[Case report: an exceptional case of a monozygotic thoracopagus parasiticus in a German Holstein calf]

A black and white German Holstein calf displayed a complex double malformation in shape of a thoracopagus parasiticus. By means of a molecular genetic investigation the genesis of the malformation from one zygote could be demonstrated. Both vertebral columns showed a pronounced lordosis, with the vertebral column of one animal ending in a rudimentary head. Close to this rudiment two derivates of branchial arches were found. The two thoracic cavities merged into one "thorax". In the shared thoracic cavity one heart was found. In its right atrium, a cherry-sized structure was found in which heart- and vascular smooth muscles were demonstrated histologically. The aorta split shortly after its origin to provide both animals with one aorta each. The larger pair of lungs was connected with a trachea leading to the head while the smaller pair of lungs originated from a trachea deriving from the rudimentary head. The diaphragm jejunum and split afterwards. The pedigree of the affected animal showed neither inbreeding nor any other affected animal.

Vascular endothelial cell-specific phosphotyrosine phosphatase (VE-PTP) activity is required for blood vessel development

VE-PTP, a receptor-type phosphotyrosine phosphatase, associates with the tyrosine kinase receptor Tie-2 and VE-cadherin and enhances the adhesive function of the latter. Here, VE-PTP was found to be restricted to endothelial cells, with a preference for arterial endothelium. Mutant mice expressing a truncated, secreted form of VE-PTP lacking the cytoplasmic and transmembrane domains and the most membrane-proximal extracellular fibronectin type III repeat, showed severe vascular malformations causing lethality at 10 days of gestation. Although blood vessels were initially formed, the intraembryonic vascular system soon deteriorated. Blood vessels in the yolk sac developed into dramatically enlarged cavities. In explant cultures of mutant allantoides, endothelial cells were found next to vessel structures growing as cell layers. No signs for enhanced endothelial apoptosis or proliferation were observed. Thus, the activity of VE-PTP is not required for the initial formation of blood vessels, yet it is essential for their maintenance and remodeling.

Microhardness and marginal adaptation of pre-warmed composites

Objectives: The aim of this study was to examine the effect of pre-warmed composite on the microhardness and marginal adaptation. Methods: Ninety six identical class II cavities were prepared in extracted human molars and filled/cured in three 2 mm increments using a metal matrix. Two composites (Tetric Evo Ceram (IvoclarVivadent) and ELS(Saremco)) were cured with a LED curing unit (Bluephase (IvoclarVivadent)) using curing cycles of 20 and 40 seconds. The composite was used at room temperature or pre-warmed at 54.5ºC (Calset(AdDent)). Twelve teeth were filled for every composite-curing time-composite temperature combination. The teeth were thermocycled (1000 cycles at 5º and 55ºC) and then stored at 37° C for seven days . Dye penetration (basic fuchsine 5% for 8 hours) was measured using a score scale. Knoop microhardness was determined 100, 200, 500, 1000, 1500, 2500, 3500, 4500 and 5500µm from the occlusal surface at a distance of 150 and 1000µm from the metal matrix. The total degree of polymerization of a composite specimen was determined by calculating the area under the hardness curve. Results: Statistical analyses showed no difference in marginal adaptation (p>0.05). Hardness values at 150µm from the matrix were lower than those at 1000µm. There was an increase of the microhardness at the top of each increment and decrease towards the bottom of each increment. Longer curing times resulted in harder composite samples. Multiple linear regression showed that only the curing time (p<0.001) and composite material (p<0.001) had a significant association with the degree of polymerization. The degree of polymerization was not influenced by pre-warming the composite at a temperature of 54.5ºC (p=4.86). Conclusion: Polymerization time can not be reduced by pre-warming the composite on a temperature of 54.5ºC. The marginal adaptation is not compromised by pre-warming the composite.

