Effect of dolomite on the repair of bone defects in rats: histological study.
The aim of the present study was to evaluate histologically and radiographically the tissue response to dolomite [CaMg(CO3)2] and its osteogenic potential in the repair of bone cavities in the calvaria of rats. A bone defect 10 mm in diameter and 1 mm deep was made in the calvaria of male Wistar rats. The defects were filled with dolomite, inorganic bovine bone (positive control), or coagulum (negative control). The animals were euthanized 7, 15, 30, and 60 days after surgery, and specimens were collected for radiographic and microscopic analyses. The bone defects were processed for paraffin embedding and H&E staining. The histological study revealed that dolomite stimulated a moderate inflammatory response, with programmed cell death in the first 15 days, compared to bovine bone which showed a moderate to intense acute response. In the chronic phase, the inflammatory response was characterized by the occurrence of macrophages organized as epithelioid cells in the dolomite group, and giant cells in the bovine-bone group. Fibrosis developed in all three groups; however, encapsulation of the fragments, reabsorption, and osteoconductive activity occurred only in the defects filled with bovine bone. The radiographic analysis showed that the bovine bone was most efficient in the repair of the defects, followed by the dolomite and the coagulum. This study demonstrated that the dolomite stimulated a moderate acute inflammatory response with programmed cell death, and a chronic inflammatory response by means of the phagocytic mononuclear system. Although osteo-conductive activity was not shown, the dolomite favored the repair process, compared to the coagulum group.
Moreschi
Eduardo
E
Department of Pharmacy and Pharmacology, Inflammation Laboratory, University of Maringá, Maringá-PR, Brazil.
Hernandes
Luzmarina
L
Dantas
Jailson Araujo
JA
da Silva
Maria Angélica Raffaini Covas Pereira
MA
Casaroto
Ana Regina
AR
Bersani-Amado
Ciomar Aparecida
CA
D000818:Animals; D001861:Bone Regeneration / Q000187:drug effects*; D001842:Bone and Bones / Q000187:drug effects* / Q000293:injuries; D002119:Calcium Carbonate / Q000494:pharmacology*; D008274:Magnesium / Q000494:pharmacology*; D008297:Male; D010012:Osteogenesis / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar
D002119:Calcium Carbonate; D008274:Magnesium; C028042:calcium magnesium carbonate