The Skeleton King posted:

Calculus (the hard, barnacle-like plaque) tends to form differently for everyone. It's hard to predict, simple to prevent. Flossing frequently is the most effective way to prevent it (though you should see a hygienist every year at the very least to make sure that nothing has set up shop).

Flossing is important, and just because nothing noticeable has appeared yet does not mean it won't, or that it isn't already in progress. Periodontal disease is a mysterious beast that can appear suddenly or just sit around and do nothing for long periods of time.

The best early sign of disease is if your gums bleed easily when brushing or flossing. This is called gingivitis, and is a clear indicator of the presence of bacteria colonization beneath the gums. Consistent brushing and flossing routines can fix this over time, but if it persists, contact a dental clinic and get a cleaning.

If you can't get things between your teeth, I'd recommend looking into a water pick.