Teenagers in parts of Caithness and Sutherland are having to make 200 mile-long (322 km) round trips for orthodontic treatment in Inverness.
The dental care is not available on the NHS in the areas.
Campaigners claim 950 orthodontic appointments each year involved local young people, and the trips had an impact on their exam revision time.
NHS Highland said it, like other health boards, was experiencing a shortage of orthodontic consultants.
It said it was working with the North of Scotland Planning Group, which is a collaboration between it and Grampian, Orkney, Shetland, Tayside and Western Isles health boards, on finding a solution.