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Endodontic treatment with subsequent restoration of 3 immature incisors with horizontal fractures in the cervical region is described. In I tooth the fracture occurred supragingivally, whereas in 2 others the fracture was such that the root margins were between 1 and 2 mm subosseous. In these teeth proper access to the roots was established by means of orthodontic extrusion and/or periodontal surgery. After endodontic treatment, the gutta-percha was removed from the root canals to a level 2 to 3 mm apically to the osseous crest. The root canal dentin was acid-etched and a post to retain a crown was cemented into the canal with a composite resin. The resin will then penetrate into the dentinal tubules of the root canal walls and strengthen the root to such a degree that it becomes restorable. Semipermanent composite resin crowns and, in one instance, a more permanent porcelain crown were used to restore the teeth. [ABSTRACT FROM AUTHOR]

In 2023 the wind industry hit a milestone of one terawatt of installed capacity globally. That amount is expected to double within the next decade as billions of dollars are invested in new wind projects annually. Wildlife mortality is a primary concern regarding the proliferation of wind power, and many studies have investigated bird and bat interactions. Little is known about the interactions between wind turbines and insects, despite these animals composing far more biomass than vertebrates. Turbine placement, coloration, shape, heat output, and lighting may attract insects to turbines. Insects attract insectivorous animals, which may be killed by the turbines. Compiling current knowledge about these interactions and identifying gaps in knowledge is critical as wind power grows rapidly. We reviewed the state of the literature investigating insects and wind energy facilities, and evaluated hypotheses regarding insect attraction to turbines. We found evidence of insect attraction due to turbine location, paint color, shape, and temperature output. We provide empirical data on insect abundance and richness near turbines and introduce a risk assessment tool for comparing wind development with suitable climate for insects of concern. This understudied topic merits further investigation as insects decline globally. Compiling information will provide a resource for mitigation and management strategies, and will inform conservation agencies on what insects may be most vulnerable to the expansion of wind technologies., Competing Interests: The authors declare that they have no competing interests., (© 2024 Weschler and Tronstad.)

Aquatic invertebrates are excellent indicators of ecosystem quality; however, choosing a sampling method can be difficult. Each method and associated protocol has advantages and disadvantages, and finding the approach that minimizes biases yet fulfills management objectives is crucial. To test the effects of both sampling methods and sample handling-i.e., to composite samples or leave them as replicates-we collected aquatic invertebrates from the Niobrara River at Agate Fossil Beds National Monument, Nebraska, using three methods and two sample handling protocols. We compared aquatic invertebrate assemblages collected with a Hester-Dendy multi-plate sampler, Hess sampler, and a D-frame dipnet. We calculated six common bioassessment metrics from composite (combined) and replicate (separate) samples. Hess samples contained the highest taxonomic richness (capturing 77% of all taxa observed) and dipnet samples the least (47%). Hester-Dendy samples had the greatest proportion of Ephemeroptera, and Ephemeroptera, Plecoptera, and Trichoptera (EPT). Dipnet samples had the lowest evenness values. In terms of sample handling, composite samples had inflated richness, diversity, and evenness compared with replicate samples, but bioassessment metrics calculated from proportions or averages (i.e., Hilsenhoff's Biotic Index and the proportion of EPT taxa) did not differ between them. The proportion of invertebrate groups from composite samples were not statistically different among sampling methods, but several groups differed between replicate samples collected by different methods. Ultimately, we recommend collecting replicate samples with a Hess sampler when the goal of the study is to detect ecosystem change, among locations or differences in variables of interest.

