A comparative study of bulk-fill composites: degree of conversion, post-gel shrinkage and cytotoxicity

Autor(es)

Flávia Gonçalves ^[1] ; Luiza Mello de Paiva Campos ^[2] ; Ezequias Costa Rodrigues-Júnior ^[3] ; Fabrícia Viana Costa ^[4] ; Pamela Adeline Marques ^[5] ; Carlos Eduardo Francci ^[6] ; Roberto Ruggiero Braga ^[6] ; Letícia Cristina Cidreira Boaro ^[8]

Afiliação do(s) autor(es)

^[1] Universidade Ibirapuera - Brasil

^[2] Univ Sao Paulo, Inst Energy & Nucl Res, Lab Polymers & Nanotechnol, Sao Paulo, SP - Brazil

^[3] Universidade de São Paulo – USP. School of Dentistry. Department of Biomaterials and Oral Biology - Brasil

^[4] Universidade de Santo Amaro – Unisa. School of Dentistry - Brasil

^[5] Univ Santo Amaro Unisa, Sch Dent, Sao Paulo, SP - Brazil

^[6] Univ Sao Paulo, Sch Dent, Dept Biomat & Oral Biol, Sao Paulo, SP - Brazil

^[7] Universidade de Santo Amaro – Unisa. School of Dentistry - Brasil

• Tipo de documento: Artigo Científico
• Fonte: Brazilian Oral Research; v. 32, 2018-03-08.

Resumo

Abstract: Bulk-fill composites are claimed to be restorative materials used in deep preparations and effectively photoactivated in layers up to 4 mm. The aim of the present study was to evaluate the degree of conversion, post-gel volumetric shrinkage, and cytotoxicity of six bulk-fill and two conventional composites. Degree of conversion was determined by FTIR spectroscopy; post-gel volumetric shrinkage was determined using the strain gauge method; and cytotoxicity in human fibroblasts was evaluated indirectly by the MTT assay. Data were subjected to one-way ANOVA/Tukey's test (α = 0.05). All materials, including bulk-fill and conventional composites, were classified as non-toxic, with cell viability higher than 70%. Bulk-fill composites exhibited volumetric shrinkage similar to or lower (1.4 to 0.4%) than that of conventional composites (1.7–2.1%). However, only four of the bulk-fill composites were able to sustain a homogeneous conversion at the 4-mm depth. Despite their non-toxicity and shrinkage similar to that of conventional materials, not all commercial bulk-fill materials were able to maintain a conversion as high as 80% of the superficial layer, at the 4-mm depth, indicating some failure in the bulk-fill design of some commercial brands. Therefore, the use of bulk-fill materials in dental practice is advantageous, but special attention should be given to the selection and correct use of the materials. (AU)

• Processo FAPESP: 13/07229-3 - Estudo da adição de nanopartículas argilominerais em matrizes poliméricas fotoativadas a base de bisgma/tegdma, aplicadas à odontologia.
• Beneficiário: Luiza Mello de Paiva Campos
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 16/01319-9 - Desenvolvimento de nanocompósitos odontológicos a base de BisGma/TEGDMA com atividade antimicrobiana utilizando nanopartículas de MMT carregadas com clorexidina
• Beneficiário: Letícia Cristina Cidreira Boaro
• Modalidade de apoio: Auxílio à Pesquisa - Regular