I have been clenching bad while asleep.i wear a lower bitesplint&am noticing small vertical cracks on sides of my lower first molar.should i worry?

need to see dentist: If you are a grinder and noticed crack should get it evaluated by dentist..Before the crack worsens and starts causing symptoms so your dentist can treat after evaluation.

Molar cracks: The cracks could have been there b4 you got the bite splint and now are enlarging see a dentist for evaluation a crown/cap may be neccessary.

Perhaps: Go back to the practitioner who made your splint. He/she has baseline records. Ask if an Orthodontic consultation is in order. A splint treats symptoms, not the cause of your clenching. May be time for a different focus.

There before?: Were you aware of the vertical cracks/fissure lines before. Check with your dentist. May have to modify the splint