Delayed chance fracture pattern injury in a case of skeletal fluorosis

The results of studying operational destruction of a high-loaded cardan shaft of the propeller engine made of steel 38KhN3MFA are presented to elucidate the cause of damage and develop a set of recommendations and measures aimed at elimination of adverse factors. Methods of scanning electron and optical microscopy, as well as X-ray spectral microanalysis are used to determine the mechanical properties, chemical composition, microstructure, and fracture pattern of cardan shaft fragments. It is shown that the mechanical properties and chemical composition of the material correspond to the requirements of the regulatory documentation, defects of metallurgical origin both in the shaft metal and in the fractures are absent. The microstructure of the studied shaft fragments is tempered martensite. Fractographic analysis revealed that the destruction of cardan shaft occurred by a static mechanism. The fracture surface is coated with corrosion products. The revealed cracks developed by the mechanism of corrosion cracking due to violation of the protective coating on the shaft. The results of the study showed that the destruction of the cardan shaft of a propeller engine made of steel 38Kh3MFA occurred due to formation and development of spiral cracks by the mechanism of stress corrosion cracking under loads below the yield point of steel. The reason for «neck» formation upon destruction of the shaft fragment is attributed to the yield point of steel attained during operation. Regular preventive inspections are recommended to assess the safety of the protective coating on the shaft surface to exclude formation and development of corrosion cracks.

Download Full-text

Load-Bearing Capacity of Direct Inlay-Retained Fibre-reinforced Composite Fixed Partial Dentures with Different Cross-Sectional Pontic Design

Revista de Chimie ◽

10.37358/rc.17.1.5397 ◽

2017 ◽

Vol 68 (1) ◽

pp. 94-100

Author(s):

Oana Tanculescu ◽

Adrian Doloca ◽

Raluca Maria Vieriu ◽

Florentina Mocanu ◽

Gabriela Ifteni ◽

...

Keyword(s):

Bearing Capacity ◽

Fracture Pattern ◽

Load Bearing Capacity ◽

Cross Sectional ◽

Load Bearing ◽

Reinforced Composite ◽

Polyethylene Fibre

The load-bearing capacity and fracture pattern of direct inlay-retained FRC FDPs with two different cross-sectional designs of the ponticwere tested. The aim of the study was to evaluate a new fibre disposition. Two types of composites, Filtek Bulk Fill Posterior Restorative and Filtek Z250 (3M/ESPE, St. Paul, MN, USA), and one braided polyethylene fibre, Construct (Kerr, USA) were used. The results of the study suggested that the new tested disposition of the fibres prevented in some extend the delamination of the composite on buccal and facial sides of the pontic and increased the load-bearing capacity of the bridges.

Download Full-text

Chance Fracture of the Upper Thoracic Spine

American Journal of Roentgenology ◽

10.2214/ajr.185.2.01850555 ◽

2005 ◽

Vol 185 (2) ◽

pp. 555-555 ◽

Cited By ~ 1

Author(s):

Richard H. Daffner

Keyword(s):

Thoracic Spine ◽

Upper Thoracic Spine ◽

Chance Fracture ◽

Upper Thoracic

Download Full-text

The Influence of Force Direction on the Fracture Pattern and Fracture Resistance of Canine Teeth in Dogs

Journal of Veterinary Dentistry ◽

10.1177/0898756417705229 ◽

2017 ◽

Vol 34 (1) ◽

pp. 8-17 ◽

Cited By ~ 2

Author(s):

Stephanie Goldschmidt ◽

Catherine Zimmerman ◽

Caitlyn Collins ◽

Scott Hetzel ◽

Heidi-Lynn Ploeg ◽

...

Keyword(s):

Fracture Resistance ◽

Ex Vivo ◽

Testing Machine ◽

Fracture Pattern ◽

Hard Tissue ◽

Canine Tooth ◽

Cross Sectional ◽

Significant Difference ◽

Force Direction ◽

Testing Group

Biomechanical studies of the elongated canine tooth of animals are few, and thus our understanding of mechanical and physical properties of animal teeth is limited. The objective of the present study was to evaluate the influence of force direction on fracture resistance and fracture pattern of canine teeth in an ex vivo dog cadaver model. Forty-five extracted canine teeth from laboratory beagle dogs were standardized by hard tissue volume and randomly distributed among 3 force direction groups. The teeth were secured within a universal testing machine and a load was applied at different directions based on testing group. The maximum force to fracture and the fracture pattern classification were recorded for each tooth. After correcting for hard tissue cross-sectional area in a multivariate analysis, no significant difference in the amount of force required for fracture was apparent between the different force direction groups. However, the influence of force direction on fracture pattern was significant. The results of this study may allow the clinician to educate clients on possible causal force directions in clinically fractured teeth and, thus, help prevent any contributing behavior in the future.

