Systemic effects of oral tolerance in bone healing.

Bone fractures cause acute inflammation that, despite being important for initial repair, may delay the healing of the damaged bone. Parenteral injection of dietary protein has been shown to decrease inflammation and accelerate the repair of skin wounds and other inflammatory pathologies. Thus, our aim was to evaluate whether the intraperitoneal (i.p.) immunization with zein, an abundant protein in rodent chow, would favor bone healing. Wistar rats received i.p. immunization: saline (SG), adjuvant (AG) and zein associated with adjuvant (ZG). Then, a 2 mm of defect bone was performed on the right tibia, and on days 7, 14, 28 and 45 thereafter, analyses were performed. The results showed that the injection of zein reduced inflammation without impairing bone mineralization. Moreover, biomechanical tests demonstrated higher levels of maximum force (N) in ZG, indicating better mechanical resistance in relation to the others. The computerized tomography also indicated lower levels of medullary content in the ZG than in the SG, suggesting the absence of trabeculae in the medullary region in the ZG. These findings suggest that the injection of zein in previously tolerated animals may improve bone repair, leading to mechanically functional bone formation.

Treatment of tibial large bone defects: A comparative study of bone transport over an intramedullary nail in combination with antibiotic-impregnated calcium sulphate versus bone transport alone with antibiotic-impregnated calcium sulphate.

PURPOSE: To compare the bone transport over an intramedullary nail in combination with antibiotic-impregnated calcium sulphate versus bone transport alone with antibiotic-impregnated calcium sulphate for the treatment of tibial large bone defects. METHODS: A retrospective analysis was conducted by enroling 33 surgically treated patients with tibial large bone defects after the debridement for tibial infection or osteomyelitis who were admitted in Lower Limb Surgery Ward of Traumatic orthopaedic Department, Xi'an Honghui Hospital from January 2018 to January 2021. All the patients were categorized in Group A (transport over intramedullary nail, 12 cases) and Group B (transport alone, 21 cases) based on the surgery strategy. The collected clinical materials and data included gender, age, injury mechanism, smoking habits, comorbidity diseases, initial fracture type (open or close), bone defect size, surgical duration, intraoperative bleeding loss, resorption time of calcium sulphate, bone transport time, external fixation time, external fixation index, weight bearing time, complications and Paley bone and functional criteria. RESULTS: Thirty-three patients were enroled and successfully followed up with an average time of 15.25±4.31 months ranged from 8 to 21 months in Group A and an average time of 17.09±5.64 months ranged from 9 to 31 months in Group B. No significantly statistical differences of the demographic data were discovered between the two groups. There were no significantly statistical differences of the average bone defect size, intraoperative bleeding loss, resorption time of calcium sulphate and bone transport time between the two groups. However, the average surgical duration (P = 0.002) was significantly longer in Group A than Group B and the average external fixation time (P<0.001), external fixation index(P = 0.002) and weight bearing time (P = 0.030) were significantly shorter in Group A than Group B. No significantly statistical difference of excellent and good rate of bone outcomes and complication rate was observed, however, the excellent and good rate of functional outcomes (P = 0.041) was significantly higher in Group A than Group B. CONCLUSION: Compared with the conventional Ilizarov technique combining with antibiotic-impregnated calcium sulphate for large tibial bone defects, bone transport over an intramedullary nail in combination with antibiotic-impregnated calcium sulphate had favourable external fixation time, external fixation index, weight bearing time and clinical functional outcomes which effectively suppressed the infection and allowed patients earlier removal of the external fixator and weight bearing for rehabilitation.

A Composite Deferoxamine/Black Phosphorus Nanosheet/Gelatin Hydrogel Scaffold for Ischemic Tibial Bone Repair.

