Bacterial colonization of enamel in situ investigated using fluorescence in situ hybridization.
Oral biofilms are one of the greatest challenges in dental research. The present study aimed to investigate initial bacterial colonization of enamel surfaces in situ using fluorescence in situ hybridization (FISH) over a 12 h period. For this purpose, bovine enamel slabs were fixed on buccal sites of individual splints worn by six subjects for 2, 6 and 12 h to allow biofilm formation. Specimens were processed for FISH and evaluated with confocal laser-scanning microscopy, using probes for eubacteria, Streptococcus species, Veillonella species, Fusobacterium nucleatum and Actinomyces naeslundii. The number of adherent bacteria increased with time and all tested bacterial species were detected in the biofilm formed in situ. The general percentage composition of the eubacteria did not change over the investigated period, but the number of streptococci, the most frequently detected species, increased significantly with time (2 h: 17.7+/-13.8 %; 6 h: 20.0+/-16.6 %; 12 h: 24.7+/-16.1 %). However, < or =1 % of the surface was covered with bacteria after 12 h of biofilm formation in situ. In conclusion, FISH is an appropriate method for quantifying initial biofilm formation in situ, and the proportion of streptococci increases during the first 12 h of bacterial adherence.
Al-Ahmad
Ali
A
Department of Operative Dentistry and Periodontology, University of Freiburg, Hugstetter Strasse 55, D-79106 Freiburg, Germany.
Follo
Marie
M
Department of Hematology and Oncology, Core Facility, Albert-Ludwig University, D-79085 Freiburg, Germany.
Selzer
Ann-Carina
AC
Department of Operative Dentistry and Periodontology, University of Freiburg, Hugstetter Strasse 55, D-79106 Freiburg, Germany.
Hellwig
Elmar
E
Department of Operative Dentistry and Periodontology, University of Freiburg, Hugstetter Strasse 55, D-79106 Freiburg, Germany.
Hannig
Matthias
M
Clinic of Operative Dentistry, Periodontology and Preventive Dentistry, University Hospital, Saarland University, Building 73, D-66421 Homburg/Saar, Germany.
Hannig
Christian
C
Department of Operative Dentistry and Periodontology, University of Freiburg, Hugstetter Strasse 55, D-79106 Freiburg, Germany.
D000190:Actinomyces / Q000235:genetics / Q000302:isolation & purification; D000818:Animals; D001419:Bacteria / Q000235:genetics / Q000302:isolation & purification / Q000648:ultrastructure; D001422:Bacterial Adhesion / Q000235:genetics; D001483:Base Sequence; D018441:Biofilms / Q000254:growth & development; D002417:Cattle; D004269:DNA, Bacterial / Q000235:genetics; D003743:Dental Enamel / Q000382:microbiology* / Q000648:ultrastructure; D016967:Fusobacterium nucleatum / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D013291:Streptococcus / Q000235:genetics / Q000302:isolation & purification; D014678:Veillonella / Q000235:genetics / Q000302:isolation & purification
D004269:DNA, Bacterial