Effect of an oily calcium hydroxide suspension (Osteoinductal) on healing of intrabony periodontal defects. A pilot study in dogs.

The aim of the present study was to evaluate histologically in dogs the effect of treating intrabony defects with an oily calcium hydroxide suspension (OCHS). Intrabony defects were surgically created bilaterally at the distal aspects of the maxillary first premolars and at the mesial aspects of the third premolars in two mongrel dogs. Subsequently, the defects were randomly treated with (a) access flap surgery followed by the application of an OCHS or (b) access flap surgery alone. After 8 weeks of healing, the animals were killed. Dissected blocks containing the experimental specimens were fixed in formalin, decalcified in EDTA, and embedded in paraffin. The formation of new cementum and bone was assessed histomorphometrically. In the control group, healing was predominantly characterized by the formation of a long junctional epithelium along the root surface and limited periodontal regeneration at the most apical part of the defect. The OCHS-treated defects consistently revealed periodontal regeneration (i.e., new periodontal ligament, new cementum with inserting collagen fibers, and new bone). Within the limits of the present study, it can be concluded that OCHS may favor periodontal regeneration in acute-type intrabony periodontal defects.