Introduction: Bone delay union is mostly caused by lack of blood supply. Although autografts, allografts and artificial bone have been widely used to treat bone delay union, the bone regeneration fails in the ischemic site accompanied by the bone donor site complications and disease transmission. Recently, there is a growing recognition of the importance of hydrogel scaffolds which are regarded as an eligible engineer tissue for bone repair. However, hydrogel is still limited in improving neovascularization. Methods: In this work, black phosphorus nanosheet and deferoxamine (BPN-DFO) were loaded in the gelatin hydrogel to overcome the high risk of bone delay union and systemically investigated the regeneration capability of BPN-DFO hydrogel in vitro and vivo. Results: The resulting BPN-DFO hydrogel scaffold showed superior swollen, degradation and release rate, as well as satisfied biocompatibility. BPN-DFO hydrogel shown the significant up-expression of mRNA related to bone regeneration and cell proliferation. In vivo, the proposed BPN-DFO hydrogel significantly improved osteogenesis and neovascularization in the ischemic tibial bone site of SD rats with acute femoral artery occlusion. Both macroscopic and histological evaluation of new regenerated bone showed newly formed blood vessel and collagen using BPN-DFO hydrogel. The immunohistochemistry and RT-PCR revealed that the bone regeneration could be improved via BMP/Runx2 pathway. Conclusion: The BPN-DFO hydrogel possesses potential tissue engineer material for ischemic bone defect treatment. However, furthermore studies are needed to testify the safety and efficacy of BPN-DFO hydrogel.

Radix Rehmanniae Praeparata promotes bone fracture healing through activation of TGF-ß signaling in mesenchymal progenitors.

BACKGROUND: Radix Rehmanniae Praeparata (RR), the steamed roots of Rehmannia glutinosa, is a traditional Chinese medicine with the function of kidney-nourishing, and it has been safety used for centuries to treat bone-related disorders. The aim of this study is to investigate the positive effect and underlying mechanism of RR enhancing bone fracture healing in mouse model. METHODS: Ten-week-old C57BL/6J mice were subjected to a unilateral open transverse tibial fracture and provided a daily treatment of RR. Bone samples were harvested for tissue analyses including x-ray, µCT, histology, histomorphometry, biomechanical testing, immunohistochemical (IHC) and quantitative gene expression analysis. To determine the role of TGF-ß in accelerating fracture healing effect of RR, aforementioned experiments were performed on Gli1-CreER; Tgfbr2 flox/flox (Tgfbr2Gli1ER) conditional knockout mice. RESULTS: RR promoted bone fracture healing and strengthened bone intensity in wild-type and Cre- mice with the activation of TGF-ß/Smad2 signaling, on the contrary, RR failed to accelerating fracture healing in Tgfbr2Gli1ER mice. CONCLUSION: RR promotes bone fracture healing by intensify the contribution of Gli1+ cells on bone and cartilage formation mainly in TGF-ß-dependent manner. RR is an alternative option for clinical treatment of fracture.

Photobiomodulation Therapy Associated with Heterologous Fibrin Biopolymer and Bovine Bone Matrix Helps to Reconstruct Long Bones.

Bone defects cause aesthetic and functional changes that affect the social, economic and especially the emotional life of human beings. This complication stimulates the scientific community to investigate strategies aimed at improving bone reconstruction processes using complementary therapies. Photobiomodulation therapy (PBMT) and the use of new biomaterials, including heterologous fibrin biopolymer (HFB), are included in this challenge. The objective of the present study was to evaluate the influence of photobiomodulation therapy on bone tibial reconstruction of rats with biomaterial consisting of lyophilized bovine bone matrix (BM) associated or not with heterologous fibrin biopolymer. Thirty male rats were randomly separated into three groups of 10 animals. In all animals, after the anesthetic procedure, a noncritical tibial defect of 2 mm was performed. The groups received the following treatments: Group 1: BM + PBMT, Group 2: BM + HFB and Group 3: BM + HFB + PBMT. The animals from Groups 1 and 3 were submitted to PBMT in the immediate postoperative period and every 48 h until the day of euthanasia that occurred at 14 and 42 days. Analyses by computed microtomography (µCT) and histomorphometry showed statistical difference in the percentage of bone formation between Groups 3 (BM + HB + PBMT) and 2 (BM + HFB) (26.4% ± 1.03% and 20.0% ± 1.87%, respectively) at 14 days and at 42 days (38.2% ± 1.59% and 31.6% ± 1.33%, respectively), and at 42 days there was presence of bone with mature characteristics and organized connective tissue. The µCT demonstrated BM particles filling the defect and the deposition of new bone in the superficial region, especially in the ruptured cortical. It was concluded that the association of PBMT with HFB and BM has the potential to assist in the process of reconstructing bone defects in the tibia of rats.

In-situ forming chitosan implant-loaded with raloxifene hydrochloride and bioactive glass nanoparticles for treatment of bone injuries: Formulation and biological evaluation in animal model.

