Furcation Involvement: Anatomy and Glickman Classification

Furcations

• Furcation is the anatomical area where the roots divide.
• A furcation defect, also called furcation involvement, refers to bone loss at the branching point of roots.
• Furcations are present on multi-rooted teeth, not single-rooted teeth.

Key Anatomical Features

• Features include root trunk length, root cones length, and inter-radicular bone level.

Variations in Furcations

• Not all furcations are the same due to differences in root anatomy.
• Variations include differences in the furcation index grade, root trunk length, root length, interradicular dimensions, cervical enamel projections, and enamel pearls.

Grading

• Grading assists in the recording and subsequent monitoring of clinical findings.
• The amount of bone loss and gingival recession determines the severity of the furcation adn therefore the numerical index grade.

Glickman Classification

• Glickman Classification is a furcation index, created 1953.
• Grade I: Curvature between roots is detected with a probe, but it cannot enter the space.
• Grade II: Probe penetrates the furcation, but does not completely pass through to the other side.
• Grade III: Probe passes completely through the furcation, but is not clinically visible because soft tissue still fills the defect.
• Grade IV: Probe passes completely through the furcation, and the entrance is clinically visible due to gingival recession.

Universally Accepted Furcation Indices

• Glickman 1953
• Hamp, Nyman & Lindhe 1975
• Lindhe 1983
• Tarnow & Fletcher 1984

Root Trunk Length

• Root trunk length is the distance from the cement enamel junction to the entrance of the furcation and root length.

Interradicular Dimensions

• Consider the degree of separation and difference of number of roots diverging.
• Each tooth is different

Cervical Enamel Projections/Enamel Pearls

• EP is the extension of enamel beyond the CEJ in an apical direction towards the furcation area
• Consider the impact of these dental features.

Challenges of Furcation Involvement

• For the patient: may be unsightly, lead to food packing, is difficult to clean, causes sensitivity with exposed dentine/possible root caries, and impacts prognosis.
• For the clinician: complex treatment considerations, may need specialist intervention, variance in presentation and treatment needs, challenging access.

Examination process

• Patient concerns > Gingival tissues > Secondary factors > Radiograph > Assessment of furcation > Recession > Probing depth

Assessment and Grading

• Assessment and grading should be done using the Nabers probe.

Gingival Tissues

• When examining and recording gingival tissues note signs of inflammation, probing depths, and recession.

Role of Radiographs

• Radiographs are used to identify bone loss in a furcation.

Secondary Factors

• This includes overhanging restorations, crown margins, possible accessory root canals, and calculus deposits.

Accessory Canals

• An accessory canal represents a junction of the main pulp canals or the pulp chamber, which communicates with the root surface.
• Frequently identified in the furcation area, indicating the need for Root Canal Therapy (RCT).

Treatment Objectives

• Removal of bacterial plaque/biofilm.
• Removal of secondary local factors.
• Prevent further attachment loss.
• Maintain the function of the tooth.
• Patient education on Oral Hygiene Instructions (OHI).

Oral Hygiene Coaching

• Oral hygiene coaching assists with optimal plaque control in the long term.
• Into furcation with interspace brush and or interdental brush.

Debridement Instruments

• Debridement instruments are used in furcation, including personal choice instruments, specifically designed instruments, and power-driven scalers with assorted working ends.

Initial Treatment Options

• Patient education and motivation.
• Oral hygiene coaching support.
• Non-surgical periodontal therapy.
• Careful and regular monitoring.

Restorative Treatment Options

• Endodontic therapy.
• Periodontal surgery.
• Possible restorative treatment.

Further Treatment Options

• Refer for surgery, including Guided Tissue Regeneration (GTR), Guided Bone Regeneration (GBR), Root Resection, Root Separation,and Furcation Plasty.

Furcation Plasty

• Involves odontoplasty to remove tooth substance and osteoplasty to remodel alveolar bone at the furcation entrance.

Guided Tissue/Bone Regeneration

• Guided bone regeneration (GBR) and guided tissue regeneration (GTR) are dental surgical procedures that use barrier membranes to direct the growth of new bone and gingival tissue.

Root Separation

• Separation involves sectioning of root complex and maintenance of all roots.
• Success depends on the length and shape of roots, divergence/ stability of the root, successful RCT, and good plaque control by the patient.

Root Resection

• Resection involves sectioning and removal of one or more roots.
• Success depends on the length and shape and stability of the remaining root, the amount of support on remaining root, having successful RCT, and good plaque control by the patient.

Monitoring

• Monitoring the tooth with a furcation includes grading, recording, repeating at appropriate recall intervals, and reinforcing OHI.

Prognosis

• Prognosis will be influenced by the general periodontal status, age, consistent plaque control, smoking habits, and bruxism.
• Consider the specifics of a careful examination of furcation areas when completing periodontal examination

Summary

• Inform / educate / advise the patient
• Consider the relevant treatment modality for the furcation
• Maintain and monitor
• If furcation progression occurs consider periodontal specialist referral.