Retraction Note: Bioactivity measurement of commercially pure titanium processed by micro-electric discharge drilling

The surface modification is a pivotal step in the field of the biomedical implant in order to improve its biomedical characteristics. A number of methods can be adopted to improve surface characteristics like coating, evaporation, sputtering, and ion implantation. The surface of any material can also be improved by machining. In the present work, an electric discharge drilling (EDD) was used for the development of quality holes on any conductive material regardless of its hardness. In the present research, commercially pure titanium (CPTi) was drilled for the development of microhole using the EDD. The effect of microholes on the apatite formation and weight gain was determined. The apatite formation was measured in the presence of simulated body fluid (SBF) after 7, 14, and 21 days of immersion. The temperature and pH during the apatite formation were 37 °C and 7.4, respectively. It was found that after the development of microholes, the quantity of apatite formation increases. On the contrary side on the normal CPTi material (without drilling), an insignificant apatite formation was observed. However, after drilling, the elements of calcium and phosphate were observed ever after 4 days of immersion in SBF. The surface area of the apatite formation increases by 24% after the development of microholes. Scanning electron microscopy (SEM) revealed the microstructure of the drilled surface before and after the immersion of CPTi in SBF. In addition, it was observed that with the increase in the number of holes and immersion period, the apatite formation increases.