scholarly journals MRI for the display of autologous onlay bone grafts during early healing—an experimental study

2020 ◽  
pp. 20200068
Author(s):  
Tabea Flügge ◽  
Ute Ludwig ◽  
Philipp Amrein ◽  
Florian Kernen ◽  
Kirstin Vach ◽  
...  

Objectives: Autologous bone grafts are the gold standard to augment deficient alveolar bone. Dimensional graft alterations during healing are not known as they are not accessible to radiography. Therefore, MRI was used to display autologous onlay bone grafts in vivo during early healing. Methods and materials: Ten patients with alveolar bone atrophy and autologous onlay grafts were included. MRI was performed with a clinical MR system and an intraoral coil preoperatively (t0), 1 week (t1), 6 weeks (t2) and 12 weeks (t3) postoperatively, respectively. The graft volumes were assessed in MRI by manual segmentation by three examiners. Graft volumes for each time point were calculated and dimensional alteration was documented. Cortical and cancellous proportions of bone grafts were assessed. The intraobserver and interobserver variability were calculated. Statistical analysis was performed using a mixed linear regression model. Results: Autologous onlay bone grafts with cortical and cancellous properties were displayed in vivo in eight patients over 12 weeks. The fixation screws were visible as signal voids with a thin hyperintense fringe. The calculated volumes were between 0.12–0.74 cm3 (t1), 0.15–0.73 cm3 (t2), and 0.17–0.64 cm3 (t3). Median changes of bone graft volumes of −15% were observed. There was no significant difference between the examiners (p = 0.3). Conclusions: MRI is eligible for the display and longitudinal observation of autologous onlay bone grafts. Image artifacts caused measurements deviations in some cases and minimized the precise assessment of graft volume. To the knowledge of the authors, this is the first study that used MRI for the longitudinal observation of autologous onlay bone grafts.

2018 ◽  
Vol 69 (2) ◽  
pp. 429-433
Author(s):  
Solyom Arpad ◽  
Cristian Trambitas ◽  
Ecaterina Matei ◽  
Eugeniu Vasile ◽  
Fodor Pal ◽  
...  

Osteoplasty, is a procedure mostly applied in complicated bone fractures. Nowadays this method is widely used in primary fracture treatment while the native bone graft is progressively replaced with various synthetic bone substitutes. From the numerous bone grafts we�d like to mention a representative of ceramics, the S53P4 bioactive glass. (BonAlive�). The aim of this study was to investigate the healing process of different fracture types generated on rabbit femurs. During this experiment we used seven common European rabbits. We separated these animals into two groups; in the first group we surgically generated a total fracture in the middle 1/3 of the femur, while in the second group, we produced only a bone defect on the femur. The osteoplasty was carried out with bioactive glass and autologous bone grafts. The radiographic follow-up was immediate after the operation and after 3, 6 and 7 weeks. The animals were euthanized after 19, 20 and 21 weeks, for histomorphometric examination of the femur. It was also studied the ionic release from the used bioactive glass at physiological pH and the etching of the glass was studied by Scanning Electron Microscopy.


Author(s):  
Camila Saggioro ◽  
Suelen Sartoretto ◽  
Isabelle Duarte ◽  
Adriana Alves ◽  
Helder Barreto ◽  
...  

In order to preserve alveolar bone thickness and width after extraction, clinical strategies have been adopted to reduce or eliminate the need for future surgical interventions to increase the alveolar ridge. The use of xenogeneic biomaterials has been increasing for such application. The association of bone substitutes with active oxygen-based materials, which is essential in the wound healing process, could accelerate the bone repair, optimizing the maintenance of alveolar architecture after extraction. However, the truth of this hypothesis is not clear. The present study aimed to compare the biological response to inorganic bovine bone graft Bonefill® (BF), associated or not with active oxygen-based gel Oral gel Blue ® m (BF+BM), in alveolar bone repair. Twenty female Wistar rats were randomly distributed, the left upper central incisor was extracted and the dental sockets were filled with BF in the control group (n=10), and with BF+BM in the experimental group (n=10). After 7- and 42-days’ post implantation (n=5), the animals were euthanized, and the samples were processed for descriptive histological and histomorphometric evaluations. The results showed no significant difference between the groups (p>0.05). Both groups presented a time-dependent increase of new formed bone and biosorption biomaterial (p=0.0001). While the biomaterial analyzed was considered compatible and osteoconductive, the association with Blue ® m gel did not improve or interfere with the bone repair after the experimental periods.


