Impact of calcium aluminate cement with additives on dental pulp-derived cells

Abstract Calcium aluminate cement (CAC) has been highlighted as a promising alternative for endodontic use aiming at periapical tissue repair. However, its effects on dental pulp cells have been poorly explored. Objective: This study assessed the impact of calcium chloride (CaCl2) and bismuth oxide (Bi2O3) or zinc oxide (ZnO) additives on odontoblast cell response to CAC. Methodology: MDPC-23 cells were exposed for up to 14 d: 1) CAC with 2.8% CaCl2 and 25% ZnO (CACz); 2) CAC with 2.8% CaCl2 and 25% Bi2O3 (CACb); 3) CAC with 10% CaCl2 and 25% Bi2O3 (CACb+); or 4) mineral trioxide aggregate (MTA), placed on inserts. Non-exposed cultures served as control. Cell morphology, cell viability, gene expression of alkaline phosphatase (ALP), bone sialoprotein (BSP), and dentin matrix protein 1 (DMP-1), ALP activity, and extracellular matrix mineralization were evaluated. Data were compared using ANOVA (α=5%). Results: Lower cell density was detected only for MTA and CACb+ compared with Control, with areas showing reduced cell spreading. Cell viability was similar among groups at days one and three (p>0.05). CACb+ and MTA showed the lowest cell viability values at day seven (p>0.05). CACb and CACb+ promoted higher ALP and BSP expression compared with CACz (p<0.05); despite that, all cements supported ALP activity. Matrix mineralization were enhanced in CACb+ and MTA. Conclusion: In conclusion, CAC with Bi2O3, but not with ZnO, supported the expression of odontoblastic phenotype, but only the composition with 10% CaCl2 promoted mineralized matrix formation, rendering it suitable for dentin-pulp complex repair.

Effects of a novel calcium aluminate cement on the early events of the progressionof osteogenic cell cultures

The present study evaluated the progression of osteogenic cell cultures exposed to a novel calcium aluminate cement (CAC+) in comparison with the gold standard mineral trioxide aggregate (MTA). Cells were enzimatically isolated from newborn rat calvarial bone, plated on glass coverslips containing either CAC+ or a control MTA samples in the center, and grown under standard osteogenic conditions. Over the 10-day culture period, roundening of sample edges was clearly noticed only for MTA group. Although both cements supported osteogenic cell adhesion, spreading, and proliferation, CAC+-exposed cultures showed significantly higher values in terms of total cell number at days 3 and 7, and total protein content and alkaline phosphatase activity at day 10. The present in vitro results indicate that the exposure to CAC+ supports a higher differentiation of osteogenic cells compared with the ones exposed to MTA. Further experimental studies should consider CAC+ as a potential alternative to MTA when the repair of mineralized tissues is one of the desired outcomes in endodontic therapy.

O objetivo do presente estudo foi avaliar a progressão de cultura de células osteogênicas expostas a um novo cimento de aluminato de cálcio (CAC+) em comparação ao agregado de trióxido mineral (MTA). As células foram obtidas por digestão enzimática de calvária de ratos recém-nascidos, plaqueadas sobre lamínulas de vidro contendo em sua área central discos de CAC+ ou MTA e crescidas em condições osteogênicas por até 10 dias. Durante a cultura primária, observou-se o arredondamento das bordas das amostras de cimento apenas para MTA. Embora ambos os cimentos tenham permitido a adesão, o espraiamento e a proliferação celulares, as culturas crescidas em contato com CAC+ exibiram valores maiores de número total de células em 3 e 7 dias, e de conteúdo de proteína total e atividade de fosfatase alcalina em 10 dias. Os resultados indicam que a exposição ao CAC+ permite o desenvolvimento de uma proporção maior de células em estágios mais avançados da diferenciação osteoblástica, quando comparado ao MTA. Deve-se considerar em futuros estudos experimentais a utilização do CAC+ como um material alternativo ao MTA especialmente quando um dos objetivos do tratamento endodôntico é o de reparação dos tecidos mineralizados da região periapical.