In-situ forming implants receive great attention for repairing serious bone injuries. The aim of the present study was to prepare novel chitosan in-situ forming implants (CIFI) loaded with bioactive glass nanoparticles and/or raloxifene hydrochloride (RLX). Incorporating raloxifene hydrochloride (RLX) as a selective estrogen receptor modulator was essential to make use of its anti-resorptive properties. The prepared formulae were tested for their in-vitro gelation time, drug release, injectability, rheological properties, erosion rate and morphological properties. Results revealed that the formulation composed of 1% (w/v) chitosan with 2% (w/v) NaHCO3 and 1% (w/v) bioactive glass nanoparticles (CIFI-BG) possessed the most sustained drug release profile which extended over four months with low burst release effect compared to the same formulation lacking bioactive glass nanoparticles (CIFI). Selected formulations were tested for their ability to enhance bone regeneration in induced puncture in rate tibia. Results declared that these formulations were able to enhance bone regeneration after 12 weeks in comparison to the untreated tibial punctures and that containing bioactive glass could be considered as novel approach for treatment of serious bone injuries which require long term treatment and internal mechanical bone support during healing.

Guhong Injection promotes fracture healing by activating Wnt/beta-catenin signaling pathway in vivo and in vitro.

Guhong Injection (GHI), composed of aceglutamide and safflower aqueous extract, has been applied to the clinical treatment of orthopedic diseases, but the relevant mechanism by which GHI exerts effects on bone remodeling has not been reported. In the present study, we investigated the effects of various concentrations of GHI (2.5, 5 and 10 ml/kg) in accelerating rat tibia healing progress by observing haematoxylin and eosin (HE) stained sections, detecting the activity of bone metabolism biochemical markers such as bone morphogenetic protein-2 (BMP-2), transforming growth factor-beta (TGF-beta), osteocalcin (OC) and C-terminal crosslinking telopeptide of type Ⅰ collagen (CTX-1) in rat serum, as well as measuring the expressions of collagen I (COL-1) and collagen II (COL-2) in rat tibia. Also, we investigated the effects of different concentrations of GHI (30, 60 and 90 µl/ml) on the proliferation and differentiation of osteoblasts (OBs) through proliferating cell nuclear antigen (PCNA), alkaline phosphatase (ALP) and type I collagen (COL-1). At the same time, the expression of important factors of Wnt/beta-catenin signaling pathway including Wnt-3a, beta-catenin, disheveled-1 (Dvl-1), glycogen synthase kinases-3beta (GSK-3beta), lymphoid enhancing factor-1 (LEF-1) and axis inhibition protein-2 (Axin-2) after GHI intervention was detected by quantitative real-time PCR (q-PCR), immunohistochemistry and Western blotting. In vivo, rats of tibia fracture model treated with intraperitoneal injection (ip) of GHI had more mature fibroblasts, as well as shorter period formation of new bone. The levels of BMP-2, TGF-beta and OC in rat serum were significantly up-regulated, while the level of CTX was down-regulated. After 4 weeks of drug treatment, the level of COL-1 in the rat tibia increased, but there was no significant change in the level of COL-2. In vitro, after drug intervention, the number of OBs increased significantly, the activities of PCNA, ALP and COL-1 were enhanced. Treatment with GHI increased the mRNA and protein expression of Wnt-3a, beta-catenin, Dvl-1 and LEF-1, and decreased the expression of mRNA of Axin-2 and GSK-3beta. All results demonstrate that GHI accelerates the proliferation of OBs and shortens the recovery time of bone structure, and the Wnt/beta-catenin signaling pathway is involved in the regulation process.

Early outcome of culture-negative infection in open fractures of the lower limb: A prospective study.

