1mm or more. Deep tooth wear is a kind of tooth dressing technology, which can be used to raise occlusion. This technique can increase occlusal depth, thus improving oral occlusal function, improving masticatory function, avoiding the influence of sciatica and other pains, and improving patients' occlusal ability. Traditional dressing technology can increase the occlusal height by 0.5- 1 mm, while deep grinding technology can increase the occlusal height by more than 1 mm.