the healthy soft tissue surrounding the natural dentition is composed of the gingiva and alveolar mucosa, which are clearly demarcated into clinically identifiable zones. the free gingiva begins at the gingival margin, which is normally located 1 to 3 mm coronal to the cemento-enamel junction and extends to the base of the gingival sulcus. the attached gingiva refers to the tissue that is firmly bound by sharpey’s fibers to the cementum of the tooth and underlying bone and begins at the base of the gingival sulcus in health—or periodontal pocket in disease—and extends to the mucogingival junction. the apical migration of the gingival margin results in gingival recession, which may lead to root exposure that not only may be aesthetically unacceptable to the patient, but more importantly, is always accompanied by bone loss.