Background: Culture-negative infections in open long bone fractures are frequently encountered in clinical practice. We aimed to identify the rate and outcome of culture-negative infections in open long bone fractures of lower limb. Methodology: A prospective cohort study was conducted from November 2015 to May 2017 on Gustilo and Anderson Grade III open long bone fractures of the lower limb. Demographic data, injury details, time from injury to receiving antibiotics and index surgical procedure were noted. Length of hospital stay, number of additional surgeries and occurrence of complications were also noted. Patients with infected open fractures were grouped as culture positive or culture negative depending on the isolation of infecting microorganisms in deep intraoperative specimen. The clinical outcome of these two groups was statistically analysed. Results: A total of 231 patients with 275 open fractures involving the femur, tibia or fibula were studied. There was clinical signs of infection in 84 patients (36.4%) with 99 fractures (36%). Forty-three patients (51.2%) had positive cultures and remaining 41 patients had negative cultures (48.8%). The rate of culture-negative infection in open type III long bone fractures in our study was 17.7%. There was no statistical difference in the clinical outcome between culture-negative and culture-positive infections. Conclusion: Failure to identify an infective microorganism in the presence of clinical signs of infection is routinely seen in open fractures and needs to be treated aggressively.

Nanolayered hybrid mediates synergistic co-delivery of ligand and ligation activator for inducing stem cell differentiation and tissue healing.

Cellular behaviors, such as differentiation, are regulated by complex ligation processes involving cell surface receptors, which can be activated by various divalent metal cations. The design of nanoparticle for co-delivery of ligand and ligation activator can offer a novel strategy to synergistically stimulate ligation processes in vivo. Here, we present a novel layered double hydroxide (LDH)-based nanohybrid (MgFe-Ado-LDH), composed of layered MgFe hydroxide nanocarriers sandwiching the adenosine cargo molecule, maintained through an electrostatic balance, to co-deliver the adenosine (Ado) ligand from the interlayer spacing and the Mg2+ ion (ligation activator) through the dissolution of the MgFe nanocarrier itself. Our findings demonstrate that the MgFe-Ado-LDH nanohybrid promoted osteogenic differentiation of stem cells through the synergistic activation of adenosine A2b receptor (A2bR) by the dual delivery of adenosine and Mg2+ ions, outperforming direct supplementation of adenosine alone. Furthermore, the injection of the MgFe-Ado-LDH nanohybrid and stem cells embedded within hydrogels promoted the healing of rat tibial bone defects through the rapid formation of fully integrated neo-bone tissue through the activation of A2bR. The newly formed bone tissue displayed the key features of native bone, including calcification, mature tissue morphology, and vascularization. This study demonstrates a novel and effective strategy of bifunctional nanocarrier-mediated delivery of ligand (cargo molecule) and activation of its ligation to receptor by the nanocarrier itself for synergistically inducing stem cell differentiation and tissue healing in vivo, thus offering novel design of biomaterials for regenerative medicine.

Strontium ranelate stimulates trabecular bone formation in a rat tibial bone defect healing process.

Strontium ranelate treatment is known to prevent fractures. Here, we showed that strontium ranelate treatment enhances bone healing and affects bone cellular activities differently in intact and healing bone compartments: Bone formation was increased only in healing compartment, while resorption was reduced in healing and normal bone compartments. INTRODUCTION: Systemic administration of strontium ranelate (SrRan) accelerates the healing of bone defects; however, controversy about its action on bone formation remains. We hypothesize that SrRan could affect bone formation differently in normal mature bone or in the bone healing process. METHODS: Proximal tibia bone defects were created in 6-month-old female rats, which orally received SrRan (625 mg/kg/day, 5/7 days) or vehicle (control groups) for 4, 8, or 12 weeks. Bone samples were analyzed by micro-computed tomography and histomorphometry in various regions, i.e., metaphyseal 2nd spongiosa, a region close to the defect, within the healing defect and in cortical defect bridging region. Additionally, we evaluated the quality of the new bone formed by quantitative backscattered electron imaging and by red picosirius histology. RESULTS: Healing of the bone defect was characterized by a rapid onset of bone formation without cartilage formation. Cortical defect bridging was detected earlier compared with healing of trabecular defect. In the healing zone, SrRan stimulated bone formation early and laterly decreased bone resorption improving the healing of the cortical and trabecular compartment without deleterious effects on bone quality. By contrast, in the metaphyseal compartment, SrRan only decreased bone resorption from week 8 without any change in bone formation, leading to little progressive increase of the metaphyseal trabecular bone volume. CONCLUSIONS: SrRan affects bone formation differently in normal mature bone or in the bone healing process. Despite this selective action, this led to similar increased bone volume in both compartments without deleterious effects on the newly bone-formed quality.

The effects of low-level laser therapy on the healing of bone defects in streptozotocin-induced diabetic rats: A histological and morphometric evaluation.

