This paper reports the preliminary results on the morphology of low porosity hydroxyapatite scaffold and its compatibility as a substrate for osteoblast cells. Although having low porosity, the hydroxyapatite scaffold was found to be capable of sustaining cell growth and thus assisting bone ingrowth. Due to the low porosity nature, the scaffold provides higher strength and therefore more suitable for applications with load-bearing requirements such as spinal spacer. The hydroxyapatite scaffolds are prepared via powder processing techniques, using a combination of wet mixing, powder compaction, and sintering processes. The scaffold porosity is estimated via image analysis and micro-CT, which detect porosity level of approximately 16% and pore size of 13？μm. Cell culture investigation demonstrates that the hydroxyapatite substrate is able to provide favourable cell attachment and collagen matrix production, as compared to the commonly used cell culture control substrates. These results indicate that despite the low porosity in the hydroxyapatite scaffolds, they do not hinder being a preferred substrate to provide conducive environment osteoblast cell growth. 1. Introduction Over the years, many healthcare products related to the improvement of a person’s wellbeing as one ages have seen an increase in demand [1]. One of the examples is the use of an artificial implant to replace dysfunctional body parts or to assist the healing process of a diseased body part. Artificial bone implantation has an advantage over the use of autograft (implant sourcing from the same individual) or allograft (implant sourcing from different individual), mainly due to the limited source of bony parts that can be removed and reimplanted. Secondly, autograft and allograft require secondary operations to perform organ removal from the donor site and implantation into the targeted site. Therefore, artificial materials have been researched for bony implant purposes. In the context of bone-related diseases, hydroxyapatite (HA) has been widely used for bone replacement material due to its similarity in composition with respect to bone. The composition of bone mineral is comparable to sintered HA. The mineral component of bone is a biological apatite, where carbonate substitutes phosphate ions by about 3–5？wt.% [2]. HA has been reported to have bioactivity nature and thus assists integration and interaction of osteoblast with the implants [3]. Apart from its compatibility with osteoblast, HA surface is biocompatible with several other types of cells, such as macrophages, fibroblasts,
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