Marginal Adaptation and Quality of Interfaces in Lithium Disilicate Crowns - Influence of Manufacturing and Cementation Techniques.

Purpose: To evaluate the cement line thickness and the interface quality in milled or injected lithium disilicate ceramic restorations and their influence on marginal adaptation using different cement types and different adhesive cementation techniques.

Methods And Materials: Sixty-four bovine teeth were prepared for full crown restoration (7.0±0.

Effects of preheating and precooling on the hardness and shrinkage of a composite resin cured with QTH and LED.

The aim of this study was to evaluate in vitro the hardness and shrinkage of a pre-cooled or preheated hybrid composite resin cured by a quartz-tungsten-halogen light (QTH) and light-emitting diode (LED) curing units. The temperature on the tip of the devices was also investigated. Specimens of Charisma resin composite were produced with a metal mold kept under 37°C.

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.