Complete Specimens Research Articles

An ontogenetic study of Eospirigerina putilla (Brachiopoda) surviving the Late Ordovician mass extinction

The ontogeny of the brachiopod can be reflected by the shell outline, size, and their interconnections. As a representative early atrypid brachiopod group of the Edgewood-Cathay Fauna, the genus Eospirigerina survived the Late Ordovician mass extinction (LOME). Abundant E. putilla specimens were collected from the “Wulipo Bed” limestone (upper Hirnantian, Ordovician). As a typical Eospirigerina dominated Edgewood-Cathay Fauna from the upper Hirnantian (Ordovician) of northeastern Yunnan, China, the quantitative ontogenetic study of E. putilla can provide a better understanding of its palaeoecology. Using the image contour recognition, we develop an automated measuring tool, test its robustness, and measure 554 complete and silicified specimens of E. putilla. An abnormal palaeoenvironment that the E. putilla population inhabited in is suggested by the high mortality of small individuals indicated by the size-frequency histogram and survivorship curve. Using quadratic polynomial regression, the negative allometric pattern of the shell length to width in the population is recognized. Using geometric morphometrics with semi-landmarks for 51 specimens from the population, the ontogenic trends are mapped by PCA with thin-plate splines, in which the heterochronic shifts may occur from an elongate shell with relatively larger ventral cardinal area and delthyrium to wider outline and smaller beak. Such heterochronic development is possibly caused by the unstable and stressful environment immediately after the LOME.

Mammoth Fauna Remains From Late Pleistocene Deposits of the Dmitry Laptev Strait South Coast (Northern Yakutia, Russia)

The Yedoma Ice Complex in northern Yakutia provides perfect preservation conditions for frozen remains of vertebrate animals. Even complete mummified specimens of the late Pleistocene Beringian Mammoth fauna such as woolly mammoth, woolly rhinoceros, horse, and bison are occasionally found in permafrost deposits across eastern Siberia, i.e., in West Beringia, although bones are much more commonly found. The present study characterizes mammal bones from late Pleistocene and Holocene permafrost deposits exposed on the Oyogos Yar coast, part of the southern shore of the Dmitry Laptev Strait that connects the Laptev and East Siberian seas. The study applies a method to characterize fossil bone samples by the location of their discovery and by the accuracy of their relation to a depositional horizon. We analyzed a total of 38 finite radiocarbon ages of bone material from mammoth, horse, and musk ox, spanning from about 48.8 to 4.5 ka BP and including both our own data and data from the literature, in addition to previous publications that reported numerous bones with infinite ages from the Oyogos Yar coast. The distribution of bones and tooth along the coastal permafrost exposure is not uniform; it depends upon whether the material was found in situ, on thermo-terraces, or on the shore. The overall bone collection consists of 13 species of which Mammuthus primigenius (woolly mammoth, 41%), Bison priscus (bison, 19%), Equus ex gr., caballus (horse, 19%), and Rangifer tarandus (reindeer, 16%) predominate. The fossil bone species distribution is similar to those of other prominent Yedoma outcrops in the region, i.e., on Bykovsky Peninsula and on Bol’shoy Lyakhovsky Island. Correlation analysis shows that the Oyogos Yar bone sampling sites of different geomorphological settings are similar to each other but not to all sampling sites within the other two locations on Bykovsky Peninsula and on Bol’shoy Lykahovsky Island. High similarities in terms of correlation coefficients between specific sampling sites are often not represented in the cluster analysis.

An unexpected new red-bellied Stumpffia (Microhylidae) from forest fragments in central Madagascar highlights remaining cryptic diversity.

The Madagascan endemic subfamily Cophylinae in the family Microhylidae, is an example of a taxonomic group for which much is still to be discovered. Indeed, the cophyline frogs present a large portion of Madagascar's cryptic and microendemic amphibian diversity, yet they remain understudied. A new red-bellied species of the microhylid frog genus Stumpffia is described from the central plateau of Madagascar. Visual encounter surveys in Ambohitantely and Anjozorobe in 2019 and 2020 identified this previously unknown Stumpffia species, which closely resembles Stumpffiakibomena known from Andasibe in the east. Stumpffialynnae sp. nov. adds another species to the red-bellied species complex, differing from S.kibomena by genetic differentiation in the mitochondrial 16S rRNA gene (3.6-3.9%) and distinct nuclear RAG1 haplotypes, as well as strongly by its advertisement call. The new species is known from across Ambohitantely Special Reserve and Anjozorobe Angavo protected area, but is known only from one complete specimen and eight individual tissue samples. Based on the rarity of the species, the small number of locations in which it has been found, and its disappearing forest habitat, its IUCN Red List classification is suggested as "Endangered". This species is the first Stumpffia described from Madagascar's central plateau, highlighting the importance of conserving the remnant forest fragments in this area and the ongoing need to survey and protect this threatened habitat type.

