Synthetic hydroxyapatite-based integrated orbital implants - A study of consecutive 25 human trials ( Study conducted by Dr.Santanu Mitra at Disha Eye Hospitals, Barrackpore , West Bengal , India in 2002-2003 )

Purpose Orbital implants made up from different materials ie. Metal, glass, polymer and coralline hydroxyapatite (HAP) have been introduced to fill the orbital volume of the extracted eye which have been eventually disreputed due to high exclusion rate and/or other associated disadvantages. Currently, synthetic hydroxyapatite based spherical orbital implants have been used after evisceration and enucleation surgery. After completion of fibro-vascularisation, these implants are often drilled and pegged if necessary for better fixation and motility of the artificial eye. The overall motility as well as the degree of fibro-vascularisation of these implants however, depends on the porosity, pore size and its distribution which need to be optimized. In this study, two different models of the porous orbital implants with 75% porosity with pore size range from 100 to 300 micron have been developed from synthetic hydroxyapatite (HAp). The efficacy of these implants has been evaluated based on the clinical results, degree of vascularization, and quantification of the implant/prosthesis movement.