A novel in vitro model system to grow films of oral bacteria for the study of human tooth root surface caries.
OBJECTIVE
To develop a simple and flexible novel in vitro model system to grow films of oral bacteria that could be used to study aspects of dental caries.


RESULTS
Standardized suspensions of bacteria were inoculated into Ultrafree-CL (Millipore) ultrafiltration units at various densities. These were incubated for varying time intervals with a range of carbon sources. The bacterial films reproducibly achieved between 107 and 108 cfu cm-2, irrespective of the number inoculated and with no significant changes for 14 d. However, Streptococcus mutans grew through membranes with pores of diameter greater than 0.1 microm after 6 d. Culture of films in sucrose or water for 6 d led to a decreased number of colony-forming units, but returning them to broth reversed this.


CONCLUSIONS
Reproducible films of oral bacteria can be cultured in Ultrafree-CL units.


CONCLUSIONS
This study has shown that Ultrafree-CL units can be used as a simple model system to grow biofilms that could be used for dental caries research.
Aldsworth
T G
TG
Department of Oral Sciences, Glasgow Dental Hospital and School, Glasgow, Scotland, UK. timothy.aldsworth@nottingham.ac.uk
MacFarlane
T W
TW
D018441:Biofilms / Q000254:growth & development*; D015169:Colony Count, Microbial; D003470:Culture Media; D006801:Humans; D008851:Micropore Filters / Q000382:microbiology*; D008954:Models, Biological; D009055:Mouth / Q000382:microbiology; D017213:Root Caries / Q000382:microbiology*; D013295:Streptococcus mutans / Q000254:growth & development*
D003470:Culture Media