Multilevel biological responses following piezocision to accelerate orthodontic tooth movement: A study in rats

Aim: The objective of the present study was to explore the alveolar bone tissue response and its dynamic at the tissue, cellular, and molecular levels following a piezocision procedure in a rat model. Methods: Sixty rats were randomly allocated to either a control group (conventional orthodontic tooth movement) (TM) or a test group (piezocision-assisted orthodontic tooth movement) (TM+PS). Tissue, cellular, and molecular analyses were performed at 7, 28, and 42 days after the procedures. Orthodontic Tooth Movement (OTM) and Bone Volume Fraction (BVF) were evaluated using Nano-computed tomography. Moreover, histological parameters such as the number of osteoclasts were assessed, and the expression of cytokines involved in the bone turnover was investigated using quantitative reverse transcriptase polymerase chain reaction analysis. Results: The OTM was 1.8 times faster in the TM+PS compared with the TM at day 42. A significant decrease in BVF was found in the TM+PS group compared with the TM group at day 7 and day 28, whereas no difference was observed at day 42. The number of osteoclasts was significantly higher in the TM+PS group compared with the TM group at day 7. No difference between the two groups was found in the number of osteoclasts involved in root resorption. RANKL and osteoprotegerin were significantly higher in the piezocision group than in the control group at day 7. Conclusions: In these conditions, the efficacy of piezocision-assisted alveolar decortication to accelerate tooth movement was demonstrated, and the underlying biological responses at the tissue, cellular and molecular levels were emphasized. (C) 2019 World Federation of Orthodontists.