Why Are Those Teeth Loose?

If you remember your occlusion course from dental school, you probably remember being taught that contacts should be cusp tip to marginal ridge or cusp tip to transverse or oblique ridge. So what happens when that isn't possible? If you look at the image, you should notice two things – the premolar on the left side of the screen and the centric stops on the front teeth.

This patient had four premolars removed for orthodontic purposes over 25 years ago. He reports that at the time the ortho was completed he didn't have any spaces between his front teeth. During his exam it was noted that there was grade 1 mobility on all six maxillary anteriors and with both maxillary premolars. All of those teeth probed less than 2mm with no bleeding or radiographic evidence of bone loss, but they all have widened PDL spaces.

This patient also has massive masseter muscles and reports that he catches himself clenching when he first awakens and sometimes during the day while he is working. He's a dentist—of course! He has no symptoms in either joint and his range of motion is normal.

What do you think is going on here? What are the possible causes of the mobility? Why are the teeth moving? There are lots of clues here and I'll follow up with my thoughts in a future article.