Failure strength of human vertebrae: Prediction using bone mineral density measured by DXA and bone volume by micro-CT

ABSTRACT Aggregatibacter actinomycetemcomitans is a Gram-negative commensal bacterium of the oral cavity which has been associated with the pathogenesis of periodontitis with severe alveolar bone destruction. The role of host factors such as reactive oxygen and nitrogen intermediates in periodontal A. actinomycetemcomitans infection and progression to periodontitis is still ill-defined. Therefore, this study aimed to analyze the role of NADPH oxidase and inducible nitric oxide synthase (iNOS) in a murine model of A. actinomycetemcomitans-induced periodontitis. NADPH oxidase-deficient (gp91phox knockout [KO]), iNOS-deficient (iNOS KO), and C57BL/6 wild-type mice were orally infected with A. actinomycetemcomitans and analyzed for bacterial colonization at various time points. Alveolar bone mineral density and alveolar bone volume were quantified by three-dimensional micro-computed tomography, and the degree of tissue inflammation was calculated by histological analyses. At 5 weeks after infection, A. actinomycetemcomitans persisted at significantly higher levels in the murine oral cavities of infected gp91phox KO mice than in those of iNOS KO and C57BL/6 mice. Concomitantly, alveolar bone mineral density was significantly lower in all three infected groups than in uninfected controls, but with the highest loss of bone density in infected gp91phox KO mice. Only infected gp91phox KO mice revealed significant loss of alveolar bone volume and enhanced inflammatory cell infiltration, as well as an increased number of osteoclasts. Our results indicate that NADPH oxidase is important to control A. actinomycetemcomitans infection in the murine oral cavity and to prevent subsequent alveolar bone destruction and osteoclastogenesis.

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Newly Formed Bone around Implanted New Titanium Alloy: Ti-15%Zr-4%Nb-4%Ta

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.361-363.661 ◽

2007 ◽

Vol 361-363 ◽

pp. 661-664

Author(s):

Hiroshi Nakada ◽

Yasuko Numata ◽

Taketoshi Suwa ◽

Y. Okazaki ◽

Racquel Z. LeGeros ◽

...

Keyword(s):

Mechanical Properties ◽

Bone Mineral Density ◽

Titanium Alloy ◽

Surface Treatment ◽

Bone Mineral ◽

Ti Alloy ◽

Micro Ct ◽

Mineral Density ◽

Biological Safety ◽

Biological Performance

We have developed a new Ti alloy, Ti-15%Zr-4%Nb-4%Ta alloy (Ti-15-4-4) that showed higher biological safety and mechanical properties than the currently used Ti-6%Al-4%V alloy. The purpose of this study is to determine the biological performance of the new alloy. Ti-15-4-4 implants (machined or blasted) were placed in surgically created defects in rabbit femurs. The rabbits were sacrificed after 4, 8, 16, 24 and 48 weeks. Bone mineral density (BMD) and area of newly formed bone around the implants were measured using micro-CT. Results showed that the Ti-15-4-4 alloy is biocompatible and forms new bone around the Ti-15-4-4 implant, regardless of the surface treatment. The BMD and area of newly formed bone around the blasted implant surfaces were significantly greater than those around the machined surfaces. These results indicate that the new Ti-15-4-4 alloy has a potential for use as implants and has the advantage of improved mechanical properties described in earlier studies.

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Effect of growth hormone on bone: Bone mineral density, trabecular bone volume, and alkaline phosphatase improve or are restored in the dwarf rat treated with growth hormone

Journal of Bone and Mineral Research ◽

10.1002/jbmr.5650100118 ◽

2009 ◽

Vol 10 (1) ◽

pp. 127-131 ◽

Cited By ~ 16

Author(s):

Nancy M. Wright ◽

Josette Renault ◽

Bruce Hollis ◽

Norman H. Bell ◽

Lyndon L. Key

Keyword(s):

Bone Mineral Density ◽

Growth Hormone ◽

Alkaline Phosphatase ◽

Trabecular Bone ◽

Bone Mineral ◽

Bone Volume ◽

Trabecular Bone Volume ◽

Mineral Density

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Fam3c modulates osteogenic cell differentiation and affects bone volume and cortical bone mineral density

BoneKEy Reports ◽

10.1038/bonekey.2016.14 ◽

2016 ◽

Vol 5 ◽

Cited By ~ 7

Author(s):

Jorma A Määttä ◽

Ameya Bendre ◽

Mervi Laanti ◽

Kalman G Büki ◽

Pia Rantakari ◽

...

Keyword(s):

Bone Mineral Density ◽

Cell Differentiation ◽

Cortical Bone ◽

Bone Mineral ◽

Bone Volume ◽

Osteogenic Cell ◽

Mineral Density ◽

Cortical Bone Mineral Density

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Trabecular bone volume and bone mineral density in the mandible.

