Int J Oral Biol.  2012 Jun;37(2):77-83.

Effect of Mineral Trioxide Aggregate and Calcium Hydroxide on Reparative Dentin Formation in Rats

• Ra JY
• Lee W
• Kim HJ

Abstract

We investigated the pulpal response to direct pulp capping in rat molar teeth using mineral trioxide aggregate (MTA) and calcium hydroxide (CH). A palatal cavity was prepared in rat maxillary molar teeth. Either MTA or CH was placed on the exposed pulp and all cavities were restored with composite. Rats were sacrificed for histological evaluation after 12 hours and at 2, 7, 14 and 21 days. In both the MTA and CH groups, reparative dentin formation was clearly observed on histology after 14 days. The MTA-capped pulps were found to be mostly free from inflammation, and hard tissue of a tubular consistent barrier was observed. In contrast, in CH-capped teeth, excessive formation of reparative dentin toward residual pulp was evident. The pulpal cell response beneath the reparative dentin layer was examined by immunofluorescence using antibodies against DSP. After 2 days, a few DSP immunopositive cells, most of which showed a cuboidal shape, appeared beneath the predentin layer. At 7 days, DSP-immunopositive cells with columnar odontoblast-like cells were seen beneath the newly formed hard tissues. At 14 and 21 days, DSP was more abundant in the vicinity of the odontoblastic process along the dentinal tubules than in the mineralized reparative dentin. The CH group showed strong expression patterns in terms of DSP immunoreactivity. Our results thus indicate that MTA may be a more effective pulp capping material as it induces the differentiation of odontoblast-like cells and the formation of reparative dentin without the loss of residual pulp functions.

Keyword

reparative dentin; MTA; CH; DSP

MeSH Terms

Aluminum Compounds
Animals
Antibodies
Calcium
Calcium Compounds
Calcium Hydroxide
Dental Pulp Capping
Dentin
Drug Combinations
Fluorescent Antibody Technique
Glutamates
Guanine
Hydroxides
Inflammation
Molar
Odontoblasts
Oxides
Pemetrexed
Rats
Silicates
Tooth
Aluminum Compounds
Antibodies
Calcium
Calcium Compounds
Calcium Hydroxide
Drug Combinations
Glutamates
Guanine
Hydroxides
Oxides
Silicates