scholarly journals Three-dimensionally preserved soft tissues and calcareous hexactins in a Silurian sponge: implications for early sponge evolution

2019 ◽  
Vol 6 (7) ◽  
pp. 190911 ◽  
Author(s):  
Ardianty Nadhira ◽  
Mark D. Sutton ◽  
Joseph P. Botting ◽  
Lucy A. Muir ◽  
Pierre Gueriau ◽  
...  

Sponges (Porifera), as one of the earliest-branching animal phyla, are crucial for understanding early metazoan phylogeny. Recent studies of Lower Palaeozoic sponges have revealed a variety of character states and combinations unknown in extant taxa, challenging our views of early sponge morphology. The Herefordshire Konservat–Lagerstätte yields an abundant, diverse sponge fauna with three-dimensional preservation of spicules and soft tissue. Carduispongia pedicula gen. et sp. nov. possesses a single layer of hexactine spicules arranged in a regular orthogonal network. This spicule type and arrangement is characteristic of the reticulosans, which have traditionally been interpreted as early members of the extant siliceous Class Hexactinellida. However, the unusual preservation of the spicules of C . pedicula reveals an originally calcareous composition, which would be diagnostic of the living Class Calcarea. The soft tissue architecture closely resembles the complex sylleibid or leuconid structure seen in some modern calcareans and homoscleromorphs. This combination of features strongly supports a skeletal continuum between primitive calcareans and hexactinellid siliceans, indicating that the last common ancestor of Porifera was a spiculate, solitary, vasiform animal with a thin skeletal wall.

2020 ◽  
Vol 54 (4) ◽  
pp. 289-296
Author(s):  
Adeeba Ali ◽  
Anil K. Chandna ◽  
Anshul Munjal

Background: Concerns about the accuracy and reliability of soft tissue landmarks using two-dimensional (2D) and three-dimensional (3D) imaging. Objective: The aim of the systematic review is to estimate accuracy and reliability of soft tissue landmarks with 2D imaging and 3D imaging for orthodontic diagnosis planning and treatment planning purposes. Data Sources: Electronic database search was performed in MEDLINE via PubMed, Embase via embase.com, and the Cochrane library website. Selection Criteria: The data were extracted according to two protocols based on Centre for Evidence-Based Medicine (CEBM) critical appraisal tools. Next, levels of evidence were categorized into three groups: low, medium, and high. Data Synthesis: Fifty-five publications were found through database search strategies. A total of nine publications were included in this review. Conclusion According to the available literature, 3D imaging modalities were more accurate and reliable as compared to 2D modalities. Cone beam computed tomography (CBCT) was considered the most reliable imaging tool for soft tissues.


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.


Author(s):  
Jorge A. Vergen ◽  
Tinen L. Iles ◽  
Paul A. Iaizzo

Abstract Mimetic three-dimensional (3D) printing has been shown to enhance presurgical planning and improve patient outcomes. However, data inconsistencies and non-optimized soft tissue data management strategies have impaired efforts to characterize soft tissues and translate biophysical values to 3D printing media durometers and shore values. As a result, finished models are inconsistent and exhibit reduced mimetic qualities. Improving biophysical characterizations of soft tissues, analysis strategies, and consolidation infrastructures are important factors that will improve 3D modeling in a presurgical planning setting. In our ongoing associated studies, both physiologically viable and formalin fixed large mammalian tissues (including human) were assessed using uniaxial and biaxial testing strategies. Biophysical datasets were analyzed using a gated analysis strategy, tailored to data acquisition methods developed within the University of Minnesota Visible Heart® Labs (VHL). A SQL database was then constructed to consolidate analyzed data for future retrieval. This strong preliminary data is a foundation for further development and refinement of future studies. It is our long-term goal that these strategies be improved and adopted to enhance the mimetic qualities of 3D presurgical planning models.