BACKGROUND: The aim of the present study was to evaluate the effects of low-level laser therapy (LLLT) on the healing of bone defects in rats with streptozotocin (STZ)-induced DM. METHODS: 28 male Sprague-Dawley rats were used in this study. 14 animals received a single dose of STZ intraperitoneally (65 mg/kg) to induce Type I DM, whereas others were injected only with sterile saline solution. Four weeks later, standard bone defects were created in the tibiae of rats. Surgical wounds in one group from each of the diabetic and non-diabetic animals were irradiated with diode laser for every other day for 4 weeks and they were described as DM + LLLT and CONT + LLLT groups, respectively. Remaining two groups received no laser treatment. New bone formation, osteoblast and blood vessel counts were calculated in histologic sections. RESULTS: DM group had significantly smaller bone area and lower blood vessel count when compared to DM + LLLT, CONT and CONT + LLLT groups (p < 0.05 for each). CONT and CONT + LLLT groups had significantly larger bone area than DM + LLLT group (p < 0.05 for both). CONCLUSIONS: LLLT application promoted vascularization and new bone formation in animals with DM to a limited extent, since it was unable to support the healing process up to the level of non-diabetic animals.

Growth performance parameters, bone calcification and immune response of in ovo injection of 25-hydroxycholecalciferol and vitamin K3 in male ross 308 broilers.

This experiment aimed to evaluate the effects of in ovo injection of 25-hydroxycholecalciferol (25-OH-D3) and Vitamin K3 on growth performance, bone calcification and immune system responses in male Ross 308 broilers. Twelve treatment groups with a total number of 768 experimental hatching eggs, four replications and 16 eggs in each replication were selected to form a completely randomized design of factorial arrangement. Treatments included: (1) distilled water, (2) 0.4 µg D3, (3) 0.4 µg D3 + 2 µg K3, (4) 0.4 µg D3 + 6 µg K3, (5) 0.6 µg D3, (6) 0.6 µg D3 + 2 µg K3, (7) 0.6 µg D3 + 6 µg K3, (8) 0.8 µg D3, (9) 0.8 µg D3 + 2 µg K3, (10) 0.8 µg D3 + 6 µg K3, (11) 2 µg K3 and (12) 6 µg K3. Eggs were transferred to corresponding hatching baskets on the 18th day of incubation and received 0.5 ml of experimental solutions specific to each treatment. The results of our experiments showed that Treatment No. 4 ranked the best out of those administered; holding the highest level of weight gain, feed intake during the breeding period (grower and finisher), bone calcium and phosphorus concentration, and tibia fractural force, (p < 0.05). Treatment No. 4 also showed a significant increase in antibody titer against the SRBC. Maximum stimulation to PHA injection also belonged to this treatment. In contrast, treatment No. 1 held the greatest alkaline phosphates amount (p < 0.05). No improvements were observed in calcium egg shells compared to the control group. Our data implies that appropriate levels of Vitamins D3 and K3 in ovo injection has beneficial effects on growth performance, immune system and bone development.

Effects of Adding Neuromuscular Electrical Stimulation to Traditional Military Amputee Rehabilitation.

BACKGROUND: Traumatic transtibial amputations lead to an early decline in the use and weight bearing of the residual limb. These changes result in progressive quadriceps muscle atrophy with strength loss that affects standing and walking. Neuromuscular electrical stimulation (NMES) may be useful as an adjunct to amputee prosthetic rehabilitation to maintain quadriceps muscle strength and mass. The objective of this pilot study was to compare the effects of a home-based NMES rehabilitation program plus the traditional military amputee rehabilitation program (TMARP) to the effects of TMARP alone on quadriceps muscle strength, functional mobility, and pain in military service members after a combat-related lower extremity amputation. METHODS: In total, 44 participants, aged 19 to 46 years, with a unilateral transtibial amputation were randomly assigned to the TMARP plus NMES (n = 23) or to TMARP alone (n = 21). Both groups received 12 weeks of the traditional amputee rehabilitation, including pre- and postprosthetic training. Those in the NMES group also received 12 weeks of NMES, 15 to 20 minutes/day, 5 days a week. Participants were tested at 3-week intervals during the study (baseline, 3, 6, 9, and 12 weeks) for muscle strength and pain. For functional measures, they were tested after receiving their prosthesis and at study completion (weeks 6 and 12). RESULTS: In both groups, residual limb quadriceps muscle strength and pain severity improved from baseline to 12 weeks. The NMES plus TMARP group showed greater strength than the TMARP alone group at 3 weeks, before receiving the prosthesis. However, 6 weeks after receiving their prosthesis, there was no group difference in the residual limb strength. Functional mobility improved in both groups between weeks 6 and 12 with no difference between the two treatment groups. DISCUSSION: A home-based NMES intervention with TMARP worked at improving residual limb strength, pain, and mobility. NMES seemed most effective in minimizing strength loss in the amputated leg before receiving the prosthesis. Further research on amputation rehabilitation is warranted as NMES may accelerate recovery post amputation.

