The present study compares the bone response to commercially pure titanium screws with two different degrees of surface roughness. Implants blasted with 25- and 250-µm particles of aluminum oxide were placed in rabbit tibiae after the surface roughness of the implants had been measured. After 4 weeks, there was a significantly higher bone-to-metal contact for implants blasted with 25-µm particles compared to those blasted with 250-µm particles. The present study indicates that a highly increased surface roughness compared to a moderately increased one is a short-term disadvantage for bone tissue. Schlagwörter: histomorphometric evaluation, mechanical evaluation, surface roughness characterization, three dimensional