[A PhD completed. The use of periodontal ligament fibroblasts in research on fibrodysplasia ossificans progressiva].

Fibrodysplasia ossificans progressiva is a rare hereditary bone disease characterized by so-called heterotopic bone formation: the formation of new bone in areas of the body where bone normally never develops. Due to the formation of this heterotopic bone, approximately 70% of patients eventually also experience limitations in the mobility of the jaw, which in many cases results in a significantly reduced maximum mouth opening. Because of these jaw-related problems, teeth are sometimes extracted in these patients. Periodontal ligament fibroblasts can be isolated from these teeth, cells that play a role in both bone formation and bone breakdown. The location in the jaw area where heterotopic bone formation takes place determines the effect on maximal mouth opening. In addition, periodontal ligament fibroblasts are shown to be very useful for (fundamental) research into exceptional bone diseases such as fibrodysplasia ossificans progressiva.