ABSTRACT
Comparison was made of the apical microleakage of retrograde fillings with amalgam and with silver glass ionomer cements using a modified dye penetration method. Forty instrumented human teeth were divided into four groups. Each group was characterized by a different retrograde filling material or technique: Group 1--silver glass ionomer (SGI); group 2--SGI with previous acid wash of the cavity; group 3--SGI in a previously acid washed cavity, protected with varnish; and group 4--zinc-free amalgam. A paper cone for dye adsorption analysis was placed in contact with retrofill and the main canal was obturated with thermoplasticized gutta-percha. All teeth were coated, immersed in methylene blue dye, and evacuated to assure complete penetration of the dye in any possible void. Later the teeth were cleared and evaluated under stereomicroscope. Statistical analysis showed that group 1 had the least microleakage of all. In addition, the biocompatibility of the SGI and varnish was compared with that of amalgam using the 51Cr release evaluation method. The results showed that SGI and varnish were less cytotoxic than amalgam. It was concluded that SGI cement can be considered an alternative retrograde filling material.
Subject(s)
Cermet Cements , Dental Amalgam , Glass Ionomer Cements , Retrograde Obturation , Root Canal Filling Materials , Dental Leakage , Glass Ionomer Cements/toxicity , Humans , Materials Testing , Methylene BlueABSTRACT
An in vitro method for longitudinal evaluation of root canal sealers was developed and applied. A newly introduced cell culture chamber was used to evaluate the cytotoxic effects of test samples immediately after mixing and for an extended period of time thereafter. A ranking of the test materials, based on their cytotoxicity, was allowed by the method.
