The “Physical methods” category refers to reviews (5.7%) and trials (2.9%) that aim to biofilm removal using physical or mechanical approaches, such as heating or brushing. As discussed above, these strategies are generally not sufficient to eradicate biofilms, and are often combined with antimicrobial administration. Cell dispersion originating from mechanical actions may generate new infection foci and lead to development of resistance [i,ii]. Moreover, dead and lysed cells can stimulate biofilm growth, due to the ability of biofilms to recycle cellular components [iii]. On the other hand, using biocides as antibiofilm strategies is sometimes inappropriate or unsuc-cessful due to increasing resilience of biofilms [iiii].
Physical strategies presented in basic research reviews are more sophisticated than in clinical trials, at least in our analysis of these data. Specifically, while trials in this cat-egory explore conventional brushing or mechanical removal, reviews include ap-proaches such as photodynamic therapy or acoustic cavitation [v,vi].
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