Ustilago echinata: Infection in a Mixed Martial Artist Following an Open Fracture.

Ustilago, a common fungal parasite of grains, is infrequently isolated as a pathogen in humans. We describe a case of Ustilago echinata infection following an open distal tibia fracture, review the current literature of this genus as a cause of invasive fungal infection in humans, and discuss management issues.

Bone regeneration of hydroxyapatite/alumina bilayered scaffold with 3 mm passage-like medullary canal in canine tibia model.

The aim of this study was to evaluate the bone regeneration of hydroxyapatite (HA)/alumina bilayered scaffold with a 3 mm passage-like medullary canal in a beagle tibia model. A porous HA/alumina scaffold was fabricated using a polymeric template-coating technique. HA/alumina scaffold dimensions were 10 mm in outer diameter, 20 mm in length, and with either a 3 mm passage or no passage. A 20 mm segmental defect was induced using an oscillating saw through the diaphysis of the beagle tibia. The defects of six beagles were filled with HA/alumina bilayered scaffolds with a 3 mm passage or without. The segmental defect was fixated using one bone plate and six screws. Bone regeneration within the HA/alumina scaffolds was observed at eight weeks after implantation. The evaluation of bone regeneration within the scaffolds after implantation in a beagle tibia was performed using radiography, computerized tomography (CT), micro-CT, and fluorescence microscopy. New bone successfully formed in the tibia defects treated with 3 mm passage HA/alumina scaffolds compared to without-passage HA/alumina scaffolds. It was concluded that the HA/alumina bilayered scaffold with 3 mm passage-like medullary canal was instrumental in inducing host-scaffold engraftment of the defect as well as distributing the newly formed bone throughout the scaffold at 8 weeks after implantation.

Reparación ósea utilizando sulfato de calcio en defectos óseos de tibia de conejos / Bone repair using calcium sulfate in bone defects of rabbit tibiae

La regeneración ósea en reconstrucción del proceso alveolar junto al uso de implantes oseointegrables son ampliamente utilizados, existiendo una amplia variabilidad de productos. El objetivo de esta investigación es estudiar la reparación ósea asociada a un sustituto óseo a base de sulfato de calcio cubierto con membrana biológica en defectos creados en tibia de conejos. Se seleccionaron 12 conejos de entre 3 y 6 meses para ser intervenidos; de acuerdo a protocolos de anestesia ya conocidos se realizó la técnica con acceso a ambas tibias donde se realizaron 2 defectos de 2,6 mm de diámetro; se formaron cuatro grupos siendo el grupo I de relleno con coágulo sanguíneo, grupo II relleno con coagulo cubierto con membrana de colágeno, grupo III relleno con sulfato de calcio y grupo IV relleno con sulfato de calcio cubierto con membrana biológica. Se realizó la eutanasia a los 21 y 42 días y posteriormente se procedió a procesar y analizar láminas histológicas con tinción de hematoxilina y eosina. Se realizó la histomorfometría comparativa analizando los datos con prueba ANOVA y prueba de Turkey considerando un valor de p<0,05 para significancia estadística. Los resultados demostraron que todos los defectos mostraron patrones regulares de reparación ósea; los grupos rellenados con coágulo mostraron formación ósea estadísticamente menor que el presentado por los defectos rellenos con el sulfato de calcio, aunque estos últimos presentaron mayores indicadores de presencia de proceso inflamatorio; el grupo IV fue el que presentó los mejores niveles de reparación ósea a los 21 y 42 días. Se concluye que la reparación ósea en defectos menores es viable de ser realizada con este biomaterial y que la cobertura con membrana de colágeno puede ser útil en la regeneración ósea guiada.

