scholarly journals Enhancing the Efficiency of Distraction Osteogenesis through Rate-Varying Distraction: A Computational Study

2021 ◽  
Vol 22 (21) ◽  
pp. 11734
Author(s):  
Ruisen Fu ◽  
Yili Feng ◽  
David Bertrand ◽  
Tianming Du ◽  
Youjun Liu ◽  
...  
Keyword(s):  
Bone Regeneration ◽  
Distraction Osteogenesis ◽  
Soft Tissues ◽  
Treatment Time ◽  
Computational Study ◽  
Healing Time ◽  
Tissue Differentiation ◽  
High Rate ◽  
Overall Treatment Time ◽  
Consolidation Phase

Distraction osteogenesis (DO) is a mechanobiological process of producing new bone and overlying soft tissues through the gradual and controlled distraction of surgically separated bone segments. The process of bone regeneration during DO is largely affected by distraction parameters. In the present study, a distraction strategy with varying distraction rates (i.e., “rate-varying distraction”) is proposed, with the aim of shortening the distraction time and improving the efficiency of DO. We hypothesized that faster and better healing can be achieved with rate-varying distractions, as compared with constant-rate distractions. A computational model incorporating the viscoelastic behaviors of the callus tissues and the mechano-regulatory tissue differentiation laws was developed and validated to predict the bone regeneration process during DO. The effect of rate-varying distraction on the healing outcomes (bony bridging time and bone formation) was examined. Compared to the constant low-rate distraction, a low-to-high rate-varying distraction provided a favorable mechanical environment for angiogenesis and bone tissue differentiation, throughout the distraction and consolidation phase, leading to an improved healing outcome with a shortened healing time. These results suggest that a rate-varying clinical strategy could reduce the overall treatment time of DO and decrease the risk of complications related to the external fixator.

scholarly journals Intermolar Mandibular Distraction Osteogenesis—A Preliminary Report

2021 ◽  
Vol 11 (9) ◽  
pp. 4118
Author(s):  
Suen A. N. Lie ◽  
Britt H. B. T. Engelen ◽  
Veronique C. M. L. Timmer ◽  
Nico M. P. Vrijens ◽  
Paolo Asperio ◽  
...  
Keyword(s):  
Distraction Osteogenesis ◽  
Treatment Time ◽  
Average Length ◽  
Case Series ◽  
Growth Spurt ◽  
Overall Treatment Time ◽  
Mandibular Distraction ◽  
Mandibular Distraction Osteogenesis ◽  
Root Fractures

Background: Dental Class II is the most common indication for combined orthodontic-orthognathic treatment. Intermolar mandibular distraction osteogenesis (IMDO) treatment was performed during the growth spurt, to avoid surgery at a later age. The aim of this study is to present our first experience with IMDO. Methods: This is a retrospective case series of patients who underwent an IMDO. All patients showed mandibular retrognathism, and orthodontic treatment with functional appliances was not successful. Results: In total, 20 patients (mean age of 14.8 years (SD = 0.9 ys) were included. All patients achieved a Class I occlusion. An average length gain of 9.6 mm (SD = 3.7 mm) was reached. In one patient an abscess occurred. Nine patients presented with root fractures of the second molar; three were lost, one treated endodontically. The average time between insertion and removal of the distractors was 4.6 months (SD = 1.5 mths). In one case a premature consolidation was seen. Conclusion: We achieved satisfactory results with IMDO, although undesirable effects occurred. An advantage is the manageable overall treatment time. Open questions concern the occurrence of root fractures. Furthermore, the question of long-term stability is open. The question of dynamic distraction treatment in relation to temporomandibular joint changes can only be answered in the long term.

EVALUATION OF RESULTS OF THE IMPLANT PLACEMENT IMMEDIATELY AFTER TOOTH EXTRACTION

2018 ◽  
Vol 8 (6) ◽  
pp. 196-202
Author(s):  
Phuc Ngo Vinh ◽  
Tai Tran Tan ◽  
Duong Huynh Van
Keyword(s):  
Success Rate ◽  
Dental Implants ◽  
Tooth Extraction ◽  
Treatment Time ◽  
Clinical Results ◽  
High Rate ◽  
Overall Treatment Time ◽  
Implant Placement ◽  
The Status ◽  
Immediate Implant

Background: The concept of immediate implant loading has recently become popular due to less trauma, reduction in overall treatment time, decrease in hard and soft tissue resorption, increase in patient’s acceptance, along with better function, aesthetics and has a psychological satisfaction to the patient. The purpose of this study is to evaluate the results of implant placement immediately after tooth extraction. Materials and method: The study consisted of 32 patients with 43 implants have been placed immediately after tooth extraction in the Odonto-Maxillo-Facial Hospital of Ho Chi Minh City. Evaluation results after dental implants 1 week, 1 month, 3 months, 6 months. Results: Good clinical results after 1 week was 55.8%, after 3 months and 6 months were 100%. After 1 week of implant placement, good healing took 59.4%. After 1 month, 3 months and 6 months, 100% of the patients are well healed. After 3 months, 6 months without any implant has the status of shaky. Most dental implants have good levels of bone graft. The level of good after 3 months of implants was 72.1% and after 6 months all cases are good. The success rate for dental implants was up to 97.7%, failing only 2.3%. After 3 months the implants had a good level of 72.1% and after 6 months, all cases were good. Patients with success in implant placement accounted for a high rate of 97.7%, failure only accounted for 2.3%. Conclusions: Success rate in immediate implant is high. It is necessary to develop this method to restore lost teeth to achieve optimum results. Key words: Dental implant, immediate implant after tooth extraction

scholarly journals Canines on a Fast Track: Canine Distalization by Dentoalveolar Distraction Osteogenesis

