The only anatomical landmark experiencing migration is the gingival margin in a coronal direction. In a gingival pocket, no destruction of the connective tissue fibers (gingival fibers) or alveolar bone occurs. This early sign of disease in the mouth is completely reversible when the etiology of the edematous reaction is eliminated and frequently occurs without dental surgical therapy. However, in certain situations, a gingivectomy is necessary to reduce the gingival pocket depths to a healthy 1–3 mm. Periodontal pocket
As the original sulcular depth increases and the apical migration of the junctional epithelium has simultaneously occurred, the pocket is now lined by pocket epithelium (PE) instead of junctional epithelium (JE). To have a true periodontal pocket, a probing measurement of 4 mm or more must be clinically evidenced. In this state, much of the gingival fibers that initially attached the gingival tissue to the tooth have been irreversibly destroyed. The depth of the periodontal pockets must be recorded in the patient record for proper monitoring of periodontal disease. Unlike in clinically healthy situations, parts of the sulcular epithelium can sometimes be seen in periodontally involved gingival tissue if air is blown into the periodontal pocket, exposing the newly denuded roots of the tooth. A periodontal pocket can become an infected space and may result in an abscess formation with a papule on the gingival surface. Incision and drainage of the abscess may be necessary, as well as systemic antibiotics; placement of local antimicrobial delivery systems within the periodontal pocket to reduce localized infections may also be considered.
Bowel infarction or gangrenous bowel represents an irreversible injury to the intestine resulting from insufficient blood flow. It is considered a medical emergency because it can quickly result in life-threatening infection and death. Any cause of bowel ischemia, the earlier reversible form of injury, may ultimately lead to infarction if uncorrected. The causes of bowel ischemia or infarction include primary vascular causes (for example, mesenteric ischemia) and other causes of bowel obstruction. Causes
Primary vascular causes of bowel infarction, also known as mesenteric ischemia, are due to blockages in the arteries or veins that supply the bowel. Types of mesenteric ischemia are generally separated into acute and chronic processes, because this helps determine treatment and prognosis.Bowel obstruction is most often caused by intestinal adhesions, which frequently form after abdominal surgeries, or by chronic infections such as diverticulitis, hepatitis, and inflammatory bowel disease. The condition may be difficult to diagnose, as the symptoms may resemble those of other bowel disorders. Bowel volvulus describes a specific form of bowel obstruction, where the intestine and/or mesentery are twisted, resulting in ischemia. Management
An infarcted or dead intestinal segment is a serious medical problem because intestines contain non-sterile contents within the lumen. Although the fecal content and high bacterial loads of the intestine are normally safely contained, progressive ischemia causes tissue breakdown and inevitably leads to bacteria spreading to the bloodstream.