Can oral thrush cause dental problems/cavities?

Definitely, no. While it is common for oral thrush to grow on the cheek and tongue, it is not so common to find Candida in plaque and there is no relation to tooth decay.
Thrush. Thrush overgrowth can affect the enamel and finally cause cabities.
Tissue problems. Oral thrush (Candida Albicans} is a fungus that can cause tissue related problems and should be treated. See a dentist asap.
Thrush. Yes, but the more important question is why someone who is healthy getting thrush? decreased immunity , diabetes , antibiotic use can all cause thrush .