2018 ◽  
Vol 12 (1) ◽  
pp. 366-376
Author(s):  
Rahul Tiwari ◽  
P. Srinivas Chakravarthi ◽  
Vivekanand S. Kattimani ◽  
Krishna Prasad Lingamaneni

Background: Facial appearance is an important factor, affects social and psychological well-being. The ideal positioning of jaws and soft tissues is crucial during orthognathic surgery for a better outcome, but the response of facial soft tissues does not always reflect the exact movements of the underlying jaws in 1:1 ratio. So, soft tissue changes following orthognathic surgery require utmost attention during surgical correction to make successful treatment. Aims and Objectives: Evaluation of perioral soft tissue changes after orthognathic surgical procedures. The objectives of the study were to assess and compare pre and post-operative perioral soft tissue changes of lip width, nasolabial and mentolabial angle using Three Dimensional Computed Tomography scan (3DCT). Patient and Methods: The study involved ten patients for evaluation requiring orthognathic surgical procedures (maxillary or mandibular anteroposterior excess or deficiency, transverse deformities, vertical maxillary excess and facial asymmetry) presented to the department of oral and maxillofacial surgery during 2014-2016. Pre and post-operative 3DCT scan were taken after 12 months using iCT 256 slice whole body CT scanner and evaluated for changes using Dicom PMS D view. Results: Significant changes were observed in nasolabial angle after maxillary advancement (1.81°) and maxillary setback procedure (2.73°). The mentolabial angle was significantly increased with mandibular setback procedures (3.27°). Mandibular advancement procedures showed both increase (3.6°) and decrease (7.6°) in mentolabial angle. Conclusion: 3DCT showed a significant difference in perioral soft tissue changes in nasolabial and mentolabial angle but no significant change was observed in lip width. 3DCT is a reliable tool for 3D assessment. The conventional thought of changes in Nasolabial angle after surgery is changing due to the underlying factors which should be considered for prediction.


1997 ◽  
Vol 34 (1) ◽  
pp. 52-57 ◽  
Author(s):  
Andrew M. Mccance ◽  
James P. Moss ◽  
W. Rick Fright ◽  
Alf D. Linney

A new color-coded method of illustrating three-dimensional changes in the bone and the ratio of soft tissue to bone movement is described. The technique is illustrated by superimposing preoperative and 1-year postoperative CT scans of three patients following bimaxillary surgery. The method has proved to be a very simple, effective, and readily interpreted method of quantifying both bone and the ratio of movement of the overlying soft tissues across the face following surgery.


2013 ◽  
Vol 84 (1) ◽  
pp. 38-47 ◽  
Author(s):  
Jae-Kyu Lee ◽  
Pil-Kyo Jung ◽  
Cheol-Hyun Moon

ABSTRACT Objective: To investigate discrepancies in results of facial asymmetry analysis using different cone beam computed tomography (CBCT) image reorientation methods and the effectiveness of soft tissue as a reorientation reference for analysis of facial asymmetry. Materials and Methods: An asymmetric group of 30 patients with 4 mm or more of chin point (menton [Me]) deviation and a symmetric group of 30 patients with less than 4 mm of deviation of Me were chosen as study subjects. Three orientation methods were used to calculate and compare Me deviation values of the 60 subjects. Two methods used only skeletal landmarks for reference, and one method included the soft tissue landmarks around the eye. Preferences of an expert group for the facial midline as determined by each reorientation method were also examined. Results: The examinations showed significant discrepancies in Me deviation values between the three reorientation methods. The expert group showed the greatest preference for the facial midline reorientation method that incorporated soft tissue landmarks of the eye. Conclusions: These study findings suggest that the inclusion of soft tissue landmarks, especially those around the eyes, is effective for three-dimensional CBCT image reorientation for facial asymmetry analysis.


2009 ◽  
Vol 124 (5) ◽  
pp. 564-568 ◽  
Author(s):  
M Suzuki ◽  
Y Ogawa ◽  
T Hasegawa ◽  
S Kawaguchi ◽  
K Yukawa ◽  
...  

