Title: INITIAL BACTERIAL COLONISATION IN CHILDREN WITH DIFFERENT LEVELS OF CARIES ACTIVIY – AN IN-SITU-STUDY
Co-Author(s): Alexandra Wolf, Susann Grychtol, Sabine Basche, Stefan Rupf, Matthias Hannig, Christian Hannig
INTRODUCTION: Caries in childhood is one of the most abundant chronic infectious disease worldwide and causes destruction of the teeth. Initial bioadhesion processes are the reason for caries disease and have been variously studied in adults. The aim of this clinical and experimental in situ study was the visualization and quantification of initial microbial colonisation of enamel surfaces in children with different levels of caries activity.
METHODS: A number of 29 children (age 5-9) participated in the study and were divided into three groups of different caries activity according to dmf/t index. Initial biofilm formation was performed on bovine enamel slabs mounted buccally on individual splints in the upper jaw and carried for 8 h overnight, respectively. After intraoral exposure, the adherent bacteria and glucans were visualised and quantified with flourescence microscopic methods. This was subjected to a combined DAPI-/Concanavalin A -staining to determine adherent bacteria and glucans. Fluorescence in situ hybridization (FISH) was used for distinction of eubacteria, streptococci and Candida albicans, respectively. Furthermore, salivary samples were investigated for Candida using Calcofluor White-staining (CFW) and for S. mutans using CRT® bacteria test.
RESULTS: With all flourescence methods, bacteria were detected on the enamel slabs, but not Candida albicans. The microorganims were distributed randomly in small aggregates and the numbers of bacteria revealed high intraindividual and interindividual variability. Caries activity showed no statistically significant impact on the distribution pattern of the adherent bacteria during initial bacterial colonisation. Investigaion of salivary samples by CFW-staining indicated fungal structures and Candida cells in caries-free, caries-active and rehabilitated children. Data from CRT® bacteria test revealed the significantly lowest amount of S. mutans colonies in caries-free children.
CONCLUSION: The pattern of initial bacterial colonisation of the enamel surface in children is not influenced by caries activity.