Color stability of repairs on bis-acryl resin submitted to thermal aging and immersion in beverages.

OBJECTIVE: Defects/bubbles can occur during the manufacture of bis-acryl resin provisional restorations, requiring repair or new prosthesis. This study evaluated the color stability of bis-acryl resin specimens repaired, aging, and immersioned in beverages. MATERIAL AND METHODS: Eighty disks were made of bis-acryl resin. Twenty disks were not repaired (BCR), 20 disks were repaired with the same bis-acryl resin (BCR-BCR), 20 disks were repaired with flowable resin (BCR-FR), and 20 disks received an adhesive layer prior to flowable resin repair (BCR-AFR). Coordinates L*a*b* were obtained. Ten disks from each group were thermocycled (5000 cycles) and the others were immersed in coffee with sugar (n = 5) and cola-based soft drinks (n = 5) for 7 days. Color, lightness, chroma, and hue differences were calculated by the CIEDE2000 formula, analyzed by two-way analysis of variance. Multiple comparisons were made with the Tukey's HSD test (α = .05). RESULTS: BCR-FR group presented the highest color differences (5.6) between groups repaired (P < .001). BCR-BCR group showed the smallest color differences (0.9) after aging (P = .003), but the greatest variation between T0 and T1 (about 1 ΔE). BCR-ARF immersed in coffee showed the greatest color differences (20.6) (P < .001). CONCLUSIONS: Aging and immersion altered the colorimetric behavior of repairs, especially after the use of coffee. CLINICAL IMPLICATIONS: Repairs are indicated when defects and bubbles are present in the surface of the bis-acryl resin provisional restorations after its manufacture. However, they may present noticeable color changes, especially when the use of coffee is frequent.

Zonas mortas da cóclea e amplificação: avaliação de resultados / Dead cochlear regions and amplification: outcome assesment

Este estudo teve como objetivo avaliar os resultados obtidos em um questionário de auto-avaliação aplicado em indivíduos com zonas mortas na cóclea usuários de aparelhos de amplificação sonora individual (AASI). Foi aplicado o Questionário Internacional - Aparelho de Amplificação Sonora Individual (QI-AASI) em 29 indivíduos com perda auditiva neurossensorial leve a profunda descendente, usuários de AASI, que apresentaram resultados indicativos de zona morta no teste TEN. A faixa etária variou entre 13 re 83 anos (média = 48 anos). Os resultados demonstraram satisfação dos sujeitos com seus AASI e, portanto, a presença de zona morta indicada pelo TEN ainda não é suficiente para definir a conduta quanto à prescrição do ganho acústico do AASI