Biology EE - Evaluation of topic

[Artoth]

My topic is "Influence of oral hygiene agents (still not sure if I can name them like this) on pH of saliva"

This topic is way to simple to be chemistry, as I am simply measuring the changes in pH of saliva after certain time periods. I'm not sure if this topic is suitible enough for EE, for Biology I connect it with dental plaque, how acidic enviroment is good for bacteria to produce dental plaque.

What do you think about this topic?

[ShineeLikeMe]

I feel like this would be a very interesting topic. Espcially if you were to go in depth about the anatomy of the mouth and enzyme and and the agent affects it. For it to be an EE though I think you need to actually carry out an experiement. I feel like it would be best as a Biology paper including some biochemistry.

[Artoth]

To be more specific, I already did the investigation part, there are some interesting conclusions, like in case of change of pH even the chewing gum containing sugar is better than brushing teeth, but still it just is about changes in pH ; ) I will concentrate probably more on salivary glands as they are being stimulated by hygiene agents and this causes biggest changes in pH. So this topic is biological enough? I was reading here about these experiments involving only plaants and bacteeeria and I got a bit scared. In my school my year is the first one in the history of school to be in IB programe so it is still new for our teachers. Because of this I'm bit scared about my CAS, ToK, EE and internal from nearly allll subjects

[Sandwich]

The problem with doing just salivary pH and then assuming that that means more bacterial death is that actually the physiology of salivary output (and pH) is to do with a lot of different variables. The pH is actually affected by the rate of salivary flow (it's a system of ion exchange, look it up!), for instance. So if you found that chewing gum was very good at changing the pH of saliva, it's at least partly because the gum causes an increased rate of secretion... however if it's got sugar in the gum, it doesn't necessarily imply a positive effect re: dental plaque levels, even though the saliva's pH seems to change a lot!

Basically, there are a lot of variables (and processes) it's difficult to control for. Just because pH changes, it doesn't necessarily imply that the amount of dental plaque reduces. To analyse along those lines would be to analyse on the basis of an assumption that pH change always == dental plaque change. If you were going to go down that route, you'd really have to measure actual dental plaque itself. OR find some sound evidence that pH is the major controller of dental plaque (I'm not 100% on whether it is or isn't, I don't actually know much about dental plaque!) OR control for all your other variables.