AbstractTwo different types of hydroxylapatite ceramics were examined histologically to assess their effects on the healing of standardized bone defects drilled in the mandibular bone of beagles. After 40 days both materials were totally enclosed by newly‐formed bone, but only the defects filled with micro‐porous hydroxylapatite were found to show bone incorporation which is a good indicator of implant stability. These results suggest that the physio‐chemical similarities between the micro‐porous hydroxylapatite and native bone may promote effective bone incorporation which can increase the stability of i