scholarly journals Development of a model of soft tissue simulation using ballistic gelatin for CBCT acquisitions related to dentomaxillofacial radiology research

2020 ◽  
pp. 20200191
Author(s):  
Eduarda Helena Leandro Nascimento ◽  
Rocharles Cavalcante Fontenele ◽  
Priscila de Azeredo Lopes ◽  
Gustavo Machado Santaella ◽  
Karla Faria Vasconcelos ◽  
...  

Objectives: To present the ballistic gelatin as a new material capable of simulating the soft tissues in cone-beam CT (CBCT) images. Methods: CBCT images of three piglet heads were acquired with their soft tissues intact (standard group). Subsequently, the piglet heads were fixed in a container using metallic pins and moulded with acrylic resin; the soft tissues were then removed and replaced by ballistic gelatin, with the same thickness of the original soft tissues. The images were evaluated by two oral radiologists, to check the adaptation on bone surfaces, thickness and density, penetration into large bone cavities and cancellous bone, and the presence of air bubbles using a 5-score scale. Additionally, an objective analysis was carried out by one oral radiologist. For each CBCT scan, three axial reconstructions were selected to represent the mandibular, occlusal, and maxillary levels. The mean and standard deviation (SD) of the grey values were calculated in four regions of interest determined on soft tissue areas and compared by two-way ANOVA. Results: The ballistic gelatin showed subjective scores ranging from good to excellent for all parameters evaluated. There was no significant difference in the mean and SD values of the grey values between ballistic gelatin and the gold standard groups for all levels (p > 0.05). Higher SD values were observed in the occlusal level for both groups (p < 0.05). Conclusions: Ballistic gelatin has visual and objective similarity with the gold standard. Thus, the ballistic gelatin is a promising material capable of simulating soft tissues in CBCT images.

2019 ◽  
Vol 30 (5) ◽  
pp. 585-592 ◽  
Author(s):  
Nicola Montemurro ◽  
Paolo Perrini ◽  
Vittoriano Mangini ◽  
Massimo Galli ◽  
Andrea Papini

OBJECTIVEOdontoid process fractures are very common in both young and geriatric patients. The axial trabecular architecture of the dens appears to be crucial for physiological and biomechanical function of the C1–2 joint. The aim of this study is to demonstrate the presence of a Y-shaped trabecular structure of the dens on axial CT and to describe its anatomical and biomechanical implications.METHODSFifty-four C2 odontoid processes in healthy subjects were prospectively examined for the presence of a Y-shaped trabecular structure at the odontocentral synchondrosis level with a dental cone beam CT scan. Length, width, and axial area of the odontoid process were measured in all subjects. In addition, measurements of the one-third right anterior area of the Y-shaped structure were taken.RESULTSThe Y-shaped trabecular structure was found in 79.6% of cases. Length and width of the odontoid process were 13.5 ± 0.6 mm and 11.2 ± 0.9 mm, respectively. The mean area of the odontoid process at the odontocentral synchondrosis was 93.5 ± 4.3 mm2, whereas the mean one-third right anterior area of the odontoid process at the same level was 29.3 ± 2.5 mm2. The mean area of the odontoid process and its length and width were similar in men and women (p > 0.05). No significant difference was found in the mean area of the odontoid process in people older than 65 years (94 ± 4.2 mm2) compared to people younger than 65 years (93.3 ± 4.4 mm2; p > 0.05).CONCLUSIONSThe authors identified a new anatomical entity, named the Y-shaped trabecular structure of the odontoid process, on axial CT scans. This structure appears to be the result of bone transformation induced by the elevated dynamic loading at the C1–2 level. The presence of the Y-shaped structure provides new insights into biomechanical responses of C2 under physiological loading and traumatic conditions.


2003 ◽  
Vol 40 (5) ◽  
pp. 544-549 ◽  
Author(s):  
Virgilio F. Ferrario ◽  
Chiarella Sforza ◽  
Claudia Dellavia ◽  
Gianluca M. Tartaglia ◽  
Davide Sozzi ◽  
...  

