Furcation: The Problem and Its Management

Definition

It can be defined as: an area of complex anatomic morphology that may be difficult or impossible to be debrided by routine periodontal instrumentation.

Anatomical Considerations

Root trunk Furcation entrance Root surface anatomy Enamel projections Accessory canals

Root TrunkRoot TrunkRoot TrunkRoot TrunkRepresents the undivided Represents the undivided

region of the root.region of the root.

The height of the root The height of the root

trunk is the distance trunk is the distance

between the CEJ and the between the CEJ and the

separation line between separation line between

two root conestwo root cones

Furcation Entrance

Entrance:Entrance: the the transitional area transitional area between the between the undivided and the undivided and the divided divided part of part of the rootthe root

Fornix:Fornix: the roof of the roof of the furcationthe furcation

Furcation Entrance Diameter

How does the furcation entrance diameter relate to the blade width of a new curette?– Blade width of new

Gracey curette = 0.75mm– 60% of molar furcation

entrances < 0.75 mm– Mandibular molars:

buccal wider than lingual maxillary molars:

mesial > distal > buccal

Root Concavities

Mandibular Molars– 100% mesial roots– 99% distal roots

Maxillary Molars– 94% mesiobuccal

roots– 31% distobuccal

roots– 17% palatal roots

Cervical Enamel Projections

13% of molars have CEPs

These projections may favor the onset of periodontal lesions in the affected furcations

Enamel Pearls

Incidence: 1.1% - 9.7%

– Maxillary 2nd molar found near the CEJ extending into molar bifurcations

Glickman`s Classification(1953)

Classification

Class I Incipient FurcationThis is an early lesion. The pocket is suprabony, involving the soft tissue. There is slight bone loss in the furcation area. Radiographic change is not usual since bone loss is minimal. A periodontal probe will detect root outline or may sink into a shallow V-shaped notch into the crestal area

Class I Incipient Furcation

The level of bone loss allows for the insertion of the periodontal probe into the concavity of the root trunk

Class II Patent FurcationIn this, bone is destroyed in one or more aspects of the furcation, but a portion of the alveolar bone and periodontal ligament remain intact, permitting only partial penetration of the probe into the furca. Radiographs may or may not reveal this type of furcation.

Class II Patent Furcation

The level of bone loss allows for the insertion of a periodontal probe into the furcation area between the roots.

Class III Communicating or Through and Through Furcation

This type of probe penetrates completely from one side to the other side characterized by severe bone destruction in the furcation area. It is clearly shown in the radiographs as a radiolucent area in between the roots, especially in the lower molars.

Class IV

As in Class III, but the gingival tissues recede apically so that furcation is clearly visible.

Hamp, Nyman & Lindhe`s Classification (1975)

Tarnow & Fletcher`s Classification (1984)

Vertical bone loss is measured in mm from the roof of the furcation

Furcation Probing

Furcation Probing

Mandibular MolarsBuccal Furcation

Place the probe between the two buccal roots from the buccal aspect

Furcation Probing

Mandibular MolarsLingual Furcation

Place the probe between the two lingual roots from the lingual aspect

Furcation Radiography

Should include both

periapical and bitewing

Location of the

interdental bone and

bone level within the

root complex should be

examined

Pulpal pathosis may some times cause a lesion

in the periodontal tissues of the furcation

Trauma from occlusion may cause

inflammation and tissue destruction within the

interradicular area of a multirooted tooth

Differential Diagnosis

Objective of Treatment

The elimination of the microbial plaque from

the exposed surfaces of the root complex.

The establishment of an anatomy of the

affected surfaces that facilitates proper self-

performed plaque control.

Non-Surgical Root Preparation

Scaling & root planing– Most effective in grade I and shallow grade II.– Deeper sites respond less favorably

In most situations, it results

in the resolution of the

inflammatory lesion in the

gingiva.

Antimicrobials

Adjunct to scaling and root planning

– Chlorhexidine

– Tetracycline fibers

No clinically significant difference in clinical parameters after irrigation

Open Debridement

Greater calculus removal than closed Ultrasonic

– Narrow furcations– Dome of furcation

Surgical access and increased operator experience significantly enhance calculus removal in molar furcation.

Osseous Surgery

Most effective in grade II furcation

Osteoplasty and ostectomy techniques

– Remove the lip of defect to reduce horizontal depth

– Bone ramps into the furcation to enhance plaque control

– Reduce probing depths

Root Resection

Grade II or grade III Contraindications

– Inadequate bone support

– Fused roots

– Inoperable endodontically

– Patient considerations

Sequence of treatment at RSR

Endodontic treatment

Provisional restoration

RSR

Periodontal surgery

Final prosthetic restoration

Factors to be Considered

The length of the root trunk The divergence between the root

cones The length and the shape of the

root cones Fusion between root cones Amount of remaining support

around individual roots Stability of individual roots Access for oral hygiene devices

Hemisection Mandibular molars

– Grade III furcation– Need widely separated roots– Soft tissue positioned below level of pulp

chamber

Hemisection

Root Separation

Root separation involves the sectioning of the root complex and the maintenance of all roots

Grade III furcation

– Permits plaque removal

– Root caries (4% stannous fluoride)

– 25% failure rate at 5 years

– Recurrent periodontitis

Regeneration of Furcation Defects

Guided tissue regeneration Predictable outcome of GTR

therapy was demonstrated only in degree II furcation involved mandibular molars

less favorable results have been reported in other types of furcation defects

GTR could be considered in areas with isolated degree II furcation defects

Furcation DefectsMost predictable Mandibular or

Buccal Maxillary Class II Furcations

Mesial or Distal Maxillary Class II Furcations

Class III Furcations

Least predictable

Osseous Grafting

Autogenous bone Allografts

– Freeze dried bone– Demineralized Freeze dried bone

Alloplasts– Hydroxyapatite

Non-porous Porous

– Bioglass

Extraction

Attachment loss is so extensive that no root can

be maintained

If tooth/gingival anatomy will not allow proper

plaque control

For endodontic or restorative reason

Osseointegrated implant substitute

Prognosis

Hirshfeld and Wasserman. “A long term survey of tooth loss in 600 treated periodontal patients.” J Perio 1978

– 600 patients followed an average of 22 years with recall every 4-6 months

– 1464 molars initially diagnosed with furcation invasion

– 70% survival of furcated molars

Patients Factors

Determine patient`s goals and expectations Screen for local, behavioral and systemic factors;

– Oral hygiene

– Compliance

– Stress

– Intraoral Accessibility

– Uncontrolled Diabetes

– Smoking

– Healing response to Previous Therapy

Successful Patient Outcomes

Function Ease of Care Esthetics Confort Health Value