A FLUORESCENT DYE METHOD FOR DEMONSTRATING LEAKAGE AROUND DENTAL RESTORATIONS.

摘要

This study was conducted to determine if the fluorescent dyes,rhodamine B,fluorescein and demethylchlortetracycline could demonstrate microleakage around dental restorations. A new simplified fluorescent technique for testing and scoring microleakage was presented. A total of 87class V cavities were prepared in 32bovine mandibular incisor teeth. The cavities were divided into four groups and restored with representative leaking and non-leaking fillings. The teeth were immersed in the test dyes for periods varying from five minutes to one hour. After drying,the teeth were sectioned with separating discs and viewed through a binocular microscope,under ultraviolet light. With one exception,the dyes satisfactorily showed marginal leakage of filling materials. The margins of the 24hour amalgam filling with no cavity liner showed great penetration with fluorescein and rhodamine B. In a second group of amalgams,cavity varnishes greatly reduced marginal leakage. All gutta percha restorations showed gross leakage. The fluorescent dyes tested did not show microleakage of zinc oxide eugenol restorations due to a 'quenching'of fluorescence. Sound enamel of bovine and human teeth was impermeable to the fluorescent dyes tested. Of the dyes tested,fluorescein and demethylchlortetracycline showed the greatest promise for future research. They are inexpensive,non-toxic in humans,and contrast sharply with the tooth's natural fluorescence.