Objective To supply quantitative information about the facial soft tissues of adult operated patients with cleft lip and palate (CLP). Design, Setting, and Patients The three-dimensional coordinates of soft tissue facial landmarks were obtained using an electromagnetic digitizer in 18 Caucasian patients with CLP (11 males and 7 females aged 19 to 27 years) and 162 healthy controls (73 females and 89 males aged 18 to 30 years). From the landmarks, 15 facial dimensions and two angles were calculated. Data were compared with those collected in healthy individuals by computing z-scores. Two summary anthropometric measurements for quantifying craniofacial variations were assessed in both the patients and reference subjects: the mean z-score (an index of overall facial size), and its SD, called the craniofacial variability index (an index of facial harmony). Results In treated patients with CLP, facial size was somewhat smaller than in normal individuals, but in all occasions the mean z-score fell inside the normal interval (mean ± 2 SD). Almost all patients had a craniofacial variability index larger than the normal interval, indicating a global disharmonious appearance. Overall, in patients pronasale, subnasale, and pogonion were more posterior, the nose was shorter and larger, the face was narrower, and the soft tissue profile and upper lip were flatter than in the reference population. Conclusions The facial soft tissue structures of adult operated patients with CLP differed from those of normal controls of the same age, sex, and ethnic group. In this patient group, surgical corrections of CLP failed to provide a completely harmonious appearance, even if the deviations from the reference were limited. Further analyses of larger groups of patients are needed.


2010 ◽  
Vol 22 (1) ◽  
Author(s):  
Weko Adhiarto ◽  
Sunardhi Mangundjaja ◽  
Makmuri Yusuf ◽  
Bambang Pontjo

The wound healing process of the soft tissue aims to accelerate the closing of the wound by recurring, restoring the function, and minimizing the scar tissue. This process has to occur in the surgery process to obtain better-wound healing. The aim of this study was to know the stimulation effect of the wound dressing to accelerate the wound healing process of the soft tissue using Collagen (amino acid) and Amnion (proteinase inhibitors). This true experimental study was done to 36 mice (Sprague Dawley) that were divided into three different groups, two groups were the treatment groups and one group was the control group. Each group was adapted in Pathology Laboratory of Faculty of Veterinary Medicine Bogor Agricultural University. All of the mice were injured on the skin by incising the right side of the back for 2 cm in length and 4 mm in depth and then cleaned with 0.9% NaCl solution. To the first group of treatment, the wound was applicated by Amnion, and the second group was applicated by Collagen. Each 4 mice of all group were a termination by ether and encryption on the wounded tissue was conducted on day 3rd, 7th, and 14th. Assessment for a number of fibroblast and collagen synthesis on the wound of back tissue was conducted with the histological examination by painted using hematoxylin-eosin. The results concluded that Collagen application was influencing the mean of fibroblast higher than Amnion, and the lowest was controlled with statistically significant. The mean of collagen used Collagen lower than Amnion, and the lowest was control with statistically significant. It could be concluded that collagen application was preeminent in increasing the productivity of the fibroblast, as well as in developing forms of the collagen synthesis compared with Amnion and control.


2018 ◽  
Vol 34 (08) ◽  
pp. 572-580 ◽  
Author(s):  
Keith Koh ◽  
Terence Goh ◽  
Christopher Song ◽  
Hyun Suh ◽  
Peter Rovito ◽  
...  

Background Of all body regions, lower extremity wounds have been and remain the greatest challenge. Perforator free flaps have been accepted as a reasonable option to solve this dilemma but require the complexity of microsurgery. As a consequence, the possibility that pedicled perforator flaps could supplant even perforator free flaps has recently gained intense enthusiasm. Methods A retrospective investigation was undertaken to compare the validity for the use of perforator flaps of all types at three dissimilar institutions, that is, a university, a regional center, and a community hospital. All flaps performed in the 5-year period, 2011 to 2015, were included to allow at least 1-year follow-up before data analysis. A total of 433 free perforator flaps and 52 pedicled perforator flaps had been performed specifically for the lower extremity. Results Patient demographics, wound etiology, and comorbidities were similar for all institutions. Free flaps were more commonly needed after trauma and for chronic ulcers. Pedicled flaps were more likely an option after tumor excision. Large defects or those involving the foot were better served by free flaps. Overall success for free perforator flaps was 90.1% and for pedicled perforator flaps was 92.3%, with no significant difference noted (p = 0.606) between institutions. Peripheral vascular disease was the only significant comorbidity risk factor for both free and pedicled flap failure. Conclusion Perforator flaps in general have become a reasonable solution for soft tissue defects of the lower extremity. Following careful consideration of the etiology, dimensions, location, patient comorbidities, and presence of adequate perforators, a pedicled or free perforator flap could potentially be successful. Pedicled perforator flaps, if adequate healthy soft tissues remain adjacent to the defect, forecast a continuance of the evolution in seeking simplicity yet reliability by the best flap possible for soft tissue closure of the lower limb wound.