Background: Aortic aneurysms are common vascular conditions that cause considerable morbidity and mortality. Understanding of the mechanisms involved in the pathogenesis of the condition remains limited. Recently, infection has been suggested as possible contributor in the development of the disease. The aim of the present study was to examine aortic aneurysms for the presence of bacterial DNA using polymerase chain reaction (PCR) targeting the 16S ribosomal RNA (rRNA) gene, followed by cloning and sequencing., Methods: Universal eubacterial primers were used to amplify 16S rRNA bacterial genes in 10 specimens from arterial walls of aortic aneurysms. Subsequently, PCR amplicons were cloned into Escherichia coli and sequencing of the cloned inserts was used to determine species identity or closest relatives by comparison with known sequences in GenBank., Results: Sequences of Stenotrophomonas spp., including S. maltophilia (formerly Pseudomonas homology group V) were detected in six aneurysm samples. Propionibacterium acnes was identified in five samples, and Brevundimonas diminuta (formerly P. diminuta) in four samples. Other species previously assigned to the Pseudomonas genus such as Comamonas testosteroni, Delftia acidovorans, Burkholderia cepacia, Herbaspirillum sp., and Acidovorax sp. were also detected. Some clones fell into other environmental species, including Methylobacterium sp. and Bradyrhizobium elkanii, and others represented bacteria that have not yet been cultivated. DNA sequences from oral bacteria, including Streptococcus sanguinis, Tannerella forsythia, and Leptotrichia buccalis were detected. Sequences from Prevotella melaninogenica and Lactobacillus delbrueckii, which are commonly found in both mouth and gastrointestinal tract, were also detected. Additional species included Dermacoccus spp. and Corynebacterium vitaeruminis., Conclusions: A wide variety of bacteria, including oral bacteria, was found to colonize aortic aneurysms and may play a role in their development. Several of these microorganisms have not yet been cultivated., Clinical Relevance: Although Chlamydophila pneumoniae has been detected in aneurysmal walls, its exact role in the condition remains inconclusive. Overall, there is scarce information about the role of microorganisms in aneurysmal disease. In the present study, we used molecular genetics to detect a diversity of bacteria in arterial walls of aortic aneurysms. The presence of multiple microorganisms in aneurysmal disease may have implications for chemoprophylaxis and antibiotic treatment if directed only at C.pneumoniae.

Background: Aortic aneurysms affect an increasing number of elderly patients and cause considerable morbidity and mortality. The understanding of the mechanisms involved in the pathogenesis of aortic aneurysms is unclear and little is known about the role of microorganisms in the development of the condition. The aim of the present study was to examine aortic aneurysm samples for the presence of four putative periodontal pathogens: Actinobacillus actinomycetemcomitans, Treponema denticola, Tannerella forsythensis, and Porphyromonas gingivalis., Methods: Fifty-six samples from the aneurysm wall were obtained from patients undergoing aneurysm repair. DNA was extracted from tissue by conventional methods. Universal eubacterial primers for general detection of bacteria and species specific primers for detection of the periodontal pathogens were used to amplify part of the 16S rRNA gene by polymerase chain reaction (PCR)., Results: Bacterial DNA was detected in 50 of the 56 aneurysm samples (89.2%). A. actinomycetemcomitans was found in four samples (7.1%). None of the samples was positive for T. denticola, T. forsythensis, or P. gingivalis., Conclusion: Bacteria are commonly present in aortic aneurysms and may play a role in the development of the condition. Periodontal pathogens are also present.

Background: There have been a number of reports of brain abscesses suggesting an odontogenic etiology. However, no efforts have been made to compare brain abscess isolates with isolates from the oral cavity using highly discriminative methods. We report a brain abscess caused by Streptococcus constellatus in an immunocompromised patient where oral infection (periodontitis) was suspected to be implicated., Methods: The brain abscess and oral isolates were compared by means of one phenotypic and three genetic (restriction fragment length polymorphism [RFLP], ribotyping, and random amplified polymorphic DNA [RAPD]) fingerprinting techniques., Results: The phenotypic method and RFLP showed identical profiles between brain and periodontal isolates, while ribotyping and RAPD showed very close similarity, with only one band difference in one of the three ribotypes and in one of the three polymorphic RAPD., Conclusions: Gene transfer by genetic recombinational events in the periodontal pocket might have been responsible for the emergence of a strain variant of S. constellatus that had the potential to cause an abscess at a distant site (brain). The importance of odontogenic sources as potential foci of infection for brain abscesses is discussed.