Cadaveric study of anatomical measurement of isthmus parameters of lumbar spine to guide cortical bone screw placement.

SUMMARYOBJECTIVE:To reduce surgical exposure and improve accuracy, this study evaluated the anatomical distance parameter D (including D1, D2, and D3) of the lumbar isthmus for cortical bone screw insertion.METHODS:A total of 25 structurally complete lumbar dry specimens were used for lumbar anatomy measurements. The six cadaver specimens were divided into upper and lower parts on the plane of the T11–T12 vertebrae, and we use the lower parts. Therefore, six lumbar wet specimens and another four complete lumbar dry specimens were selected. The lumbar isthmus tangent point was considered a coordinate origin, and the insertion point was determined through translating the distance of D1 value to the midline of the vertebral body horizontally and then vertically moved toward inferior board of the transverse process with the distance of D3 value.RESULTS:In four dry and six wet intact lumbar specimens, cortical bone screws were placed according to the average value of the isthmus parameter D. A total of 100 trajectories were verified in specimens by X-ray and computed topography scan to evaluate the safety, accuracy, and feasibility of the surgical use of isthmus parameter D. Using this parameter, the rates of excellent screw placement were 95% (38/40) in four dry specimens and 88.7% (53/60) in six wet specimens.CONCLUSION:The isthmus parameter D is easier to use by the operator, which can improve surgical accuracy and reduce operation time.LEVEL OF EVIDENCE:Level IV, prospective study.

Distal Femoral Replacement as a Salvage Treatment After Desmoplastic Fibroma Resection

Desmoplastic fibroma is an extremely rare primary bone tumor that can mimic the presentation of other bone lesions. We describe the case of a middle-aged male with a mass on the left distal femur initially diagnosed as fibrous dysplasia that underwent a wide margin excision followed by a distal femoral replacement to restore anatomy and functionality. Histologic examination of the complete surgical specimen was consistent with a desmoplastic fibroma. This case is the first report of a successful application of endoprosthetic reconstruction after desmoplastic fibroma resection.

Two new pendulous epiphytic Columnea L. (Gesneriaceae) species from the Chocó forests of the Northern Andes.

Exploratory field expeditions to the Chocó forests in the northwestern slopes of the Ecuadorian and Colombian Andes resulted in the discovery of two new species of Columnea (Gesneriaceae). Columneafluidifolia J.L.Clark & F.Tobar, sp. nov., is described as a narrow endemic from Bosque Protector Mashpi and surrounding areas in the province of Pichincha in northern Ecuador. Columneapendens F.Tobar, J.L.Clark & J.F.Sm., sp. nov., is described from recently discovered populations in the provinces of Carchi and Santo Domingo de los Tsáchilas (Ecuador) and the departments of Cauca and Nariño in southwestern Colombia. The two new species are pendent epiphytes with elongate shoots and shallowly bilabiate to nearly tubular corollas. Descriptions, complete specimen citations, and a distribution map are provided. Based on IUCN guidelines, a preliminary conservation status of Critically Endangered (CR) is provided for C.fluidifolia and Endangered (EN) is provided for C.pendens.

The oldest Euphasmatodea (Insecta, Phasmatodea): modern morphology in an Early Cretaceous stick insect fossil from the Crato Formation of Brazil

AbstractStick insects (Phasmatodea) are herbivorous, mostly nocturnal insects known for their camouflage specialization, constituting a moderately diverse group with around 3400 extant described species. The overall poor and often confusing fossil record of Phasmatodea, especially regarding older taxa, has muddled the knowledge of the early evolution of the lineage and hindered reliable calibration points for ordinal‐level phylogenies. The phylogenetic relationships within the order remain unresolved, but recent research sheds more light on the subject. Here we report on the oldest known fossil of Euphasmatodea, by revising the taxonomic identity of one fossil species (Eoproscopia reliquum Mendes, Vasconcelos & Oliveira) previously described as a stick grasshopper (family Proscopiidae). Based on the finding of a more complete specimen the taxon is redescribed and a new genus, Araripephasma, is erected to accommodate this species in Euphasmatodea. Araripephasma reliquum comb. nov. is a remarkably modern‐looking stick insect species that provides a new minimum age for Euphasmatodea and sets a good and reliable calibration point for phylogenetic and evolutionary studies. The implications of this rare finding for the evolutionary history of Phasmatodea are discussed.

