Treatment of peri-implant defects with combination growth factor cement

The use of growth factor agents in the regeneration of oral tissues is an area of current investigation. Combinations of growth factors have been used synergistically to improve tissue regeneration. The aim of this study was to determine the effects of a combination growth factor cement (GFC) on guided bone regeneration around dental implants.

A combination of bone morphogenetic protein-2 (BMP-2), transforming growth factor-beta (TGF-beta), platelet-derived growth factor (PDGF), and basic fibroblast growth factor (bFGF) was used in a bioabsorbable, non-hydroxyapatite, calcium phosphate cement. Five adult hound dogs were used to compare the effects of GFC, plain cement, and control (no cement). The right and left second, third, and fourth mandibular premolar teeth were extracted; the implant osteotomies were prepared; and a uniform circumferential gap was prepared 1.5 mm beyond the width of the implant in the coronal half of the osteotomy for cement placement. Titanium machine-polished dental implants were placed in the prepared sites, and coronal defects were treated according to previously randomized, assigned modality. A bioabsorbable collagen membrane was secured over the control site, and the flaps were closed primarily. The dogs were maintained on a soft diet to avoid soft tissue trauma. The dogs were sacrificed at 3 months. The specimens were sectioned, mounted, and stained with Stevenel's blue and van Gieson's picric fuchsin. The bone-to-implant contact and bone 1 mm peripheral to the implant surface were recorded with a computerized microscopic digitizer.

The findings of this study indicate a significant effect of GFC on increased bone-to-implant contact and amount of bone per surface area compared with the other treatment modalities (P <0.0009). Plain cement demonstrated slight but nonsignificant increases compared with the control (P>0.05).

GFC increases bone-to-implant contact and bone surface area within peri-implant defects. Further studies may be beneficial to determine the feasibility of its use for other regenerative applications.