Evaluation of miniscrew stability using an automatic embedding auxiliary skeletal anchorage device

ABSTRACT Objective: To clarify the in vivo effect of an automatic embedding device on miniscrew stability. Materials and Methods: 42 miniscrews were implanted into rabbit femurs. The miniscrews with the novel auxiliary device formed the auxiliary group (n = 11 at 4 weeks; n = 11 at 8 weeks) and the miniscrews without the auxiliary device formed the nonauxiliary control group (n = 9 at 4 weeks; n = 11 at 8 weeks). Cortical bone thickness, distance from the cortical bone surface to the miniscrew head, and implantation depth of the spike were measured using micro-computed tomography. The mechanical retention force was evaluated by measuring the displacement of the miniscrew head after it was loaded perpendicular to its long axis. In the lateral displacement test, effects of the auxiliary (with vs without auxiliary), and time (4 vs 8 weeks) were assessed using the Brunner–Langer nonparametric analysis of longitudinal data in factorial experiments. Results: The mean implantation depth of the spike in the auxiliary group at 4 and 8 weeks was 0.28 mm (median: 0.33; SD: 0.12) and 0.37 mm (median: 0.33; SD: 0.19), respectively. The retention force was approximately 2.0 to 2.8 and 1.6 to 1.8 times greater in the auxiliary group than in the nonauxiliary group at 4 and 8 weeks, respectively. Conclusions: The auxiliary device improved the mechanical retention force without the need to increase miniscrew length or diameter. This may enable the safe use of miniscrews in difficult areas.

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In vivo quantification of age-related changes in human cortical bone thickness and porosity by HR-pQCT

Bone ◽

10.1016/j.bone.2009.01.049 ◽

2009 ◽

Vol 44 ◽

pp. S22

Author(s):

K.K. Nishiyama ◽

H.M. Macdonald ◽

H.R. Buie ◽

D.A. Hanley ◽

S.K. Boyd

Keyword(s):

Cortical Bone ◽

Bone Thickness ◽

Cortical Bone Thickness ◽

Human Cortical Bone ◽

Age Related ◽

Age Related Changes

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Trabecular and cortical bone are unaltered in response to chronic lipopolysaccharide exposure via osmotic pumps in male and female CD-1 mice

PLoS ONE ◽

10.1371/journal.pone.0243933 ◽

2021 ◽

Vol 16 (2) ◽

pp. e0243933

Author(s):

Kirsten N. Bott ◽

Jenalyn L. Yumol ◽

Elena M. Comelli ◽

Panagiota Klentrou ◽

Sandra J. Peters ◽

...

Keyword(s):

Cortical Bone ◽

Bone Structure ◽

Low Grade ◽

Micro Computed Tomography ◽

Mineral Density ◽

Potent Inducer ◽

Male And Female ◽

Osmotic Pumps ◽

Longitudinal Response

Chronic low-grade inflammation has been identified as an underlying cause of many diseases including osteoporosis. Lipopolysaccharide (LPS) is a potent inducer of the inflammatory response that can negatively affect bone outcomes by upregulating bone resorption and inhibiting bone formation. The objective of this study was to assess the longitudinal response of trabecular and cortical bone structure and bone mineral density to LPS continuously administered for 12 weeks in male and female CD-1 mice. Mice were assigned to one of four LPS groups at 8-weeks of age: placebo (0.0 μg/d), low (0.9 μg/d), mid (3.6 μg/d) and high (14.4 μg/d) dose. Trabecular and cortical bone outcomes were measured at 8, 12, 16, and 20 weeks of age using in vivo micro-computed tomography. The anticipated serum LPS dose-dependent response was not observed. Therefore, the low, mid, and high LPS groups were combined for analysis. Compared to the placebo group, endpoint serum LPS was elevated in both males (p < 0.05) and females (p < 0.05) when all LPS treatment groups were combined. However, there was no significant change in trabecular or cortical bone outcomes in the combined LPS groups compared to the placebo following the 12-week LPS intervention for either sex. This suggests that although serum LPS was elevated following the 12-week LPS intervention, the dosages administered using the osmotic pumps was not sufficient to negatively impact trabecular or cortical bone outcomes in either male or female CD-1 mice.

