title: Demonstrations of de-and remineralization mechanism as revealed in synthetic auditory ossicle (Apaceram) of rats by laser-Raman spectrometry.
abstract: In investigations of the process of bone destruction caused by chronic otitis media complicated with cholesteatoma, we proposed previously a hypothesis to explain its mechanism. In the present study, we substitute a synthetic auditory ossicle (Apaceram) for the bone to simplify the model system of experiments for our hypothesis. Its process was studied on a model simulation in vitro, in vivo and clinically at molecular level, using laser-Raman spectrometry. An increase of conductivity in both the saline solution and double-distilled water immersed Apaceram indicated demineralization depending on time lapse. The process of demineralization was revealed by the Raman spectral profiles as shown by narrowing a half-peak breadth (p < 0.01) of v1 signal (PO4(3-), 960 cm-1) and the disappearance of the shoulder at circa 950 cm-1 on the Apaceram surface implanted for 6 months. On the other hand, the process of remineralization was revealed in vivo by the spectral profiles: 1) a broader half-peak breadth (p < 0.01) of v1 signal on the Apaceram surface implanted for 10 months than that implanted for 6 months; 2) a weak reappearance of the shoulder at ca. 950 cm-1 on the Apaceram surface after 10 months; 3) four signals (v1 through v4) of PO4(3-) on the HOAP observed for inside the Apaceram shaft and 4) a weak v1 signal on both the granular fluorescent substance in the clinical case and the high density area of subcutaneous tissue after contact with the Apaceram in rats for 3 months. Judging from these investigations, it is proposed that the mechanism of bone destruction associated with cholesteatoma is a form of de- and remineralization.
authors: Division of Clinical Otology, University Hospital, School of Medicine, University of Tokushima, Japan.
authors: K
authors: K
authors: Ohsaki
authors: A
authors: A
authors: Shibata
authors: S
authors: S
authors: Yamashita
authors: M
authors: M
authors: Oe
authors: K Q
authors: KQ
authors: Wang
authors: P C
authors: PC
authors: Cui
authors: Q
authors: Q
authors: Ye
mesh_terms: D000818:Animals; D018488:Bone Demineralization, Pathologic / Q000209:etiology* / Q000378:metabolism; D002114:Calcinosis / Q000209:etiology* / Q000378:metabolism; D018424:Cholesteatoma, Middle Ear / Q000150:complications* / Q000378:metabolism; D004195:Disease Models, Animal; D017886:Durapatite / Q000378:metabolism; D004429:Ear Ossicles; D005260:Female; D008954:Models, Biological; D010033:Otitis Media / Q000150:complications* / Q000378:metabolism; D019736:Prostheses and Implants; D051381:Rats; D017208:Rats, Wistar; D013059:Spectrum Analysis, Raman
chemical_list: D017886:Durapatite