Sir, I sympathise with both Dr Holland and Dr Aggarwal (BDJ 2008; 205: 104). One may have found more evidence than the other but most of it is negative and none of it tells us why occlusal problems exist. To use a homely simile, the evidence shows that the faster you drive over a crossroad the less likely you are to have a collision. These are both situations where the evidence can lead you in the wrong direction. Logic is needed to create sense out of disjointed evidence.

In the natural environment aeons ago, the teeth wore into a perfect mesh but soft diet and open mouth postures destroy this relationship. You can dream up a thousand research projects to examine modern occlusal disharmony but few if any of them will lead to an effective cure. Be logical and you will realise that if the teeth are in contact enough (four to eight hours each day?) the cure is automatic.1

Okay, patients can't (won't) do that! Yes they can; a Stage 3 Biobloc appliance2 correctly adjusted and worn will teach them to keep their teeth in contact all night every night and within a month all the teeth will occlude equally. Incidentally it also cures malocclusion, TMD and OSA. We all need to be a bit more logical.