Changes in cortical bone mineralization in the mouse mandible with regenerated condyle

Abstract

The objective of this study was to evaluate the effects of condylectomy and of a functional appliance on the mineral content, density, and area of the mandibular cortical bone in a growing mouse model. In the condylectomy group, a unilateral condylectomy was performed on the right side of the mouse mandible. In the condylectomy + appliance group, a functional appliance was used to reposition the mandible after the unilateral condylectomy. All mice were killed 4 wk after surgery. Each mandible was then subjected to analyses of cortical bone mineral content (CRT_CNT), cortical bone density (CRT_DEN), and cortical bone area (CRT_A) by peripheral quantitative computed tomography (pQCT). The CRT_CNT, CRT_DEN, and CRT_A values were significantly lower in the condylectomized mandible (right side) than in the non-condylectomized mandible (left side). However, in the condylectomized animals in which a functional appliance was used, the CRT_CNT, CRT_DEN, and CRT_A values became higher than those in the mice treated with condylectomy alone. No significant differences were found in the CRT_CNT, CRT_DEN, and CRT_A between non-condylectomized (left side) mandibles, mandibles treated with condylectomy + functional appliance (right side), and control mandibles. It was thus shown that a functional appliance used to reposition the condylectomized mandible forward in a symmetric position induced improvement of the cortical bone in a mouse model in terms of cortical bone mineral content, density, and area.

Early Treatment of Unilateral Condylar Hyperplasia in Adolescents: Preliminary Results

“…Between 10 and 16 years old, almost 70% of the mineralization of the cortical bone of the mandible is complete [18]. An uncontrolled disease in the mandibular condyle under 16 years old can cause alterations in the growth and development of the mandible [19]. Genetic conditions associated with UCH as well as phenotypes play a role in this scenario [20].…”

Evaluation of Regenerative Processes in a Rat Model of Mandibular Condyle Defect using in vivo Micro X-Ray Computed Tomography

“…Bone lengthening was used in several of the studies in which the mandibular head was transected 4,5) . Models in which only the mandibular head was removed have been widely studied radiologically using soft X-rays and histological observations, and several studies have measured the mineral quantity of the cortical bone 6) . However, many studies have examined alterations in occlusion caused by transection of the mandibular head [6][7][8] ,the direction and position of the regenerated mandibular head 7,8) ,or the thickness of the temporomandibular 410…”

Is there New Condylar Formation after Unilateral Partial Mandibular Condylectomy?

“…Miyamoto et al (1999) desarrollaron una investigación en ovejas, desarrollando condilectomía unilaterales exclusivas; demostraron que los cóndilos se pueden regenerar y adoptar una forma semejante a cóndilos normales después de 3 meses tanto en la visión microscópica y macroscópica, respetando las capas articulares presentes; sin embargo, no se realiza una descripción de las características de ellas. Fujita et al (2011) en un estudio en ratas, indicó que la mineralización de los sectores con condilectomía fueron bajas al ser comparados con los cóndilos de control y que elementos aplicados para inducir a la simetría mandibular resultaron en mayor corticalización del cóndilo. Dimitroulis et al (2011), realizó una análisis de la respuesta tisular a la condilectomía, disectomía e instalación de injerto dérmico-adiposo en el sitio articular en conejos.…”