title: Nanoionomer: evaluation of microleakage.
abstract: BACKGROUND
  Glass ionomer cements are widely used in pediatric practice due to their advantage of fluoride release and chemical bond to tooth structure. Adherence of the restorative material to the cavity walls is one of the most important characteristic for it to be proven as an ideal material as it prevents microleakage.
  
  
  OBJECTIVE
  This study was aimed at evaluating the microleakage of nanofilled resin-modified glass ionomer cement compared with the conventional and resin-modified glass ionomer cements.
  
  
  METHODS
  Standard class V cavities of size 3 mm x 2 mm x 2 mm were made on a total of 30 extracted teeth and restored with the conventional glass ionomer, resin-modified glass ionomer or nanoionomer. After thermocycling, teeth were immersed in 0.5% methylene blue dye for 24 h. They were then sectioned buccolingually. Microleakage was assessed for the occlusal and gingival walls using a compound microscope by two examiners independently.
  
  
  RESULTS
  Nanoionomer demonstrated the least microleakage, with a mean score of 1.3, compared with the resin-modified glass ionomer (score of 3.2) and conventional glass ionomer cement (score 2.6).
  
  
  CONCLUSIONS
  Nanoionomer exhibited adequate resistance to microleakage and thus may prove better than conventional or resin-modified glass ionomers.
authors.affiliation: Department of Paedodontics and Preventive Dentistry, Manipal College of Dental Sciences, Manipal University, Mangalore, India.
authors.forename: S
authors.initials: S
authors.lastname: Upadhyay
authors.forename: A
authors.initials: A
authors.lastname: Rao
mesh_terms: D004396:Coloring Agents; D001840:Dental Bonding; D003737:Dental Cavity Preparation / Q000145:classification; D003763:Dental Leakage / Q000145:classification*; D003793:Dental Restoration, Permanent; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D008751:Methylene Blue; D049329:Nanostructures / Q000737:chemistry*; D019279:Resin Cements / Q000737:chemistry; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors
chemical_list: D004396:Coloring Agents; D005899:Glass Ionomer Cements; D019279:Resin Cements; D008751:Methylene Blue