Adverse effects of human pulps after direct pulp capping with the different components from a total-etch, three-step adhesive system

Objectives The objective was to evaluate the response of human pulps capped with different components from a total-etch three-step adhesive system. Methods Direct pulp capping was performed in 25 caries-free human premolars scheduled for extraction due to orthodontic treatment. The teeth were randomly divided in five groups, and capped with the following materials: Group 1—acid+primer+adhesive were used as recommended; Group 2—only primer was applied; Group 3—only bonding resin (light-cured for 10 s); Group 4—only composite resin (light-cured for 40 s); Group 5—calcium hydroxide. After capping, all teeth were restored with ScotchBond Multi Purpose Plus and Z-100 was placed incrementally. After 60 days, the teeth were extracted and processed for light microscopic examination (H/E) according to a histological score system. These were subjected to non-parametric tests (α<0.05). Results Overall, the histological features showed that groups 1–4 were quite similar and inferior to group 5. In groups 1–4 the pulp response varied from acute inflammatory cell infiltrate with varying degrees to necrosis. The groups 3 and 4 showed a trend towards better pulp response, since a normal connective tissue could be observed in more than half of the sample. All teeth from group 5 showed normal connective tissue below an amorphous dentin bridge. Significance Adhesive components (primer or adhesive) as well as a composite should be avoided for pulp capping. Ca(OH)2 should be the first choice for pulp capping.