The effects of BMP and TGF-beta on the wound healing of the pulp

本研究旨在探讨骨形态发生蛋白（BMP）和转化生长因子-β（TGF-β）对牙髓创伤愈合的影响。将该混合物置于髓室近中部分，覆盖上颌第一磨牙近中根的根髓，在放置上述混合物后的第一周，在根尖附近、切断部位和根髓组织的中心区域等不同区域可见炎症和纤维组织形成。牙髓组织中散在分布着与骨组织相似的钙化组织，如在离断处形成屏障，沿着牙根内表面分布，部分随机分布于牙髓组织中，3周时骨组织普遍钙化增多。部分病例根管因骨样组织沉积而变窄，骨样组织形成的数量和分布不一。TGF-β超家族包括许多亚型，rhBMP-2被认为是该家族中与牙髓组织中骨形成相关的最重要的成分。通过使用与胶原混合的rhBMP-2而不是使用从胫骨提取的不溶性部分，我获得了与上述相同的结果。因此，该结果证实rhBMP-2是牙髓组织中骨样组织形成的最重要组分。

The objective of this study is to investigate the effects of both Bone morphogenic proteins (BMPs) and transforming growth factor-beta (TGF-beta) on the wound healing of the pulp.First, the water insoluble fraction extracted from Tibia of rat which contained both BMP and TGF-beta was mixed with saline. This mixture was placed on the mesial portion of the pulp chamber, overlying the radicular pulp of the mesial root of maxillary 1st molar.In the first week after placement of the above mentioned mixture, inflammation and formation of fibrous tissues was seen in different areas such as near the apex, at the site of amputation and the central region of the radicular pulpal tissue.In the 2nd week, calcified tissue which closely resembled bone tissue was seen scatterred in the readicular pulpal tissue, such as at the site of amputation where it formed a barrier, along the inner surface of the root and some randomly in the pulpal tissue.In the 3rd week, bone tissue generally became more calcified. In some cases root canal became narrower due to deposition of bone like tissue.The cases we studied showed varied amount of bone like tissue formation and its distribution. This variability may be attributed to the amount of BMP and TGF-beta used in our study which may have been different from case to case.TGF-beta super family includes many subtypes and rhBMP-2 is supposed to be the most important component of this family in relation to bone formation in the pulpal tissue. I obtained the same results as above by using rhBMP-2 mixed with collagen rather than using insoluble fraction extracted from Tibia. Therefore, this result confirms rhBMP-2 is the most important component in the formation of bone like tissue in the pulpal tissue.