Abstract
The adhesive bridge has many advantages and is considered suitable for the replacement of missing anterior teeth in the adolescent patient.
The purpose of this study was to investigate the metal surface conditioning to improve the adhesive strength for the lingual plate of the adhesive bridge.
The surfaces of nickel-chrome nonpresious ceramic alloy “Cyclon G” (Nihon Shiken Co. ) were polished with #220 Emery paper. Six specimens were sandblasted, using 25 micron alminium oxide perticle. Sixty cases were etched from 5 minutes to 60 minutes, using 60% nitric acid,36% hydrochloric acid,60% sulfuric acid and aqua regia. These specimens were washed and dried, then observed through a scanning electron microscope.
The sandblasted metal surfaces showed minute irregularity and scarcely any undercuts. The surfaces processed using nitric acid, hydrochloric acid and sulfuric acid did not show any obvious change, while the surfaces processed using aqua regia showed obvious irregularity and undercuts which are useful for retention of the lingual plate of the adhesive bridge.
