Purpose: Recently, a fully Nanocrystalline Hydroxyapatie (NHA) paste has been introduced for augmentation procedures in osseous defects and is attracting increasing interest in medicine and dentistry. The purpose of the present study was to assess and compare the pulp response of pig primary teeth after capping with NHA and formocresol in pulpotomy and NHA and calcium hydroxide in direct pulp capping.
Methods: Forty teeth of two 4-month old pigs were pulpotomized and capped with these materials. Four weeks later, the animals were euthanized and the specimens were prepared for histological examination.
Results: In the pulpotomy groups, there was a significant difference between NHA and FC in terms of pulp response, hard tissue formation and normal pulp tissue preservation. In the direct pulp capping groups, there was no significant difference between NHA and Ca(OH)2 in terms of criteria mentioned above.
Conclusions: The results of the present histological study show that, in the short term and in non-carious pig teeth, NHA appears to be biocompatible and provokes no moderate or severe inflammatory reaction in pulp tissue in both pulpotomy and direct pulp capping treatments.