There are some amazingly interesting ahadeeth which are on the back of my head regarding contemporary hygiene. Unfortunately I don't memorize them by heart. Nevertheless, I'm honored to share the gist of them with my dear friends.
1. Bad breath
A few years ago, I perused an informative article in The Star newspaper. It focused on handling the problem of bad breath. Interestingly, one of the dentistry ways to prevent bad breath is by brushing and cleansing our tongue.
SubhanAllah. This triggered me a hadith mentioning a time when our beloved prophet (saw) was brushing his teeth using miswak. And the narrator mentioned that whilst he was doing that, an "uukk .. uukk" sound-like came from his mouth. How else can a sound like that come from someone who is brushing his teeth, unless he was at the same time brushing his tongue!
To control bad breath IS part of the sunnah :)
Honestly, to me personally, one of the best opportunity to think deeply is when your with your ownself in the toilet. That's the time when everything is serene and peaceful and you're at ease (or easing yourself .. hehe).
When you are sitting at the bowl (before you leave a souvenir), try and look down. What you'll see is a still water. (Hint: the water in the bowl is not moving). One of the hadeeth that interest me is a hadeeth from our teacher (s.a.w) which prohibits easing ourselves in still water. In other words, it's either haram or makruh or undesirable for us to use the modern toilets!
Is that what it really means? But wait a moment. There IS a way, to make the water running! Ehe, therefore to flush the toilet after 'leaving the kids in the pool' is not only a direct sunnah but to NOT flush the toilet is in some sense makruh.
So please remember that, especially if you're living in Malaysia :)