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Effects of a newly designed apparatus on orthodontic skeletal anchorage

European Journal of Dentistry ◽

10.4103/1305-7456.119082 ◽

2013 ◽

Vol 07 (S 01) ◽

pp. S083-S088 ◽

Cited By ~ 1

Author(s):

Murat Tozlu ◽

Didem Nalbantgil ◽

Fulya Ozdemir

Keyword(s):

Cortical Bone ◽

Lateral Displacement ◽

Tangential Force ◽

Testing Machine ◽

In Vitro Study ◽

Vitro Study ◽

Favorable Effect ◽

Control Group ◽

Insertion Torque

ABSTRACT Objective: An appliance was designed to increase the cortical bone surface contact area of miniscrew implants (MSIs). The purpose of this in vitro study was to evaluate the effects of this appliance on the anchorage force resistance and the stability of orthodontic MSIs. Materials and Methods: A total of 48 MSIs were placed into bone specimens prepared from the ilium of bovines. Half were placed with the newly designed apparatus and half were placed conventionally. All the specimens were subjected to tangential force loading perpendicular to the MSI with lateral displacement of 0.6 mm, using an Instron Universal Testing machine. The maximum removal torque of each tested specimen was also recorded. Both study and control groups were divided into two subgroups based on whether they had thin and thick cortical bone. Results: The test group had statistically higher force anchorage resistance and maximum insertion torque values than the control group (p < 0.001). The results were found to be more significant in cases in which the cortical bone was thin (p < 0.001). Conclusions: Within the limits of this in vitro study, the present findings suggest that the newly designed apparatus might have a favorable effect on MSI stability in patients presenting with thin cortical bone. Clinical studies are necessary to confirm the results that were observed in vitro.

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Bone mineral response to ammonium sulphate offered as a lick supplement in beef calves

Journal of the South African Veterinary Association ◽

10.4102/jsava.v77i1.334 ◽

2006 ◽

Vol 77 (1) ◽

Cited By ~ 1

Author(s):

L.E. Motsei ◽

D.E. Beighle

Keyword(s):

Cortical Bone ◽

Ammonium Sulphate ◽

Experimental Period ◽

Control Group ◽

Bone Thickness ◽

Bone Meal ◽

Beef Calves ◽

P Concentration ◽

P Content ◽

Ca:P Ratio

Sixteen Bonsmara calves (4 males, 12 females) between 10 and 18 months of age were blocked according to age and sex and randomly assigned to 2 groups. They were offered licks containing bone meal and salt (50:50 ratio) (control) and bone meal and ammonium sulphate (NH4SO4) at 1.25, 2.5, 5, 10, 15, and 18 % (treatment) to evaluate the effects of dietary anions on bone phosphate (P) concentration. Bone P concentration was significantly (P<0.05) higher in the NH4SO4 group compared with the control group, indicating that NH4SO4 was able to increase the P content of bone at each of the 6 concentrations used in the lick relative to the control animals, thereby improving the P status of the animals. Ammonium sulphate at 15% and 18% in the lick also significantly (P <0.05) increased bone P compared with the lower concentrations of NH4SO4. Bone calcium (Ca) fluctuated as a result of the acidogenic lick. There was absorption of Ca when P was being resorbed and resorption of Ca when P was being absorbed into and out of bone. Bone Ca:P ratio ranged from 3.2 to 6.4 among the control group and 1.6 to 4.3 among the treatment group. Animals receiving the acidogenic lick had a higher percentage ash compared to the control group for most of the experimental period. Bone magnesium (Mg) fluctuated in response to the acidogenic lick, and it was difficult to show a relationship between bone Mg and Ca or P. The overall mean cortical bone thickness was significantly (P < 0.05) greater in treatment (1.60 mm) compared with control (1.43 mm) calves and this was also true at sampling periods 2, 4, 5 and 6. Bone thickness followed bone P and not bone Ca. Results from this research indicate that the addition of ammonium sulphate to a lick had a beneficial effect in improving the P status by increasing bone P and improving the mineral status of bone by increasing the thickness of cortical bone and percentage ash.