Nanomaterials ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 599 ◽  
Author(s):  
Chien-Chung Chen ◽  
Sheng-Yang Lee ◽  
Nai-Chia Teng ◽  
Hsin-Tai Hu ◽  
Pei-Chi Huang ◽  
...  

The guided tissue regeneration (GTR) membrane is a barrier intended to maintain a space for alveolar bone and periodontal ligament tissue regeneration but prevent the migration of fast-growing soft tissue into the defect sites. This study evaluated the physical properties, in vivo animal study, and clinical efficacy of hydrophilic PLA95/β-TCP GTR membranes prepared by electrospinning (ES). The morphology and cytotoxicity of ES PLA95/β-TCP membranes were evaluated by SEM and 3-(4,5-cimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) respectively. The cementum and bone height were measured by an animal study at 8 and 16 weeks after surgery. Fifteen periodontal patients were selected for the clinical trial by using a commercial product and the ES PLA95/β-TCP membrane. Radiographs and various indexes were measured six months before and after surgery. The average fiber diameter for this ES PLA95/β-TCP membrane was 2.37 ± 0.86 µm. The MTT result for the ES PLA95/β-TCP membrane showed negative for cytotoxicity. The significant differences in the cementum and bone height were observed between empty control and the ES PLA95/β-TCP membrane in the animal model (p < 0.05). Clinical trial results showed clinical attachment level (CAL) of both control and ES PLA95/β-TCP groups, with a significant difference from the pre-surgery results after six months. This study demonstrated that the ES PLA95/β-TCP membrane can be used as an alternative GTR membrane for clinical applications.


2013 ◽  
Vol 24 (3) ◽  
pp. 218-223 ◽  
Author(s):  
Luiz Guilherme P. Soares ◽  
Edival Barreto de Magalhaes Junior ◽  
Cesar Augusto B. Magalhaes ◽  
Cimara Fortes Ferreira ◽  
Aparecida Maria C. Marques ◽  
...  

Use of biomaterials and light on bone grafts has been widely reported. This work assessed the influence of low-level laser therapy (LLLT) on bone volume (BV) and bone implant contact (BIC) interface around implants inserted in blocks of bovine or autologous bone grafts (autografts), irradiated or not, in rabbit femurs. Twenty-four adult rabbits were divided in 8 groups: AG: autograft; XG: xenograft; AG/L: autograft + laser; XG/L: xenograft + laser; AG/I: autograft + titanium (Ti) implant; XG/I: xenograft + Ti implant; AG/I/L: autograft + Ti implant + laser; and XG/I/L: xenograft + Ti implant + laser. The animals received the Ti implant after incorporation of the grafts. The laser parameters in the groups AG/L and XG/L were λ=780 nm, 70 mW, CW, 21.5 J/cm 2 , while in the groups AG/I/L and XG/I/L the following parameters were used: λ=780 nm, 70 mW, 0.5 cm 2 (spot), 4 J/cm 2 per point (4), 16 J/cm 2 per session, 48 h interval × 12 sessions, CW, contact mode. LLLT was repeated every other day during 2 weeks. To avoid systemic effect, only one limb of each rabbit was double grafted. All animals were sacrificed 9 weeks after implantation. Specimens were routinely stained and histomorphometry carried out. Comparison of non-irradiated and irradiated grafts (AG/L versus AG and XG/L versus XG) showed that irradiation increased significantly BV on both grafts (p=0.05, p=0.001). Comparison between irradiated and non-irradiated grafts (AG/I/L versus AG/I and XG/I/L versus XG/I) showed a significant (p=0.02) increase of the BIC in autografts. The same was seen when xenografts were used, without significant difference. The results of this investigation suggest that the use of LLLT is effective for enhancing new bone formation with consequent increase of bone-implant interface in both autologous grafts and xenografts.


