Influence of the restoration after pulpotomy on the strength of electrical stimulus reaching the pulp space: An in vitro investigation

INTRODUCTION: The study evaluated the influence of coronal restoration after pulpotomy on the strength of electrical stimulus reaching the radicular pulp using an electric pulp test (EPT). MATERIALS AND METHODS: The pulp tissue from ten freshly extracted mandibular premolar teeth was removed and replaced with an electroconductive gel. The cathode probe of Powerlab was inserted into the pulp space and the anode probe was attached to the EPT handpiece. The EPT probe coated with electro-conducting material was positioned in the middle third of the buccal crown surface. The EPT stimulus reaching the pulp space of an intact tooth at 40 numerical readings was recorded. The tooth was removed from model and endodontic access was made. The 2-mm thick mineral trioxide aggregate was placed at the cementoenamel junction followed by composite resin restoration. The experimental setup was re-established and postpulpotomy EPT stimulus data were recorded. The data collected were compared using the Wilcoxon signed-rank test. RESULTS: There was a statistically significant difference (P = 0.038) between observed between the strength of EPT stimulus reaching the pulp space in prepulpotomy (mean 91.18 ± 101.02 V and median 25.79 V) and postpulpotomy (mean 58.49 ± 77.13 V and median 13.75 V) tooth samples. CONCLUSION: The placement of the restoration and pulp capping agent after pulpotomy dampens the strength of EPT stimulus reaching the pulp canal space.