The present study demonstrates that all the wavelengths investigated are suitable for the disinfection of even the deeper layers of dentin and may prove to constitute valuable tools in state-of-the-art endodontics.

Background and Objective:The aim of this study is to examine the long-term effect of diode laser therapy on periodontal pockets with regard to its bactericidal abilities and the improvement of periodontal condition. Study Design/Materials and Methods: Fifty patients were randomly subdivided into two groups (laser-group and controlgroup) and microbiologic samples were collected. There have been six appointments for 6 months following an exact treatment scheme. After evaluating periodontal indices (bleeding on probing, Quigley-Hein) including pocket depths and instruction of patients in oral hygiene and scaling therapy of all patients, the deepest pockets of each quadrant of the laser-group's patients were microbiologically examined. Afterwards, all teeth were treated with the diode laser. The control-group received the same treatment but instead of laser therapy were rinsed with H 2 O 2 . Each appointment also included a hygienic checkup. After 6 months the final values of the periodontal indices and further microbiologic samples were measured. The total bacterial count as well as specific bacteria, such as Actinobacillus actinomycetemcomitans, Prevotella intermedia, and Porphyromonas gingivalis, were assessed semiquantitatively. Results: The bacterial reduction with diode laser therapy was significantly better than in the control group. The index of bleeding on probing improved in 96.9% in the laser-group, whereas only 66.7% in the control group. Pocket depths could be more reduced in the laser group than in the control group. Conclusion:The diode laser reveals a bactericidal effect and helps to reduce inflammation in the periodontal pockets in addition to scaling. The diode laser therapy, in combination with scaling, supports healing of the periodontal pockets through eliminating bacteria.

Reverse transcription-PCR (RT-PCR) was used to detect canine distemper virus (CDV) nucleoprotein (NP) RNA in serum, whole blood, and cerebrospinal fluid (CSF) samples from 38 dogs with clinically suspected distemper. Results were correlated to clinical findings, anti-CDV neutralizing antibody titers, postmortem findings, and demonstration of CDV NP antigen by immunohistochemistry. The specificity of the RT-PCR was ensured by amplification of RNA from various laboratory CDV strains, restriction enzyme digestion, and Southern blot hybridization. In 29 of 38 dogs, CDV infection was confirmed by postmortem examination and immunohistochemistry. The animals displayed the catarrhal, systemic, and nervous forms of distemper. Seventeen samples (serum, whole blood, or CSF) from dogs with distemper were tested with three sets of primers targeted to different regions of the NP gene of the CDV Onderstepoort strain. Expected amplicons were observed in 82, 53, and 41% of the 17 samples, depending upon the primer pair used. With the most sensitive primer pair (primer pair I), CDV NP RNA was detected in 25 of 29 (86%) serum samples and 14 of 16 (88%) whole blood and CSF samples from dogs with distemper but not in body fluids from immunohistochemically negative dogs. Nucleotide sequence analysis of five RT-PCR amplicons from isolates from the field revealed few silent point mutations. These isolates exhibited greater homology to the Rockborn (97 to 99%) than to the Onderstepoort (95 to 96%) CDV strain. In summary, although the sensitivity of the RT-PCR for detection of CDV is strongly influenced by the location of the selected primers, this nucleic acid detection system represents a highly specific and sensitive method for the antemortem diagnosis of distemper in dogs, regardless of the form of distemper, humoral immune response, and viral antigen distribution.

Optical coherence tomography (OCT) has been developed during the last 10 years as a new noninvasive imaging tool and has been applied to diagnose different ocular and skin diseases. This technique has been modified for cross–sectional imaging of dental structures. In this first preliminary study the technique was applied to obtain tomographic images of extracted sound and decayed human teeth in order to evaluate its possible diagnostic potential for dental applications. Classical OCT images based on reflectivity measurements and phase retardation images using polarization–sensitive OCT were recorded. It was demonstrated that polarization–sensitive OCT can provide additional information which is probably related to the mineralization status and/or the scattering properties of the dental material. One of the attractive features of OCT is that it uses near–infrared light instead of ionizing radiation. Furthermore, high transversal and depth resolution on the order of 10 μm can be obtained. Present limitations, e.g. the limited penetration depth, and possible solutions are discussed.