VASA ◽  
2020 ◽  
Vol 49 (4) ◽  
pp. 281-284
Author(s):  
Atıf Yolgosteren ◽  
Gencehan Kumtepe ◽  
Melda Payaslioglu ◽  
Cuneyt Ozakin

Summary. Background: Prosthetic vascular graft infection (PVGI) is a complication with high mortality. Cyanoacrylate (CA) is an adhesive which has been used in a number of surgical procedures. In this in-vivo study, we aimed to evaluate the relationship between PVGI and CA. Materials and methods: Thirty-two rats were equally divided into four groups. Pouch was formed on back of rats until deep fascia. In group 1, vascular graft with polyethyleneterephthalate (PET) was placed into pouch. In group 2, MRSA strain with a density of 1 ml 0.5 MacFarland was injected into pouch. In group 3, 1 cm 2 vascular graft with PET piece was placed into pouch and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. In group 4, 1 cm 2 vascular graft with PET piece impregnated with N-butyl cyanoacrylate-based adhesive was placed and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. All rats were scarified in 96th hour, culture samples were taken where intervention was performed and were evaluated microbiologically. Bacteria reproducing in each group were numerically evaluated based on colony-forming unit (CFU/ml) and compared by taking their average. Results: MRSA reproduction of 0 CFU/ml in group 1, of 1410 CFU/ml in group 2, of 180 200 CFU/ml in group 3 and of 625 300 CFU/ml in group 4 was present. A statistically significant difference was present between group 1 and group 4 (p < 0.01), between group 2 and group 4 (p < 0.01), between group 3 and group 4 (p < 0.05). In terms of reproduction, no statistically significant difference was found in group 1, group 2, group 3 in themselves. Conclusions: We observed that the rate of infection increased in the cyanoacyrylate group where cyanoacrylate was used. We think that surgeon should be more careful in using CA in vascular surgery.


Author(s):  
Tamilarasi G P ◽  
Sabarees G

Oxidation is an essential reaction in the human body, which determines the expression of proteins in the body. This results in the altered expression like rapid growth resulting in cancers and other disorders. Many synthetic drugs are available in the market that is effective in limiting the free radical generation and the reaction of radicals with cells. Unfortunately, all those synthetic drugs were found to cause side effects and adverse effects in the body. But given the accuracy of the predictability of the results and administration, this research focuses on testing the anti-oxidant efficiency in rat models testing the biochemical parameters. Investigations have also been done on the anti-oxidant activity of Tectona, but every research was concentrated to prove the anti-oxidant activity only. extract had been tested for anti-oxidant activity by estimating various tissue parameters and it showed better activity. As predicted, there is a significant difference in the and results which can be explained are due to the physiological conditions that exist inside the body.


Author(s):  
Miriam del Carmen Carrasco-Portugal ◽  
Francisco Javier Flores-Murrieta

Pharmaceutical alternatives are products with the same active moiety, but different salt, ester or pharmaceutical form. Regulatory agencies have different criteria for this kind of drug. The European Medicines Agency (EMA) accepts the generic substitution using these alternatives, whereas the Food and Drug Administration (FDA) only authorizes generic substitution of pharmaceutical equivalents. The objective of this paper is to describe some relevant aspects that should be considered before deciding on making a generic substitution with pharmaceutical alternatives. It is important to note that a pharmaceutical alternative must show no significant difference in the rate and extent of absorption (bioequivalence) in a well-conducted in vivo study when compared with the reference formulation. Current Mexican regulations state that generic substitution is possible using pharmaceutical alternatives when bioequivalence is demonstrated in in vivo studies conducted under the NOM-177-SSA1-2013 criteria. In conclusion, generic substitution with pharmaceutical alternatives is possible if these products demonstrate in vivo bioequivalence when compared with the reference product.


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