Recommended centrifuge method: Specific grain size separation in the <63 µm fraction of marine sediments.

The isolation of specific grain size classes of lithogenic samples and biogenic carbonate from the <63 µm fraction (i.e. clay and silt) of marine sediment is often a prerequisite to further pre-treatments and/or analytical measurements for palaeoceanographic studies.

Development of Thickness-Dependent Predictive Methods for the Estimation of the CIEL*a*b* Color Coordinates of Monolithic and Layered Dental Resin Composites.

Usually, dentin and enamel shades are layered in dental restorations with the purpose of mimicking the natural appearance of teeth. The main objective of this study was to develop and assess accuracy of a color-prediction method for both monolithic and layered dental resin-based composites with varying shades and under different illuminants. A total of 15 different shades of VITAPAN Excell, VITAPAN Dentine and VITA Physiodens as well as VITA Enamel of five different thicknesses (0.

Color prediction of layered dental resin composites with varying thickness.

Objective: The aim of this study was to assess the accuracy of a Principal Components Analysis (PCA)-based method for reflectance reconstruction and color estimation of layered dental resin-based composites with different thicknesses.

Method: Bi-layered samples of different clinically relevant thicknesses were created using shades of VITAPAN Excell (VE), VITAPAN Dentine (VD) and VITA Physiodens (VP), combined with their corresponding enamel shades. Spectral reflectance of all samples was measured over a black background using a non-contact spectroradiometer with CIE 45∕0 geometry.

Reflectance and color prediction of dental material monolithic samples with varying thickness.

Objective: To assess accuracy of reflectance reconstruction and color estimation of different dental materials with varying thicknesses using Principal Component Analysis (PCA).

Method: A1, A2, A3, A3.5, B2, C2 and D2 shades and 5 thicknesses (within 0.

Indo-Pacific Walker circulation drove Pleistocene African aridification.

Today, the eastern African hydroclimate is tightly linked to fluctuations in the zonal atmospheric Walker circulation. A growing body of evidence indicates that this circulation shaped hydroclimatic conditions in the Indian Ocean region also on much longer, glacial-interglacial timescales, following the development of Pacific Walker circulation around 2.2-2.

Antarctic icebergs reorganize ocean circulation during Pleistocene glacials.

The dominant feature of large-scale mass transfer in the modern ocean is the Atlantic meridional overturning circulation (AMOC). The geometry and vigour of this circulation influences global climate on various timescales. Palaeoceanographic evidence suggests that during glacial periods of the past 1.

[Migration of a retained premolar into the processus muscularis of the mandible].

Migration of an impacted mandibular premolar is a rare finding, whereas dystopia of lower jaw cuspids is described much more often in the literature. We present a patient in whom radiographic studies show the migration of a mandibular premolar to the muscular process over a period of 14 years. Most of the tooth migration along the vertical portion of the mandibula into the processus muscularis took place after the root development had ended.

[Acceptance: scientific cultural aspects].

In highly developed industrial societies the acceptance of risk is in decline. The reasons for this are connected in elementary fashion with the fact of modern life. Their effects may be considered irreversible, and pep talks under the motto "dare to risk!" are probably of no avail; we must adapt ourselves to declining risk acceptance.

Cost comparison between two modes of Palmaz Schatz coronary stent implantation: transradial bare stent technique vs. transfemoral sheath-protected stent technique.

Coronary Palmaz Schatz stent implantation is usually performed by using the sheath protected stent delivery system (SDS) via the percutaneous transfemoral route. However, downsizing of PTCA equipment made transradial coronary stenting feasible. Bare stent implantation, 6F technique, increased patient mobility, reduced vascular complications and reduced hospital stay may increase cost effectiveness of this novel technique.

Plasma-sprayed coatings of tetracalciumphosphate, hydroxyl-apatite, and alpha-TCP on titanium alloy: an interface study.

In order to study the interaction of calcium phosphate coatings with bone tissue, coated titanium cylinders with a standard size were implanted in dog femora. Coatings were made by plasma spraying powders of hydroxylapatite, beta-whitlockite, and tetracalciumphosphate particles. The plasma spraying process turns beta-whitlockite into alpha-TCP.

Histological evaluation of biocompatible orthopaedic polymer.

The biocompatibility of biocompatible orthopaedic polymer implant materials was studied in subcutaneous and bony tissue of rats and rabbits. The tissue response was evaluated by histological techniques. No bone induction capacity of biocompatible orthopaedic polymer could be observed.

Tissue response to percutaneous implants in rabbits.

This study reports on certain aspects of wound-healing around percutaneous implants. Plasma-sprayed and dense hydroxylapatite, titanium, and carbon test implants were inserted into the tibia and the cranium of 12 rabbits. Four and 8 months after insertion, the animals were sacrificed and the implants with their surrounding tissues were processed histologically.

Rib fracture healing after osteosynthesis with wire mesh titanium and screws: a histological study in sheep.

Twenty sheep were placed under general anesthesia and five ribs (6-10) were transected at their lateral angle using a pair of rib shears. The fractures were stabilized by titanium wire mesh plates. After 4, 6, 8, 10 and 12 weeks groups of 4 animals were sacrificed and rib samples were prepared for histological examinations.

A simple method for preparing thin (10 microM) histological sections of undecalcified plastic embedded bone with implants.

A simple method for preparing undecalcified thin sections of bone with implants has been developed. After exposing a surface of bone and implant in a plastic block by sawing thick sections, the surface is stained prior to making a thin section. A glass coverslip is affixed with a thin layer of cement to the stained surface to stabilize the tissue and implant during sectioning.

A plastic composite of alginate with calcium phosphate granulate as implant material: an in vivo study.

A comparison of calcium phosphate granulate with a composite of alginate and calcium phosphate granulate, shows that the composite has less particle migration, less biodegradation and better handling properties. The tissue response to both materials is similar.

A comparative study of different beta-whitlockite ceramics in rabbit cortical bone with regard to their biodegradation behaviour.

Different beta-whitlockite ceramic cylinders of standard size were implanted in the tibiae of rabbits to study the influence of micropores and chemistry on the biodegradation rate. The materials were evaluated by radiography and light microscopy. Surface chemistry was varied by the addition of impurities, while different applied pressures before sintering and different sintering temperatures gave rise to different micropores.

Interaction of biodegradable beta-whitlockite ceramics with bone tissue: an in vivo study.

The biodegradation of different porous beta-whitlockite materials are studied by in vivo experiments, radiographic follow-ups and light microscopy observations. The materials were implanted in rabbit tibiae for 16 month. Micropores play an important role in the biodegradation rate.

[Growth of the jaw after preoperative orthodontic treatment of cleft lip and cleft palate].

In 48 patients a systematized therapeutic model plan for the preoperative and postoperative orthodontic treatment of patients with unilateral or bilateral cleft lips and palates is pursued. In addition to stimulation and growth control of the maxillary alveolar segments in a transverse direction and at the segment poles, increasing sagittal development is observed in a later developmental phase.

[Studies on the surgical and chemotherapeutic management of oral cancer].

Of the 101 patients who have been treated with bleomycin since 1971 two groups were formed: Group I: Preoperative chemotherapy with 345 mg bleomycin, followed by radical operation. Group II: 200 mg bleomycin preoperatively, followed by radical operation and postoperative chemotherapy up to a total dose of 345 mg bleomycin. 1.