Since
dentures can serve as a reservoir for
halitosis-causing oral bacteria,
halitosis development is a concern for denture wearers. In this study, we surveyed the prevalence of four selected
halitosis-related species (Fusobacterium nucleatum, Tannerella forsythia, Veillonella atypica and Klebsiella pneumoniae) in clinical denture plaque samples, and developed denture biofilm models for these species in vitro to facilitate assessment of antimicrobial treatment efficacy.
Design : Denture plaque from ten healthy and ten
denture stomatitis patients was screened for the presence of aforementioned four species by PCR. Biofilm formation by these
halitosis-associated species on the surfaces of
denture base resin (DBR) discs was evaluated by
crystal violet staining and confocal
laser scanning microscopy. The efficacy of
denture cleanser treatment on these mono-species biofilms was evaluated by colony counting. Results : 80% of the subjects in the
denture stomatitis group and 60% in the healthy group contained at least one of the targeted
halitosis-related species in their denture plaque. All
halitosis species tested were able to form biofilms on DBR disc surfaces to varying degrees. These in vitro mono-species resin biofilm models were used to evaluate the efficacy of
denture cleansers, which exhibited differential efficacies. When forming biofilms on resin surfaces, the
halitosis-related species displayed enhanced resistance to
denture cleansers compared with their planktonic counterparts. Conclusion : The four selected
halitosis-related bacterial species examined in this study are present on the majority of
dentures. The mono-species biofilm models established on DBR discs for these species are an efficient screening tool for dental product evaluation.