A. Rosenberg et al., SHOULD TITANIUM MINIPLATES BE REMOVED AFTER BONE HEALING IS COMPLETE, International journal of oral and maxillofacial surgery, 22(3), 1993, pp. 185-188
A prospective study of 32 patients was performed to analyze black pigm
entation in the soft tissue covering titanium miniplates. This soft ti
ssue was compared with the soft tissue covering Champy(R) stainless st
eel plates. All plates were removed 8 months after application. Macros
copically visible pigmentation was found in 25.6% of the soft tissue c
overing titanium miniplates and in none of the soft tissue covering Ch
ampy stainless steel plates. Microscopically visible pigmentation was
found in 71.8% of the soft tissue covering titanium miniplates and in
65.3% of the soft tissue covering Champy stainless steel plates. Energ
y-dispersive x-ray analysis of the soft tissue covering titanium minip
lates revealed only the presence of titanium dioxide. In the soft tiss
ue near Champy stainless steel plates, chromium, nickel, iron, and mol
ybdenum were found. Electron microscopy showed titanium dioxide to be
mainly deposited between the collagen fibers, whereas stainless steel
particles were mainly found in giant cells.