Fig. 4: Pulsed electromagnetic field (PEMF) evaluated in terms of in vitro polymicrobial biofilm formation.

Microbiological composition of in vitro biofilms was evaluated by checkerboard DNA–DNA hybridization technique, to assess the presence and levels of 40 bacterial species associated to dental implant-related infections. A Levels (x10⁵) of 40 bacterial species evaluated for both groups, pulse (activated PEMF) and control (non-activated) as average and standard deviation. B Periodontal microbial complexes by bacterial proportion. Bacterial species were grouped as previously described for microbial complexes related to oral infections. C Fold change of bacterial counts from control group divided by the counts in pulse group. Three bacterial species more associated with tissue damage in dental implant-related infections. During biofilm maturation and disease progression, initial colonizers start the process (complexes: Actinomyces – blue, yellow, green, and purple), followed by secondary colonizers (orange complex) that promote biofilm growth and create a suitable environment for the colonization of late colonizers (red complex), which are highly associated with tissue damage. * Indicates statistical difference (p < 0.05) by t-test.