Oral ulcers are one of the most common mucosal lesions seen in different locations in the oral cavity. Most of these ulcers will resolve within two weeks. However, chronic ulcers remain problematic in the way they are managed and investigated for possible etiological factors. Viral infections, gastrointestinal disorders, blood diseases, cancer treatment, local trauma, medications or a combination of more than one factor contribute to oral ulcerations. The terms idiopathic or non-specific oral ulcers are still used when no possible explanation could be found regards the causative factors of the ulcerations. We present a unique case of a completely healthy 45 year old female, where a chronic fistula related to a failed root canal treatment developed into a chronic non-specific ulcer over the period of thirty years. The chronic ulcer resembled a diabetic foot ulcer in both clinical and histopathological pictures. Associated teeth with poor prognosis were extracted. Muco-gingival corrective surgery to close the associated gingival defect as well as a ridge preservation surgery to compensate for the associated bone loss produced excellent healing of both soft and hard tissues.