Tiancheng Li1, Zeyuan Zhou2, Han Wang1, Chunxiao Lv1, Cheng Zhang1, Guiyu Tao1, Xiaobing Li3, Shujuan Zou4, Peipei Duan5. 1. State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China School and Hospital of Stomatology, Sichuan University, Chengdu, China. 2. Department of Orthodontics, West China Dental Hospital of Chongqing, Chongqing, China. 3. State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Pediatric Dentistry, West China School and Hospital of Stomatology, Sichuan University, Chengdu, China. 4. State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China School and Hospital of Stomatology, Sichuan University, Chengdu, China. Electronic address: shujuanzou@aliyun.com. 5. State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China School and Hospital of Stomatology, Sichuan University, Chengdu, China. Electronic address: psdarling@163.com.
Abstract
INTRODUCTION: This study aimed to investigate the effects of estrogen on root repair after orthodontically induced root resorption. METHODS: Seventy-two 6-week-old female Wistar rats were randomly divided into 3 groups: ovariectomy only (OVX), ovariectomy plus estradiol injection (OVX + E2), and sham operation (control). E2 was administrated to all the experimental animals after the establishment of the root repair model. One-way analysis of variance with the Tukey post-hoc test was used to analyze the experimental results. RESULTS: Micro-computed tomography and hematoxylin and eosin staining showed that the total volumes of resorption lacunae were significantly smaller in the control and OVX + E2 groups than those in the OVX group. Alkaline phosphatase and tartrate-resistant acid phosphatase stainings suggested that the cementoblastic activities and the amount of new cementum formation were inhibited while the activities of osteoclasts were obvious in the OVX group. The immunohistochemistry stainings revealed that the osteoprotegerin to receptor activator of nuclear factor-кB ligand ratio and the phosphorylated extracellular signal-regulated kinases to extracellular signal-regulated kinases ratio of the control and OVX + E2 groups were significantly greater than those of the OVX group. CONCLUSIONS: These findings demonstrated that estrogen administration might be a solution to reduce orthodontically induced root resorption through the activation of extracellular signal-regulated kinase-1/2 pathway and enhancement of cementogenesis.
INTRODUCTION: This study aimed to investigate the effects of estrogen on root repair after orthodontically induced root resorption. METHODS: Seventy-two 6-week-old female Wistar rats were randomly divided into 3 groups: ovariectomy only (OVX), ovariectomy plus estradiol injection (OVX + E2), and sham operation (control). E2 was administrated to all the experimental animals after the establishment of the root repair model. One-way analysis of variance with the Tukey post-hoc test was used to analyze the experimental results. RESULTS: Micro-computed tomography and hematoxylin and eosin staining showed that the total volumes of resorption lacunae were significantly smaller in the control and OVX + E2 groups than those in the OVX group. Alkaline phosphatase and tartrate-resistant acid phosphatase stainings suggested that the cementoblastic activities and the amount of new cementum formation were inhibited while the activities of osteoclasts were obvious in the OVX group. The immunohistochemistry stainings revealed that the osteoprotegerin to receptor activator of nuclear factor-кB ligand ratio and the phosphorylated extracellular signal-regulated kinases to extracellular signal-regulated kinases ratio of the control and OVX + E2 groups were significantly greater than those of the OVX group. CONCLUSIONS: These findings demonstrated that estrogen administration might be a solution to reduce orthodontically induced root resorption through the activation of extracellular signal-regulated kinase-1/2 pathway and enhancement of cementogenesis.
Authors: Stephan Christian Möhlhenrich; Kristian Kniha; Zuzanna Magnuska; Sachin Chhatwani; Benita Hermanns-Sachweh; Felix Gremse; Frank Hölzle; Gholamreza Danesh; Ali Modabber Journal: Clin Oral Investig Date: 2022-05-14 Impact factor: 3.606