title: Long-term cytotoxicity of orthodontic direct-bonding adhesives.
abstract: The purpose of this study was to examine the potential toxic effects of several orthodontic adhesives immediately after polymerization and at various time intervals up to 2 years postopolymerization by means of an in vitro overlay assay. Adhesive samples were incubated on tissue cultures containing an agar overlay with a vital dye (neutral red). Viable cells were stained red; nonviable cells were unstained. The circular pattern of nonviable cells demonstrated a zone of inhibition that was measured and compared. All materials tested showed cytotoxic effects immediately after polymerization and the toxic effect decreased with time postpolymerization. However, 2 years after initial polymerization, significant zones of inhibition indicating continued in vitro toxicity were still evident in all but one of the adhesives.
authors.affiliation: Department of Orthodontics, University of Maryland Dental School, Baltimore 21201.
authors.forename: R T
authors.initials: RT
authors.lastname: Tell
authors.forename: R J
authors.initials: RJ
authors.lastname: Sydiskis
authors.forename: R D
authors.initials: RD
authors.lastname: Isaacs
authors.forename: W M
authors.initials: WM
authors.lastname: Davidson
mesh_terms: D000269:Adhesives / Q000633:toxicity*; D000818:Animals; D002460:Cell Line; D002470:Cell Survival; D002522:Chlorocebus aethiops; D004396:Coloring Agents; D003188:Composite Resins / Q000633:toxicity*; D001840:Dental Bonding; D007668:Kidney; D008422:Materials Testing; D009967:Orthodontic Appliances; D011108:Polymers; D013997:Time Factors
chemical_list: D000269:Adhesives; D004396:Coloring Agents; D003188:Composite Resins; D011108:Polymers