Merthyr dentist on long distance patient from Pembrokeshire
Only 37% of dentists in Wales are accepting new NHS patients, according to the Welsh Liberal Democrats.
The party also criticises waiting lists for new patients wanting a dentist, which was six years at one practice.
The British Dental Association said ministers needed to give more direction to health boards over dental spending.
The Welsh government said there had been improvements but recognised access to NHS dentists was "difficult in some areas".
Huw Jones, a dentist and practice owner in Merthyr Tydfil, says he has a regular patient who travels from Solva in Pembrokeshire, 96 miles away.