1995 ◽  
Vol 117 (4) ◽  
pp. 409-413 ◽  
Author(s):  
S. N. Robinovitch ◽  
W. C. Hayes ◽  
T. A. McMahon

Recent studies suggest that hip padding systems reduce the incidence of hip fractures during falls. However, no data exist on the force attenuating capacity of hip pads under realistic fall impact conditions, and thus it is difficult to compare the protective merit of various pad designs. Our goal is to design a comfortable hip padding system which reduces femoral impact force in a fall below the mean force required to fracture the elderly cadaveric femur. In pursuit of this objective, we designed and constructed a hip pad testing system consisting of an impact pendulum and surrogate human pelvis. We then developed a hip pad containing a shear-thickening material which allows for shunting of the impact energy away from the femur and into the surrounding soft tissue. Finally, we conducted experiments to assess whether the surrogate pelvis accurately represents the impact behavior of the human female pelvis in a fall, and to determine whether our energy-shunting pad attenuates femoral impact force in a fall more effectively than seven available padding systems. We found the surrogate pelvis accurately represented the human female pelvis in regional variation in soft tissue stiffness, total effective stiffness and damping, and impact force attenuation provided by trochanteric soft tissues. We also found that our padding system attenuated femoral impact force by 65 percent, thereby providing two times the force attenuation of the next best system. Moreover, the energy-shunting pad was the only system capable of lowering femoral impact force well below the mean force required to fracture the elderly femur in a fall loading configuration. These results suggest that the force attenuating potential of hip pads which focus on shunting energy away from the femur is superior to those which rely on absorbing energy in the pad material. While these in-vitro results are encouraging, carefully designed prospective clinical trials will be necessary to determine the efficacy of these approaches to hip fracture prevention.


2018 ◽  
Vol 4 (4) ◽  
pp. 1245-1250 ◽  
Author(s):  
Ahmed AL-Omar ◽  
Usama AL-Dakroroy

The objective of this study was to evaluate the soft tissue changes after anterior maxillary osteotomy using cone beam computed tomography. The study included twelve patients diagnosed as suffering from an excess of the anterior part of maxilla and required surgical correction by anterior maxillary osteotomy. Assessment of Cone beam computed tomography in evaluation the soft tissue changes. All cases subjected to anterior maxillary osteotomy using modified Cuper technique. Follow up of cases was does clinically and radio- graphically by cone beam computed tomography. The results of the study proved that the statistically significant increase in mean Nasolabial angle after 6 months was 5.2 degrees, the mean value of nasal width after 6 months was 0,9mm. The mean value of Philtrum length was 3.3mm. In conclusion, Cone Beam Computed Tomography can be used to obtain dimensionally accurate linear and angular measurement from bony maxillofacial structure and landmarks and allows accurate, three-dimensional imaging of hard and soft tissues.


2020 ◽  
Vol 13 (12) ◽  
pp. e238816
Author(s):  
Igor Ashurko ◽  
Eduard Levonian ◽  
Ilia Dementev ◽  
Svetlana Tarasenko

The application of free connective tissue graft (CTG) is the gold standard in the treatment of gingival recession in the area of teeth and implants. The aim of this case report is to demonstrate a possible mucosal overgrowth complication in the soft tissue grafting area. A 24-year-old patient underwent the treatment of gingival recession in the tooth 2.3 region by an envelope technique using a free CTG from the hard palate region. Seven years after the surgery, a mucosal overgrowth was observed, which developed asymptomatically and did not cause any problems to the patient.


