Oral Biofilms Flashcards
at what stage in the life cycle of a parasite are biofilms present?
- attachment of parasite (using fimbrae, pilli, capsule)
- consolidation and multiplication in host (forming micro colonies)
what is a biofilm?
matrix-enclosed bacterial (or fungal) populations adherent to each other and or to surfaces or interfaces
benefits of being a biofilm?
- protective environment
- coordinated cellular events
- division of labour (certain cells do certain things)
- ExtraPolymericSubstrate traps nutrients & prevents antibiotics getting to cell
- less energy used
- survival in numbers
do microorganisms prefer to be on their own or in a biofilm?
biofilm
where are biofilms important?
- teeth (plaque)
- drinking water (lead to diseases)
- medical implants
- food processing
what does planktonic mean?
free floating cell
what is the disadvantage of being planktonic bacteria?
susceptible to antibiotic as there is only one (no barriers)
what does micro-colony mean?
more than one bacteria coming together for protection
what does extra polymeric material do in a micro colony?
protects and surrounds bacteria
what would happen to a mature biofilm in a sustained microbial attack?
would be most protected and be able to rebuild itself
in terms of dentistry what is the planktonic cell?
organism in saliva
where do micro-colonies form in the oral environment?
find the enamel and then form on it
what does a micro-colony turn into if you don’t brush your teeth regularly?
mature biofilm
what are the 5 steps to biofilm development?
adhesion
colonisation
accumulation
complex community
dispersal
what are biofilms resilient to?
antimicrobials
how would you get rid of a biofilm in the mouth?
have to physically detach it
what are the 3 essential elements to ensure a biofilm can develop?
micro-organism
conditioning film (sticky in mouth due to carbs, proteins etc )
surface (enamel, gum, other bacteria)
what is the conditioning factor in the mouth?
saliva
what is glycocalyx composed of?
exopolymeric substrate
what is an essential component to make something a biofilm?
glycocalyx
what does glycocalyx do?
- maintains hydrated environment
- helps maintain tissue-like integrity
- provides protective barrier (immune factors and antibiotics)
what are micro colonies like in glycocalyx?
organised allowing active diffusion
what does extra polymeric material do for oral biofilms?
protects them
who first found plaque?
Antony van leewenhook
what is dental plaque?
a diverse microbial community (predominantly bacteria) found on the tooth surface, embedded in a matrix of polymers of bacterial and salivary origin
what is the main etiological agent associated with caries and periodontal disease?
dental plaque
what mucosal infection do oral biofilms cause?
thrush
angular cheilitis
denture stomatitis
what periodontal infections can oral biofilm diseases cause?
gingivitis
periodontitis
what is the endodontic infection that oral biofilm diseases can cause?
root canal
what types of caries can oral biofilm diseases cause?
coronal caries
root surface caries
what oral malodour can oral biofilm diseases cause?
dorsal surface of tongue
how many types of bacteria species can be found in the mouth?
at least 700 types
where are bacteria found in the mouth?
predominantly on hard tissues
- dorsum of tongue
- soft tissues (shedding)
are there any microbes in the mouth at birth?
how do the microbes come?
no sterile at birth
- food, milk, water, mothers saliva
what species are critical in forming a biofilm in the oral cavity?
Streptococcus
eg. S. salivarus or S. mitis
what can change the oral microbiology?
age:
irruption of teeth
puberty (gram negative and spirochaetes)
what is the main determent for colonisation in the oral environment?
saliva:
10^8 cfg/ml
salivary proteins
at what stage in your life are you more impacted by cryogenic organisms?
young
what are the 4 steps to plaque development?
- colonisation by pioneer bacteria
- outgrowth of microbacteria
- secondary colonisation
- climax community
what are the 6 stages in caries forming?
adhesion
survival and growth
biofilm formation
complex plaque
acid
caries
does the biofilm in the mouth like acid or alkali?
acid
at what point in plaque development do the outcomes of oral disease happen?
climax community
what happens at the climax community stage of plaque development?
polysaccharide production
synergistic metabolic interactions
what would a high protein diet lead to?
- few acidogenic organisms -> ammonia produced
- more gram-negative
- secondary metabolites therefor malodour
what are high protein diets associated with?
malodour and tissue destruction
what is a high carb diet associated with?
supports production of organisms such as streptococcus
what would a high carbohydrate diet lead to?
- metabolism reduces pH
- aciduric organisms thrive
- streptococci and lactobacilli
what would a sudden change in the oral environment lead to? (ecological plaque hypothesis)
the nasty pathogens can get into the healthy biofilm and cause diseases
are biofilms difficult or easy to treat?
they are difficult to treat
