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Ocular prosthesis is either a readymade stock shell or custom made prosthesis (CMP). Presently, there is no other technology available, which is either superior or even comparable to the conventional CMP. The present study was designed to fabricate ocular prosthesis using computer aided design (CAD) and rapid manufacturing (RM) technology and to compare it with custom made prosthesis (CMP). The ocular prosthesis prepared by CAD was compared with conventional CMP in terms of time taken for fabrication, weight, cosmesis, comfort, and motility. Two eyes of two patients were included. Computerized tomography scan of wax model of socket was converted into three dimensional format using Materialize Interactive Medical Image Control System (MIMICS)software and further refined. This was given as an input to rapid manufacturing machine (Polyjet 3-D printer). The final painting on prototype was done by an ocularist. The average effective time required for fabrication of CAD prosthesis was 2.5 hours; and weight 2.9 grams. The same for CMP were 10 hours; and 4.4 grams. CAD prosthesis was more comfortable for both the patients. The study demonstrates the first ever attempt of fabricating a complete ocular prosthesis using CAD and rapid manufacturing and comparing it with conventional CMP. This prosthesis takes lesser time for fabrication, and is more comfortable. Studies with larger sample size will be required to further validate this technique.

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In the present study, aluminium alloy (A380) composites containing 3, 6, 9 and 12 weight percentage of fl y ash particles were fabricated by liquid metallurgy technique. Three different size ranges of fl y ash particles (50 -75 μ m, 75 -103 μ m and 103 -150 μ m) were used. The composites were evaluated for hardness, tensile strength, density, dry sliding wear and frictional behaviour. Pin-on disc apparatus was used to conduct wear tests at loads of 20, 30 and 40 N at a sliding speed of 3 m/s for a constant period of 10 min. Results showed that hardness, ultimate tensile strength, wear resistance and coeffi cient of friction were superior in composites reinforced with coarse fl y ash particles (103 -150 μ m) compared to composites with fi ne particles. The hardness, ultimate tensile strength and wear resistance increased, whereas the coeffi cient of friction and density decreased with the increase in weight percentage of fl y ash. Wear resistance and coeffi cient of friction decreased with increase in applied load. Scanning electron microscope investigations of worn-out samples were carried out to study the progress of wear.

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