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Characterization of the novel OXA-213-like β-lactamase OXA-822 from Acinetobacter calcoaceticus

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/dkaa488 ◽

2020 ◽

Author(s):

Manuela Tietgen ◽

Laura Leukert ◽

Julian Sommer ◽

Jan S Kramer ◽

Steffen Brunst ◽

...

Keyword(s):

Galleria Mellonella ◽

Sequence Similarity ◽

Acinetobacter Calcoaceticus ◽

Amino Acid Sequence Similarity ◽

Control Group ◽

Infection Model ◽

The Novel ◽

High Turnover

Abstract Objectives This study analysed the novel carbapenem-hydrolysing class D β-lactamase OXA-822 identified in the clinical Acinetobacter calcoaceticus isolate AC_2117. Methods WGS was employed for identification of β-lactamases. Micro-broth dilution was used for evaluation of antibiotic susceptibility of AC_2117 and transformants containing blaOXA-822. After heterologous purification of OXA-822, OXA-359 and OXA-213, enzyme kinetics were determined using spectrometry. The effect of OXA-822 upon meropenem treatment was analysed in the Galleria mellonella in vivo infection model. Results OXA-822 is a member of the intrinsic OXA-213-like family found in A. calcoaceticus and Acinetobacter pittii. Amino acid sequence similarity to the nearest related OXA-359 was 97%. Production of OXA-822, OXA-359 and OXA-213 in Acinetobacter baumannii ATCC® 19606T resulted in elevated MICs for carbapenems (up to 16-fold). Penicillinase activity of the purified OXA-822 revealed high KM values, in the millimolar range, combined with high turnover numbers. OXA-822 showed the highest affinity to carbapenems, but affinity to imipenem was ∼10-fold lower compared with other carbapenems. Molecular modelling revealed that imipenem does not interact with a negatively charged side chain of OXA-822, as doripenem does, leading to the lower affinity. Presence of OXA-822 decreased survival of infected Galleria mellonella larvae after treatment with meropenem. Only 52.7% ± 7.7% of the larvae survived after 24 h compared with 90.9% ± 3.7% survival in the control group. Conclusions The novel OXA-822 from a clinical A. calcoaceticus isolate displayed penicillinase and carbapenemase activity in vitro, elevated MICs in different species and decreased carbapenem susceptibility in A. baumannii in vivo.

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Novel nanotech antioxidant cocktail prevents medical diagnostic procedures ionizing radiation effects

Scientific Reports ◽

10.1038/s41598-021-84596-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Miguel Gorenberg ◽

Abed Agbarya ◽

David Groshar ◽

Ilya Volovik ◽

Ofir Avitan ◽

...

Keyword(s):

Ionizing Radiation ◽

Protective Effect ◽

Radiation Effects ◽

Diagnostic Procedures ◽

Peripheral Blood Lymphocytes ◽

Dna Lesions ◽

Control Group ◽

The Novel ◽

Significant Difference

AbstractIonizing radiation (IR) exposure results in oxidative damage causing cytotoxic and genotoxic effects. Double-strand breaks (DSBs) are considered the most significant DNA lesions induced by ionizing radiation. The present study evaluates the radio protective effect of a novel antioxidant cocktail through quantification of DSB in peripheral blood lymphocytes (PBL) in vivo. The study included 16 consecutive patients who were divided into 2 groups, 6 patients received the novel antioxidant cocktail and 10 control patients. Blood samples were drawn from the patients undergoing bone scan, before the injection of the 99mTc MDP tracer and 2 h after the injection. Quantification of the IR damage was done by Immunofluorescence analysis of the phosphorylated histone, γ-H2AX, used to monitor DSB induction and repair in PBL. The radiation effect of the control group was measured by 2 variables, the average DBSs foci per nucleus and the percent of the DSB bearing cells in PBL. The findings showed a significant increase in the DSBs after isotope injection with an average increment of 0.29 ± 0.13 of foci/nucleus and 17.07% ± 7.68 more DSB bearing cells (p < 0.05). The cocktail treated group showed a lower difference average of − 2.79% ± 6.13 DSB bearing cells. A paired t-test revealed a significant difference between the groups (p < 0.005) confirming the cocktail’s protective effect. The novel anti-oxidant treatment decreases the oxidative stress-induced DNA damage and can be considered as a preventative treatment before radiation exposure.