Influence of beveling and ultrasound application on marginal adaptation of box-only Class II (slot) resin composite restorations

A laboratory study was performed to assess the influence of beveling the margins of cavities and the effects on marginal adaptation of the application of ultrasound during setting and initial light curing. After minimal access cavities had been prepared with an 80 microm diamond bur, 80 box-only Class II cavities were prepared mesially and distally in 40 extracted human molars using four different oscillating diamond coated instruments: (A) a U-shaped PCS insert as the non-beveled control (EMS), (B) Bevelshape (Intensiv), (C) SonicSys (KaVo) and (D) SuperPrep (KaVo). In groups B-D, the time taken for additional bevel finishing was measured. The cavities were filled with a hybrid composite material in three increments. Ultrasound was also applied to one cavity per tooth before and during initial light curing (10 seconds). The specimens were subjected to thermomechanical stress in a computer-controlled masticator device. Marginal quality was assessed by scanning electron microscopy and the results were compared statistically. The additional time required for finishing was B > D > C (p < or = 0.05). In all groups, thermomechanical loading resulted in a decrease in marginal quality. Beveling resulted in higher values for "continuous" margins compared with that of the unbeveled controls. The latter showed better marginal quality at the axial walls when ultrasound was used. Beveling seems essential for good marginal adaptation but requires more preparation time. The use of ultrasonic vibrations may improve the marginal quality of unbeveled fillings and warrants further investigation.

Intentional replantation for the management of maxillary sinusitis

AIM: To present a case that emphasizes the importance of the use of intentional replantation as a technique to successfully treat a periapical lesion and an odontogenic maxillary sinusitis through the alveolus at the same time. SUMMARY: This case report presents a patient with odontogenic maxillary sinusitis secondary to periapical disease of a maxillary molar that had previously received root canal treatment. The molar was extracted, with drainage and rinsing of the maxillary sinus. The apices were resected extra-orally, the retrograde cavities prepared with ultrasound and retrograde fillings of silver amalgam placed. The tooth was then replanted. After 2 years, the patient was asymptomatic, periapical radiography showed no evidence of root resorption and computed tomography scanning demonstrated the resolution of maxillary sinusitis. Key learning points: *When root canal treatment or periapical surgery cannot be undertaken or has failed, intentional replantation may be considered. *This alternative treatment may be predictable in certain cases.

Effect of shortening the barrel in contact shots from rifles and shotguns

In a suicidal gunshot fired to the chest from a carbine, the barrel of which had been shortened to half its original length, an unexpectedly large degree of destruction of the anterior thoracic wall with extensive undermining of the subcutis was found. This phenomenon was investigated for reconstructive purposes by firing test shots from two different long guns (caliber 7.92 x 57 repeating rifle with full-jacketed pointed bullet and caliber 12/70 single-barreled shotgun with shotgun slug) into blocks of soap (38 x 25 x 25 cm). The contact shots were fired before and after shortening the barrels (repeating rifle from 60 to 30 cm and single-barreled shotgun from 72 to 36 cm). The volume of the cavities in the simulant was visualized three-dimensionally with the help of a multislice computed tomography (CT) scanner and calculated sectionally. With the repeating rifle and the single-barreled shotgun, the shots from the sawed-off barrels produced significantly larger cavity diameters in the first section of the bullet track. This effect is attributable to the fact that, with a shortened barrel, the gas pressure at the muzzle is higher, thus, leading to increased expansion in the initial part of the wound track in contact shots.

Hypervascular liver tumors: low tube voltage, high tube current multi-detector row CT for enhanced detection--phantom study

