An 18-year-old Caucasian woman has been followed since age 12 years for Ehlers-Danlos syndrome (EDS) with easy bruisability and "cigarette paper scars." Her chief complaint at age 17 years was tooth mobility, especially in the anterior mandible, necessitating the removal of the four incisors. Initial biochemical analysis of cultured skin fibroblasts indicated the presence of pepsin-sensitive type III collagen. Subsequent analysis of cultured skin fibroblasts by the same laboratory and another laboratory found no abnormality in the type III collagen with or without protease treatment. This is in distinction to the finding of abnormal type III collagen in the only two reported patients with EDS and early-onset periodontitis who have had collagen analyses. One of them was diagnosed as EDS type IV and the other as EDS type VIII, although the defects of type III collagen were consistent with EDS type IV. The defect in type III collagen in some patients with early periodontitis and the considerable overlap of the clinical manifestations of EDS types IV and VIII point out the need for further studies of collagen formation and maturation in any patient who has early periodontitis and who has been classified with EDS type IV or VIII.