title: Hydrodynamic flow through loading and in vitro secondary caries development.
abstract: This in vitro study investigated the effect of hydrodynamic flow through mechanical loading on development of secondary caries lesions. Forty-eight bovine tooth specimens (enamel and dentin; sizes 3.2 x 3.2 x 2.0 mm) were restored with resin-composite on polystyrene bars; 18 samples were bonded, and 30 were not bonded. Specimens were suspended in a lactic acid solution (pH = 5; 14 days) in a modified brushing machine, and artificial caries lesions were formed. During caries development, specimens were mechanically loaded at the surface of the polystyrene bar, bent so that the tooth- composite interfaces were subjected to opening forces (16x/min). Loads applied were either none (Control Bonded, CB, n = 6; and Control Non-bonded, CNB, n = 6), 200 gr (NB200, n = 12), or 350 gr (NB350 and B350, both n = 12). Before and after caries development, specimens were imaged with transverse wavelength-independent microradiography (T-WIM), and lesion depth (LD) and mineral loss (ML) were calculated at 4 different locations. An independent t test was used to compare the LD and ML at the 4 different locations. A statistically significant effect of the level of loading (comparing groups NB200 and NB350) and of bonding (comparing groups NB350 and B350) could be observed, with a higher load and absence of bonding leading to more advanced lesions.
authors: College of Dental Sciences, Department of Preventive and Restorative Dentistry, Radboud University Nijmegen Medical Centre, P.O. Box 9101, NL 6500 HB Nijmegen, The Netherlands. n.kuper@dent.umcn.nl
authors: N K
authors: NK
authors: Kuper
authors: N J M
authors: NJ
authors: Opdam
authors: E M
authors: EM
authors: Bronkhorst
authors: J L
authors: JL
authors: Ruben
authors: M C D N J M
authors: MC
authors: Huysmans
mesh_terms: D000818:Animals; D002417:Cattle; D003188:Composite Resins / Q000627:therapeutic use*; D001840:Dental Bonding / Q000379:methods*; D003731:Dental Caries / Q000209:etiology / Q000473:pathology* / Q000628:therapy; D003763:Dental Leakage / Q000150:complications*; D018772:Dental Marginal Adaptation; D003793:Dental Restoration, Permanent; D003799:Dental Stress Analysis; D057446:Hydrodynamics; D013314:Stress, Mechanical
chemical_list: D003188:Composite Resins