Objective: Evaluate histologically and compare the inflammatory pulp response following direct pulp capping of mechanically exposed dogs' teeth with: Ca(OH)2 base Dycal, UltraBlend Plus and TheraCal LC, at different time intervals.
Subjects and methods. A total of 54 permanent teeth of six healthy dogs were used. They were randomly divided into three groups (n=18) according to pulp capping material used. Group I: Dycal, Group II: UltraBlend Plus (UBP) and Group III: TheraCal LC. All cavities were restored with Riva LC Resin Modified Glass Ionomer. Each group was subdivided into three subgroups according to storage time (n=6) at time intervals of 1 week, 1 month and 3 months. Control samples (3 teeth) were added representing normal untouched teeth for evaluating histological features of normal pulp. Paraffin sections were prepared stained with H&E then examined under light microscope for histologic evaluation of the inflammatory cell response according to the scoring system suggested by Nowicka et al.
Results. Theracal specimens showed the lowest inflammatory score among the three capping materials in one week period followed by UBP and Dycal respectively .The inflammatory score by the end of third month improved for all materials. No inflammation was detected in Theracal specimens by the end of third month.
Conclusions: Subsiding of inflammation over the study period is a sign of biological acceptance of the materials used in this investigation. Theracal is superior to Dycal and UBP for pulp capping of mechanically exposed human teeth, it can be used as an effective direct pulp capping material.