Hi there,

I was just reading Dr Spear's excellent article on tooth wear and over-eruption in the latest issue

of Spear Digest and it got me thinking.....(I hope you can excuse the long narrative)

In cases of localised anterior tooth wear (with compensatory eruption) Orthodontic repositioning of the anterior teeth is a frequently cited treatment option.

In Europe, the Dahl Appliance (first described by Prof. Bjorn Dahl in 1975) receives a lot of support for this purpose.

Essentially, this involves the use of a localised appliance (such as adhesively bonded retainers - similar to Maryland bridge retainers) which are adhesively bonded onto the worn anterior teeth, placing them 'high in the bite'.

Space to restore the worn anteriors is then created by a combination of intrusion of the anteriors (in contact with the appliance) and eruption of the unopposed posterior teeth.

Dahl originally suggested that an occlusal bite platform be incorporated into the appliance to ensure that forces are directed down the long axis of the teeth, however more recently others have reported this is not essential. This means that simple direct composite or lab-made provisional restorations can be used as a 'Dahl appliance'.

One key to success is that the thickness of the material placed should directly relate to the amount of space required.

Studies suggest the average time for movement is 6-12 months and the risk of complications (pulpal - 4%, root resorption -0% , tmjd - 5%, periodontal discomfort (rated as mild) 3-10%) is very low.

In addition, the technique may be more cost-effective for patients who find it hard to commit to fixed ortho.

My questions are ......

1. Do any fellow Spear members have any experience with this technique?

2. Is the Dahl appliance widely used in the United States?

3. If not, what is the opinion of the technique in the U.S.?

Look forward to hearing from you,

Stuart