title: Attachment and proliferation of human osteoblast-like cells on guided bone regeneration (GBR) membranes in the absence or presence of nicotine: an in vitro study.
abstract: OBJECTIVE
  To compare in vitro the attachment and proliferation of human osteoblast-like cells (MG63) on tissue culture plates and guided bone regeneration (GBR) membranes in the absence or presence of nicotine.
  
  
  METHODS
  Membrane samples were fixed to wells and the cell number (CN) was counted after 24 hours (attachment assay) or 5 days (proliferation assay). The ratio of cell count (RCC) (CN at 5 days/CN at 24 hours) was calculated. The study had three parts: First, five different resorbable GBR membranes were compared (Resolut Adapt LT [RALT], Biocollagen [BC], Bio-Gide [BG], OsseoGuard [OG], and Demokritos Human Tissue Bank [DEM]). Next, cells were cultured on tissue culture plates with five different concentrations of nicotine. Finally, cells were cultured on the membrane that had demonstrated the highest RCC and CN in part 1 with four different concentrations of nicotine.
  
  
  RESULTS
  At 24 hours, BG showed the highest CN and OG showed the lowest CN. At 5 days, BG showed the highest CN. The order of RCC was BG > OG > DEM > RALT ~ BC. At 24 hours, lower nicotine concentrations (0.3 and 3 μg/mL) showed higher CNs versus the control, whereas CNs for high nicotine concentrations (30 and 300 μg/mL) were lower than for the control. CN at 5 days and RCC were lowest with 300 μg/mL nicotine. At 24 hours and 5 days, all differences among wells with membrane were statistically insignificant. Nevertheless, CN at 5 days and RCC were highest with the lowest nicotine concentration (3 μg/mL) and lowest with high concentrations.
  
  
  CONCLUSIONS
  Membrane materials influence attachment and proliferation of bone cells and, therefore, could affect the outcomes of GBR. On both tissue culture plates and membranes, there is a tendency toward a biphasic effect of nicotine, with stimulatory effects at low concentrations and inhibitory effects at high concentrations.
authors.affiliation: Department of Periodontology, University of Athens, Greece.
authors.forename: Konstantinos A
authors.initials: KA
authors.lastname: Papaioannou
authors.forename: Cleopatra E
authors.initials: CE
authors.lastname: Markopoulou
authors.forename: Vassiliki
authors.initials: V
authors.lastname: Gioni
authors.forename: Anastasios A
authors.initials: AA
authors.lastname: Mamalis
authors.forename: Helen N
authors.initials: HN
authors.lastname: Vayouraki
authors.forename: Dimitris
authors.initials: D
authors.lastname: Kletsas
authors.forename: Ioannis A
authors.initials: IA
authors.lastname: Vrotsos
mesh_terms: D020341:Absorbable Implants / Q000145:classification; D001672:Biocompatible Materials / Q000737:chemistry*; D002448:Cell Adhesion / Q000187:drug effects; D018929:Cell Culture Techniques; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D016557:Guided Tissue Regeneration, Periodontal / Q000295:instrumentation; D006801:Humans; D008137:Longitudinal Studies; D008567:Membranes, Artificial; D009538:Nicotine / Q000009:adverse effects*; D018722:Nicotinic Agonists / Q000009:adverse effects; D010006:Osteoblasts / Q000187:drug effects*; D012907:Smoking / Q000009:adverse effects*; D018709:Statistics, Nonparametric
chemical_list: D001672:Biocompatible Materials; D008567:Membranes, Artificial; D018722:Nicotinic Agonists; D009538:Nicotine