The Research Progress of Platelet-Rich Fibrin Applications in the Orthodontic Treatment

Abstract

Either the alveolar bone defects or the severe absorbed alveolar bone led by the teeth extraction could have an effect on the orthodontic teeth movement. Guided bone generation technique has supplied a new method for the above clinical difficulty. Platelet-Rich Fibrin has been reported in the orthodontics and clinical researches because of its obvious osteogenic property. This paper was to describe the newly applications of Platelet-Rich Fibrin in orthodontic clinic. In the orthodontic clinic, the alveolar bone defects or the height and the decreased width of alveolar bone always occurred due to the common reasons such as tumor, inflammation, the early loss of teeth, extraction or cleft lip and palate, which would have negative effect on the orthodontic teeth movement. For example, the teeth would not move or have a lot of difficulties in moving, the roots of teeth could be absorbed and the alveolar bone around the teeth would be resorbed 1. The above complications would jeopardize stability of the orthodontic treatment results. Nowadays, the development of Guided Bone Regeneration offered a new method to solve the above mentioned difficulties. Platelet-Rich Fibrin has been more noticed in the bone reconstruction because of its obvious osteoinducivity and osteoconductivity properties. At present, there are many studies about Platelet-Rich Fibrin used in the orthodontic fundamental researches and clinical application. This paper was to describe the newly applications of Platelet-Rich Fibrin in orthodontic clinic. The Influence on Teeth Movement Made by Alveolar Bone Changes after Teeth Missed After tooth extraction, the rest alveolar bone would be remodeled and absorbed because of lacking the normal teeth physiological stimulation. Schropp et al 2 observed changes taking place following tooth extraction in humans. He reported the width of the alveolar ridge reduced up to 50% during the 12 month observation period after the extraction. This loss corresponded to a buccal-lingual change in dimension of 4.5 to 6.1 mm. The finding that approximately two thirds of this reduction occurred within the first 3 months after tooth extraction. Horrowitz et al 3 have reported that at the first 3months, the buccal alveolar resorption percent was about 56%, the lingual alveolar resorption percent was about 30%, the buccal resorprion was obvious larger than the lingual alveolar resorption percent. Misch 4 proposed that the loss of crestal bone height and width of the buccal plate after tooth extraction is partially due to the constriction of the blood clot in the alveolus, and the remodeling of the labial cortical plates in response to inadequate blood supply after the extraction, which is consistent with the results make by Horrowitz. The vertical alveolar bone resorption was on average 0.5 to 0.9mm. The changes of the height and wodth of alveolar bone after teeth were missed increased the difficulties of the orthodontic teeth movement. Lindskog Stokland B et al 5 have reported that when the teeth moved to the edentulous area, two situations would can be seen. One was that the teeth moved slowly and the buccal bones would be absorbed. The other situation was that when the teeth contacted the buccal bones, the resorption incidence of lateral roots on the pressure side of orthodontically moved teeth was about 50%. After one year retention, the resorpted roots would be repaired by itself potential repair ability.