Concentrated MTA Repair HP reduced biofilm and can cause reparative action at a distance.

ABSTRACT

AIM: To evaluate in vitro whether MTA Repair HP can induce repair processes at a distance, including its effects on biofilm, cell viability, migration, production of TGF-ß, phosphate and ALP, evaluated through MTA diluted extracts. METHODOLOGY: Initially, antibacterial tests were performed with the bacterium Streptococcus mutans (ATCC 25175) in the presence of MTA extracts (dilutions of 11, 12 and 14). Growth inhibition assay by microdilution in broth, antibiofilm plate assay of young biofilm and antibiofilm assay in confocal microscopy of mature biofilm were carried out. Then, pulp cells were stimulated in the presence of several MTA dilutions, and cell viability (MTT assay), proliferation and migration capacity (scratch assay) were evaluated. To evaluate the capacity of 11, 12 and 14 dilutions of MTA Repair HP to promote the production of important agents of odontogenic differentiation and mineralization, ALP activity, TGF-ß secretion and phosphate quantification were measured. Statistical differences were verified using one-way and two-way anova and Tukey's post-tests. RESULTS: The test dilutions of MTA Repair HP did not inhibit planktonic S. mutans growth but were able to reduce young and mature S. mutans biofilm (p < 0.001). In addition, none of the MTA Repair HP dilutions was cytotoxic for pulp cells. The 12 and 14 dilutions of MTA Repair HP induced migration and proliferation of pulp cells (p < 0.05). ALP activity and TGF-ß secretion were independent of the tested dilution (p < 0.001). Diluted 14 MTA Repair HP produced less phosphate than the more concentrated 11 and 12 MTA dilutions (p < 0.001). CONCLUSIONS: Undiluted MTA Repair HP reduced S. mutans biofilm, when compared to 12 and 14 MTA dilutions. Furthermore, none of the tested dilutions was cytotoxic to pulp cells. MTA Repair HP promoted cell migration and proliferation at a distance, assessed through the dilution of the MTA. Even from a distance, MTA Repair HP has the ability to participate in some events related to repair, such as migration, proliferation and TGF production.