Influence of eugenol-containing temporary restorations on the microleakage of total-etch and self-etching adhesive systems / Influência de restaurações temporárias contendo eugenol na microinfiltração de sistemas adesivos convencional e autocondicionante

Purpose: This in vitro study evaluated the influence of zinc oxide-eugenol temporary cement (ZOE-TC) on the sealing ability of composite restorations using two adhesive systems. Methods: Standard Class V cavities were prepared in 20 bovine incisors and restored with either ZOE-TC (IRM®) or eugenol-free cement (Cavit®) (n=10/temporary cement type). After 7 days, five teeth per material group were restored using Single Bond® (SB) and five using Adper Prompt® (AP). The cavities were filled with composite (Filtek Z-250), thermal cycled (500 cycles), immersed in basic fuchsine solution, and longitudinally sectioned. Dye penetration was evaluated using optical-microscopy and scored. Data were analyzed by Kruskal-Wallis test (P = 0.05). Results: Overall, leakage in dentin was similar to that in enamel. In enamel margins, only the group with Cavit® cement associated with AP presented significant higher leakage. In dentin margins, AP exhibited higher leakage than the groups restored with SB; there was no significant difference between eugenol-free cement and ZOE-TC. Conclusion: In general, SB showed better marginal sealing than AP, and ZOE-TC did not increase dye leakage. Eugenol in the temporary cement did not affect the marginal sealing of adhesive restorations.

Objetivo: Este estudo in vitro avaliou a influência de um cimento restaurador temporário à base de óxido de zinco-eugenol (CT-OZE) no selamento marginal de restaurações diretas, utilizando dois sistemas adesivos. Metodologia: Cavidades classe V foram preparadas em 20 incisivos bovinos e restauradas com dois cimentos temporários, CT-OZE (IRM®) ou cimento livre de eugenol (Cavit®) (n=10/cimento temporário). Após sete dias, cinco dentes de cada grupo de cimento temporário foram restaurados utilizando o sistema Single Bond® (SB) e os demais cinco com o sistema Adper Prompt® (AP). As cavidades foram restauradas com resina composta (Filtek Z-250), termocicladas (500 ciclos), imersas em fucsina básica e longitudinalmente seccionadas. A penetração do corante foi avaliada em microscópio ótico. Os dados foram analisados por teste de Kruskal-Wallis (P = 0,05). Resultados: A infiltração em dentina foi similar à do esmalte. Em esmalte, o grupo com Cavit® e AP apresentou infiltração significativamente maior. Em dentina, AP exibiu maior infiltração que SB, e não houve diferença entre CT-OZE e Cavit®. Conclusão: Em geral, SB produziu melhor selamento marginal que AP, e CT-OZE não aumentou a penetração de corante. A presença de eugenol no material restaurador temporário não afetou o selamento marginal de restaurações adesivas.

Radiographic view of adhesive layer andrelationship with marginal leakage in class II composite resin restorations

This study assessed the influence of the application of bonding agents prior to or after matrix and wedge placement in the radiographic view of the adhesive layer in cervical walls of Class II composite resin restorations and correlated the findings with marginal leakage. Standard cavities were prepared in the mesial and distal faces of human molars, with cervical margins placed in dentin/cementum. Restorations were made using metallic matrix bands and wooden wedges. The microhybrid composite Filtek Z250 (3M ESPE) and two adhesive systems – Single Bond 2 (SB-3M ESPE) and Scotchbond Multi-Purpose (SMP-3M ESPE) – were used, thus defining five groups (n= 12): [SB1] and [SMP1]- matrix and wedge placed after bonding application; [SB2] and [SMP2]-matrix and wedge placed prior to bonding application; [Control] – restorations without adhesive system. Bitewing radiographs from each tooth were obtained and the view or not of the adhesive layer in the cervical wall of each restoration was observed under magnification (40x). Specimens were thermalcycled and dye penetration (0.5% basic fuchsine) evaluated under magnification (40x). Data were submitted to Kruskal-Wallis and Spearman correlation tests (p=0.05). The placement of matrix and wedge before bonding agent application increased the view of the adhesive layer only for SB (p<0.001). Matrix did not influence marginal leakage, and no significant relationship between radiographic view of adhesive layerand marginal leakage (r=-0.020; p =0.877) could be observed. In conclusion, SB presented better sealingability than SMP (p<0.01).