Aim: Chemical decontamination increases the availability of bone grafts; however, it is unclear whether antiseptic processing changes the biological activity of bone.
Materials and Methods:Bone chips were incubated with 4 different antiseptic solutions including (1) povidone-iodine (0.5%), (2) chlorhexidine diguluconate (0.2%), (3) hydrogen peroxide (1%) and (4) sodium hypochlorite (0.25%). After 10 minutes of incubation, changes in the capacity of the boneconditioned medium to modulate gene expression of gingival fibroblasts was investigated.Results: Conditioned medium obtained from freshly prepared bone chips increased the expression of TGF-β target genes interleukin 11 (IL11), proteoglycan4 (PRG4), NADPH oxidase 4 (NOX4), and decreased the expression of adrenomedullin (ADM), and pentraxin 3 (PTX3) in gingival fibroblasts.Incubation of bone chips with 0.2% chlorhexidine, followed by vigorously washing resulted in a bone-
Accepted ArticleThis article is protected by copyright. All rights reserved.conditioned medium with even higher expression of IL11, PRG4, and NOX4. These findings were also found with a decrease in cell viability and an activation of apoptosis signaling. Chlorhexidine alone, at low concentrations, increased IL11, PRG4 and NOX4 expression, independent of the TGF-β receptor I kinase activity. In contrast, 0.25% sodium hypochlorite almost entirely abolished the activity of boneconditioned medium, while the other two antiseptic solutions, 1% hydrogen peroxide and 0.5% povidone-iodine, had relatively no impact, respectively.
Conclusion:These in vitro findings demonstrate that incubation of bone chips with chlorhexidine differentially affects the activity of the respective bone-conditioned medium compared to the other antiseptic solutions. The data further suggest that the main effects are caused by chlorhexidine remaining in the bone-conditioned medium after repeated washing of the bone chips.
Clinical RelevanceScientific rationale for study: Antiseptic solutions are commonly used for a variety of procedures in the dental field including decontamination of bone grafts and irrigation of bone defects. The impact of different antiseptic solutions on the biological properties of bone remains unclear.Principal findings: Conditioned media from bone exposed to chlorhexidine significantly increased the gene expression of periodontal fibroblasts TGF-β target genes when compared to bone exposed to povidone-iodine and hydrogen peroxide. Furthermore, it was found that sodium hypochlorite almost entirely abolished the activity of the bone-conditioned medium.
Practical implication:The findings from this in vitro study demonstrate that antiseptic solution might considerably affect bone activity by modulating gene expression following rinsing. Chlorhexidine performed significantly better than the other modalities tested.