Randomized clinical trial of four adhesion strategies in posterior restorations-18-month results.

Purpose: To evaluate the 18-month clinical performance of four adhesive strategies in posterior composite restorations placed in private practice.

Materials And Methods: Upon approval by an institutional review board, 144 restorations were inserted in 45 subjects (average age = 32.6) to treat caries lesions or to replace existing restorations in vital molars and premolars.

Colour stability and opacity of resin cements and flowable composites for ceramic veneer luting after accelerated ageing.

Objectives: Colour changes of the luting material can become clinically visible affecting the aesthetic appearance of thin ceramic laminates. The aim of this in vitro study was to evaluate the colour stability and opacity of light- and dual-cured resin cements and flowable composites after accelerated ageing.

Methods: The luting agents were bonded (0.

Fracture loads of all-ceramic crowns under wet and dry fatigue conditions.

Purpose: The aim of this study was to test the hypothesis that fracture loads of fatigued dental ceramic crowns are affected by testing environment and luting cement.

Materials And Methods: One hundred and eighty crowns were prepared from bovine teeth using a lathe. Ceramic crowns were prepared from three types of ceramic systems: an alumina-infiltrated ceramic, a lithia-disilicate-based glass ceramic, and a leucite-reinforced ceramic.

Impact of refrigeration on the surface hardness of hybrid and microfilled composite resins.

This in vitro study evaluated the Knoop hardness of the composite resins Charisma (C) and Durafill VS (D) polymerized in 3 different conditions: at room temperature (A) (23 +/- 1 degrees C); refrigerated at 4 +/- 1 degrees C and immediately photo-activated after removal from the refrigerator (0); and, refrigerated at 4 +/- 1 degrees C and photo-activated after a bench time of 15 min at room temperature (15). One hundred and twenty specimens (4 mm diameter and 2 mm depth) were made using a stainless steel mold and following manufacturer's instructions. All specimens were tested immediately after polymerization (I) and after 7 days of water storage in the dark at room temperature (7d).

Sorption and solubility of composites cured with quartz-tungsten halogen and light emitting diode light-curing units.

Aim: The objective of this study was to evaluate the effect of light polymerization on water sorption and solubility of hybrid composites.

Methods And Materials: Three composite resins were used to make discs cured with either quartz-tungsten halogen (QTH) or light emitting diode (LED) curing units. The specimens were stored in a desiccator at 37 degrees C and weighted to a constant mass, then immersed in deionized water for different periods of time, and reconditioned until achieving a constant mass.

Influence of curing tip distance on resin composite Knoop hardness number, using three different light curing units.

This in vitro study evaluated the influence of curing tip distance on the Knoop Hardness Number (KHN) of a resin composite when using three different light curing units: (1) a halogen light (XL 1500 curing unit-3M), (2) a "softstart-polymerization" (Elipar Trilight curing in an exponential mode-ESPE) and (3) a PAC (Apolo 95E curing unit-DMD). The resin composite, Filtek Z250 (3M), was cured by these curing units at three light-tip distances from the resin composite: 0 mm, 6 mm and 12 mm. The resin composite specimens were flattened to their middle portion and submitted to 18 KHN measurements perspecimen.