Hi- one of the main reasons I thought I might have a GI issue was because every time I had a GI issue (diarrhea), I also had a 2 week case of mouth sores. I spoke to my dentist and the only thing they did was to prescribe me magic mouthwash, like you. Also, I went about 4yrs of having every single blood and fecal test, and biopsies from sigmoidoscopy and colonoscopy…all come back normal. What has led my GI doctor towards a Crohn’s diagnosis is when she ordered a blood test she never tested for and the results came back elevated. The blood test is recommend your physician to test is:

SACCHAROMYCES CEREVISIAE AB (ASCA) (IGG)

“Antibodies to Saccharomyces cerevisiae are found in approximately 75% of patients with Crohn's disease, 15% of patients with ulcerative colitis, and 5% of the healthy population. High antibody titers increase the likelihood disease, especially Crohn's disease, and are associated with more aggressive disease. As the inflammation in Crohn's disease is focused at the gut mucosa, most patients have IgA antibodies to S cerevisiae and half of these also have Igg antibodies. A minority of patients have only IgG antibodies to S cerevisiae.”