Widely varying prevalence rates of oral lesions in patients with Crohn's disease have been reported, ranging from 0.5% to 37%. These manifestations may coincide with or precede intestinal symptoms. Oral manifestations can be classified as specific lesions, when macroscopic examination shows similar changes to those observed endoscopically in the intestine, and non-specific lesions including aphthous ulcerations. The most frequently observed oral lesions are oedema, ulcers and hyperplastic lesions on the buccal mucosa. In most patients these lesions are asymptomatic, however, some patients may experience discomfort. In this review we describe the most relevant oro-dental manifestations observed in patients with Crohn's disease and discuss the potential implications for oro-dental management.