Wear of resin-modified glass ionomers: an in vitro study.

The purpose of this study was to evaluate the wear resistance and clinical applicability of resin-modified glass ionomer cements as restorative or fissure-sealing materials. The in vitro wear of resin-modified glass ionomers was compared to conventional glass ionomers, a resin-based sealant, and a composite resin. A three-body wear test (enamel block--polymethylmethacrylate powder--experimental dental material) was performed by 20,000 cycles with a load of 4 kgf/cm2.

Early loss of pit and fissure sealant: a clinical and SEM study.

The rate of early loss of preventive resin restoration and single application of pit and fissure sealant was determined by a clinical survey. The rate of partial and complete sealant loss on the observed surfaces was 14.4% (43/299) at the 3-month recall, with a further loss of 7.

In vitro marginal leakage of Class II composite resin restorations by thermal cycling.

In vitro marginal leakage on class II composite resin restorations by thermal stress was investigated at the cervical, proximal, bucco-lingual, and mesio-distal margins of extracted human premolars. The composite materials used in this study were: (1) Occlusin with Bonding Agent(a), (2) Palfique Light-S with Light Bondb, (3) P-50 with Dentin Primer & Scotchbond 2c, and (4) P-50 with Vitrabond and Scotchbond 2c. Those four groups were representatives of a (l) conventional bonding agent, (2) hydrophilic bonding agent, (3) dentin priming or conditioning agent with a hydrophilic bonding agent, and (4) glass ionomer cement used for a sandwich technique.

[An in vitro study of wear and marginal fracture of posterior composite resins].

The collision-and-abrasion test was performed to reproduce the change of the surface structures of posterior composite resins by the stress of mastication and occlusion. Also the effect of the stress on wear and marginal fracture of composites was estimated qualitatively and quantitatively between the cavities with round bevel, straight bevel and butt joint. Extracted human posterior teeth were used as materials, and round or straight bevels were prepared along the margin of the standardized cavities using the bevel-preparing burs which had been designed by us.