This study evaluated the validity of furcation probing and radiographic assessment of furcation involvement compared to visual assessment during open flap surgery. 939 molars in 215 patients were examined. Agreement between furcation probing and open flap surgery was 56%, with 15% overestimated and 29% underestimated. Radiographic assessment showed 52% agreement with open flap surgery. Both methods underestimated class III furcations. Experience level and tooth anatomy affected radiographic accuracy. The study concluded that a combination of radiographs and probing provides the most reliable furcation assessment.

1. Periodontal Probing Versus Radiographs
for the Diagnosis of Furcation Involvement.
Christian Graetz , Anna Plaumann , Jan-Fredrik Wiebe , Claudia
Springer ,Sonja Salzer and Christof E.Dorfer.
J Periodontol 2014;85:1371-1379
Dr Shivani Iyer
PG 1st Year
Army College Of Dental Sciences

2. CONTENTS
1. Introduction
2. Materials and Methods
3. Results
4. Discussion
5. Related Studies
6. Conclusion
7. References

3. INTRODUCTION
The progress of inflammatory periodontal disease , if unabated ,
ultimately results in attachment loss sufficient enough to affect the
bifurcation or trifurcation of multirooted teeth.
The furcation is an area of complex anatomic morphology, that may be
difficult or impossible to debride by routine periodontal instrumentation.
What is FURCATION ?

4. TERMINOLOGY
Root complex is the portion of a tooth that is
located apical of the cemento-enamel junction
(CEJ).
The root complex may be divided into two parts:
a. The root trunk : represents the undivided
region of the root
b. The root cone : is the divided region of
the root complex.
The furcation is the area located between
individual root cones.

5. Furcation entrance :the transitional area between the undivided
and the divided part of the root
Furcation fornix :the roof of the furcation
Degree of separation :the angle of separation between two roots
cones.
Divergence :distance between two roots.
Divergence and degree of separation between palatal and mesial roots.

6. ANATOMY OF MAXILLARY MOLARS
Mesial view of maxillary 1st molar
Mesial furcations located 2/3rd
towards palate.
 Furcation probed from palatal
side.
Distal view of maxillary 1st molar
Located mid-way buccolingually.
Probing from both the sides.
A. B.

7. DIAGNOSIS
1. Clinical Examination
2. Careful Probing
3. Radiographic View
4.Transgingival sounding.

8. NABERS PROBE
Furcation areas can be best evaluated with the curved , blunt Nabers Probe.
These are of two types :-
1. Nabers 1N Probe : specifically designed for mesial & distal
furcations on maxillary molar.
2. Nabers 2N Probe : accesses all buccal and lingual furcations
and mesial and distal furcations. It also
facilitates access to any furcation with a
long root trunk and/or deep pocket.

9. ETIOLOGY
Prolonged presence of microbial dental plaque.
Extent of attachment loss on furcation depends on the presence of
these factors :
Root trunk length
Root length
Root form
Interradicular dimension.
Anatomy of Furcation.
Cervical enamel projections.

10. Classification of Furcation Involvement

11. Glickman’s Classification ( 1953 )
1. GRADE I
This is an early or incipient stage of furcation
involvement.
The pocket is suprabony and primarily affects the soft
tissues.
Early bone loss may have occurred with an increase in
probing depth.
Radiographic changes not found.

12. 2. GRADE II
Furcation lesion is essentially cul-de-sac, with
a definitive horizontal component.
Vertical bone loss may be present.
Radiographs may or may not depict the furcation
involvement particularly in maxillary molars
because of the radiographic overlap of the roots

13. 3. GRADE III.
In grade III furcation , the bone is not
attached to the dome of the furcation.
In early Grade III involvement , the opening
may be filled with soft tissue & may not be
visible.
The clinician may not be able to pass the
periodontal probe through the furcation because
of the interference with the bifurcational ridges
or facial/lingual bony plate margins.
Properly exposed and angled radiographs of
early class III furcation display the defect as a
radiolucent area in the crotch of the tooth.

14. 4. GRADE IV
The interdental bone is destroyed.
Soft tissues have receded apically so that the
furcation opening is clinically visible.
A tunnel therefore exists between the roots of
such an affected tooth.

