The incidence of inflammatory bowel diseases (IBD) - Crohn's disease (CD) and 
ulcerative colitis (UC) - has been increasing on a global scale, and 
progressively, more gastroenterologists will be included in the diagnosis and 
treatment of IBD. Although IBD primarily affects the intestinal tract, 
extraintestinal manifestations of the disease are often apparent, including in 
the oral cavity, especially in CD. Specific oral manifestations in patients with 
CD are as follows: indurate mucosal tags, cobblestoning and mucogingivitis, deep 
linear ulcerations and lip swelling with vertical fissures. The most common 
non-specific manifestations, such as aphthous stomatitis and angular cheilitis, 
occur in both diseases, while pyostomatitis vegetans is more pronounced in 
patients with UC. Non-specific lesions in the oral cavity can also be the result 
of malnutrition and drugs. Malnutrition, followed by anemia and mineral and 
vitamin deficiency, affects the oral cavity and teeth. Furthermore, all of the 
drug classes that are applied to the treatment of inflammatory bowel diseases 
can lead to alterations in the oral cavity due to the direct toxic effects of 
the drugs on oral tissues, as well as indirect immunosuppressive effects with a 
risk of developing opportunistic infections or bone marrow suppression. There is 
a higher occurrence of malignant diseases in patients with IBD, which is related 
to the disease itself and to the IBD-related therapy with a possible oral 
pathology. Treatment of oral lesions includes treatment of the alterations in 
the oral cavity according to the etiology together with treatment of the primary 
intestinal disease, which requires adequate knowledge and a strong cooperation 
between gastroenterologists and specialists in oral medicine.