19

What type of pins are used most frequently at UMKC?

Answer 19

Self threading

Question 20

Self threading pins are self ______ meaning:

Answer 20

self-shearing; they break off on their own during placement

Question 21

If multiple pins are placed, they should be placed ideally _______ mm apart from each other but at a minimum _____ mm apart from eachother

Answer 21

5.0mm ; 3.0mm

Question 22

How far away from the wall of the prep should pins be placed?

Answer 22

1.0mm but a minimum of 0.5mm

Question 23

How deep into the dentin should a pin go?

Answer 23

2.0mm

Question 24

Not only is this type of pin most common (99% used) but is also the most RETENTIVE:

Answer 24

Self-threading

Question 25

Increased diameter of a pin=

Answer 25

increased retention

Question 26

If you place a pin and it breaks, you should place another one:

Answer 26

1.5mm from away from broken pin

Question 27

What is the diameter of the most frequently used threaded pin? What is this called?

Answer 27

0.021 inches; Minim

Question 28

What is the general rule to pin placement?

Answer 28

Use one pin per missing cusp, axial wall, or line angle & use no more than 4 pins/tooth

Question 29

T/F: the pin should be placed 2.0mm into the dentin, have 1.0mm of dentin minimum surrounding it, be placed with the long axis of the tooth and be placed in the line angles of the tooth (the greatest area of bulk)

Answer 29

true

Question 30

What type of hand wrench is used at UMKC?

Answer 30

Link series and Link plus

Question 31

Pinhole location depends upon:

Answer 31

1. pulpal anatomy 2. external tooth anatomy 3. patient age

Question 32

The best sites for pin placement are at:

Answer 32

line angles (DF, DL, MF, ML)

Question 33

Sites to AVOID for pin placement (to avoid pulp exposures):

Answer 33

1. MF corner of maxillary & mandibular 1st molar 2. Distal of mandibular molars 3. Lingual of maxillary molars 4. Mid-facial, mid-medial, and mid-distal furcations of maxillary 1st & 2nd molars

Question 34

What concavities should we watch out for when placing a pin?

Answer 34

1. mesial concavity over max 1st PM 2. Mid-lingual & mid-facial of mand 1st & 2nd molars 3. mid-facial, mid-medial, and mid-distal furcations of max 1st & 2nd molars

Question 35

The pin should be placed a minimum of ______mm inside the DEJ or a minimum of ______ from the external surface of the tooth, whichever is greater

Answer 35

0.5 mm (preferably 1.0 mm inside the DEJ); 1.0 mm

Question 36

If planning to place a crown the pin should be placed ______mm inside the DEJ (earlier it was 0.5mm minimum- 1.0mm inside the DEJ with no crown)

Answer 36

1.0-1.5

Question 37

When placing a self-threading pin, make sure you have a:

Answer 37

positive stop

Question 38

What should be done at the end of placing a self-threading pin?

Answer 38

Quarter turn reverse at the end (reduces stress)

Question 39

There must be ______ of amalgam over the top of the pin, otherwise the amalgam may frature

Answer 39

2.0mm

Question 40

When cutting the pin, it should be stabilized using:

Answer 40

forceps

Question 41

When cutting the pin if you notice that its loose what should you do?

Answer 41

remove and use a larger size pin

Question 42

T/F: use a condenser to push on the pin & flatten it

Answer 42

false- use pin bender only

Question 43

Summary of procedure for drilling pin holes: 1. place ____ inside the _____ 2. place _____ with a _____ bur 3. confirm correct ____ 4. continuous _______ (in and out ____) 5. interpin distance of _____

Answer 43

1) 0.5mm; DEJ 2) pilot hole; 1/4 round 3) angulation 4) drilling; one time 5) 3-5mm

Question 44

Although both are bad, what is more preferable- pulpal perforation or PDL perforation with pin placement?

Answer 44

pulpal perforation (because extirpation of pulp solves the problem)

Question 45

A periodontal perforation with a pin usually results in:

Answer 45

abscess

Question 46

Slots and groove should be placed _____ inside the ____

Answer 46

0.5; DEJ

Question 47

Slots are similar to grooves but are:

Answer 47

larger

Question 48

Slots are created with a ______ bur

Answer 48

33 & 1/2 inverted cone bur

Question 49

How wide and deep should slots be?

Answer 49

0.5-1.0 mm wide & 1.0mm deep

Question 50

Slots should be slightly _____ to provide retention

Answer 50

undercut

Question 51

Allow for restorative material to act as "pin":

Answer 51

locks

Question 52

With _____ more tooth structure is removed a) slots b) pins c) grooves d) locks

Answer 52

Locks (may be slots?)

Question 53

_____ result in fewer micro fractures compared to pins

Answer 53

slots

Question 54

When creating an amalgam pin use a ____ bur. Drill hole _____ wide, ____ deep and then:

Answer 54

#245 bur; 1mm wide and 2mm deep; condense amalgam into pin hole

Question 55

Benefits of using amalgam buildup: 1. can ____ when preparing crown 2. ease of ___ 3. good _____ properties 4. not as ____ as composite resin 5. good ____ stability 6. good _____ resistance 7. relatively ____

Answer 55

1. visualize 2. manipulation 3. mechanical 4. technique sensitive 5. dimensional 6. wear 7. inexpensive

Question 56

What is absolutely critical when performing an amalgam buildup?

Answer 56

stabilization of matrix band

Question 57

Slots, locks, grooves, amalgapins and pins can all be combined to provide retention and resistance for a complex amalgam restoration. Place _____, ____, ____ before placing _____

Answer 57

slots, locks, groove, pinhole