Fibroblast growth factor-2 with beta-tricalcium phosphate for the deep and wide intrabony defect reaching the apex and Class II furcation involvement of a mandibular molar.

Abstract

Background: The basic fibroblast growth factor (FGF-2) drug formulation, human recombinant FGF-2 and hydroxypropylcellulose, developed in Japan, has been confirmed to induce effective periodontal regeneration. However, in cases with minimal residual bone walls or vertical bone defects fused with furcation involvement, FGF-2 alone does not achieve ideal periodontal regeneration. Therefore, it is necessary to attempt to use FGF-2 in combination with bone grafting materials. Beta-tricalcium phosphate (β-TCP) has been developed as a bone graft material and has a long history of use. Its advantage lies in its ability to be absorbed early during wound healing and replaced by bone. In this study, we examined the effectiveness of the smallest particle-sized β-TCP in combination with FGF-2 for the severe deep and wide combined one- to three-walled bone defect and Class II furcation involvement.

Methods: FGF-2 with β-TCP was applied to an intrabony defect and Class II furcation involvement of a 40-year-old female patient with aggressive periodontitis (stage III and grade C). As far as possible, the incision line was not placed over the bone defect. The interdental papillae were dissected using a simplified papilla preservation technique. Full-thickness buccal and lingual mucoperiosteal flaps were reflected. After thorough debridement, FGF-2 with small-particle β-TCP was applied to the bone defects.

Results: Radiographic examination at 1 month demonstrated early radiographic bone fill. Over time, layered bone‑like radiopacity was observed extending from the remaining bone wall. In addition, by 6 months, a distinctive protruding bone‑like radiopacity arising from the alveolar crest of the adjacent tooth was observed extending toward the defect. At 41 months, substantial radiographic bone fill was evident. While Class II furcation involvement showed overall improvement, some sites exhibited only limited reparative changes.

Conclusion: The combination of FGF-2 and small‑particle β‑TCP may promote periodontal regeneration in severe intrabony and furcation defects, although definitive confirmation of complete regeneration requires further investigation.

Key points: The optimal β‑TCP particle size for use with FGF‑2 remains unclear. In this study, the smallest available β‑TCP granules were incorporated into the hydroxypropylcellulose‑based FGF‑2 formulation, functioning as a dispersed, space‑maintaining scaffold. Periodontal tissue regeneration using the smallest and rapidly absorbable β‑TCP granules in combination with FGF‑2 demonstrated favorable healing in complex, deep vertical bone defects and Class II furcation lesions. Although larger β‑TCP granules are generally considered advantageous because their greater porosity allows easier migration of undifferentiated mesenchymal cells from existing bone walls or periodontal ligament remnants, the small‑particle β‑TCP used with the FGF‑2 formulation behaved differently. When mixed with FGF‑2, the granules are suspended within the base carrier, creating a highly porous structure that facilitates mesenchymal cell migration.

Plain language summary: Severe periodontal disease often destroys the bone supporting teeth, creating complex defects specifically between tooth roots that are notoriously difficult to treat and often lead to tooth extraction. The periodontal tissue regenerative drug using FGF-2 (basic fibroblast growth factor), one of the cell growth factors, helps promote the formation of new blood vessels and periodontal tissues, but it is often insufficient on its own for large or complex bone defects. In this case study, the combination of the gel‑based FGF‑2 formulation with small granules of beta‑tricalcium phosphate (β‑TCP) supported periodontal tissue regenerative healing. The key to this favorable healing response appears to be the combination itself: although the small‑particle β‑TCP remains dispersed within the FGF‑2 gel rather than forming a densely packed structure, this structure creates necessary space. This spacing likely allows the patient's own repair cells to migrate easily from the surrounding bone into the defect, facilitating effective natural healing and saving the tooth.