Nondestructive evaluation of carbon-fiber composites using digital image correlation, acoustic emission, and optical based modal analysis

Composite materials are increasingly used in the wind industries. Damage detection and health monitoring of composite materials are challenging due to the complex internal structure and unique material properties. Digital image correlation (DIC) and acoustic emission (AE) are both used for damage detection in structures. In this work, DIC performs a full-field strain measurement on the surface of the carbon-fiber specimen while AE continuously monitors and records the AE signals generated from specimen subsurface structure failures. These health monitoring techniques are integrated and evaluated in this study to correlate surface strain measurements and acoustic emission measurements on carbon-fiber specimens. The AE measurement results show that there is a correlation between the occurrence of AE events and the timing of complete specimen failure. DIC with a high-speed stereo camera system is also adopted to extract the change in the resonance frequencies and displacement and strain mode shapes of the specimen during experiments in cyclic loading.

Influence of the Number of Parallel Joints on the Dynamic Mechanical Properties of Rock-Like Features

The number and distribution of joints in rock are closely related to their physical and mechanical properties. In this paper, given the propagation law of explosive stress waves in jointed rock during rock blasting and the influence of joints on dynamic mechanical properties and crushing energy dissipation of rock, parallel joints are simulated in the construction of concrete specimens using a mica sheet. The discrete Hopkinson test device is used to perform the impact test, which is based on the three-wave and fractal theory. Under dynamic load, the fluctuation characteristics, failure mode, fractal dimension, and energy dissipation transfer law of rock-like specimens with various parallel joints are studied in detail. The results show that the overall failure of the specimen becomes more severe with the increase of parallel joints, and the failure mode is changed from the conjugate shear failure of the complete specimen to the edge collapse failure with joints. Thus, as the number of joints increases, the static strength decreases, and the degree of reduction is positively related to the number of joints. With the number of joints, the changing trend of enhancement factor increases first and then slows down. Compared with nonjointed specimens, the transmission coefficient of 1-3 jointed specimens is decreased by 0.22, 0.05, and 0.17, respectively. The dimension of the specimen D f is positively correlated. Under the synonymous impact pressure of 0.35 MPa, the corresponding fractal dimension is increased from 2.27 to 2.42. The crushing energy consumption density, transmission coefficient, and dynamic compressive strength σ d of the specimen are significantly negatively correlated, and the crushing energy consumption density of the specimen decreased from 0.82 J/cm3 to 0.28 J/cm3.

The soft tissue and skeletal anatomy of two Late Jurassic ichthyosaur specimens from the Solnhofen archipelago.

Ichthyosaurs from the Solnhofen Lagerstätte are among the only examples of soft tissue preservation in the major Middle Jurassic–middle Cretaceous family Ophthalmosauridae. However, few such specimens are currently described, and the taphonomical pathways for the preservation of soft tissue are not well understood. In order to answer this, two new ichthyosaur specimens, one nearly complete and one isolated tail, are described here. The nearly complete specimen is assigned to Aegirosaurus sp. It is accompanied by large amounts of incrustation pseudomorphs (epimorphs) of soft tissue preserved as apatite. It also preserves a nearly complete gastral basket, for the first time in ophthalmosaurids. Soft tissue samples were analyzed using X-ray diffraction (XRD) and scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS) analysis. The analyses confirm the presence of apatite, with phosphate most likely derived from the body itself.

68Ga]Ga-PSMA-11 PET/CT has potential application in predicting tumor HIF-2α expression and therapeutic response to HIF-2α antagonists in patients with RCC.

