title: Microhardness evaluation of enamel adjacent to an improved GIC sealant after different enamel pre-treatment procedures.
abstract: OBJECTIVE
  This in vitro study was carried out to evaluate the microhardness of enamel adjacent to a glass ionomer cement (GIC) with high fluoride content used as a sealant (Fuji Triage, GC Corp., Japan) after laser, bur or air abrasion treatment procedures.
  
  
  METHODS
  
  
  
  METHODS
  200 freshly extracted non-carious human molars were divided into 10 experimental groups according to the enamel pre-treatment method: A air abrasion (Mach 4.1 Kreativ Inc., USA); AP, Air abrasion + conditioning with 20% polyacrylic acid (GC cavity conditioner); L, Er,Cr:YSGG laser application (Waterlase, Biolase Technology, Inc., San Clemente, USA); LP, Er,Cr:YSGG laser application and fissure conditioning; B, ameloplasty carried out with a diamond bur especially designed for preparing fissures (Komet #8833); BP, ameloplasty + fissure conditioning; P, application of 20% polyacrylic acid and all fissures sealed with GIC; C, no fissure treatment, the material was applied directly to the fissures (control); R, application of 37% orthophosphoric acid and fissures sealed with a resin-based sealant (Fissurit; Voco, Germany) (control); N, no treatment (control). Half of each group of teeth were left in artificial saliva for one month and the rest for three months. The teeth were then sectioned and microhardness was measured using a Vickers test apparatus. Kruskal-Wallis, Mann-Whitney U and Dunn's multiple comparison tests were carried out (5% significance).
  
  
  RESULTS
  After one month results regarding hardness at the base and lateral walls of fissures were significantly higher in groups A, AP, L, LP, B, BP, P and C than in groups R and N (p<0.01), but no difference was seen between the treatment procedures. The results after three months produced similar findings with evenly increased values for all groups.
  
  
  CONCLUSIONS
  The results of this study showed that the tested GIC with a higher fluoride content seemed to improve the enamel hardness of the fissure enamel and could be regarded as an alternative material in cases where resin sealant applications are questionable.
authors.affiliation: Department of Pediatric Dentistry, Dentistry Faculty, Marmara University, Turkey.
authors.forename: E
authors.initials: E
authors.lastname: Haznedaroglu
authors.affiliation: Department of Biomaterials, Biomedical Engineering, Namik Kemal University, Turkey.
authors.forename: S
authors.initials: S
authors.lastname: Sozkes
authors.affiliation: Department of Pediatric Dentistry, Dentistry Faculty, Marmara University, Turkey.
authors.forename: A R
authors.initials: AR
authors.lastname: Mentes
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D000180:Acrylic Resins / Q000737:chemistry; D020906:Air Abrasion, Dental / Q000379:methods; D000537:Aluminum Oxide / Q000737:chemistry; D002327:Cariostatic Agents / Q000494:pharmacology; D003737:Dental Cavity Preparation / Q000295:instrumentation; D003743:Dental Enamel / Q000033:anatomy & histology* / Q000187:drug effects / Q000528:radiation effects; D045662:Dental Etching / Q000379:methods*; D005459:Fluorides / Q000494:pharmacology; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006244:Hardness; D006801:Humans; D053844:Lasers, Solid-State / Q000627:therapeutic use; D010756:Phosphoric Acids / Q000737:chemistry; D010895:Pit and Fissure Sealants / Q000494:pharmacology; D012464:Saliva, Artificial / Q000737:chemistry
chemical_list: D000180:Acrylic Resins; D002327:Cariostatic Agents; D005899:Glass Ionomer Cements; D010756:Phosphoric Acids; D010895:Pit and Fissure Sealants; D012464:Saliva, Artificial; C006903:carbopol 940; C030242:phosphoric acid; D000537:Aluminum Oxide; D005459:Fluorides