Download Full-text

Fracture Load of Metal, Zirconia and Polyetheretherketone Posterior CAD-CAM Milled Fixed Partial Denture Frameworks

Materials ◽

10.3390/ma14040959 ◽

2021 ◽

Vol 14 (4) ◽

pp. 959

Author(s):

Verónica Rodríguez ◽

Celia Tobar ◽

Carlos López-Suárez ◽

Jesús Peláez ◽

María J. Suárez

Keyword(s):

Computer Aided Design ◽

Testing Machine ◽

Fracture Load ◽

Fracture Pattern ◽

Bending Test ◽

Weibull Statistics ◽

Promising Alternative ◽

Computer Aided ◽

Cad Cam ◽

Group 2

The aim of this study was to investigate the load to fracture and fracture pattern of prosthetic frameworks for tooth-supported fixed partial dentures (FPDs) fabricated with different subtractive computer-aided design and computer-aided manufacturing (CAD-CAM) materials. Materials and Methods: Thirty standardized specimens with two abutments were fabricated to receive three-unit posterior FDP frameworks with an intermediate pontic. Specimens were randomly divided into three groups (n = 10 each) according to the material: group 1 (MM)—milled metal; group 2 (L)—zirconia; and group 3 (P)—Polyetheretherketone (PEEK). The specimens were thermo-cycled and subjected to a three-point bending test until fracture using a universal testing machine (cross-head speed: 1 mm/min). Axial compressive loads were applied at the central fossa of the pontics. Data analysis was made using one-way analysis of variance, Tamhane post hoc test, and Weibull statistics (α = 0.05). Results: Significant differences were observed among the groups for the fracture load (p < 0.0001). MM frameworks showed the highest fracture load values. The PEEK group registered higher fracture load values than zirconia samples. The Weibull statistics corroborated these results. The fracture pattern was different among the groups. Conclusions: Milled metal provided the highest fracture load values, followed by PEEK, and zirconia. However, all tested groups demonstrated clinically acceptable fracture load values higher than 1000 N. PEEK might be considered a promising alternative for posterior FPDs.

Download Full-text

Application of Pelvic Circumferential Compression Devices in Pelvic Ring Fractures—Are Guidelines Followed in Daily Practice?

Journal of Clinical Medicine ◽

10.3390/jcm10061297 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1297

Author(s):

Valerie Kuner ◽

Nicole van Veelen ◽

Stephanie Studer ◽

Bryan Van de Wall ◽

Jürgen Fornaro ◽

...

Keyword(s):

Clinical Education ◽

Trauma Center ◽

Pelvic Ring ◽

Daily Practice ◽

Pelvic Trauma ◽

Fracture Pattern ◽

Pelvic Fractures ◽

Unstable Fracture ◽

Associated Injuries ◽

Resuscitation Room

Early administration of a pelvic circumferential compression device (PCCD) is recommended for suspected pelvic trauma. This study was conducted to evaluate the prevalence of PCCD in patients with pelvic fractures assigned to the resuscitation room (RR) of a Level I trauma center. Furthermore, correct application of the PCCD as well as associated injuries with potential clinical sequelae were assessed. All patients with pelvic fractures assigned to the RR of a level one trauma center between 2016 and 2017 were evaluated retrospectively. Presence and position of the PCCD on the initial trauma scan were assessed and rated. Associated injuries with potential adverse effects on clinical outcome were analysed. Seventy-seven patients were included, of which 26 (34%) had a PCCD in place. Eighteen (23%) patients had an unstable fracture pattern of whom ten (56%) had received a PCCD. The PCCD was correctly placed in four (15%) cases, acceptable in 12 (46%) and incorrectly in ten (39%). Of all patients with pelvic fractures (n = 77, 100%) treated in the RR, only one third (n = 26, 34%) had a PCCD. In addition, 39% of PCCDs were positioned incorrectly. Of the patients with unstable pelvic fractures (n = 18, 100%), more than half either did not receive any PCCD (n = 8, 44%) or had one which was inadequately positioned (n = 2, 11 %). These results underline that preclinical and clinical education programs on PCCD indication and application should be critically reassessed.

