In this study of "probiotic" treatment, researchers used bacteria replacement therapy on male beagle dogs after scaling and root planning.The study divided the dogs into four groups: A negative control group that received no treatment, a positive control group that received subgingival scaling and root planning, a group that received a single application of bacterial mixture, and one that received multiple applications. The multiple applications group had the greatest reduction in anaerobic and black-pigmented bacteria, followed by the single application group. The multiple application group also showed maximum reduction in levels of P. gulae.

Wim Teughels, corresponding author and professor in the Department of Periodontology at Catholic University Leuven, noted in a press release that additional studies must be conducted to assess the viability of this treatment in humans. Marc Quirynen, principal investigator and a professor at Catholic University Leuven, and his team are continuing to test non-pathogenic bacteria that are helpful to humans, noting "We hope the current study will inspire other investigators to consider periodontal disease therapy from this novel perspective."