title: [Study on composition of plaque fluid in individuals with no oral hygiene].
abstract: OBJECTIVE
  To study the change of composition in long-term plaque fluid after sucrose rinse and the cariogenicity of plaque.
  
  
  METHODS
  43 subjects, who had no regular oral hygiene and no tooth brushing at least for one year, were selected. According to their caries status, 27 as caries-free group and 16 as caries-positive group. Plaque were obtained before and at 7 minutes after a 10% sucrose rinse. Additionally, plaque samples of 15 and 30 minutes after sucrose rinse from 11 subjects were collected. The pH value and the concentrations of organic acids and inorganic ions in plaque fluid were measured.
  
  
  RESULTS
  At 7 minutes after sucrose rinse, pH and the concentration of ammonium were significantly decreased, and the concentrations of lactic acid and formic acid were significantly increased. All these changes were similar to those of short-term plaque. No significant difference with any single component of plaque fluid was found between caries-free group and caries-positive group, neither before sucrose rinse nor after sucrose rinse.
  
  
  CONCLUSIONS
  Changes of the composition in the plaque fluid were basically similar between long-term and short-term plaque, but single component in plaque fluid could not reflect the cariogenicity of plaque.
authors.affiliation: Department of Stomatology, Second Peoples Hospital of Guangzhou, Guangzhou 510260, China.
authors.forename: D
authors.initials: D
authors.lastname: Deng
authors.forename: X
authors.initials: X
authors.lastname: Gao
authors.forename: Y
authors.initials: Y
authors.lastname: Shao
mesh_terms: D000328:Adult; D002118:Calcium / Q000378:metabolism; D003773:Dental Plaque / Q000737:chemistry*; D005122:Exudates and Transudates / Q000737:chemistry / Q000187:drug effects; D005561:Formates / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000378:metabolism; D008274:Magnesium / Q000378:metabolism; D009067:Mouthwashes / Q000494:pharmacology; D009910:Oral Hygiene; D011188:Potassium / Q000378:metabolism; D000644:Quaternary Ammonium Compounds / Q000378:metabolism; D012964:Sodium / Q000378:metabolism; D013395:Sucrose / Q000494:pharmacology
chemical_list: D005561:Formates; D009067:Mouthwashes; D000644:Quaternary Ammonium Compounds; C030544:formic acid; D019344:Lactic Acid; D013395:Sucrose; D012964:Sodium; D008274:Magnesium; D011188:Potassium; D002118:Calcium