Defence reaction in dental pulp after pulp capping and partial pulpectomy in dogs.

The dental pulp was capped indirectly or directly, or partial vital pulpectomy was performed on the 12 functionally most important teeth of 24 beagle dogs. For pulp capping, calcium hydroxide was used, followed by zinc phosphate as a lining, and the preparation was restored with amalgam or composite material. Histological sections were prepared and examined for degree and type of pulp inflammation (hyperaemia, pulpitis, necrosis or gangrene). Degenerative changes of dental pulp (vacuolation, calcification, amyloid or hyaline changes) were also determined. For indirect pulp capping the width of predentine in crown and root dental pulp was measured, and for direct pulp capping and partial pulpectomy (vital pulpotomy) the width and quality of the dentinal bridge were graded. The radical method of partial vital pulpectomy of the coronal part of the dental pulp in dogs produced better quality and continuity of the dentinal bridge than the less radical method of direct pulp capping. This was particularly obvious in small single root teeth such as incisors.