Download Full-text

Should the location of distal tibial plating be influenced by the varus or valgus fracture pattern of tibial pilon fracture?

Archives of Orthopaedic and Trauma Surgery ◽

10.1007/s00402-021-03901-4 ◽

2021 ◽

Author(s):

Choon Chiet Hong ◽

Soura Saha ◽

Si Heng Sharon Tan ◽

Ken Jin Tan ◽

Diarmuid Paul Murphy ◽

...

Keyword(s):

Fracture Pattern ◽

Pilon Fracture ◽

Tibial Pilon ◽

Tibial Pilon Fracture

Download Full-text

Fracture System and Rock-Mass Characterization by Borehole Camera Surveying: Application in Dimension Stone Investigations in Geologically Complex Structures

Applied Sciences ◽

10.3390/app11020764 ◽

2021 ◽

Vol 11 (2) ◽

pp. 764

Author(s):

Ivica Pavičić ◽

Ivo Galić ◽

Mišo Kucelj ◽

Ivan Dragičević

Keyword(s):

Rock Mass ◽

Fractured Rock ◽

Low Cost ◽

Fracture Pattern ◽

Dimension Stone ◽

Rock Mass Characterization ◽

Size And Shape ◽

Distribution Parameters ◽

Borehole Camera ◽

Fracture Distribution

The successful exploration of dimension stone mainly depends on the quality, size, and shape of extractable blocks of dimension stone. The investigated area is in the Pelješac Peninsula (Croatia), in the External Dinarides orogeny, built from thick carbonate succession, characterized by relatively small deposits of high-quality dimension stone. These conditions demand challenging geological investigations in the “pre-quarry” phase to find optimal quarry location. The size and shape of dimension stone blocks are mainly controlled by fracture pattern systems. In the rugged, covered terrains, it is very hard to obtain a satisfactory amount of fracture data from the surface, so it is necessary to collect them from the underground. Borehole camera technology can visualize the inner part of the rock mass and measure the fracture characteristics. The main conclusions are as follows: (1) the digital borehole camera technology provides a quick, effective, and low-cost geological survey of fractured rock mass; (2) statistical fracture distribution parameters, P10, fracture spacing, Volumetric Joint Count (Jv) based on borehole wall survey can reflect the integrity of rock mass, providing a solid decision-making base for further investment plans and dimension stone excavation method.

Download Full-text

Complications of Frontal Sinus Fractures

Craniomaxillofacial Trauma & Reconstruction ◽

10.1055/s-0029-1202597 ◽

2009 ◽

Vol 2 (1) ◽

pp. 27-34 ◽

Cited By ~ 13

Author(s):

Stephen E. Metzinger ◽

Rebecca C. Metzinger

Keyword(s):

Frontal Sinus ◽

Fracture Pattern ◽

Medical Attention ◽

Associated Injuries ◽

Soft Tissue Envelope ◽

Patient Gender ◽

Maxillofacial Fractures ◽

Long Term Follow Up ◽

Frontal Sinus Fracture ◽

The One

Frontal sinus fracture represents 5 to 12% of all maxillofacial fractures. Because of the anatomic position of the frontal sinus and the enormous amount of force required to create a fracture in this area, these injuries are often devastating and associated with other trauma. Associated injuries include skull base, intracranial, ophthalmologic, and maxillofacial. Complications should be categorized to address these four areas as well as the skin—soft tissue envelope, muscle, and bone. Other variables that should be examined are age of the patient, gender, mechanism of injury, fracture pattern, method of repair, and associated injuries. Management of frontal sinus fractures is so controversial that the indications, timing, method of repair, and surveillance remain disputable among several surgical specialties. The one universal truth that is agreed upon is that all patients undergoing reconstructive surgery of the frontal sinus have a lifelong risk for delayed complications. It is hoped that when patients do experience the first symptoms of a complication, they seek immediate medical attention and avoid potentially life-threatening situations and the need for crippling or disfiguring surgery. The best way to facilitate this is through long-term follow-up and routine surveillance.

Download Full-text