A biofilm is a highly organized structure consisting of bacterial cells enclosed in a self-produced extracellular polymeric matrix attached on a surface. Root canal infections are biofilm mediated. The complexity and variability of the root canal system, together with the multi-species nature of biofilms, make disinfection of this system extremely challenging.

1. Dr. K. PALANI SELVI MDS

2. • Introduction
• Definition
• Basic criteria
• Characteristics
• Ultrastructure of a biofilm
• Formation and factors affecting its formation
• Endodontic biofilms
• Role of E.feacalis
• Microbial diversity in endodontic biofilm
• Current therapeutic options in endodontic
biofilm
• Eradication of biofilm
• Biofilm assessment methods
• Conclusion

3. • From an ecological perspective,
the root canal can be considered a
highly controlled environment
with a limited number of niches.
• The main limiting factors in root
canal niches that influence
bacterial colonization are, for
instance, oxygen and nutrient
availability .
INTRODUCTION
JOE - Redefining the Persistent Infection
in Root Canals: Possible Role of Biofilm
Communities - Luis Chávez 2014

4.  Biofilm is defined as a sessile multi cellular microbial
community characterized by cells that are firmly attached
to a surface and embedded in a self produced matrix of
extracellular polymeric substances
 Biofilms are formed whenever there is free flow of fluid ,
microorganisms and a solid surface. It is one of the basic
survival strategies employed by bacteria
DEFINITION
•
Costerton JW, Lewandowski Z, DeBeer D, Caldwell D, Korber D, James G. Biofilms, the customized microniche.
J Bacteriol. 1994;176:2137-42.

5. Caldwell DE, Atuku E, Wilkie DC, Wivcharuk KP, Karthikeyan S, Korber DR, et al. Germ theory
vs. community theory in understanding and controlling the proliferation of biofilms. Adv Dent Res.
1997;11:4-13.
Biofilms should possess
1. AUTOPOIESIS- ability to self organize
2. HOMEOSTASIS-resist
environmental pertubations
3.SYNERGY- effective in association
than in isolation
4.COMMUNITY- respond to environmental
changes as a unit rather than single individual

6. ULTRASTRUCTURE OF A BIOFILM

7.  Basic structure - heterogenous arrangement of microbial
cells on a solid surface
 Glycocalyx matrix - Extrapolymeric substance surrounds
the microcolonies and anchors the bacterial cell to the
substrate
 85% - matrix and 15% - cells
 Mushroom shape/ tower shape
 Water channels are primitive circulatory system in
biofilms
ULTRASTRUCTURE OF A BIOFILM
85% MATRIX
15% CELLS

8.  First stage - a conditioning film forms-
transport of microbe to the substrate surface
 Second stage – initial non-specific
microbial-substrate adherence phase
 Third stage - Bacterial growth and biofilm
expansion
 Fourth stage - Detachment of biofilm

9. STAGES OF BIOFILM FORMATION

10.  PH, temperature, surface energy of substrate, flow rate
of fluid, nutrient availability, bacterial growth stage,
surface hydrophobicity

14. • Erosion- continousdetachment of single cells and small
portions of biofilm
• Sloughing- rapid massive loss of biofilm

18.  Forms on root canal
dentin of an infected tooth
 Identified by Nair 1987
 Cocci, rods , filaments and
spirochetes are seen
 Morphologically distinct type
of bacteria are seen
 Eg- E.faecalis

19.  Root surface biofilms - adjacent to root
apex of endodontically treated teeth
 Seen in teeth with asymptomatic
periapical periodontitis and chronic
apical abscess with sinus tract
 Multispecies in nature- F. nucleatum,
Po. gingivalis, and Tannerella forsythensis
 Dominated by cocci and short rods
with cocci attached to tooth substrate

20.  Isolated biofilms in the
periapical area of endodontically
involved teeth
• Eg- Actinomyces , P.propionicum

21.  Bacteria adheres to artificial biomaterial
surface and forms biofilms
 Opportunistic infection- nosocomial
organisms
 Eg- coagulase negative staphylococcus, s.
aureus, enterococci, streptococci,
p.aeruginosa
 Serum plays a significant role in biofilm
formation
 GP coated with biofilm

22. E. FEACALIS & BIOFILM
• E. faecalis is a gram-positive,
facultative anaerobic cocci that
is strongly associated with
endodontic infections.
• It causes nosocomial infections
• Frequently isolated from the
failed root canals undergoing
retreatment.
Duggan JM, Sedgley CM. Biofilm formation of oral and endodontic Enterococcus faecalis. J Endod.
2007;33:815-8. Al-Ahmad A, Muller N, Wiedmann-Al-Ahmad M, Sava I, Hubner J, Follo M, et al.
Endodontic and salivary isolates of Enterococcus faecalis integrate into biofilm from human salivary
bacteria cultivated in vitro. J Endod. 2009;35:986-91.
• They can grow in
- extremely Alkaline pH,
- salt concentrated environment
- survive a temperature of 60°C for 30 min.
• E. faecalis is able to suppress the action of
lymphocytes, potentially contributing to
endodontic failure.
• E.faecalis has the ability to form biofilm that
can resist calcium hydroxide dressing by
maintaining pH homeostasis.

23. The development of E. faecalis biofilm on the
root canal dentin involves three stages as follows:
Stage 1:
Microcolonies are formed
as E. faecalis cells adhere
on the root canal dentin
surface
Stage 2:
Bacterial-mediated dissolution of
the mineral fraction from the dentin
substrate leads to localized increase
in the calcium and phosphate ions
causing mineralization (or
calcification) of the E. faecalis
biofilm
Stage 3:
Due to this interaction of
bacteria and their metabolic
products on dentin, E. faecalis
biofilm is mineralized.

25. CURRENT THREUPATIC OPTIONS FOR ENDODONTIC BIOFILM

26. OZONE
ULTRASONIC
IRRIGATION

29. • Micromanipulator-assisted analysis
• Green fluorescent protein (GFP) tagging
• Confocal laser scanning microscopy (CLSM)
• Flow cytometry
• Fluorescence in situ hybridization (FISH)
- have made biofilm characterization very comprehensive.

30. • It is foremost to understand that how the
biofilm formed by root canal bacteria
resists endodontic treatment measures.
• Elimination or significant reduction of
endodontic bacterial biofilms and
prevention of recontamination of the root
canal after treatment are the essential
elements for successful outcomes of
endodontic treatment.
CONCLUSION