2013 ◽  
Vol 2 (1) ◽  
pp. 44-49 ◽  
Author(s):  
Amit Bhardwaj ◽  
Anup Belludi ◽  
Bhavna Virang ◽  
Sagar Padmawar ◽  
Parag Virang
Keyword(s):  
Distraction Osteogenesis ◽  
Efficient Method ◽  
Slow Rate ◽  
Fast Track ◽  
Tooth Movement ◽  
Treatment Time ◽  
Overall Treatment Time ◽  
Canine Retraction ◽  
Rapid Movement ◽  
Canine Distalization

ABSTRACT Conventional techniques for biological tooth movement is routinely achieved at a slow rate and in high anchorage cases where individual canine retraction is indicated lasts for 6 to 8 months, followed by retraction of the incisors. Hence, the overall treatment time taken is about 18 to 24 months. Rapid canine distalization through dentoalveolar distraction (DAD) technique can be achieved within 2 to 3 weeks with this technique. This clinically efficient method significantly reduces the overall treatment time without causing any serious discomfort or damage to the patient. In this technique osteotomies surrounding the canines are made to achieve rapid movement of the canines within the dentoalveolar segment, in compliance with distraction osteogenesis principles. How to cite this article Virang B, Belludi A, Bhardwaj A, Padmawar S, Virang P. Canines on a Fast Track: Canine Distalization by Dentoalveolar Distraction Osteogenesis. Int J Experiment Dent Sci 2013;2(1):44-49.

scholarly journals Role of distraction osteogenesis in craniomaxillofacial surgery

2016 ◽  
Vol 1 (2) ◽  
pp. 97-103 ◽  
Author(s):  
Nicole Ernst ◽  
Nicolai Adolphs
Keyword(s):  
Distraction Osteogenesis ◽  
Soft Tissues ◽  
Limb Lengthening ◽  
Craniofacial Skeleton ◽  
Craniomaxillofacial Surgery ◽  
Growth Deficiency ◽  
Distraction Device ◽  
Consolidation Phase ◽  
Gradual Expansion

AbstractIn the field of orthopedic surgery, distraction osteogenesis (DO) is well known for limb lengthening procedures or secondary corrective surgery in the fracture treatment of the extremities. The principle of gradual expansion of bone and surrounding soft tissues as originally described by G.A. Ilizarov is also applicable to the craniofacial skeleton when growth deficiency is present, and the patients affected by craniofacial or dentofacial anomalies may require distraction procedures. The surgical management is comparable. After osteotomy and the mounting of a specific craniomaxillofacial distraction device, active distraction is started after a latency phase of several days, with a distraction rate of up to 1 mm/day until the desired amount of distraction has been achieved. Subsequently, distractors are locked to provide appropriate stability within the distraction zone for callus mineralization during the consolidation phase of 3–6 months, which is followed by a further remodeling of the bony regenerate. After 14 years of clinical application, the role and significance of craniomaxillofacial DO are discussed after reviewing the files of all patients who were treated by craniomaxillofacial distraction procedures.

Vital Tooth Whitening Techniques. A literature Review

2020 ◽  
Vol 02 ◽  
Author(s):  
Pia Chatterjee Kirk
Keyword(s):  
Soft Tissues ◽  
Treatment Time ◽  
Tooth Bleaching ◽  
Tooth Whitening ◽  
Easy Method ◽  
Tooth Structure ◽  
Dental Esthetics ◽  
Total Treatment Time ◽  
Restorative Materials ◽  
Total Treatment

Background: Vital tooth whitening has become an integral part of esthetic dentistry and remains one of the safest and most economic options today to improve dental esthetics without removing tooth structure. The tooth whitening materials have evolved into three categories: dentist-prescribed/dispensed (in office and patient home-use), and over-thecounter purchased and applied by patients. Objective: This review outlines the latest advances in dentist prescribed vital teeth whitening techniques, effects on tooth structure, soft tissues, and dental restoratives. Areas requiring additional research are also discussed. Methods: Electronic and manual literature search was conducted for key words such as tooth bleaching, and dental bleaching techniques using PubMed/MEDLINE, followed by manual selection of the studies that included whitening procedures in vital teeth. Results: The two main whitening agents are carbamide peroxide (CP) and hydrogen peroxide (HP or H2O2) whose concentration, duration of contact, and total treatment time can alter results. In addition, factors including the type of stain, and age of patient can affect results. Although whitening agents can affect tooth structure, restorative materials, and gingival tissues, the changes are temporary or can be treated using minimally invasive techniques. Conclusion: Areas requiring further research include the actual mechanism of whitening, its effect on tooth structure and restorative materials, and the development of an easy method to quantitate the degree of whitening in the dental office.

