title: Assessment of micronucleus frequency in normal oral mucosa of patients exposed to carcinogens.
abstract: OBJECTIVE
  To assess the presence of micronuclei in exfoliated oral mucosal cells collected from 3 anatomic sites in patients exposed to tobacco and alcohol.
  
  
  METHODS
  Smears were prepared with normal oral mucosal cells obtained from the lower lip, tongue border and floor of the mouth of 21 controls, 28 tobacco users and 19 tobacco/alcohol users. Slides were stained with Feulgen stain for quantification of micronucleated cells, karyorrhexis and "broken eggs."
  
  
  RESULTS
  The groups were similar in terms of the mean number of micronucleated cells and cells undergoing karyorrhexis. In the comparison of anatomic sites, the mean number of cells undergoing karyorrhexis was higher on the lower lip than on the tongue border or floor of the mouth (all groups). A significantly higher number of broken eggs was observed in the control group when compared to the tobacco and tobacco/alcohol groups at all anatomic sites.
  
  
  CONCLUSIONS
  The higher number of broken eggs in patients not exposed to tobacco and/or alcohol suggests that this nuclear alteration may be associated with DNA repair or a healthy mucosa. A trend toward an increased number of micronucleated cells was observed for tobacco and/or alcohol users at all anatomic sites.
authors.affiliation: Graduate Program in Dentistry, School of Dentistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Paula Luce
authors.initials: PL
authors.lastname: Bohrer
authors.forename: Manoel Sant'Ana
authors.initials: MS
authors.lastname: Filho
authors.forename: Ricardo Losekan
authors.initials: RL
authors.lastname: Paiva
authors.forename: Isabel Lauxen
authors.initials: IL
authors.lastname: da Silva
authors.forename: Pantelis Varvaki
authors.initials: PV
authors.lastname: Rados
mesh_terms: D000328:Adult; D000368:Aged; D000434:Alcoholic Beverages / Q000633:toxicity*; D001938:Brazil; D002273:Carcinogens / Q000633:toxicity*; D006801:Humans; D008297:Male; D015162:Micronucleus Tests; D008875:Middle Aged; D009061:Mouth Mucosa / Q000187:drug effects* / Q000648:ultrastructure; D012907:Smoking
chemical_list: D002273:Carcinogens