To evaluate the efficacy of parameters derived from [68Ga]Ga-PSMA-11 PET/CT images in predicting pathological HIF-2α expression in primary tumors among patients with renal cell carcinoma (RCC). Fifty-three RCC patients with preoperative [68Ga]Ga-PSMA-11 PET/CT scans and complete surgical specimens were retrospectively enrolled in this study. Radiographic parameters were obtained from PET/CT images, and immunohistochemistry was used to measure the expression of HIF-2α and PSMA. Continuous variables and categorical variables were analyzed by the Mann-Whitney U test and chi-square test, respectively. ROC analysis was used to test the efficacy of several preoperative parameters in identifying pathological HIF-2α expression. Univariable logistic regression analyses were performed for significant parameters to predict pathological HIF-2α expression in RCC. Of the 53 tumors, 29 (54.7%) had high expression of HIF-2α. The SUVmax was significantly different in the HIF-2α expression subgroups (p < 0.001). SUVmax emerged as the most significant parameter to differentiate HIF-2α expression subgroups (high vs. low), with the AUC of 0.93 (95% CI 0.85-1.00, p < 0.001), sensitivity of 90%, and specificity of 88%. Furthermore, SUVmax was confirmed as the most significant predictor of HIF-2α expression level by univariable logistic regression model analysis (odds ratio 1.39, 95% CI 1.17-1.65, p < 0.001). Consistent with the radiographic results of [68Ga]Ga-PSMA-11 PET/CT, the staining intensity of pathological PSMA was significantly higher in HIF-2α-high-expressing tumors (p = 0.003). [68Ga]Ga-PSMA-11 PET/CT was superior in identifying pathological HIF-2α expression in primary tumors of RCC patients, demonstrating its potential application in predicting responses to HIF-2α antagonists. • [68Ga]Ga-PSMA-11 PET/CT could potentially predict the HIF-2α expression of primary tumors among patients with RCC. • SUVmaxof [68Ga]Ga-PSMA-11 PET/CT was the most significant predictor of HIF-2α expression level. • This probability could help predict the therapeutic response of patients with RCC to HIF-2α antagonists.

Differences between volumetric and areal porosities within different vertical regions of permeable concrete pavement

ABSTRACT This study quantitatively showed the differences between volumetric and areal porosities versus the number of applied areal porosities within different vertical regions, and a suitable number of applied areal porosities was proposed to accurately represent the volumetric porosity. The volumetric or areal porosities within five equal vertical regions from each specimen were determined using the slice-water displacement method, slice-image analysis, or computed tomography (CT) scanning. The measurements indicated that near the top or bottom surface, the porosity increased sharply as the surface was approached because of wall effects. The boundary of the region influenced by wall effects is located 1.70–2.36 mm from the top or bottom surface. The wall effect-caused increased porosities range from 1.09% to 1.51% for the top region, whereas they range from 0.51% to 0.73% for the bottom region. For the five regions and the complete specimen, the differences between volumetric and areal porosities and their fluctuations were typically larger when the number of applied areal porosities was fewer, and the maximum absolute differences were well fit by decreasing power curves.

On two goby-associated snapping shrimps from the Red Sea, one of them new to science (Malacostraca: Decapoda: Alpheidae: Alpheus).

Two snapping shrimps associated with gobies are reported from the Saudi Arabian coast of the Red Sea. Alpheus karplusi sp. nov., a species with a highly diagnostic, rusty-spotted colour pattern, is described based on three specimens, two males and one female, collected in the Farasan Islands and off Thuwal. Alpheus thompsoni Anker, 2022, previously known with certainty only from Papua New Guinea, is reported from the Farasan Islands, on the basis of a complete adult male specimen. Some differences in the colour pattern and morphology between the female holotype from Papua New Guinea and the male from the Red Sea are discussed. Both species belong to the A. djeddensis Coutire, 1897A. djiboutensis De Man, 1909 species complex, which also includes A. bellulus Miya Miyake, 1969, A. macellarius Chace, 1988, A. fenneri Bruce, 1994, A. mannarensis Purushothaman, Abhilash, Kumar Lal, 2021, and A. sciolii Anker, 2022.

Isolation and identification of proteolytic lactic-acid bacteria of the common carp (Cyprinus carpio) by spontaneous fermentation to obtain functional peptides.

