The ability ofbonegraft substitutes to promote newbone formation has been increasingly used in the medical field to repair skeletal defects or to replace missingbonein a broad range of applications in dentistry and orthopedics. A common way to assess such materials is via micro computed tomography (-CT), through the density information content provided by the absorption of X-rays. Information on the chemical composition of a material can be obtained via Raman spectroscopy. By investigating abonesamplefrom miniature pigs containing thebonegraft substitute Bio Oss®, we pursued the target of assessing to what extent the density information gained by -CT imaging matches the chemical information content provided by Raman spectroscopic imaging. Raman images and Raman correlation maps of the investigatedsamplewere used in order to generate a Raman based segmented image by means of an agglomerative, hierarchical cluster analysis. The resulting segments, showing chemically related areas, were subsequently compared with the -CT image by means of a one-way ANOVA. We found out that to a certain extent typical gray-level values (and the related histograms) in the -CT image can be reliably related to specific segments within the image resulting from the cluster analysis.