15. Hamp, Lyman & Lindhe (1975 )
This classification is based on the amount of periodontal tissue destruction
that has occurred in the inter – radicular area , i.e degree of horizontal root
exposure or attachment loss that exists within the root complex.
Degree I : horizontal loss of periodontal support not exceeding one
third of the width of the tooth.
Degree II : horizontal loss exceeding 1/3rd of the width of the tooth.
not encompassing the total width of the furcation area.
Degree III : horizontal “through and through” destruction of the
periodontal tissues in the furcation area.

16. TARNOW/ FLETCHER ( 1984)
A- Vertical destruction of bone upto 1/3rd of the inter-radicular height (0-3mm)
B-Vertical destruction of bone upto 2/3rd of inter-radicular height (4-7mm)
C- Vertical destruction beyond the apical third (>7mm)
Takes into account vertical bone loss from roof of furcation apically

17. To evaluate the validity of FURCATION PROBING ( FP ) and
RADIOGRAPHIC ASSESSMENT of FURCATION INVOLVEMENT
(FI) compared with visual assessment during OPEN FLAP SURGERY (
OFS )
AIM OF THE STUDY

18. MATERIALS AND METHODS

19. 215 patients
Analysed in the study.
91 males and 124 females
Age : 23 – 67 years
834 molars
Observation time of 16 years
238 patients
One 1st or 2nd Molar treated with OFS during APT
TOTAL = 939 MOLARS
23 excluded
Delayed period of time > 1.5 yrs b/w radiographic
documentation & FP of furcation or date of OFS.
Assessed for eligibility N= 310
Qualified for the study
Received Maintenance therapy >10 years
Presenting 50 % bone loss at a minimum 2 teeth.
1 visit per year after non surgical/active periodontal therapy.
Annual pocket probing depth & complete radiographs at T0 ,
T1 ( end of APT ) & T3 ( last documented visit of maintenance
therapy )
STUDY DESIGN

20. 1. A total of 834 molars were assigned for FI by FP and in radiographs
analyzed by an experienced (EE) and less experienced examiner (LE).
2. For the investigation, 143 panoramic radiographs (OPG) and 77 intra-oral
radiographs (I-O) were evaluated.

21. RESULTS

22. Kappa k
Kappa co-effiecient is intended to give the reader a quantitative measure
of the magnitude of agreement between observers.
Kappa Agreement
< 0 Less than chance agreement
0.01–0.20 Slight agreement
0.21– 0.40 Fair agreement
0.41–0.60 Moderate agreement
0.61–0.80 Substantial agreement
0.81–0.99 Almost perfect agreement

23. FP Region Confirmed by
OFS ( % )
Overestimated
compared with
OFS ( % )
Underestimated
Compared with
OFS ( %)
TOTAL 56.2 14.8 29.0
Maxilla 53.8 16.3 29.9
Mandible 59.3 12.9 27.9
Agreement of FI Diagnosed by Clinical Probing With a Nabers
Probe (FP) Compared with the Situation Observed During OFS
The degree of agreement between FP & OFS was slightly better for Mandible
( 59.3 % , k = 0.629 ) compared with the maxilla ( 53.8 % , k = 0.550)
The class of FI by FP was confirmed in 56 % , whereas 15 % were
overestimated & 29 % underestimated.

24. The best correlation of FP and OFS was found in the mandible for the
first left molar (kw = 0.690) and in the maxilla for the second right molar
(kw = 0.637 )
Of all furcations diagnosed as Class III during OFS, 68.1% were not
detected correctly by FP (maxilla 66.2% and mandible 71.4%).
The mean agreement between FP and OFS for all investigators was kw
= 0.588

25. Radiographic Diagnosis Versus Assessment During OFS
Overall, 524 furcations were analyzed by OPG & 310 by I-O.
The LE was not able to evaluate the FI in 30 cases (3.6% of 834 molars) and
set these as FI Class ‘‘f’’ (EE: no cases).
Furthermore, LE did not find any FI Class II by OPG or I-O.
Missing an FI Class III by radiographs was more likely in the maxilla
compared with the mandible.