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Evaluation of Bone Sialoprotein Coating of Three-Dimensional Printed Calcium Phosphate Scaffolds in a Calvarial Defect Model in Mice

Materials ◽

10.3390/ma11112336 ◽

2018 ◽

Vol 11 (11) ◽

pp. 2336 ◽

Cited By ~ 3

Author(s):

Andreas Baranowski ◽

Anja Klein ◽

Ulrike Ritz ◽

Hermann Götz ◽

Stefan Mattyasovszky ◽

...

Keyword(s):

Calcium Phosphate ◽

Bone Formation ◽

Three Dimensional ◽

Bone Substitutes ◽

Bone Sialoprotein ◽

Control Group ◽

Calvarial Defect ◽

Micro Computed Tomography ◽

Bone Thickness ◽

Local Bone

The bioactive coating of calcium phosphate cement (CPC) is a promising approach to enhance the bone-healing properties of bone substitutes. The purpose of this study was to evaluate whether coating CPCs with bone sialoprotein (BSP) results in increased bone formation. Forty-five female C57BL/6NRj mice with an average age of six weeks were divided into three groups. Either a BSP-coated or an uncoated three-dimensional plotted scaffold was implanted into a drilled 2.7-mm diameter calvarial defect, or the defect was left empty (control group; no CPC). Histological analyses revealed that BSP-coated scaffolds were better integrated into the local bone stock eight weeks after implantation. Bone volume/total volume (BV/TV) ratios and bone thickness at the bone–implant contact were analyzed via micro computed tomography (µCT) after eight weeks. BSP-coated scaffolds and uncoated CPC scaffolds increased bone thickness in comparison to the control (CPC + BSP: 691.1 ± 253.5 µm, CPC: 603.1 ± 164.4 µm, no CPC: 261.7 ± 37.8 µm, p < 0.01). Accordingly, BV/TV was enhanced in both scaffold groups (CPC + BSP: 1.3 ± 0.5%, CPC: 0.9 ± 0.5%, no CPC: 0.2 ± 0.3%, p < 0.01). The BSP coating showed a tendency towards an increased bone thickness (p = 0.18) and BV/TV (p = 0.18) in comparison to uncoated CPC scaffolds. However, a significant increase in bone formation through BSP coating was not found.

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Influence of estrogen deficiency and tibolone therapy on trabecular and cortical bone evaluated by computed radiography system in rats

Acta Cirurgica Brasileira ◽

10.1590/s0102-86502012000300003 ◽

2012 ◽

Vol 27 (3) ◽

pp. 217-222

Author(s):

Ana Carolina Bergmann de Carvalho ◽

Gustavo Vieira Oliveira Fernandes ◽

Inayá Lima ◽

Davi Ferreira de Oliveira ◽

Helene Nara Henriques ◽

...

Keyword(s):

Femoral Head ◽

Cortical Bone ◽

Optical Density ◽

Computed Radiography ◽

Female Rats ◽

Control Group ◽

Bone Thickness ◽

Long Period ◽

Radiography System ◽

High Doses

PURPOSE: To verify the effects of tibolone administration on trabecular and cortical bone of ovariectomized female rats by computed radiography system (CRS). METHODS: The experiment was performed on two groups of rats previously ovariectomized, one received tibolone (OVX+T) while the other did not (OVX), those groups were compared to a control group (C) not ovariectomized. Tibolone administration (1mg/day) began thirty days after the ovariectomy and the treatment remained for five months. At last, the animals were euthanized and femurs and tibias collected. Computed radiographies of the bones were obtained and the digital images were used to determine the bone optical density and cortical thickness on every group. All results were statistically evaluated with significance set at P<0.05%. RESULTS: Tibolone administration was shown to be beneficial only in the densitometric analysis of the femoral head, performing higher optical density compared to OVX. No difference was found in cortical bone thickness. CONCLUSION: Ovariectomy caused bone loss in the analyzed regions and tibolone administered in high doses over a long period showed not to be fully beneficial, but preserved bone mass in the femoral head.

