The purpose of this study was to investigate the effect of 2 growth factors, platelet-derived growth factor-BB (PDGF-BB) and insulin-like growth factor-1 (IGF-1), alone or in combination, on the adherence of human periodontal ligament fibroblast (PDL) to tetracycline HCl (TTC) conditioned and nonconditioned periodontally involved root surfaces. There were 80 root dentine chips from 80 patients, ranging from 35 to 70 years of age, each with one periodontally involved tooth requiring extraction. A root dentine chip was obtained from the subgingival surface opposite to the periodontal pocket of each extracted tooth. The dentine chips were randomly distributed into one of 8 groups. In group 1, PDL fibroblasts were cultured and allowed to attach on the dentine surface. In group 2, PDL fibroblasts were cultured on a PDGF-BB pre-treated dentine surface and in group 3, they were cultured on a IGF-1 pre-treated dentine surface. In group 4, PDL fibroblasts were cultured on a dentine surface pretreated with a combination of PDGF-BB and IGF-1. In group 5, PDL fibroblasts were cultured and allowed to attach on the TTC conditioned dentine surfaces. In groups 6 and 7, surface of dentine chips were conditioned with TTC and then were treated with PDGF-BB or IGF-1 respectively, followed by placement of PDL fibroblast and cultured. In group 8, dentine surfaces were conditioned with TTC and then pre-treated with a combination of PDGF-BB and IGF-1 before the fibroblasts were cultured. After 24 h of incubation, the media was removed and samples were fixed and processed for SEM at magnifications of x34, x750, x2000. Photographing and evaluation of samples was performed at x750 in which fibroblast adherence was measured by counting cells within a standard test area. The results of the non-TTC conditioned root surfaces demonstrated a significant increase in fibroblasts adherence in the PDGF-BB and combination PDGF-BB/IGF-I treatment groups (groups 2, 4) when compared to the control (group 1) as well as the TTC control (group 5). The combination of PDGF-BB/IGF-1 (group 4) did not significantly improve the adhesion of cells compared to PDGF-BB alone (group 2), but did significantly improve adhesion when compared to IGF-1 alone (group 3). There were no significant differences in cell morphology between the growth factor groups (groups 2, 3, 4) and control (group 1). In general, the cells demonstrated a flat, stellate-shaped morphology. The results of the TTC conditioned root surfaces, showed a statistically significant increase of cellular adherence in the PDGF-BB group (group 6) when compared to the TTC control (group 5), similar to the non-TTC group (group 2). However, the morphology of the cells in groups 5, 6, 7, and 8 demonstrated generally a rounded or oval shape with only an occasional cell exhibiting a flat form. In the experimental system of this study, the inclusion of PDGF-BB on the surface of dentine chips increased the number of adhering PDL cells, and the addition of TTC conditioning had little effect except to change the morp...

Within the limits of the present study, it can be concluded that PRF and PRGF platelet concentrate failed to augment clinical effects achieved with the xenograft alone in treating intrabony defects. Periodontal defects could not retain extraphysiologic levels of GF suggested to be associated with platelet concentrate.

The present study demonstrated enhanced clinical outcomes when using novel MPMs compared to OMs in guided tissue regeneration procedures. These results may be affected by the penetration of gingival CT contained stem cells and periosteal cells and their differentiation into components of the attachment apparatus.

To our knowledge, these results represent the first biologic evidence that D-PDLFs retain uniquely inflammatory phenotypes that could maintain localized destructive signals in periodontitis. The overexpression of proinflammatory cytokines by PDLFs could amplify local inflammation by the continuous triggering of immune responses. In addition, the location of these cells could be critical in the progression of the inflammatory front into the deeper tissues.

Within the limits of the present study, one can conclude that PM coverage of periodontal defects is associated with initial gingival crevicular fluid growth factor upregulation that could improve the clinical outcomes of guided tissue regeneration surgery.