title: Radiographic and microscopic evaluation of subperiosteally implanted blocks of hydrated and hardened alpha-tricalcium phosphate in rabbits.
abstract: Tissue response to preformed tricalcium phosphate (TCP) blocks prepared from alpha-tricalcium phosphate (alpha-TCP) powder by hydration and hardening at 80 degrees C was studied by implanting them subperiosteally on the buccal aspect of the mandible in rabbits. X-ray diffraction of the alpha-TCP powder showed a typical pattern of TCP, whereas a mixed pattern of TCP and hydroxylapatite was obtained after hydration and hardening. The radiographic findings at 4 weeks showed a tendency to bony union of the TCP block with the underlying bone. Microscopically, new bone that was being formed extensively from the underlying bone surface and filling the space between the block and bone at 4 weeks gradually changed into lamellar bone. There was no evidence of resorption of the TCP block throughout the experiment. The tissue response was essentially consistent with that to hydroxylapatite particles studied under similar conditions in our laboratory. It was concluded that the hydration and hardening of alpha-TCP powder may provide an implant block with a desirable contour that does not interfere with bone formation.
authors.affiliation: First Department of Oral and Maxillofacial Surgery, School of Dentistry, Niigata University, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Nagase
authors.forename: R B
authors.initials: RB
authors.lastname: Chen
authors.forename: Y
authors.initials: Y
authors.lastname: Asada
authors.forename: T
authors.initials: T
authors.lastname: Nakajima
mesh_terms: D000818:Animals; D001861:Bone Regeneration; D002130:Calcium Phosphates; D008334:Mandible / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000502:physiology*; D008422:Materials Testing; D019736:Prostheses and Implants; D011817:Rabbits; D011859:Radiography; D013718:Tensile Strength
chemical_list: D002130:Calcium Phosphates; C485828:alpha-tricalcium phosphate; C485830:tetracalcium phosphate; C485838:calcium phosphate, monobasic, anhydrous; C020243:calcium phosphate; C485829:calcium phosphate, dibasic, anhydrous