Effects of nicotine on the strength of attachment of gingival fibroblasts to glass and non-diseased human root surfaces

Background: The aim of this study was to evaluate the effect of nicotine on the strength of attachment of human gingival fibroblast cells to glass and non-diseased human root surfaces. Methods: Human gingival fibroblast cells (HGF) were trypsinized, suspended in RPMI 1640 medium, and incubated with autoclaved human root and glass sec tions and nicotine (NIC) concentrations of 0 (control), 25, 50, and 100 ng/ ml for 1 week. HGF attached and grew on glass and root surfaces for 4 weeks at all NIC concentrations. HGF cultures were subjected to a rotary shaker machine for 30 minutes to test the strength of attachment of these cells at 100, 150, and 200 rpm. The root and glass sections were examined at 48 hou rs by light microscopy. Results: Control groups exhibited a monolayer of long, spindle-shaped fibro blasts with a parallel alignment and minimal overlapping. With a concentrat ion of NIC of 50 or 100 ng/ml as well as with increasing "speeds," the numb er of cells attached to these surfaces decreased dramatically. When 200 rpm was used for both groups at all NIC concentrations, very few HGF remained attached to these surfaces. Conclusions: This study showed that the nature of cell attachment to either glass or root surfaces is altered by nicotine, and marked detachment was n oted when nicotine exposure was coupled with vigorous agitation at differen t rpm. Marked detachment noted in all specimens at 200 rpm indicates that t his speed is excessive for use in subsequent experimentation.