Calcium phosphate ceramics are used in the substitution of injured or damag
ed bones. Nevertheless, the behaviour of these materials, and in particular
, the mechanisms guiding their interface response in physiological environm
ent is still unknown. This work describes the construction of hydroxyapatit
e and tricalcium phosphate electrodes used to determine the interface poten
tial behaviour of these materials in a simulated body fluid, in a pH range
corresponding to the Variation observed in human body injuries, at ambient
and physiological temperatures. These measurements are associated with the
adsorption/desorption of ions from the materials. The results show that hyd
roxyapatite and tricalcium phosphate have similar behaviour in that they re
ach an interface potential equilibrium state faster when the solution pH is
decreased and the temperature increased. This behaviour may be attributed
to their ability to form a calcium-rich layer and is relevant to their qual
ity as implantable materials. (C) 1998 Published by Elsevier Science Ltd. A
ll rights reserved.