November 04, 2024
The teeth located at the back on both the upper and lower jaws have more than one root. The part of the tooth structure from where these roots divide is called the furcation. If a tooth has two roots, the common point on the trunk of the root is called the bifurcation. In case the tooth divides into three roots, the point is called the trifurcation. The furcation is a crucial anatomical landmark on the surface of the tooth. It has a significant effect on the health of the periodontium, a complex of supporting tissues that support the tooth.
Etiology
Accumulation of debris and plaque on the surface of the tooth causes inflammation of the gums. When oral hygiene is not maintained properly, this inflammation can spread deeper into the periodontium. A pocket is formed, wherein a tunnel like pathological formation occurs between the tooth and the gums covering it. This causes the gums to recede and subsequent loss of the underlying bone.
Some developmental pathologies like ectopic formation of enamel can facilitate furcation defects. In some other cases, excessive forces on the tooth due to normal bite can cause loss of bony structure adjacent to the furcation area. This is called trauma from occlusion.
A tooth already treated with a restoration can also suffer from a furcation defect if the restoration interferes with normal bite and thus indirectly causes trauma from occlusion.
Diagnosis and classification of furcation defects
There are at least 20 published scientific articles that have tried to classify the furcation defects in order to ease the diagnosis and subsequent treatment plan. Most of these classifications are based on the direction in which the furcation defect is present, the presence or absence of a pocket and the status of the gingiva. The most advocated classification was given by Irving Glickman, who gave four grades of severity of furcation defects.
Diagnosis of furcation defect is done by exploring the furcal area with a probe. Radiographs with multiple angulations or a CBCT is used to confirm the diagnosis. Based on this, a treatment plan is formulated.
The first grade of furcation defect sees only an initial lesion with pocket formation restricted to the crown of the tooth. Bone loss may or may not have initiated and is rarely appreciated on the radiograph.
The second grade of furcation defect is such, that a probe can be passed at the furcation. However, there is still significant amount of bone present. The tooth might show some mobility.
Grade three of furcation defect is seen when the probe is passed through the furcation from one end and reaches the other end. However, the other end still houses some bony structures and so the probe cannot be passed through the furcation. It resembles a tunnel with one end closed. The gingiva might not recede as much and it is highly likely that it covers the furcation area.
The fourth and the final grade involves a through and through defect of the furcation region with substantial bone loss which is appreciable on the radiograph as well.
Treatment
The treatment of furcation defects is based on the grade of the defect. Simultaneously, the patient's age, overall health, oral hygiene and esthetic demands must also be met.
A Grade I defect can be treated through scaling and root planning or by furcationplasty. Scaling and root planning means cleaning and debriding the furcation area from the debris and calculus. This can facilitate healing of the tissues and subsequent decrease in the inflammatory levels. Furcationplasty is a procedure in which the gingival tissue is repositioned in a way it covers the furcation area. A procedure called odontoplasty is also a part of the furcationplasty procedure where the crest of the bone and the furcation area are recontoured to eliminate any irregularities.
A Grade II defect can be eliminated by a combination of scaling and root planning and tunnel preparation. Tunnel preparation is a procedure where the furcation defect is intentionally created through and through. This is done in patients with better plaque control and good oral hygiene. The aim is to facilitate healing of the pockets and gingiva below the root trunk. However, this procedure increases the chances of root decay and the patient must be warned about the same.
A Grade III and Grade IV defect can be treated through more invasive and complex procedures like root resection, where one or more roots are removed. However, this option is viable only if there is sufficient bone to support the remaining roots. Some defects can be corrected through bicuspidization and hemisection, where a root, and the part of the crown corresponding to it are removed.
Current concepts for treating furcation defects include bone grafts, guided tissue regeneration, placement of enamel matrix and stem cell therapy. These strategies target the regeneration and formation of cells of the periodontium that eventually eliminate the furcation defect.
In hopeless cases of furcation defect, extraction of the tooth is the best option. This option is preferred when any of the above-mentioned treatment plans fail and the patient is unable to maintain his or her oral hygiene.
A routine dental check-up can keep the patient's oral hygiene in check. Clinical assessments and radiographs taken during these visits can help in monitoring the bony health surrounding the tooth structures which can ultimately help in timely diagnosis of furcation defect.