PURPOSE: To prospectively evaluate, for the depiction of simulated hypervascular liver lesions in a phantom, the effect of a low tube voltage, high tube current computed tomographic (CT) technique on image noise, contrast-to-noise ratio (CNR), lesion conspicuity, and radiation dose. MATERIALS AND METHODS: A custom liver phantom containing 16 cylindric cavities (four cavities each of 3, 5, 8, and 15 mm in diameter) filled with various iodinated solutions to simulate hypervascular liver lesions was scanned with a 64-section multi-detector row CT scanner at 140, 120, 100, and 80 kVp, with corresponding tube current-time product settings at 225, 275, 420, and 675 mAs, respectively. The CNRs for six simulated lesions filled with different iodinated solutions were calculated. A figure of merit (FOM) for each lesion was computed as the ratio of CNR2 to effective dose (ED). Three radiologists independently graded the conspicuity of 16 simulated lesions. An anthropomorphic phantom was scanned to evaluate the ED. Statistical analysis included one-way analysis of variance. RESULTS: Image noise increased by 45% with the 80-kVp protocol compared with the 140-kVp protocol (P < .001). However, the lowest ED and the highest CNR were achieved with the 80-kVp protocol. The FOM results indicated that at a constant ED, a reduction of tube voltage from 140 to 120, 100, and 80 kVp increased the CNR by factors of at least 1.6, 2.4, and 3.6, respectively (P < .001). At a constant CNR, corresponding reductions in ED were by a factor of 2.5, 5.5, and 12.7, respectively (P < .001). The highest lesion conspicuity was achieved with the 80-kVp protocol. CONCLUSION: The CNR of simulated hypervascular liver lesions can be substantially increased and the radiation dose reduced by using an 80-kVp, high tube current CT technique.

Ultra-high-resolution dual-source CT for forensic dental visualization-discrimination of ceramic and composite fillings

Dental identification is the most valuable method to identify human remains in single cases with major postmortem alterations as well as in mass casualties because of its practicability and demanding reliability. Computed tomography (CT) has been investigated as a supportive tool for forensic identification and has proven to be valuable. It can also scan the dentition of a deceased within minutes. In the present study, we investigated currently used restorative materials using ultra-high-resolution dual-source CT and the extended CT scale for the purpose of a color-encoded, in scale, and artifact-free visualization in 3D volume rendering. In 122 human molars, 220 cavities with 2-, 3-, 4- and 5-mm diameter were prepared. With presently used filling materials (different composites, temporary filling materials, ceramic, and liner), these cavities were restored in six teeth for each material and cavity size (exception amalgam n = 1). The teeth were CT scanned and images reconstructed using an extended CT scale. Filling materials were analyzed in terms of resulting Hounsfield units (HU) and filling size representation within the images. Varying restorative materials showed distinctively differing radiopacities allowing for CT-data-based discrimination. Particularly, ceramic and composite fillings could be differentiated. The HU values were used to generate an updated volume-rendering preset for postmortem extended CT scale data of the dentition to easily visualize the position of restorations, the shape (in scale), and the material used which is color encoded in 3D. The results provide the scientific background for the application of 3D volume rendering to visualize the human dentition for forensic identification purposes.

Common and unexpected findings in mummies from ancient Egypt and South America as revealed by CT

Computed tomography (CT) has proved to be a valuable investigative tool for mummy research and is the method of choice for examining mummies. It allows for noninvasive insight, especially with virtual endoscopy, which reveals detailed information about the mummy's sex, age, constitution, injuries, health, and mummification techniques used. CT also supplies three-dimensional information about the scanned object. Mummification processes can be summarized as "artificial," when the procedure was performed on a body with the aim of preservation, or as "natural," when the body's natural environment resulted in preservation. The purpose of artificial mummification was to preserve that person's morphologic features by delaying or arresting the decay of the body. The ancient Egyptians are most famous for this. Their use of evisceration followed by desiccation with natron (a compound of sodium salts) to halt putrefaction and prevent rehydration was so effective that their embalmed bodies have survived for nearly 4500 years. First, the body was cleaned with a natron solution; then internal organs were removed through the cribriform plate and abdomen. The most important, and probably the most lengthy, phase was desiccation. After the body was dehydrated, the body cavities were rinsed and packed to restore the body's former shape. Finally, the body was wrapped. Animals were also mummified to provide food for the deceased, to accompany the deceased as pets, because they were seen as corporal manifestations of deities, and as votive offerings. Artificial mummification was performed on every continent, especially in South and Central America.

