title: MMPs activity and bond strength in deciduous dentine-resin bonded interfaces.
abstract: OBJECTIVE
  To determine effect of ageing on deciduous dentine-resin interfaces bond strength and the metalloproteinases (MMPs) activity at the hybrid layer compared to permanent dentine.
  
  
  METHODS
  Microtensile bond strength (MTBS) tests were performed in human deciduous and permanent dentine after 24h, 3 and 6 months using an etch and rinse adhesive. C-terminal telopeptide concentrations (ICTP) were calculated, in order to determine MMPs mediated collagen degradation at the hybrid layer.
  
  
  RESULTS
  The highest MMPs-mediated collagen degradation values occurred in phosphoric acid demineralized dentine, ICTP values were similar for deciduous and permanent dentine after 1 week. Resin infiltration decreased collagen degradation in both dentins and ICTP values were similar to those attained by for untreated dentine. In resin infiltrated and untreated dentine specimens collagen degradation was always higher for deciduous dentine. At 24h, MTBS was higher in permanent dentine. After ageing MTBS decreased and performed similarly in both dentins.
  
  
  CONCLUSIONS
  Higher collagenollytic activity is found in deciduous than in permanent dentine. At 24h, collagen cleavage by MMPs at the hybrid layer is higher in deciduous dentine leading to a lower MTBS.
  
  
  CONCLUSIONS
  The presence of resin monomers reduced collagen degradation when applied on demineralized dentine, but exerted protection was lower in deciduous dentine.
authors: Department of Dental Materials, School of Dentistry, University of Granada, 18071 Granada, Spain. rosorio@ugr.es
authors: Raquel
authors: R
authors: Osorio
authors: Monica
authors: M
authors: Yamauti
authors: María E
authors: ME
authors: Ruiz-Requena
authors: Manuel
authors: M
authors: Toledano
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003094:Collagen / Q000378:metabolism; D024042:Collagen Type I / Q000032:analysis; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003799:Dental Stress Analysis / Q000295:instrumentation; D003804:Dentin / Q000201:enzymology / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D006801:Humans; D055115:Light-Curing of Dental Adhesives / Q000379:methods; D020782:Matrix Metalloproteinases / Q000378:metabolism*; D010455:Peptides / Q000032:analysis; D010756:Phosphoric Acids / Q000737:chemistry; D012464:Saliva, Artificial / Q000737:chemistry; D013314:Stress, Mechanical; D013718:Tensile Strength; D013997:Time Factors; D017001:Tooth Demineralization / Q000503:physiopathology; D014094:Tooth, Deciduous / Q000201:enzymology / Q000648:ultrastructure*
chemical_list: D024042:Collagen Type I; D003188:Composite Resins; D017220:Dentin-Bonding Agents; D010455:Peptides; D010756:Phosphoric Acids; D012464:Saliva, Artificial; C511238:Single Bond Plus; C052929:collagen type I trimeric cross-linked peptide; D017438:Bisphenol A-Glycidyl Methacrylate; D003094:Collagen; C030242:phosphoric acid; D020782:Matrix Metalloproteinases