What if the toenail thickens?

Toenail thickening, to see these two reasons: the first is a history of trauma, local before the relatively violent impact, resulting in nail bed damage, and then nail bed growth will be affected, will show nail deformation thickening. The second type is nail fungus infection, then nail bed is destroyed, grow out of the nail is abnormal, will show thickening, color yellow or brown, or gradually show some hollow or distal nail shows broken. So which type is caused, to see a doctor first, if necessary, do a fungal smear and culture test to identify.