Histological analyses of orthodontic force in Cavia porcellus: Comparison between immunohistochemistry and hematoxylin-eosin.

Abstract

Context: Histological quantification of osteoclasts and osteoblasts can evaluate biological responses to orthodontic tooth movement. Histological analysis of bone samples can be technically challenging. Aims: To evaluate the differences between hematoxylin and eosin (HE) staining and immunohistochemistry (IHC) in quantifying osteoblast and osteoclast cells following the application of static orthodontic force. Methods: Orthodontic force was applied using a rubber separator around the maxilla incisor of Cavia porcellus. Tooth samples were taken at 0, 4, 8, 14, 21, and 28 days after applying orthodontic force. HE and IHC staining quantify osteoblast and osteoclast cells in the alveolar bone. IHC staining, i.e., Tartrate-resistant acid phosphatase (TRAP) staining, was used to identify osteoclasts, and osteocalcin (OCN) staining was used to identify osteoblasts. Results: Significantly higher numbers of osteoclasts and osteoblasts were observed with IHC compared to HE staining (p<0.05). Significant positive linear correlations in the numbers of osteoclasts (r = 0.757) and osteoblasts (r = 0.622) identified were observed between IHC and HE staining. Conclusions: The results of this study indicate HE staining may represent an acceptable alternative method of quantifying osteoclasts and osteoblasts in the preliminary research of orthodontic tooth movement (OTM).

Keywords

• hematoxylin
• immunohistochemistry
• orthodontic
• osteocalcin
• tartrate-resistant acid phosphatase