Bone regeneration in the alveolar process and dental implant are widely used and there are a lot of different products. The aim of this research was to know the bone reparation associated to bone substitute with calcium sulfate and a biological membrane in created defects in rabbit tibiae. Were selected 12 rabbit between 3 and 6 month to be operated; using previous anesthesia protocols was do it a surgical defect in the right and left tibiae with 2.6 mm diameter; four groups were created: group I with blood clot fill, group II with blood clot fill plus biological membrane, group III with calcium sulfate and group IV with calcium sulfate plus biological membrane. The euthanasia was made in 21 and 42 days before surgery and was obtained histological plate using hematoxillin and eosin. The histomorphometry was made and statistical analysis using ANOVA and Turkey test with p<0.05 to obtain statistical differences. Were observed in the all created defects a regular bone reparation; the group I and II, with blood clot, showed a minor bone reparation than group III and IV with calcium sulfate, but these last one show an important inflammatory process; the group IV presented the better results at 21 and 42 euthanasia days in term of bone formation. It´s conclude that calcium sulfate can be used in bone reparation of minor defects and the biological membrane can be used in guide bone regeneration with success.

Five-day, low-level laser therapy for sports-related lower extremity periostitis in adult men: a randomized, controlled trial.

Periostitis in the lower leg caused by overexercise is a universal problem in athletes and runners. The purpose of this study was to observe the functional improvement of the lower limbs upon rehabilitation low-level laser therapy (LLLT). All medical data were gathered from enrolled adults with sports-related lower leg pain. A total of 54 patients underwent triple-phase bone scans using skeletal nuclear scintigraphy, which confirmed periostitis in their lower limbs. The patients were then randomly divided into two groups: one group received laser therapy (N = 29) and the other group (N = 25) received an equivalent placebo treatment (a drug or physical therapy). Treatment protocol commenced with rehabilitation intervention and LLLT was performed three times daily for 5 days at a dosage of 1.4 J/cm(2). A Likert-type pain scale was used to evaluate the severity of pain. Balance function, including postural stability testing (PST) and limits of stability (LOS), was also performed to evaluate the function outcome. Patients experienced a significant improvement in pain by day 2 or day 5 after starting LLLT, but here was no significant difference in pain scale between the measurements before (baseline) and after LLLT. Comparing the PST, the group differences of dynamic vs. static testings ranged from -18.54 to -50.22 (compared 12, 8, 4, 3, 2, 1 to 0, all p < 0.0001), and the PST after LLLT were 3.73 units (p = 0.0258) lower than those of before LLLT. Comparing the LOS, the group differences of dynamic vs. static testing were similar to those in PST, and the relationship between LOS and groups only varied with the direction control during dynamic testing in direction at backward/right vs. right (p < 0.0001). LLLT had a positive effect on proprioception in patients with lower limb periostitis. Larger, better controlled studies are needed to determine what specific effects LLLT has on the function of proprioception.

Histometric analysis and topographic characterization of cp Ti implants with surfaces modified by laser with and without silica deposition.

Biologic behavior of the bone tissue around implants with four different surfaces was evaluated. The surfaces were: modified by laser (LS); modified by laser with sodium silicate deposition (SS); and commercially available surfaces modified by acid etching (AS) and machined surface (MS). Topographic characterization of the surfaces was performed by scanning electron microscopy (SEM)- energy dispersive X-ray spectrometry (EDX) before experimental surgery. Thirty rabbits received 60 implants in their right and left tibias, 1 implant of each surface being placed in each tibia. The analyzed periods were 4, 8, and 12 weeks postoperatively. Histometric analysis was performed evaluating bone interface contact (BIC) and bone area (BA). The results obtained were submitted to the analysis of variance and the Tukey t-test. The elemental mapping was evaluated by means of SEM at 4 weeks postoperatively. The topographic characterization showed differences between the analyzed surfaces. Generally, the BIC and BA of LS and SS implants were statistically higher than those of AS and MS in most of the analyzed periods. Elemental mapping showed high peaks of calcium and phosphorous in all groups. Based on the present methodology, it may be concluded that experimental modifications LS and SS accelerated the stages of the bone tissue repair process around the implants, providing the highest degree of osseointegration.