title: Prophylactic agents and bacterial adherence to titanium.
abstract: OBJECTIVE
  An evaluation was made of surface alterations of commercially pure titanium and Ti6Al4V alloy caused by fluoride at the concentration present in dentifrices and oral mouth washes (1500 ppm), and by prophylactic use of airborne particle abrasion with bicarbonate of soda.
  
  
  METHODS
  For each material, 60 pre-fabricated disk-shaped test specimens with industrial metallographic finish, measuring 5 mm in diameter and 3 mm thick, were divided into four groups, according to the storage solutions: artificial saliva pH 7.0 (G1), fluoridated artificial saliva pH 5.5 (G2), airborne particle abrasion with bicarbonate of sodium (G3), airborne particle abrasion with bicarbonate of sodium followed by storage in fluoridated artificial saliva (G4). The surface roughness (Ra) was measured with a profilometer, before and after the storage periods. Afterwards, the test specimens were submitted to Streptococcus mutans adherence.
  
  
  RESULTS
  A statistically significant reduction in surface roughness was observed in commercially pure titanium in G1, G4 and in Ti6Al4V alloy, G1, G2, G4, and no statistically significant reduction in G3.
  
  
  CONCLUSIONS
  With a mean initial roughness surface of Ra=0.2 μm, fluoride promoted homogenization. Microscopy images confirmed these results. In the groups without significant homogenization, S. mutans adherence was greater, whereas it was lower in the groups in which the test specimens were stored previously in fluoridated saliva.
  
  
  CONCLUSIONS
  The greater homogenization that occurred, as well as the antimicrobial effect of fluoride, proved that bacterial adherence and effects of fluoride were both dependent on the roughness of the surface topography.
authors.affiliation: Dental Prosthetic Department, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil. re.nunesb@gmail.com
authors.forename: Renata Nunes
authors.initials: RN
authors.lastname: Barros
authors.forename: Cresus Vinícius Depes
authors.initials: CV
authors.lastname: de Gouvêa
mesh_terms: D000497:Alloys; D001422:Bacterial Adhesion / Q000502:physiology*; D002327:Cariostatic Agents / Q000008:administration & dosage / Q000737:chemistry*; D003722:Dental Alloys / Q000737:chemistry*; D045662:Dental Etching / Q000379:methods; D003764:Dental Materials / Q000737:chemistry*; D005459:Fluorides / Q000008:administration & dosage / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D009067:Mouthwashes / Q000008:administration & dosage; D012464:Saliva, Artificial / Q000737:chemistry; D017693:Sodium Bicarbonate / Q000737:chemistry*; D013295:Streptococcus mutans / Q000502:physiology; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D014100:Toothpastes / Q000008:administration & dosage
chemical_list: D000497:Alloys; D002327:Cariostatic Agents; D003722:Dental Alloys; D003764:Dental Materials; D009067:Mouthwashes; D012464:Saliva, Artificial; D014100:Toothpastes; C031462:titanium alloy (TiAl6V4); D017693:Sodium Bicarbonate; D014025:Titanium; D005459:Fluorides