High proteolytic activity and several biological functions (antimicrobial, antioxidant, antihypertensive, among others) have been attributed to lactic-acid bacteria (LAB) isolated from fish and peptides obtained from proteolysis. Therefore, the objective of this research was isolating, characterizing, and identifying LAB with proteolytic activity by spontaneous fermentation from common carp (Cyprinus carpio) reared in ponds and wild ones obtained from Lago de Chapala, Jalisco, Mexico. Spontaneous fermentation from complete carp specimens was observed, considering two sampling points (skin and intestines) at 15°C at 5 and 10days. Isolated LAB-from both reared and wild specimens-were identified and morphologically characterized; identification was performed by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). Proteolytic activity was assessed by the presence of the proteolytic halo. A total of five genera and eight different LAB proteolytic species were isolated from all the carp samples. At 10days, greater proteolytic LAB diversity was obtained from the intestine (Tukey's, p < 0.05); the proteolytic halo with the greatest diameter was recorded in wild carp skin with Lactiplantibacillus plantarum S5P2 (2.8cm) at 5days of fermentation, followed by Leuconostoc mesenteroides S5I1 (2.73cm) and Leuconostoc pseudomesenteroides S5P2 (2.66cm) (p < 0.05). In conclusion, proteolytic capability of LAB isolated from carp (Cyprimus carpio)-both wild and reared-is influenced by the ecosystem where they develop. These proteolytic LAB may be used in biotechnological industries to obtain bioactive peptides by fermenting substrates rich in proteins.

Cranial anatomy and systematics of Dendrerpeton cf. helogenes (Tetrapoda, Temnospondyli) from the Pennsylvanian of Joggins, revisited through micro‐CT scanning

AbstractThe Joggins Fossil Cliffs constitute an upper Carboniferous (Pennsylvanian) locality in Nova Scotia (Canada). This site, known for the rich record of fossils preserved in the palaeoenvironment in which they lived, sheds light on the late Carboniferous environment. More specifically, Joggins records one of the earliest Pennsylvanian ecosystems and is unique in preserving a rich diversity of terrestrial fauna compared with other Pennsylvanian communities, which mostly preserve aquatic fauna. For vertebrate palaeontology, the significance of Joggins lies in the discovery of the earliest amniotes (Hylonomus lyelli Dawson, Protoclepsydrops haplous Carroll, and Asaphestera platyris (Steen)) and the second earliest temnospondyl, Dendrerpeton (only Balanerpeton woodi Milner &amp; Sequeira occurs earlier). Computed tomography of the most complete tetrapod specimen found at Joggins, the temnospondyl amphibian currently referred to Dendrysekos helogenes Steen, made accessible the internal anatomy and revealed previously obscured anatomical structures, including the stapes, scleral plates, and partial sphenethmoid. These newly accessible features enabled a redescription of this specimen. The resulting anatomical comparisons and phylogenetic analyses suggest that the genus Dendrysekos is a junior synonym of Dendrerpeton; the diagnostic characters previously distinguishing the two genera are considered to be instead a combination of ontogenetic and preservational parameters, and the two genera were not resolved as discrete. Additionally, the phylogenetic analyses show that the interrelationships between the main early temnospondyl groups (Edopoidea, Dvinosauria, Eryopoidea and Dissorophoidea) are neither robust nor well supported, due to the low number of shared derived characters.

Neoadjuvant pertuzumab in non‑metastatic HER2‑positive breast tumors: Multicentric study in Peru (NeoHer)

Several clinical trials have demonstrated the benefit of adding pertuzumab to trastuzumab plus neoadjuvant chemotherapy in the treatment of human epidermal growth factor receptor 2 (HER2)-positive breast cancer. The comparison of outcomes between nonrandomized groups of patients who received similar treatments in routine practice remains difficult. The present study aimed to evaluate the pathological complete response (pCR) rates achieved with pertuzumab among patients in routine clinical care in Peru using real-world data. The definition of pCR used was the absence of residual invasive cancer from the complete resected breast specimen and all sampled regional lymph nodes following completion of neoadjuvant systemic therapy. A total of 44 patients with non-metastatic HER2-positive breast cancer (stages II and III) treated with pertuzumab in the neoadjuvant setting and who underwent surgery at three private clinics in Lima (Peru) were retrospectively evaluated. The pCR was the efficacy endpoint and it was determined and compared with the results from other clinical trials. Furthermore, safety data were described. The median age was 44 years (interquartile range, 39.5-50.5 years) and 65.9% of patients were premenopausal. Regarding the clinical stage, 56.8% were IIA/IIB and 36.4% were IIIA/IIIB/IIIC. All treatment schemes included concurrent trastuzumab. The patients' treatment comprised neoadjuvant therapy of docetaxel/trastuzumab/pertuzumab (THP) with a median of 4 cycles in 30 patients (68.2%) or docetaxel/trastuzumab/pertuzumab/carboplatin (THPCarb) with a median of 6 cycles in 14 patients (31.8%). In total, 70.5% of patients experienced pCR; among hormone receptor-negative cases, 75.0% achieved pCR and in tumors expressing hormone receptors, the rate of pCR was 66.7%. Of those patients subjected to neoadjuvant treatment with THP, 66.7% (20/30) achieved pCR, whereas 78.6% (11/14) of patients who received THPCarb had a pCR. The incidence of drug-related adverse events was 59.1% and in none of the patients, administration was discontinued due to toxicity. The present results of Peruvian patients with HER2 breast cancer treated according to clinical routine demonstrated that dual blockade of HER2 with trastuzumab and pertuzumab in the neoadjuvant setting achieved high rates of pCR even in hormone receptor-positive patients. These results are consistent with those of randomized controlled trials, with a good safety profile.