Low-grade endometrial stromal sarcoma with inferior vena cava tumor thrombus and intracardiac extension: radical resection may improve recurrence free survival

BACKGROUND: Endometrial stromal sarcoma (ESS) represents 0.2% of all uterine malignancies. Based on the mitotic activity, a distinction is made between low and high-grade ESS. Although the overall five-year survival rate for low-grade ESS exceeds 80%, about 50% of the patients show tumor recurrence, mostly after a long latency period. Tumor invasion of the great vessels is extremely rare. We describe a patient with advanced low-grade ESS with tumor invasion of the infrarenal aorta and the inferior vena cava. The patient presented with a large tumor thrombus extending from the inferior vena cava into the right atrium. METHODS: Review of literature and identification of 19 patients, including our own case report, with advanced low-grade ESS with invasion of the great vessels and formation of an inferior vena cava tumor thrombus. RESULTS: All 19 patients presented with an abdominal tumor mass and a tumor thrombus protruding into the inferior vena cava. The tumor thrombus extended into the right heart cavities in nine patients reaching the right atrium in four, the right ventricle in three and the pulmonary artery in two patients. There were 5 patients with an advanced primary tumor and 14 patients with an advanced recurrent tumor. Seven patients presented with synchronous metastatic disease and six patients with a pelvic tumor infiltrating the bladder, the rectosigmoid colon or the infrarenal aorta. Mean age at surgery was 45.9+/-12.3 years (median 47, range 25-65 years). Tumor thrombectomy was accomplished by cavatomy or by right atriotomy after installation of a cardiopulmonary bypass. There was no peri-operative mortality and a very low morbidity. Radical tumor resections were achieved in 10 patients. The follow-up for these 10 patients was 2+/-1.3 years (median 2, range 0.3-4.5 years). Nine patients remained recurrence free whereas one patient suffered an asymptomatic local recurrence. CONCLUSIONS: Low-grade ESS is a rare angioinvasive tumor with a high recurrence rate. Resection of an inferior vena cava tumor thrombus, even with extension into the right heart cavities, can be performed safely. Extensive radical surgery is therefore justified in the treatment of advanced tumor manifestations of a low-grade ESS potentially improving recurrence free survival.

Anterior Stafne's bone cavity mimicking a periapical lesion of endodontic origin: report of two cases

INTRODUCTION: This report of 2 cases describes the diagnostic procedures used to identify 2 Stafne's bone cavities (SBC) found in unusually anterior locations in the mandible, both mimicking periapical lesions of endodontic origin. METHODS: In the first patient, a 47-year-old man, an SBC was diagnosed in the area of teeth #27, 28, and 29. In the second patient, a 62-year-old man, the SBC was a fortuitous finding, because this patient was referred for dental implant therapy. RESULTS: In both cases, the final diagnosis was achieved by using limited cone beam computed tomography (CBCT) and magnetic resonance imaging (MRI). In both patients, the lingual bone cavity was found to be occupied by accessory salivary gland tissue. CONCLUSIONS: The combination of CBCT and MRI as noninvasive diagnostic techniques seems ideal to avoid surgical explorations, incisional biopsies, or enucleations of the lesion for diagnostic purposes.

[The patent nasopalatine duct. A rare anomaly and diagnostic pitfall]

The patent nasopalatine duct is a rare anomaly in the anterior maxilla. During the early fetal period, a bilateral and epithelium-lined duct is formed within the primary palatal process as an oro-nasal communication. However, the duct obliterates and degenerates before birth. A persisting patent or through-and-through nasoplatine duct is therefore considered a developmental anomaly. A patent nasopalatine duct normally presents as one (or two) tiny openings lateral or posterior to the incisive papilla. In such a case, the ducts can be partially or completely probed with gutta-percha points with subsequent radiographic imaging. The patients report strange sensations such as squeaking noise, palatal drainage, nasal regurgitation, or airway communication between nasal and oral cavities; however, patients rarely complain about pain. About 40 cases have been documented in the literature. We describe two patients who have been referred to our department for evaluation of "sinus tracts" in the anterior palate. Since a patent nasopalatine duct can become a diagnostic pitfall, a thorough inspection of the mucosa around the incisive papilla is essential to avoid unnecessary endodontic or surgical interventions in the area of the central maxillary incisors.

