title: A histopathological study of the role of periodontal ligament tissue in root resorption in the rat.
abstract: Whether periodontal ligament (PDL) tissue is capable of inducing root resorption was examined. The distal root of the rat molar was sectioned at the furcation and the PDL tissue removed from the root (non-PDL group, n=40). The distal root with the PDL intact was also prepared (PDL-intact group, n=40). The roots were transplanted into the dorsal skin of the rat. On the 1st, 3rd, 5th, 7th, 10th, 14th, 21st or 28th day after transplantation, the roots were removed together with surrounding dorsal subcutaneous tissue and were fixed, demineralized and embedded in paraffin. Serial sections from each block were stained with haematoxylin and eosin or by the tartrate-resistant acid phosphatase (TRAP) method to observe root-resorbing cell formation. Cyclo-oxygenase-2 (COX2) was also detected immunohistologically to examine prostaglandin E(2) production. On the 7th day after transplantation, multinucleated root-resorbing cells with TRAP were observed in the PDL-intact group. The number of TRAP-positive cells peaked on the 10th day after transplantation. COX2-positive cells were observed in PDL during the early experimental stages. No root resorption was seen in the non-PDL group. These results suggest that PDL tissue is involved in the formation of root-resorbing cells and root resorption.
authors.affiliation: Department of Periodontology, Nagasaki University School of Dentistry, 1-7-1 Sakamoto, Nagasaki, 852 8588, Japan.
authors.forename: C
authors.initials: C
authors.lastname: Shiraishi
authors.forename: Y
authors.initials: Y
authors.lastname: Hara
authors.forename: Y
authors.initials: Y
authors.lastname: Abe
authors.forename: T
authors.initials: T
authors.lastname: Ukai
authors.forename: I
authors.initials: I
authors.lastname: Kato
mesh_terms: D000135:Acid Phosphatase; D000704:Analysis of Variance; D000818:Animals; D051546:Cyclooxygenase 2; D015232:Dinoprostone / Q000096:biosynthesis; D007527:Isoenzymes / Q000096:biosynthesis; D008297:Male; D023421:Models, Animal; D010010:Osteoclasts / Q000502:physiology; D010513:Periodontal Ligament / Q000378:metabolism / Q000503:physiopathology*; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis; D051381:Rats; D011917:Rats, Inbred Lew; D012391:Root Resorption / Q000503:physiopathology*; D000071681:Tartrate-Resistant Acid Phosphatase; D014092:Tooth Root / Q000637:transplantation
chemical_list: D007527:Isoenzymes; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase; D015232:Dinoprostone