The formation of tertiary dentin after pulp capping with a calcium phosphate cement, loaded with PLGA microparticles containing TGF-b1

The aim of the current study was to evaluate the effect of a calcium phosphate material equipped with poly (lactic-co-glycolic acid) microspheres for pulp capping, and to measure the dentin bridge formation, when using various concentrations of transforming growth factor (TGF) b1. Preset samples were made (2 mm diameter; 2 mm height), containing 0 (controls), 20, or 400 ng TGF-b1. These were placed in goat incisors. Incisors capped with glass-ionomer cement only were used as negative controls. Twelve weeks after pulp capping, the incisors were retrieved, processed for histology, and graded on basis of tertiary dentin formation. The results showed that new dentin formation was seen in all samples, except the negative controls. The histological grading indicated significant differences between the samples loaded with high amount of TGF-b1 versus the three other groups (p < 0.05). In conclusion, our study demonstrated that the composite with 400 ng TGF-b1 was able to trigger resident stem cells in the pulp to differentiate into odontoblast-like cells and to induce the formation of tertiary dentin. The material might be a good candidate for vital pulp therapy. Production and manipulation methods could be improved for follow-up studies. 2007 Wiley Periodicals, Inc. J Biomed Mater Res 85A: 439–444, 2008