Ultrasound ◽  
2012 ◽  
Vol 20 (2) ◽  
pp. 92-97
Author(s):  
M Bonfield ◽  
F Cramp ◽  
T Robinson

Introduction There is currently little research regarding optimum patient position for venous insufficiency assessment although standing is considered the gold standard in many professional guidelines. Some patients are unable to stand for the examination and scanning patients in a standing position is physically challenging for the sonographer. This pilot study aimed to evaluate the effect of varying patient positioning on the duration of venous reflux. Method Venous reflux duration was measured in symptomatic participants with suspected venous insufficiency. Measurements were taken in the standing position (gold standard) and four alternative positions: 25° reverse-Trendelenburg (RT) tilt, sitting on the edge of the examination couch, 10° RT tilt and 0° RT tilt. The mean reflux duration measured in each different position was compared with the gold standard. Results Complete measurements were obtained from 16 patients (8 men and 8 women). For an incompetent vein, statistical analysis demonstrated a significant difference only between the standing position and the 0° position ( U = 19.0; exact P < 0.01 [2-tailed]). Conclusion Results suggest that several alternative positions could be used for assessing incompetent veins as long as the patient is not lying supine with 0° tilt. This would offer much greater flexibility, which may be of benefit to both patients and sonographers.


Author(s):  
Syed Yusoff Alzawawi Syed Abd Fattah ◽  
Firdaus Hariri ◽  
Phrabhakaran Nambiar ◽  
Zulkiflee Abu Bakar ◽  
Zainal Ariff Abdul Rahman

Objective:To validate the accuracy of the mandibular canal region in 3D biomodel produced by using data obtained from Cone-Beam Computed Tomography (CBCT) of cadaveric mandibles.Methods:Six hemi-mandible samples were scanned using the i-CAT CBCT system. The scanned data was transferred to the OsiriX software for measurement protocol and subsequently into Mimics software to fabricate customized cutting jigs and 3D biomodels based on rapid prototyping technology. The hemi-mandibles were segmented into 5 dentoalveolar blocks using the customized jigs. Digital calliper was used to measure six distances surrounding the mandibular canal on each section. The same distances were measured on the corresponding cross-sectional OsiriX images and the 3D biomodels of each dentoalveolar block.Results:Statistically no significant difference was found when measurements from OsiriX images and 3D biomodels were compared to the “gold standard” -direct digital calliper measurement of the cadaveric dentoalveolar blocks. Moreover, the mean value difference of the various measurements between the different study components was also minimal.Conclusion:Various distances surrounding the mandibular canal from 3D biomodels produced from the CBCT scanned data was similar to that of direct digital calliper measurements of the cadaveric specimens.


2005 ◽  
Vol 42 (4) ◽  
pp. 410-416 ◽  
Author(s):  
Chiarella Sforza ◽  
Claudia Dellavia ◽  
Claudia Dolci ◽  
Elena Donetti ◽  
Virgilio F. Ferrario

Objective To supply quantitative information about the facial soft tissues of subjects with Down syndrome by using summary anthropometric measurements. Design, Setting, and Patients The three-dimensional coordinates of soft tissue facial landmarks were obtained using a computerized digitizer in 28 subjects with Down syndrome (11 girls and women and 17 boys and men aged 12 to 45 years) and 429 healthy controls matched for sex, age, and ethnicity. From the landmarks, 18 facial dimensions were calculated. Data were compared with those collected in healthy individuals by computing z-scores. Two summary anthropometric measurements for quantifying craniofacial variations were assessed in both the subjects with Down syndrome and the reference subjects: the mean z-score (an index of overall facial size) and its standard deviation, craniofacial variability index (an index of facial harmony). Results In subjects with Down syndrome, facial size was smaller than in normal individuals, and in 17 subjects the mean z-score fell outside the normal interval (mean ± 2 SD). Twenty subjects had a craniofacial variability index larger than the normal interval. Conclusions The facial soft tissue structures of subjects with Down syndrome differed from those of normal controls of the same age, sex, and ethnic group: a reduced facial size was coupled with a global anomalous relationship between individual measurements. The two indices allowed discriminating more than 89% of subjects with Down syndrome when compared with normal subjects.


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