[The role of dead bacteria in streptococcus sanguis biofilm reformation].
OBJECTIVE
To investigate the role of dead bacteria in Streptococcus sanguis biofilm reformation.


METHODS
Vital fluorescent staining technique and Confocal laser Scanning Microscopy (CLSM) were combined to observe Streptococcus sanguis biofilm on the saliva-coated glass (SCG) in an artificial mouth model, the thickness and bacterial density were compared between biofilm reformed on saliva covered slide with dead cells (test group) and biofilm reformed on saliva coated slide without dead cells (control group) at different times.


RESULTS
At 30 min, the bacterial density rather than biofilm thickness of test group was significantly higher than that of control group (P<0.05), whereas at 60 min, 120min, 240min, the biofilms were significantly thicker in test group than that (P<0.05).


CONCLUSIONS
The dead cells may help biofilm reformation during the formation of biofilm.
Department of Stomatology, Ninth People's Hospital, Shanghai Second Medical University, Shanghai 200011, China. marui66@hotmail.com
Rui
R
Ma
Min
M
Zhu
Zheng
Z
Liu