Influence of different enamel substrates on microtensile bond strength of sealants after cariogenic challenge
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Published on: December 20, 2024
Kamila Rosamilia Kantovitz1, Fernanda Miori Pascon, Marcelo Correa Alves
1Department of Pediatric Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, SP, Brazil.
Purpose:
To evaluate the microtensile bond strength (μTBS) of resin sealer on enamel substrates after cariogenic challenge.
Materials And Methods:
Enamel blocks were obtained from human third molars and randomly divided into 6 groups (n = 10) according to enamel substrates (S: sound, CL: caries-like lesion, or CLTF: caries-like lesion + topical fluoride application) and sealant material (F: FluroShield, or H: Helioseal Clear Chroma). Sealants were placed on enamel surfaces, stored in 100% humidity (24 h, 37°C), and longitudinally sectioned into hourglass shapes. According to the groups, pH cycling was applied and the μTBS test was performed. The fracture patterns were assessed by SEM.
Results:
Regarding substrates, the highest μTBS values in MPa were observed for CLTF enamel (26.0 ± 7.6), followed by S (22.0 ± 7.4) and CL (15.5 ± 4.9). A significant interaction was found between material and pH cycling (p = 0.0395). F (23.9 ± 7.6) showed higher μTBS values than H (18.3 ± 7.5) when submitted to pH cycling. The majority of samples presented mixed failure.
Conclusions:
Enamel substrate significantly affected μTBS, with the highest values for remineralized caries-like enamel lesions. Furthermore, μTBS values were dependent on both materials and pH cycling.