26. The agreement of OFS and radiographs was kw = 0.542 (OPG kw = 0.555 and I-
O kw =0.521) for both examiners.
A slightly better agreement was found for the mandible, with 52.3% (kw = 0.619)
versus 44.5% (kw = 0.477) in the maxilla.
The best correlation of OPG and OFS was found at the first left molar in the
mandible (EE kw = 0.876; LE kw = 0.629).

27. Influence of Examiner Experience and Tooth Anatomy
Overall the accuracy of the FI assessment by radiography seemed to
depend on the examiner’s experience :
EE kw = 0.618
LE kw = 0.426

28. DISCUSSION
This retrospective study evaluates whether clinical, radiographic, or a
combined assessment of FI is most reliable to assess the degree of FI.
The advantage of this study design, aside from the large number of
participants, is that the examinations were performed under the conditions of
daily clinical practice by periodontists unaware of their participation in a study.
Study-related effects, such as a bias of the examiners, e.g., during clinical
probing, could therefore be excluded.

29. ACQUISITION OF IMAGES
CONVENTIONAL VS. DIGITAL IMAGING METHODS
According to the study design of the current investigation, the authors
used only conventional radiographs under the conditions of daily practice
without any standardization devices.
Despite the extensive innovations in imaging methods in recent years,
the traditional method of obtaining an image has basically remained the
same.
Current imaging methods in periodontology have been thoroughly
reviewed by Mol *.
The study concluded that digital imaging per se is not superior to film
based radiographs in its ability to detect detailed periodontal structures.
*Mol A. Imaging methods in periodontology. Periodontol 2000 2004: 34: 34–48.

30. It seems indisputable that the force during clinical probing of the furcation the
size and design of the probe and the experience and the training of the examiner
influence the clinical assessment of the FI.

31. Kims TS et al ( 1982 )* studied the reproducibility & validity of
furcation measurements using the pressure - calibrated probe.
( 0.25 N ) which is a flexible plastic universal version of the TPS ( True
Pressure Sensitive ) probe.
The horizontal probing attachment level (PAL-H) of 100 furcation
involved molars on 25 patients was investigated
The measurements were repeated using a colour-coded Nabers probe
and compared to the TPS assessments.
The study concluded TPS probe unsuitable for proper assessment of
the degree of furcation involvement.
* Kim TS, Knittel M, Staehle HJ, Eickholz P. The reproducibility and validity of furcation measurements
using a pressure-calibrated probe. J Clin Periodontol 1996;23:826-831.

32. 1. Ross IF, Thompson RH Jr et al
Study found a more reliable assessment of FI in maxillary molars by radiography
than by clinical examination, which was opposite for the mandible. The findings
for the maxilla corresponded to the present results.
2. Gurgan et al evaluated radiographic assessment of artificial bony defects
with the corresponding buccal FI Class I and II in the mandible with a high
correlation within the 12 observers (68% and 86%) and without significant
difference between mandibular first and second molars, similar to the present
investigations
RELATED STUDIES

33. 3. Eickholz and Kim showed that straight probes may increase the
underestimation of diagnosis and, therefore, recommended curved probes
as used in this study.
4. Zappa et al. in a similar investigation with six involved dentists after
diagnosis of 1,180 clinical furcations found a higher degree of agreement
of clinical probing to OFS for mandibular molars. ( k = 0.629 )

34. CONCLUSION
For experienced operators , the combination of radiographic imaging of furcations
and clinical probing is most reliable.
It cannot be concluded by the data of this study which degree of clinically
examined FI necessitates further radiographic diagnostic techniques such as I-O or
OPG.
Therefore , the gold standard remains visual control during OFS.

35. REFERENCES
1. Carranza’s Clinical Periodontology, 10th edition.
2. Clinical Periodontology & Implant Dentistry , 5th edition Volume 2 – Jan Lindhe
3. Fleiss JL, Cohen J, Everitt BS. Large sample standard errors of kappa
and weighted kappa. Psychol Bull1969;72:323-327.
4. Bragger U. Radiographic parameters: Biological significanceand clinical
use. Periodontol 2000 2005;39:73-90.
5. Mol A. Imaging methods in periodontology. Periodontol2000 2004: 34: 34–48.
6. Kim TS, Knittel M, Staehle HJ, Eickholz P. The reproducibility and validity of
furcation measurements using a pressure-calibrated probe. J Clin Periodontol
1996;23:826-831.