Tensile Mechanical Properties of Swine Cortical Mandibular Bone

Abstract

Temporary orthodontic mini implants serve as anchorage devices in orthodontic treatments. Often, they are inserted in the jaw bones, between the roots of the teeth. The stability of the mini implants within the bone is one of the major factors affecting their success and, consequently, that of the orthodontic treatment. Bone mechanical properties are important for implant stability. The aim of this study was to determine the tensile properties of the alveolar and basal mandible bones in a swine model. The diametral compression test was employed to study the properties in two orthogonal directions: mesio-distal and occluso-gingival. Small cylindrical cortical bone specimens (2.6 mm diameter, 1.5 mm thickness) were obtained from 7 mandibles using a trephine drill. The sites included different locations (anterior and posterior) and aspects (buccal and lingual) for a total of 16 specimens from each mandible. The load-displacement curves were continuously monitored while loading half of the specimens in the oclluso-gingival direction and half in the mesio-distal direction. The stiffness was calculated from the linear portion of the curve. The mesio-distal direction was 31% stiffer than the occluso-gingival direction. The basal bone was 40% stiffer than the alveolar bone. The posterior zone was 46% stiffer than the anterior zone. The lingual aspect was stiffer than the buccal aspect. Although bone specimens do not behave as brittle materials, the diametral compression test can be adequately used for determining tensile behavior when only small bone specimens can be obtained. In conclusion, to obtain maximal orthodontic mini implant stability, the force components on the implants should be oriented mostly in the mesio-distal direction.

Extracellular matrix mineralization in the mouse osteoblast-like cell line MC3T3-E1 is regulated by actin cytoskeleton reorganization and non-protein molecules secreted from the cells themselves

“…Bone remodeling occurs via osteoblast-mediated bone formation and osteoclast-mediated bone resorption. Resorption of jaw bone tissue in edentulous patients [8,9] indicates that mechanical stimulus plays an important role in maintaining proper bone shape and structure. In this case, bone resorption proceeds at a relatively moderate pace, whereas extreme bone resorption and sclerosis are observed at injured or inflamed sites [7].…”

“…Disruption of this balance leads to metabolic bone diseases, including osteoporosis [5,6]. The resorption/production balance plays a role in local changes in bone shape such as sclerosis at sites of inflammation [7] and resorption of mandibular bone in edentulous patients [8,9]. Growth and injury are known to be the factors causing structural changes of bone.…”

ATR-FTIR Assessment of the Biochemical Composition and Micro Hardness of the Hard Tissues of Oral Cavity Submitted to Gamma Irradiation

“…Considering important to find preventive strategies in order to ensure and improve survival characteristics in the irradiated tissues and that these studies are impracticable to perform in vivo, because the ethical point of view, it must develop an in vitro protocol [14,15,[23][24][25][26][27].…”

“…The determination of effects caused by ionizing radiation, using dose for patients with head and neck cancer, in terms of variations in biochemical composition and surface microhardness [22][23][24][25][26][27][28][29][30][31], as a first step as pathophysiology comprehension, will be helpful for reduced or to eliminate inherent radiotherapy complications. Moreover, it could focus on more details from specific issues as dose reduced fractionation protocols and modalities, as long as data obtained from in vitro studies [31][32][33][34][35][36][37][38][39][40].…”

In Vitro Assessment of the Composition and Microhardness of the Hard Tissues of Oral Cavity Submitted To Gamma Irradiation

“…Considering important to find preventive strategies in order to ensure and improve survival characteristics in the irradiated tissues and that these studies are impracticable to perform in vivo, because the ethical point of view, it must develop an in vitro protocol [14,15,[23][24][25][26][27]. The determination of effects caused by ionizing radiation, using dose for patients with head and neck cancer, in terms of variations in biochemical composition and surface microhardness, as a first step as pathophysiology comprehension, will be helpful for reduced or to eliminate inherent radiotherapy complications [22][23][24][25][26][27][28][29][30][31]. Moreover, it could focus on more details from specific issues as dose reduced fractionation protocols and modalities, as long as data obtained from in vitro studies [31][32][33][34][35][36][37][38][39][40].…”