AbstractAim:To examine the usefulness of a three-dimensional model for surgical navigation of cholesteatoma.Materials and method:A three-dimensional model was prototyped using selective laser sintering. Based on detailed computed tomography data, powder layers were laser-fused and accumulated to create a three-dimensional structure. The computed tomography threshold was adjusted to simultaneously replicate bony structures and soft tissues.Results:The cholesteatoma, major vessels and bony structures were well replicated. This laser-sintered model was used to aid surgery for recurrent cholesteatoma. The cholesteatoma, which extended from the hypotympanum through the styloid process sheath and the internal carotid artery sheath, was removed safely via a minimal skin incision.Conclusion:The laser-sintered model was useful for surgical planning and navigation in a cholesteatoma case involving complex bony structures and soft tissue.


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.


SLEEP ◽  
2020 ◽  
Vol 43 (Supplement_1) ◽  
pp. A401-A402
Author(s):  
N Ihemeremadu ◽  
N Lavi-Romer ◽  
Y Zang ◽  
B Keenan ◽  
R Schwab

Abstract Introduction Studies show that OSA is linked to impaired glucose tolerance, insulin resistance, and the onset of diabetes. We hypothesized that diabetic OSA patients will have higher apnea-hypopnea index (AHI) values than OSA patients without diabetes after adjusting for age and body mass index (BMI) and that this difference can be explained through increases in upper airway structures between diabetic and non-diabetic OSA patients. Methods This study evaluated differences in upper airway and craniofacial dimensions and volume of the pharyngeal soft tissues between diabetic and non-diabetic patients with obstructive sleep apnea (OSA) using magnetic resonance imaging (MRI). Airway sizes, soft tissue volumes and craniofacial dimensions were quantified using three-dimensional MRI in OSA patients without diabetes (n=237) and OSA patients with diabetes (n=64). Comparisons in upper airway measures among diabetics and non-diabetics were performed using linear regression models controlling for age, sex, BMI, race, and AHI. Results Among study participants, diabetic OSA patients were older than non-diabetic OSA patients (54.2±10.1 vs. 47.3±11.1 years; p<0.0001). No significant differences were found between diabetic and non-diabetic OSA patients with respect to BMI (39.8±7.0 vs. 38.4±8.8 kg/m2; p=0.207) or AHI (45.0±31.0 vs. 38.8±27.8 events/hour; p=0.154). In covariate adjusted models, non-diabetic OSA patients also had smaller RP minimum airway area (adjusted difference [95% CI] = -3119 [-5359, 879] mm2; p=0.0066) and RP minimum AP distance (-16.0 mm [-29.6, -2.5]; p=0.021) compared to diabetic OSA patients. No differences were observed in soft tissue volumes or craniofacial dimensions. Conclusion While diabetics had higher average AHI, we observed no significant differences in AHI between diabetic and non-diabetic patients with sleep apnea. In general, upper airway anatomy was similar between diabetic and non-diabetics apneics, controlling for demographic factors and AHI. Future studies should examine dynamic changes, in addition to static upper airway anatomy, in diabetic and non-diabetics apneics. Support  


2021 ◽  
Vol 19 (4) ◽  
pp. 317-319
Author(s):  
A. B. Adzhieva ◽  
I. A. Voronov ◽  
S. S. Ivanov ◽  
H. M. Nalchajyan

Lack of adequate width and thickness of periodontal or peri-implant soft tissues can compromise the aesthetics, function or survival of teeth and dental implants. Biomaterials are widely used in dentistry to overcome the disadvantages of autogenous tissue transplantation. The advantage of using biomaterials is that there is no need for re-surgery and that they are available in large quantities. The most widely used biomaterial for soft tissue augmentation is collagen, as it is believed to best mimic the natural cellular environment of the extracellular matrix, although other biomaterials are also candidates for soft tissue regeneration. Collagen matrices differ in composition, three-dimensional structure, elasticity and mechanical stability. Aim. is to review the literature on the optimization of regeneration at the stages of soft tissue augmentation using a collagen matrix.


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