BACKGROUND With the increasing use of hydroxyapatite orbital implants, the complication of exposure has become apparent to oculoplastic surgeons. Many kinds of patch grafts, such as sclera, dermis, and hard palate mucosa, have been used to cover exposed hydroxyapatite implants with inconsistent results. In this study, the authors use a newly developed technique, autogenous retroauricular myoper...

Since hydroxyapatite has excellent biocompatibility and bone bonding ability, porous hydroxyapatite ceramics have been intensively studied. However, porous hydroxyapatite bodies are mechanically weak and brittle, which makes shaping and implantation difficult. One way to solve this problem is to introduce a strong porous network onto which hydroxyapatite coating is applied. In this study, porou...

Collagen-hydroxyapatite interfaces compose an important building block of bone structures. While it is known that the nanoscale structure of this elementary building block can affect the mechanical properties of bone, a systematic understanding of the effect of the geometry on the mechanical properties of this interface between protein and mineral is lacking. Here we study the effect of geometr...

A range of crystalline and nano-sized carbonate- and silicate-substituted hydroxyapatite has been successfully produced by using continuous hydrothermal flow synthesis technology. Ion-substituted calcium phosphates are better candidates for bone replacement applications (due to improved bioactivity) as compared to phase-pure hydroxyapatite. Urea was used as a carbonate source for synthesising p...

OBJECTIVES The purpose of this study was to measure and analyze the mechanical properties of several composite materials designed for dental restoration. METHODS The materials were composed of a visible light-curing monomer mixture (either Bis-GMA+TEGDMA or Bis-GMA+HEMA) as a matrix and hydroxyapatite (either microscopic or nanoscopic particles) as a reinforcing filler. The surface of the hyd...

The healing process after implantation of sintered bone in the rat parietal bone was compared with that of synthetic hydroxyapatite using both scanning electron and light microscopy. The results showed that the differences between the sintered natural bone and the synthetic hydroxyapatite implantations were in the states of bone union and the bioresorbability of the implanted materials, even th...

Crab's shells of Portunus pelagicus species were used as raw materials for synthesis of hydroxyapatite were used for protection against demineralization of teeth. Calcination was conducted to crab's shells of Portunus pelagicus at temperature of 1000°C for 5 hours. The results of calcination was reacted with (NH4)2HPO4, then dried at 110°C for 5 hours. Sintering was conducted to results of prec...

Poly (2-hydroxy ethyl) methacrylate (PHEMA) is a polymer that can be carboxymethylated to induce calcification on its surface. This mimics the calcification of bone matrix since the polymer surface induces the deposit of large hydroxyapatite calcospherites. We investigated the effect of Sr on hydroxyapatite crystals developed on PHEMA pellets. Pellets were incubated for 1 week in a synthetic bo...

AIMS To document the long term experience of bone derived hydroxyapatite orbital implants and compare results using scleral wrapped implants with those not using sclera. METHODS This retrospective case series reviewed the long term follow up of 118 patients with 120 eyes which had undergone enucleation and bone derived hydroxyapatite orbital implant insertion at Dunedin Hospital from 1977 unt...

OBJECTIVE The objective of this study is to develop a method for selective detection of the calcific (hydroxyapatite) component in human aortic smooth muscle cells in vitro and in calcified cardiovascular tissues ex vivo. This method uses a novel optical molecular imaging contrast dye, Cy-HABP-19, to target calcified cells and tissues. METHODS A peptide that mimics the binding affinity of ost...