title: Prevention of toothbrushing abrasion of acid-softened enamel by CO(2) laser irradiation.
abstract: OBJECTIVE
  The aim of the present study was to evaluate the effect of CO(2) laser irradiation (10.6μm) at 0.3J/cm(2) (0.5μs; 226Hz) on the resistance of softened enamel to toothbrushing abrasion, in vitro.
  
  
  METHODS
  Sixty human enamel samples were obtained, polished with silicon carbide papers and randomly divided into five groups (n=12), receiving 5 different surface treatments: laser irradiation (L), fluoride (AmF/NaF gel) application (F), laser prior to fluoride (LF), fluoride prior to laser (FL), non-treated control (C). After surface treatment they were submitted to a 25-day erosive-abrasive cycle in 100ml sprite light (90s) and brushed twice daily with an electric toothbrush. Between the demineralization periods samples were immersed in supersaturated mineral solution. At the end of the experiments enamel surface loss was determined using a contact profilometer and morphological analysis was performed using scanning electron microscopy (SEM). For SEM analysis of demineralization pattern, cross-sectional cuts of cycled samples were prepared. The data were statistically analysed by one-way ANOVA model with subsequent pairwise comparison of treatments.
  
  
  RESULTS
  Abrasive surface loss was significantly lower in all laser groups compared to both control and fluoride groups (p<0.0001 in all cases). Amongst the laser groups no significant difference was observed. Softened enamel layer underneath lesions was less pronounced in laser-irradiated samples.
  
  
  CONCLUSIONS
  Irradiation of dental enamel with a CO(2) laser at 0.3J/cm(2) (5μs, 226Hz) either alone or in combination with amine fluoride gel significantly decreases toothbrushing abrasion of softened-enamel, in vitro.
authors: Department of Operative Dentistry, Periodontology and Preventive Dentistry (ZPP), RWTH Aachen University, Germany. mestevesoliveira@ukaachen.de
authors: M
authors: M
authors: Esteves-Oliveira
authors: C
authors: C
authors: Pasaporti
authors: N
authors: N
authors: Heussen
authors: C P
authors: CP
authors: Eduardo
authors: F
authors: F
authors: Lampert
authors: C
authors: C
authors: Apel
mesh_terms: D002327:Cariostatic Agents / Q000627:therapeutic use; D019343:Citric Acid / Q000494:pharmacology; D003743:Dental Enamel / Q000187:drug effects / Q000473:pathology / Q000528:radiation effects*; D003747:Dental Enamel Solubility / Q000187:drug effects / Q000528:radiation effects; D003959:Diamines / Q000627:therapeutic use; D017886:Durapatite / Q000737:chemistry; D005459:Fluorides / Q000627:therapeutic use; D006801:Humans; D054020:Lasers, Gas / Q000627:therapeutic use*; D028022:Low-Level Light Therapy / Q000379:methods; D008855:Microscopy, Electron, Scanning; D011829:Radiation Dosage; D012969:Sodium Fluoride / Q000627:therapeutic use; D013997:Time Factors; D014072:Tooth Abrasion / Q000517:prevention & control*; D014077:Tooth Erosion / Q000473:pathology / Q000517:prevention & control*; D014089:Tooth Remineralization; D014099:Toothbrushing / Q000009:adverse effects* / Q000295:instrumentation
chemical_list: D002327:Cariostatic Agents; D003959:Diamines; D019343:Citric Acid; C495399:Olaflur; D012969:Sodium Fluoride; D017886:Durapatite; D005459:Fluorides