Abstract. The automated laser-based hematology analyzer Sysmex XT-2000iV™ provides a 5-part differential count and specific cytograms that are of great interest for large veterinary laboratories. The aim of the study was to validate the Sysmex XT-2000iV compared to the laser-based hematology analyzer ADVIA® 2120 and manual differential in dogs, cats, and horses as well as the impact of anticoagulant (heparin, ethylenediamine tetra-acetic acid [EDTA], and citrate) and storage at 22°C and 4°C. Consecutive fresh K 3 -EDTA blood samples from 216 cats, 314 dogs, and 174 horses were included. The impact of anticoagulant and sample storage was assessed in specimens obtained from an additional 9 cats, 10 dogs, and 10 horses. Agreement between both analyzers was excellent to good except for monocytes and canine reticulocytes. Spearman rank correlation coefficients (r s ) between Sysmex XT-2000iV and manual differential were good to fair and ranged from 0.91 (cat lymphocytes) to 0.44 (cat monocytes). Hematocrit value (Hct), mean corpuscular hemoglobin (MCH), MCH concentration (MCHC; all: P < 0.001), and mean corpuscular volume (MCV; P < 0.01) were higher in canine citrated blood compared to heparin and EDTA. In cats, lymphocytes and monocytes were lower in heparinized blood compared to EDTA (P < 0.05), whereas in horses no significant effect was seen. Regarding storage time and temperature, white and red blood cell counts, hemoglobin, and MCH were stable. Hct, MCV, and MCHC were influenced by erythrocyte swelling. Differential count remained stable for 24 hr (22°C) and nearly 72 hr (4°C) except for monocytes. The overall performance of the Sysmex XT2000iV was excellent and compared favorably with that of the ADVIA 2120. A special strength was the excellent detection of feline eosinophils.

This study examines the application of a diode laser with a wavelength of 805 nm for periodontal treatment. While the use of the diode laser in this field has not been investigated so far, several authors have reported on the use of neodymium:yttrium-aluminum-garnet (Nd:YAG) laser for such applications. The aim of this study was to examine the immediate effect of the diode laser in reducing the bacterial concentration in periodontal pockets. Important periodontal indices (PBI, CPITN) were assessed in 50 patients to obtain initial values for a planned long-term study and to select appropriate periodontal pockets for this study. The periodontal pockets were required to have a minimum depth of 4 mm. Only proximal pockets were included in this study. The patients were subdivided into two groups. After microbiological samples had been collected with sterile paper tips, the group selected for laser treatment was subjected to scaling. One week after scaling, the patients underwent laser treatment. One week later, a second series of microbiological samples were obtained and the patients were subjected again to scaling; this time, however, they did not undergo laser treatment after 1 week. Two weeks after scaling, another series of microbiological samples was collected. The microbiological samples were evaluated to verify bacterial elimination from the periodontal pockets. A comparison between the initial and the final bacterial counts revealed that irradiation with the diode laser facilitates considerable bacterial elimination, especially of Actinobacillus actinomycetemcomitans, from periodontal pockets.

By using picosecond time-resolved photoluminescence we have measured the lifetime of excess charge carriers in GaN epitaxial layers grown on sapphire at temperatures up to 300 K. The decay time turns out to be dominated by trapping processes at low excitation levels. The radiative lifetime derived from our data is dominated by free excitons at temperatures below 150 K, but also clearly shows the gradual thermal dissociation of excitons at higher temperatures. From our data, we are able to determine the free exciton binding energy and the free carrier radiative recombination coefficient. By combining these data with optical absorption data, we find the interband momentum matrix element and an estimate for the hole effective mass, which is much larger than previously thought.

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