The first complete specimen of the deep-water shrimp Batella praecipua De Grave, 2004 (Crustacea: Decapoda: Alpheidae).

The deep-water alpheid shrimp Batella praecipua De Grave, 2004 was originally described based on two incomplete specimens, both with their first chelipeds missing, collected at 400440 m off New Caledonia. During the recent KANADEEP 1 expedition in the Coral Sea in 2017, the first complete specimen of B. praecipua was collected at a depth of 370380 m. The morphology of this specimen is presented in detail, with emphasis on the highly diagnostic chelipeds, which are described and illustrated for the first time. A slight intraspecific variation of B. praecipua is reported and a DNA barcode (CO1) is provided for this species. The main differences between the three presently known species of Batella Holthuis, 1955 are discussed.

Philophthalmus hechingeri n. sp. (Digenea: Philophthalmidae), a Human-Infecting Eye Fluke from the Asian Mud Snail, Batillaria attramentaria

Two cases of human philophthalmosis have been reported in Japan. Gravid flukes removed from the eyes of the patients were broken, but their morphological characteristics suggest that an unknown species of the genus Philophthalmus is involved as a pathogen for humans. The mitochondrial DNA barcode of the human eye fluke enabled us to discover its larval stage from the Japanese mud snail, Batillaria attramentaria. The discovered cercaria had previously been temporarily described as "Philophthalmid sp. I." In this study, we examined the infection status of B. attramentaria with Philophthalmid sp. I found on a muddy seashore of the Seto Inland Sea, Japan, and the resulting metacercariae were experimentally administered to Japanese quails to develop them into the gravid adult stage. The complete specimens of the adult and larval stages allowed us to describe a new species. Based on morphological and molecular analyses, Philophthalmus hechingeri n. sp. is proposed for the human-infecting eye fluke in Japan. The natural definitive hosts of the new species are unknown. However, the habitat of B. attramentaria suggests that shorebirds (seagulls, sandpipers, and plovers) might be the possible candidates.

Typology of Roman Urns in the Antiquities Collection of the National Museum of Bosnia and Herzegovina

This paper treats various forms of Roman urn, evidence of cremation as a customary manner of burial in what is now Bosnia and Herzegovina. The Antiquities Department of the National Museum of Bosnia and Herzegovina holds the largest collection of Roman urns of various types and dates: 76 complete or fragmentary specimens. The urns may be classified in terms of material into glass, pottery and stone urns. Several different forms are identified within each group. The most diverse are stone urns, which may be square, rectangular box-shaped and sarcophagus-like, or cylindrical.

“Crack under pressure”—Inducing life-like mandible fractures as a potential benefit to surgical education in oral and maxillofacial surgery

The aim of this study was to investigate whether life-like fractures of human cadaveric mandibles with a focus on the condylar process and the intact soft tissue envelope could be simulated.A total of nine fresh-frozen human head specimens were fractured in a custom-made drop-test bench. This reproducible method is based on a weight falling from a defined height onto the fixed specimens, simulating a direct blow to the symphysis of the mandible. All the fractures were analyzed by fluoroscopy and CT-scans.In all the specimens that were included in this study, several typical lesions could be created, resulting in a total of 27 mandible fractures. Seven condylar head fractures with intracapsular fracture patterns, three high, two low and five subcondylar fractures as well as different corpus fractures occurred. Human cadaveric mandibles as part of a complete head specimen with intact soft tissue can be successfully fractured by means of a drop-test bench setup. The amount of load and the exact angle at which the load is applied seem to be of high relevance. Such fractured specimens can be implemented in surgical education courses to teach and improve osteosynthetic techniques.