scholarly journals Systemic Administration of G-CSF Accelerates Bone Regeneration and Modulates Mobilization of Progenitor Cells in a Rat Model of Distraction Osteogenesis

2021 ◽  
Vol 22 (7) ◽  
pp. 3505
Author(s):  
Flavy Roseren ◽  
Martine Pithioux ◽  
Stéphane Robert ◽  
Laure Balasse ◽  
Benjamin Guillet ◽  
...  
Keyword(s):  
Bone Regeneration ◽  
Progenitor Cells ◽  
Distraction Osteogenesis ◽  
Rat Model ◽  
Late Phase ◽  
Control Group ◽  
Bone Lengthening ◽  
Hematopoietic Stem ◽  
Osteoblast Activity ◽  
Positron Emission

Granulocyte colony-stimulating factor (G-CSF) was shown to promote bone regeneration and mobilization of vascular and osteogenic progenitor cells. In this study, we investigated the effects of a systemic low dose of G-CSF on both bone consolidation and mobilization of hematopoietic stem/progenitor cells (HSPCs), endothelial progenitor cells (EPCs) and mesenchymal stromal cells (MSCs) in a rat model of distraction osteogenesis (DO). Neovascularization and mineralization were longitudinally monitored using positron emission tomography and planar scintigraphy. Histological analysis was performed and the number of circulating HSPCs, EPCs and MSCs was studied by flow cytometry. Contrary to control group, in the early phase of consolidation, a bony bridge with lower osteoclast activity and a trend of an increase in osteoblast activity were observed in the distracted callus in the G-CSF group, whereas, at the late phase of consolidation, a significantly lower neovascularization was observed. While no difference was observed in the number of circulating EPCs between control and G-CSF groups, the number of MSCs was significantly lower at the end of the latency phase and that of HSPCs was significantly higher 4 days after the bone lengthening. Our results indicate that G-CSF accelerates bone regeneration and modulates mobilization of progenitor cells during DO.

Primary Human Liver Cells as Source for Modular Extracorporeal Liver Support - a Preliminary Report

2002 ◽  
Vol 25 (10) ◽  
pp. 1001-1005 ◽  
Author(s):  
I.M. Sauer ◽  
K. Zeilinger ◽  
N. Obermayer ◽  
G. Pless ◽  
A. Grünwald ◽  
...  
Keyword(s):  
Human Liver ◽  
Treatment Time ◽  
Liver Perfusion ◽  
Cell Mass ◽  
Liver Weight ◽  
Liver Cells ◽  
Liver Support ◽  
Overall Treatment Time ◽  
Human Liver Cells ◽  
Extracorporeal Liver Support

Cell-based extracorporeal liver support is an option to assist or replace the failing organ until regeneration or until transplantation can be performed. The use of porcine cells or tumor cell lines is controversial. Primary human liver cells, obtained from explanted organs found to be unsuitable for transplantation, are a desirable cell source as they perform human metabolism and regulation. The Modular Extracorporeal Liver Support (MELS) concept combines different extracorporeal therapy units, tailored to suit the individual and intra-individual clinical needs of the patient. A multi-compartment bioreactor (CellModule) is loaded with human liver cells obtained by 5-step collagenase liver perfusion. A cell mass of 400 g – 600 g enables the clinical application of a liver lobe equivalent hybrid organ. A detoxification module enables single pass albumin-dialysis via a standard high-flux dialysis filter, and continuous venovenuous hemodiafiltration may be included if required. Cells from 54 human livers have been isolated (donor age: 56 ± 13 years, liver weight: 1862 ± 556 g resulting in a viability of 55.0 ± 15.9%). These grafts were not suitable for LTx, due to steatosis (54%), cirrhosis (15%), fibrosis (9%), and other reasons (22%). Out of 36 prepared bioreactors, 10 were clinically used to treat 8 patients with liver failure. The overall treatment time was 7–144 hours. No adverse events were observed. Initial clinical applications of the bioreactor evidenced the technical feasibility and safety of the system.

An experimental and computational study to understand the lithium storage mechanism in molybdenum disulfide

Nanoscale ◽  
2014 ◽  
Vol 6 (17) ◽  
pp. 10243-10254 ◽  
Author(s):  
Uttam Kumar Sen ◽  
Priya Johari ◽  
Sohini Basu ◽  
Chandrani Nayak ◽  
Sagar Mitra
Keyword(s):  
Experimental Evidence ◽  
Lithium Ion Battery ◽  
Computational Study ◽  
Lithium Ion ◽  
Elemental Sulphur ◽  
High Rate ◽  
Discharge Process ◽  
Lithium Storage ◽  
Storage Mechanism ◽  
Battery Anode

Experimental evidence and theoretical correlation of the formation of elemental sulphur during the discharge process of MoS2, a high rate lithium ion battery anode.

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