Examination of esthetic improvement and surface alteration following microabrasion in fluorotic human incisors in vivo.

Improvement of appearance and alteration in surface enamel was evaluated following microabrasion of teeth with differing degrees of fluorosis stain in vivo. Eighty-two fluorotic permanent maxillary central incisors from 41 patients were divided into categories of mild (32), moderate (30), and severe (20). Teeth received 30-sec applications of PREMA until no stain remained or for a maximum of 10 min of treatment. Ten teeth needed only 5 min of treatment. All others received the maximum. Standardized intraoral photographs and duplicate polysiloxane impressions were taken prior to treatment, after 5 and 10 min of treatment, and at least 4 days after treatment. Slides were randomized and viewed independently by two standardized observers and rated for area of white spot lesions (WS), stain amount (SA), and stain intensity (SI). The Wilcoxon's signed rank test indicated a significant difference in the area of WS (P < 0.05) and SA and SI (P < 0.005) from pretreatment to successive ratings. Kruskal-Wallis analysis revealed significant differences among the three severity groups for amount of WS, SA, and SI (P < 0.005). Mildly stained teeth had the best esthetic result, moderately stained teeth improved but continued to demonstrate WS and staining, and severely stained teeth showed some improvement, but more than 50% of the surface had WS and > 25% of the surface was stained. SEMs at 10X magnification were made of the models and randomly rated for type, depth, description, and area of surface defects by the two observers. Mild teeth showed no significant changes from pretreatment to 10 min of treatment. Moderate and severe teeth showed no significant change in type and depth of defects from pretreatment to 10 min of treatment but were significantly worse in description and area of defects. Despite esthetic improvement in all groups, moderate and severe teeth showed more defective surfaces following microabrasion. This technique can only be recommended as definitive treatment for teeth with mild fluorosis.

Comparison of manually and mechanically mixed glass ionomers.

Two mechanically mixed glass ionomer restorative materials (Ketac-Fil and Fuji Cap II) were compared with two manually mixed products (Chelon-Fil and Fuji Type II). One manually mixed material was substantially weaker than the others in bond strength tests. No significant differences in microleakage were found among the materials.