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Evaluation of in Vivo Response of Three Biphasic Scaffolds for Osteochondral Tissue Regeneration in a Sheep Model

Veterinary Sciences ◽

10.3390/vetsci6040090 ◽

2019 ◽

Vol 6 (4) ◽

pp. 90 ◽

Cited By ~ 1

Author(s):

Alberto M. Crovace ◽

Alessia Di Giancamillo ◽

Francesca Gervaso ◽

Laura Mangiavini ◽

Davide Zani ◽

...

Keyword(s):

Tissue Regeneration ◽

Collagen Matrix ◽

Control Group ◽

The Novel ◽

Sheep Model ◽

Complete Restoration ◽

Different Types ◽

Ct Analysis ◽

Reparative Process

Osteochondral defects are a common problem in both human medicine and veterinary practice although with important limits concerning the cartilaginous tissue regeneration. Interest in the subchondral bone has grown, as it is now considered a key element in the osteochondral defect healing. The aim of this work was to generate and to evaluate the architecture of three cell-free scaffolds made of collagen, magnesium/hydroxyapatite and collagen hydroxyapatite/wollastonite to be implanted in a sheep animal model. Scaffolds were designed in a bilayer configuration and a novel “Honey” configuration, where columns of hydroxyapatite were inserted within the collagen matrix. The use of different types of scaffolds allowed us to identify the best scaffold in terms of integration and tissue regeneration. The animals included were divided into four groups: three were treated using different types of scaffold while one was left untreated and represented the control group. Evaluations were made at 3 months through CT analysis. The novel “Honey” configuration of the scaffold with hydroxyapatite seems to allow for a better reparative process, although we are still far from obtaining a complete restoration of the defect at this time point of follow-up.

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Short-term effects of nicotine on orthodontically induced root resorption in rats

The Angle Orthodontist ◽

10.2319/101014-727.1 ◽

2015 ◽

Vol 86 (2) ◽

pp. 199-205 ◽

Cited By ~ 4

Author(s):

Jing Li ◽

Xuxia Wang ◽

Na Li ◽

Dehua Zhenga ◽

Yuran Su ◽

...

Keyword(s):

Rat Model ◽

Tooth Movement ◽

Root Resorption ◽

Treated Group ◽

Control Group ◽

Nicotine Exposure ◽

Rankl Expression ◽

Micro Computed Tomography ◽

Control Groups

ABSTRACT Objective: To investigate the effect of nicotine exposure on root resorption in an in vivo rat model of orthodontic tooth movement (OTM), and its association with odontoclastogenesis and receptor activator of nuclear factor-kappa B ligand (RANKL) expression. Materials and Methods: Forty-eight 10-week-old male Wistar rats were divided into three groups. The negative control group was untreated. The left maxillary first molars in the nicotine-treated group and the positive control group received OTM with an initial force of 0.6 N in the mesial direction. Also, the nicotine-treated group received intraperitoneal injection of nicotine at 7 mg/kg per day. After 21 days, the rats were humanely killed. Eight rats from each group were randomly chosen for crater volume analysis by micro-computed tomography. For the remaining eight rats in each group, specimen slices were generated for histologic examination to determine the odontoclast number and the mean optical density value of RANKL. Results: The resorption volumes in the nicotine-treated group were significantly larger than those in the control groups. Also, the nicotine-treated group displayed significantly higher number of odontoclasts and elevated RANKL expression compared to the control groups. Conclusions: In an in vivo rat model, nicotine exposure promotes odontoclastogenesis and RANKL expression, evoking aggravated root resorption during OTM.

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