Furcations Flashcards
What area of the tooth comprises the root trunk?
The area of the tooth between the CEJ and the roof of the furcation
How often will you be unable to fit an instrument into a furcation?
over 50% of the time
What root pattern is seen in molars as you move posteriorly in the arch?
The roots will be closer together as you progress from 1st to 3rd molars
On maxillary molars, what are the furcation distances for 1st, 2nd, 3rd molars?
1st: mesial furcation = 3.6 mm
2nd: facial furcation = 4.2 mm
3rd: distal furcation = 4.8 mm
On mandibular molars, what are the furcation distances for 1st molars?
Buccal furcation = 2.4 mm
Lingual furcation = 2.5 mm
Where are furcal concavities most likely to occur?
100% of time on Mesial root of Mn Molars; 99% on D of Mn molars; 94% on MB of Mx molars
What are five causes for furcation involvements?
Periodontal disease, trauma from occlusion w/ inflammation, pulpal disease, poor restorations, anatomic variations
Which areas of the mouth will probably have the earliest signs of infection?
Interproximals of MAXILLARY molars
mandibular invaded later
Before ever treating a furcation, what must you do?
Test the tooth for vitality
What are seven anatomical factors associated with furcation invasions?
Cervical enamel projections, furcation entrance width, bifurcational ridges, furcation and root concavities, accessory pulp canals, enamel pearls, and furcation restorations
What is a furcation arrow?
Little radiolucency in the furcae possibly signifying furcation invasion
(has 40% sensitivity)
Do short or long root trunks have better prognosis?
Long - because a short root trunk requires less bone loss before the furcation is exposed and invaded
How do you diagnose furcation invasion?
Use Nabors probe and radiograph
the absence of a furcation arrow means what?
It does not rule out invasion
According to Hamp, what classifies a Grade 1, 2, and 3 furcation?
Grade 1 = horizontal access 3mm
Grade 3 = through and through
According to Glickman classifications, what makes a Grade 1, 2, 3, and 4 furcation?
1 = incipient lesion, no bone loss 2 = some furcal bone loss 3 = thru & thru, not clinically visible 4 = thru & thru, clinically visible
According to the Tarnow and Fletcher system, what classifies an A, B, and C furcation?
A = vertical probe 1-3mm B = 4-6mm C = >7mm
Study by Bower in 1979 showed?
81% of all furcation entrances measure
What is the significance of an enamel pearl?
enamel prevents CT attachment, possibly predisposing the area to attachment loss
Study by Moscow & Kanut in 1990 show what about enamel pearls?
incidence ranging from 1.1 - 9.7%, and more common on 2nd and 3rd Mx molars
Bissada & Abdelmalek (1973) observed a __% association between ______ and ______.
50% association between cervical enamel pearls and furcation invasion
How are Grade 2 and 3 cervical enamel pearls different?
Grade 2 approaches but doesn’t enter the furcation, whereas Grade 3 CEPs enter the furcation
What incidence is reported for maxillary and mandibular accessory pulp canals?
Mx: 27.4 - 76%
Mn: 29.4 - 63%
Many studies, including Ramfjord (1987) report what about prognosis of teeth w/ furcation involvement?
That they’re more likely to be lost.
Duh. ;)
What’s one technique for removing calculus in a furcation?
Use of a rotary diamond burr
How should you treat Class I furcation lesions?
S/RP
How should you treat Class II furcation lesions?
Possible flap surgery, and/or GTR on mandibular molars
Regarding guided tissue regeneration, a deeper initial defect has what effect on prognosis?
Better 1 year prognosis
For maxillary molar furcation therapy, which site shows the best improvement after therapy?
Buccal furcation