Laser wavelengths and oral implantology

In modern implant dentistry there are several clinical indications for laser surgery. Different laser systems have a considerable spectrum of application in soft and hard peri-implant tissues. The literature was searched for clinical application of different laser wavelengths in peri-implant tissues: second-stage surgery of submerged implants, treatment of infrabony defects, removal of peri-implant hyperplastic overgrowths, and, possibly, the preparation of bone cavities for implant placement. This report describes the state-of-the-art application of different laser systems in modern implant dentistry for the treatment of peri-implant lesions and decontamination of implant surfaces. Our study evaluated in vitro examinations, clinical experience and long-term clinical studies. The exact selection of the appropriate laser system and wavelength was dependent on the scientific evaluation of recent literature and the level of changes in implant and tissue temperatures during laser application. The significant reduction in bacteria on the implant surface and the peri-implant tissues during irradiation and the cutting effects associated with the coagulation properties of the lasers are the main reasons for laser application in the treatment of peri-implant lesions and the successful long-term prognosis of failing oral implants. The various applications of lasers in implant dentistry are dependent on the wavelength and laser-tissue interactions.

Comparison of the immediate effects of gaseous ozone and chlorhexidine gel on bacteria in cavitated carious lesions in children in vivo

Clinical application of ozone gas has been shown to arrest the progression of dentinal caries in children. In this study, we compare the immediate effects of gaseous ozone and chlorhexidine gel on bacteria in cavitated carious lesions in children. Forty children, each with at least two open occlusal carious lesions, were enrolled in the study. Two teeth were chosen randomly. In one lesion, overlying soft biological material was removed, whilst the other lesion was not excavated. Cavities were rinsed with sterile water and dried with air. A standardised sample was taken from the mesial part of each lesion. Then, gaseous ozone (HealOzone) or 1% chlorhexidine gel (Corsodyl) was applied for 30 s on both lesions of 20 children each, and a second sample was taken from the distal part of each lesion. The anaerobic microbiota was cultivated; the number of colony forming units was calculated per milligram sample. The two-sided paired t test showed no significant (P > 0.05) differences in the reduction of total bacterial counts per milligram comparing samples before and after ozone or chlorhexidine application. The tests also showed no statistically significant difference whether the superficial decayed dentine had been removed before ozone or with chlorhexidine treatment or not. It can be concluded that gaseous ozone or chlorhexidine gel application for 30 s to deep occlusal carious cavities had no significant immediate antimicrobial effects whether the superficial decayed layers dentine were removed or not.

Antibiotic resistance and genetic diversity in Staphylococcus aureus from slaughter pigs in Switzerland

Nasal carriage of Staphylococcus aureus was evaluated in pigs at slaughterhouse. The nasal cavities of 304 pigs from 54 herds were screened. Eighty-nine percent of the farms harbored pigs that were colonized with S. aureus. Among them, no MRSA were found, indicating a low prevalence. However, pigs were found to harbor S. aureus, which displayed resistance to penicillin (blaZ) (62.5%), tetracycline [tet(M)] (33.3%), streptomycin (strpS194) (27%), clindamycin [erm(B)] (4.1%), erythromycin [erm(B)] (4.1%), kanamycin (4.1%), chloramphenicol (catpC194) (2%) and gentamicin [aac(6')-Ie-aph(2')-Ia] (2%). The S. aureus isolates mainly belong to Ridom spa type t034 (31.3%), t208 (14.6%) and t899 (12.5%). These pig-associated spa types have not yet been detected in hospitalized human patients in Switzerland. Surveillance programs are now necessary at both inland and import levels to rapidly detect and suppress the emergence of MRSA in pigs in Switzerland.