Sudha Gudhimella1, Abdelhamed Y Ibrahim2, Divakar Karanth3, Alex M Kluemper2, Philip M Westgate4, David A Puleo5, Sarandeep S Huja6. 1. Department of Orthodontics, University of Louisville, Louisville, Ky. 2. University of Kentucky, Lexington, Ky. 3. Division of Orthodontics, University of Kentucky, Lexington, Ky. 4. Department of Biostatistics, University of Kentucky, Lexington, Ky. 5. School of Engineering, The University of Mississippi, University, Miss. 6. Department of Orthodontics, Medical University of South Carolina, Charleston, SC. Electronic address: huja@musc.edu.
Abstract
INTRODUCTION: Nonhuman animal models have been used extensively to study orthodontic tooth movement (OTM). However, rodent models have disadvantages, including a reported reduction in bone volume during OTM. The purpose of this study was to determine the viability of a skeletal anchorage and the effect of low force (∼3 cN) on interradicular bone volume during OTM. METHODS: Ninety Sprague-Dawley rats were divided into 5 time points. A miniscrew and a nickel titanium coil spring placed a load of 3 cN (experimental) or 0 cN (sham) on the maxillary first molar in a split-mouth design. Displacement of the first molar and bone volume/total volume (BV/TV) in the interradicular region were quantified. RESULTS: The success rate of the miniscrew was 98.9% (89 out of 90). Linear and angular tooth movement increased steadily (mean 0.1 mm/wk, 0.48 mm at 40 days). BV/TV was significantly reduced between the tooth movement and non-tooth movement sides in the 3 cN group: by 13%, 23%, 15%, 23%, and 16% at 3, 7, 14, 28, and 40 days, respectively. CONCLUSIONS: Our model resulted in efficient OTM without skeletal anchorage failure. BV/TV reduction was lower than in previous reports. This novel validated model is likely to be the basis for future studies.
INTRODUCTION: Nonhuman animal models have been used extensively to study orthodontic tooth movement (OTM). However, rodent models have disadvantages, including a reported reduction in bone volume during OTM. The purpose of this study was to determine the viability of a skeletal anchorage and the effect of low force (∼3 cN) on interradicular bone volume during OTM. METHODS: Ninety Sprague-Dawley rats were divided into 5 time points. A miniscrew and a nickel titanium coil spring placed a load of 3 cN (experimental) or 0 cN (sham) on the maxillary first molar in a split-mouth design. Displacement of the first molar and bone volume/total volume (BV/TV) in the interradicular region were quantified. RESULTS: The success rate of the miniscrew was 98.9% (89 out of 90). Linear and angular tooth movement increased steadily (mean 0.1 mm/wk, 0.48 mm at 40 days). BV/TV was significantly reduced between the tooth movement and non-tooth movement sides in the 3 cN group: by 13%, 23%, 15%, 23%, and 16% at 3, 7, 14, 28, and 40 days, respectively. CONCLUSIONS: Our model resulted in efficient OTM without skeletal anchorage failure. BV/TV reduction was lower than in previous reports. This novel validated model is likely to be the basis for future studies.
Authors: Maria Cadenas de Llano-Pérula; Chen Zong; Jeroen Van Dessel; Anne Marie Kuijpers-Jagtman; Guy Willems Journal: Clin Oral Investig Date: 2022-01-07 Impact factor: 3.573