Q: Why do we barrel in furcations?

A: By removing the overhanging lip on the furcation, we usually find bone to be more coronal in the furcation, creating a parabolic architecture and maintainable environment. No further breakdown should occur.

Class II furcationTooth #30 exhibits a Class II furcation with the old margin approximating the furcation.

Biologic shapingAfter biologic shaping, the overhang of the furcation is removed to allow for a more maintainable furcation area.

Completed perio-restorative caseCompleted restoration with the contours of the new restoration mimicking the shaped root surface.

You have the opportunity to gather more in-depth information in our author's course Advanced periodontology: surgical protocols by Dr. Daniel Melker.

Q:Why do we barrel in a furcation to the occlusal surface when fabricating a new crown?

A:When we contour the crown so the barreling in goes to the occlusal surface, the patient can clean everywhere; there is no plaque buildup. If we can stop short of the occlusal surface, we find plaque accumulates and it is as though the furcation is still present.

Plaque accumulation

When the furcation is removed and the new restoration places the furcation back in that area, it becomes a location for plaque accumulation.

Biologic shaping, furcation replacing

After biologic shaping, the furcation is replaced and the area accumulates plaque.

Furcation removed

The furcation was removed but replaced in the final restoration. The tissue has become inflamed from the root being replaced because of plaque accumulation.

Q:How do you contour a new restoration once the tooth has been biologically shaped?

A: The new restoration follows the contours of the shaped tooth and does not have a height contour placed on the buccal.

Occlusal view on the day of impression

Occlusal view on the day of impression

Buccal view on the day of impresion

Buccal view on the day of impression

Furcation contouring

Buccal furcation contours carried to the occlusal surface of tooth #30

Q: Should the contours of the new restoration follow the shaped tooth?

A:Yes, to allow for the proper maintenance by the patient and hygienist. As previously discussed, any furcation that is barreled in should be carried to the occlusal surface.

Contours of shaped teeth

Contours of shaped teeth are shown.

Shaped teeth

An occlusal view of shaped teeth and, in particular, barreled in furcation of teeth #30 & 31.

Restorations mimic shaped teeth

Restorations mimic shaped teeth.

Restorations placed on mimic shaped teeth

Restorations placed on teeth mimic shaped teeth

Q:Does vertical probing in the furcation area tell what periodontal issues may exist?

A:No, as the furcation may approximate the old margin, causing the possibility of future problems for the furcation and new crown. It is important to eliminate any furcation present prior to placement of a new restoration.

Minimal periodontal issues

Tooth #30 appears to have minimal periodontal issues, based on tissue appearance.

Flap reflection

Upon reflection of the flap, the existing margin ends in the furcation. A significant problem exists in terms of the furcation breaking down further over time if left that close to the final margin.

Vertical probing

Vertical probing is minimal (2 mm) in the furcation area.

Old margin removing

By removing the old margin and smoothing the furcation area, the problem is solved. The operator can now place a new margin anywhere he or she wishes.

Flap sutured

The flap is sutured just coronal to the bone so as not to expose it. The concept of suturing is to try to get as much primary closure as possible. Better wound healing occurs and less pain is involved with primary closure.

There are additional details that you can discover in course Perio-restorative protocols: team-based approach.

Author information: Daniel Melker

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