T Kustro1, T Kiss2, D Chernohorskyi1, Y Chepurnyi3, Z Helyes4, A Kopchak1. 1. Department of Stomatology, Bogomolets National Medical University, 13, T. Shevchenko blvd, 01601, Kyiv, Ukraine. 2. János Szentágothai Research Centre & Department of Pharmacology and Pharmacotherapy, Medical School, University of Pecs, Ifjúság útja 20, Pécs, H-7624, Hungary. 3. Department of Stomatology, Bogomolets National Medical University, 13, T. Shevchenko blvd, 01601, Kyiv, Ukraine. Electronic address: 80667788837@ukr.net. 4. János Szentágothai Research Centre & Department of Pharmacology and Pharmacotherapy, Medical School, University of Pecs, Ifjúság útja 20, Pécs, H-7624, Hungary; PharmInVivo Ltd., Szondi Gy. u. 7, H-7629, Pécs, Hungary.
Abstract
PURPOSE: The goal of this study was the evaluation of the bone tissue structural characteristics over the time course of mandibular defect healing using micro-CT technique, as well as determination of the inter-relationships between different micro-CT parameters used for assessment of the bone regeneration process and the patterns of their dynamic changes. MATERIALS AND METHODS: The body and ramus of the mandible was exposed in 24 Wistar rats. A 2-mm full thickness bony defect was created. Animals were randomized into four groups, which were ended 3, 6, 12 and 24 weeks after operation. The mandible was excised and underwent micro-CT analysis. For statistical evaluation, the Mann-Whitney U test, polynomial or exponential regression and Spearman analysis were applied. RESULTS: The absolute volume of the bone regenerate increased from 1.69 ± 0.53 mm3 (3 weeks) to 3.36 mm3 ± 0.56 (6 months), as well as percentage of bone volume, increased significantly from 12.5 ± 2.3% at the 3-week term to 26.4 ± 8.7% at the 3-month term or 23.1 ± 8.7% at the 6-month term. Structural (trabecular) thickness gradually increased from 0.13 ± 0.007 mm at the 3-week term to 0.3 ± 0.11 mm at the 6-month term. The structural model index was 0.79 ± 0.46 in the early phase after trauma and then decreased to negative values. CONCLUSION: The bone regeneration process was characterized by a significant increase (p < 0.05) in bone volume, percentage of bone volume, structural thickness and bone mineral density, and a decrease in bone surface-to-volume ratio and volume of pore space from the 3-week term to the 6-month term. These changes can be mathematically described by nonlinear exponential regression models.
PURPOSE: The goal of this study was the evaluation of the bone tissue structural characteristics over the time course of mandibular defect healing using micro-CT technique, as well as determination of the inter-relationships between different micro-CT parameters used for assessment of the bone regeneration process and the patterns of their dynamic changes. MATERIALS AND METHODS: The body and ramus of the mandible was exposed in 24 Wistar rats. A 2-mm full thickness bony defect was created. Animals were randomized into four groups, which were ended 3, 6, 12 and 24 weeks after operation. The mandible was excised and underwent micro-CT analysis. For statistical evaluation, the Mann-Whitney U test, polynomial or exponential regression and Spearman analysis were applied. RESULTS: The absolute volume of the bone regenerate increased from 1.69 ± 0.53 mm3 (3 weeks) to 3.36 mm3 ± 0.56 (6 months), as well as percentage of bone volume, increased significantly from 12.5 ± 2.3% at the 3-week term to 26.4 ± 8.7% at the 3-month term or 23.1 ± 8.7% at the 6-month term. Structural (trabecular) thickness gradually increased from 0.13 ± 0.007 mm at the 3-week term to 0.3 ± 0.11 mm at the 6-month term. The structural model index was 0.79 ± 0.46 in the early phase after trauma and then decreased to negative values. CONCLUSION: The bone regeneration process was characterized by a significant increase (p < 0.05) in bone volume, percentage of bone volume, structural thickness and bone mineral density, and a decrease in bone surface-to-volume ratio and volume of pore space from the 3-week term to the 6-month term. These changes can be mathematically described by nonlinear exponential regression models.
Authors: Buyanbileg Sodnom-Ish; Mi Young Eo; Ji Hye Oh; Mi Hyun Seo; Hoon Joo Yang; Jong Ho Lee; Soung Min Kim Journal: Sci Rep Date: 2021-06-03 Impact factor: 4.379