Dentomaxillofacial Radiology ◽

10.1038/sj.dmfr.4600217 ◽

1997 ◽

Vol 26 (2) ◽

pp. 101-106 ◽

Cited By ~ 19

Author(s):

C Lindh ◽

A Petersson ◽

B Klinge ◽

M Nilsson

Keyword(s):

Bone Mineral Density ◽

Trabecular Bone ◽

Bone Mineral ◽

Bone Volume ◽

Trabecular Bone Volume ◽

Mineral Density

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Adverse effects of strenuous exercise: a densitometric and histomorphometric study in the rat

Journal of Applied Physiology ◽

10.1152/jappl.1994.76.5.1999 ◽

1994 ◽

Vol 76 (5) ◽

pp. 1999-2005 ◽

Cited By ~ 64

Author(s):

S. Bourrin ◽

C. Genty ◽

S. Palle ◽

C. Gharib ◽

C. Alexandre

Keyword(s):

Bone Mineral Density ◽

Bone Loss ◽

Bone Mineral ◽

Cancellous Bone ◽

Bone Growth ◽

Proximal Tibia ◽

Bone Volume ◽

Mineral Density ◽

Osteoblastic Activity ◽

Tibia Length

To investigate the manner in which cancellous bone in different skeletal sites and within a bone site adapts to strenuous training, 5-wk-old male rats were subjected to intensive treadmill running [80% of maximal O2 consumption (VO2max)] for 11 wk. VO2max, tibia length, and bone mineral density were measured. Histomorphometric analysis was performed in the epiphysis, primary spongiosa (1 zero sp) and secondary spongiosa (2 zero sp) of the contralateral proximal tibia, and the 2 zero sp of thoracic and lumbar vertebrae. VO2max was increased by 39%. No changes were observed in vertebrae. Tibia length, 1 zero sp bone volume, and number of trabeculae were significantly decreased, indicating a retarded longitudinal bone growth. Bone mineral density in the proximal tibia was significantly decreased. In the epiphysis, a trabecular thinning and an increase of trabecular number were shown. In the 2 zero sp, bone volume and number of trabeculae were significantly decreased. The increased total eroded surfaces could indicate an early but transient increase in bone resorption activity. Osteoid thickness was reduced, whereas osteoclast number and osteoid surfaces were unchanged, suggesting that the observed bone loss was mostly due to an impaired osteoblastic activity. In conclusion, 1) strenuous training in young rats reduces longitudinal bone growth and induces bone loss, 2) the cancellous bone adaptation is site specific, and 3) the bone loss is mainly due to decreased osteoblastic activity rather than a global adaptation of bone remodeling.

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Anabolic Effect of Estrogen Replacement on Bone in Postmenopausal Women with Osteoporosis: Histomorphometric Evidence in a Longitudinal Study1

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jcem.86.1.7161 ◽

2001 ◽

Vol 86 (1) ◽

pp. 289-295

Author(s):

Gautam Khastgir ◽

John Studd ◽

Nigel Holland ◽

Jamshid Alaghband-Zadeh ◽

Simon Fox ◽

...

Keyword(s):

Bone Mineral Density ◽

Postmenopausal Women ◽

Bone Mineral ◽

Cancellous Bone ◽

Wall Thickness ◽

Bone Volume ◽

Anabolic Effect ◽

Mineral Density ◽

Bone Biopsies ◽

Bone Gain

It is well recognized that estrogen (E2) prevents postmenopausal bone loss by suppressing bone resorption. Despite evidence that E2 may also stimulate bone formation in animals, an anabolic effect in humans is still controversial. To investigate this, we studied 22 older postmenopausal females, with a mean age of 65.4 yr and mean interval of 16.9 yr since menopause and low bone mineral density. Transcortical iliac bone biopsies were performed before and 6 yr after E2 replacement therapy (ERT) [75 mg percutaneous E2 replaced 6-monthly plus oral medroxy progesterone acetate (5 mg daily) for 10 days each calendar month]. The mean serum E2 level after 6 yr of treatment was 1077 (range, 180-2568) pmol/L. Bone mineral density improved in every patient, with a median increase of 31.4% at the lumbar spine and 15.1% at the proximal femur. Bone histomorphometry showed an increase in cancellous bone volume from 10.75% to 17.31% (P < 0.001). The wall thickness after 6 yr of E2 treatment was 38.30 μm compared with 31.20 μm before commencement of ERT (P < 0.0005), indicating net bone gain. This is the first report showing histological evidence for an increase in cancellous bone volume, together with an increase in wall thickness, in a longitudinal follow-up study of ERT in older postmenopausal women. Our results show that E2 is capable of exerting an anabolic effect in women with osteoporosis, even when started well into the menopause.

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