Furcations

Question 1

What area of the tooth comprises the root trunk?

Answer 1

The area of the tooth between the CEJ and the roof of the furcation

Question 2

How often will you be unable to fit an instrument into a furcation?

Answer 2

over 50% of the time

Question 3

What root pattern is seen in molars as you move posteriorly in the arch?

Answer 3

The roots will be closer together as you progress from 1st to 3rd molars

Question 4

On maxillary molars, what are the furcation distances for 1st, 2nd, 3rd molars?

Answer 4

1st: mesial furcation = 3.6 mm
2nd: facial furcation = 4.2 mm
3rd: distal furcation = 4.8 mm

Question 5

On mandibular molars, what are the furcation distances for 1st molars?

Answer 5

Buccal furcation = 2.4 mm

Lingual furcation = 2.5 mm

Question 6

Where are furcal concavities most likely to occur?

Answer 6

100% of time on Mesial root of Mn Molars; 99% on D of Mn molars; 94% on MB of Mx molars

Question 7

What are five causes for furcation involvements?

Answer 7

Periodontal disease, trauma from occlusion w/ inflammation, pulpal disease, poor restorations, anatomic variations

Question 8

Which areas of the mouth will probably have the earliest signs of infection?

Answer 8

Interproximals of MAXILLARY molars

mandibular invaded later

Question 9

Before ever treating a furcation, what must you do?

Answer 9

Test the tooth for vitality

Question 10

What are seven anatomical factors associated with furcation invasions?

Answer 10

Cervical enamel projections, furcation entrance width, bifurcational ridges, furcation and root concavities, accessory pulp canals, enamel pearls, and furcation restorations

Question 11

What is a furcation arrow?

Answer 11

Little radiolucency in the furcae possibly signifying furcation invasion
(has 40% sensitivity)

Question 12

Do short or long root trunks have better prognosis?

Answer 12

Long - because a short root trunk requires less bone loss before the furcation is exposed and invaded

Question 13

How do you diagnose furcation invasion?

Answer 13

Use Nabors probe and radiograph

Question 14

the absence of a furcation arrow means what?

Answer 14

It does not rule out invasion

Question 15

According to Hamp, what classifies a Grade 1, 2, and 3 furcation?

Answer 15

Grade 1 = horizontal access 3mm

Grade 3 = through and through

Question 16

According to Glickman classifications, what makes a Grade 1, 2, 3, and 4 furcation?

Answer 16

1 = incipient lesion, no bone loss
2 = some furcal bone loss
3 = thru & thru, not clinically visible
4 = thru & thru, clinically visible

Question 17

According to the Tarnow and Fletcher system, what classifies an A, B, and C furcation?

Answer 17

A = vertical probe 1-3mm
B = 4-6mm
C = >7mm

Question 18

Study by Bower in 1979 showed?

Answer 18

81% of all furcation entrances measure

Question 19

What is the significance of an enamel pearl?

Answer 19

enamel prevents CT attachment, possibly predisposing the area to attachment loss

Question 20

Study by Moscow & Kanut in 1990 show what about enamel pearls?

Answer 20

incidence ranging from 1.1 - 9.7%, and more common on 2nd and 3rd Mx molars

Question 21

Bissada & Abdelmalek (1973) observed a __% association between ______ and ______.

Answer 21

50% association between cervical enamel pearls and furcation invasion

Question 22

How are Grade 2 and 3 cervical enamel pearls different?

Answer 22

Grade 2 approaches but doesn’t enter the furcation, whereas Grade 3 CEPs enter the furcation

Question 23

What incidence is reported for maxillary and mandibular accessory pulp canals?

Answer 23

Mx: 27.4 - 76%
Mn: 29.4 - 63%

Question 24

Many studies, including Ramfjord (1987) report what about prognosis of teeth w/ furcation involvement?

Answer 24

That they’re more likely to be lost.

Duh. ;)

Question 25

What’s one technique for removing calculus in a furcation?

Answer 25

Use of a rotary diamond burr

Question 26

How should you treat Class I furcation lesions?

Answer 26

S/RP

Question 27

How should you treat Class II furcation lesions?

Answer 27

Possible flap surgery, and/or GTR on mandibular molars

Question 28

Regarding guided tissue regeneration, a deeper initial defect has what effect on prognosis?

Answer 28

Better 1 year prognosis

Question 29

For maxillary molar furcation therapy, which site shows the best improvement after therapy?

Answer 29

Buccal furcation