Furcation Defect

- Bone loss from aggressive periodontitis can lead to an exposed furcation on a tooth.
- Furcation defect is bone loss affecting the base of the root trunk where two or more roots meet.
- The extent and configuration of the defect are factors in diagnosis and treatment planning.
- Surgical periodontal treatment may be considered to close the furcation defect or improve oral hygiene.
- Furcation defects have a diminished prognosis due to the difficulty of removing periodontal pathogens.

Root Trunk Length

- The distance between the cementoenamel junction (CEJ) and the furcation entrance is called root trunk length.
- Deeper furcation entrances require more bone loss for the furcation to become exposed.
- Mandibular first molars have a mean root trunk length of 3 mm on the buccal aspect and 4 mm on the lingual aspect.
- Maxillary first molars have a mean root trunk length of 3-4 mm on the buccal aspect, 4-5 mm on the mesial aspect, and 5-6 mm on the distal aspect.
- Maxillary first premolars have a mean root trunk length of 8 mm from both mesial and distal.

Furcation Defect Classification

- Furcation involvement can be classified using various methods based on horizontal measurements of attachment loss.
- Glickman's classification includes Grade I (incipient involvement), Grade II (horizontal bone loss), Grade III (through-and-through tunnel), and Grade IV (completely probeable).
- Fedi et al. modified Glickman's classification to include two degrees of a Grade II defect based on vertical bone loss.
- Hamp, Lindhe, and Nyman classified furcation defects by probeable depth, including Class I (less than 3mm), Class II (at least 3mm but not through-and-through), and Class III (entire width of the tooth).

Diagnosis

- Furcation involvement can be checked clinically using a Nabers probe.
- Cone beam computerised technology (CBCT) can also be used to detect furcation.
- Periapical and interproximal intraoral radiographs can help diagnose and locate the furcation.
- Only multirooted teeth have furcation, such as upper first premolars and maxillary and mandibular molars.
- Upper premolars have one buccal and one palatal root, while maxillary molars have three roots and mandibular molars have one mesial and one distal root.

Treatment

- Treatment aims to eliminate bacteria from the exposed root surface and establish proper tooth anatomy for better plaque control.
- Grade I furcation may be treated with scaling, polishing, root surface debridement, or furcationplasty.
- Grade II furcation may require furcationplasty, open debridement, tunnel preparation, root resection, extraction, GTR, or enamel matrix derivative.
- Grade III furcation may be treated with open debridement, tunnel preparation, root resection, GTR, or tooth extraction.
- Tooth extraction is considered if there is extensive loss of attachment or if other treatments will not achieve good results.