Objective: The purpose of the present study was to reexamine the possibility that bacteria, particularly anaerobes, are present in aortic aneurysms., Methods: From December 2000 to November 2001, 53 samples from aneurysm walls were collected from 49 patients during reconstructive surgery. The tissue specimens were sectioned and cultured under anaerobic conditions. Twenty-eight specimens were also subjected to scanning or transmission electron microscopy., Results: Anaerobic cultivation yielded bacteria in 14 of the 53 samples (26.4%). All bacteria were gram-positive cocci or rods from nine genera and 12 species. Five cultures (35%) were mixed, containing two bacterial species. Mixed aerobic and anaerobic species were found in four samples (28.5%). Anaerobic bacteria were recovered from 10 of 14 positive cultures (71%). Among anaerobes found were Propionibacterium acnes, Propionibacterium granulosum, Actinomyces viscosus, Actinomyces naeslundii, and Eggerthella lenta. Coaggregating bacteria of different sizes and structure were found on the aneurysm walls and inside the intravascular plaque at electron microscopy. Bacteria were found in 20 of the 28 samples (71%) examined with scanning or transmission electron microscopy., Conclusion: Multiple bacteria, many of which did not belong to the indigenous skin microflora, colonize aortic aneurysms. It is not clear whether the bacteria contribute to weakening of the aortic wall by eliciting inflammation or whether they are secondary colonizers of aneurysms.

Whether micro-organisms can live in periapical endodontic lesions of asymptomatic teeth is under debate. The aim of the present study was to visualize and identify micro-organisms within periapical lesions directly, using fluorescence in situ hybridization (FISH) in combination with epifluorescence and confocal laser scanning microscopy (CLSM). Thirty-nine periapical lesions were surgically removed, fixed, embedded in cold polymerizing resin and sectioned. The probe EUB 338, specific for the domain Bacteria, was used together with a number of species-specific 16S rRNA-directed oligonucleotide probes to identify bacteria. To control non-specific binding of EUB 338, probe NON 338 was used. Alternatively, DAPI (4',6'-diamidino-2-phenylindole) staining was applied to record prokaryotic and eukaryotic DNA in the specimens. Hybridization with NON 338 gave no signals despite background fluorescence of the tissue. The eubacterial probe showed bacteria of different morphotypes in 50 % of the lesions. Rods, spirochaetes and cocci were spread out in areas of the tissue while other parts seemed bacteria-free. Bacteria were also seen to co-aggregate inside the tissue, forming microcolonies. Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythensis and treponemes of phylogenetic Group I were detected with specific probes. In addition, colonies with Streptococcus spp. were seen in some lesions. A number of morphotypes occurred that could not be identified with the specific probes used, indicating the presence of additional bacterial species. CLSM confirmed that bacteria were located in different layers of the tissue. Accordingly, the FISH technique demonstrated mixed consortia of bacteria consisting of rods, spirochaetes and cocci in asymptomatic periapical lesions of root-filled teeth.

The periapical microbiota of 36 teeth with refractory apical periodontitis was investigated. None of the teeth had responded to conventional endodontic or long-term (> 6 months), calcium-hydroxide treatment. Eight patients had received antibiotics systemically. After anaerobic culture, a total of 148 microbial strains were detected among 67 microbial species. One of the 36 lesions was culture-negative. Approximately half (51.0%) of the bacterial strains were anaerobic. Gram-positive species constituted 79.5% of the flora. Facultative organisms, such as Staphylococcus, Enterococcus, Enterobacter, Pseudomonas, Stenotrophomonas, Sphingomonas, Bacillus, or Candida species were recovered from 27 of the lesions (75%). Sulfur granules were found in 9 lesions (25%). In these granules Actinomyces israelii, A. viscosus, A. naeslundii, and A. meyeri were identified. Other bacterial species, both gram-positive and gram-negative, were detected in the granules as well. Two sulfur granules did not contain Actinomyces. Scanning electron microscopy demonstrated rod- and spirochete-like cells in the granules, and transmission electron microscopy revealed organisms with copious amounts of extracellular material. Outer membrane vesicles were also seen. Some of the granules were calcified. This study demonstrated a wide variety of microorganisms, particularly gram-positive ones, in the periapical lesions of teeth with refractory apical periodontitis.