364 research outputs found
A new improved protocol for in vitro intratubular dentinal bacterial contamination for antimicrobial endodontic tests: standardization and validation by confocal laser scanning microscopy
Objectives To compare three methods of intratubular contamination that simulate endodontic infections using confocal laser scanning microscopy (CLSM). Material and Methods Two pre-existing models of dentinal contamination were used to induce intratubular infection (groups A and B). These methods were modified in an attempt to improve the model (group C). Among the modifications it may be included: specimen contamination for five days, ultrasonic bath with BHI broth after specimen sterilization, use of E. faecalisduring the exponential growth phase, greater concentration of inoculum, and two cycles of centrifugation on alternate days with changes of culture media. All specimens were longitudinally sectioned and stained with of LIVE/DEAD® for 20 min. Specimens were assessed using CLSM, which provided images of the depth of viable bacterial proliferation inside the dentinal tubules. Additionally, three examiners used scores to classify the CLSM images according to the following parameters: homogeneity, density, and depth of the bacterial contamination inside the dentinal tubules. Kruskal-Wallis and Dunn’s tests were used to evaluate the live and dead cells rates, and the scores obtained. Results The contamination scores revealed higher contamination levels in group C when compared with groups A and B (p;0.05). The volume of live cells in group C was higher than in groups A and B (
Idiopathic Osteosclerosis of the Jaw in a Brazilian Population: a Retrospective Study
Svrha: Željelo se opisati slučajeve idiopatske osteoskleroze (IO), pripremiti pregled literature o istoj tematici te analizirati glavna svojstva, dijagnoze, diferencijalne dijagnoze i načine liječenja. Materijali i metode: Retrospektivno su analizirana 354 ortopantomograma u potrazi za veličinom, oblikom i lokacijom IO-a te demografske karakteristike pacijenta. Pregled literature u bazama
Medline i Lilacs temeljio se na sintagmama idiopatska osteoskleroza, skleroza kosti, otočići guste kosti i čeljusti. Rezultati: Idiopatska osteoskleroza pronađena je na 5,6 posto ortopantomograma (n = 20 pacijenata, 22 fokusa). Pacijenti su bili zdravi, u dobi od 5 do 51 godine (srednja vrijednost = 29,8 godina), a omjer između muškaraca i žena iznosio je 3 : 2. OI je uglavnom uočen u premolarnoj/molarnoj regiji u području apeksa korijena, između korijena, udaljen od zuba, lateralno od zuba te u bezubim područjima. Distribucija između desne i lijeve strane čeljusti bila je podjednaka za svih 22 fokusa, a samo jedan slučaj otkriven je u maksili. IO je dobro lokaliziran i definiran, radioopaktan i uglavnom okrugao ili ovoidan te katkad iregularnog oblika. U nekim slučajevima sliči kondenzirajućem ostitisu, ali diferencijalna dijagnoza može uključivati kompleksni odontom, fokalnu cementnokoštanu displaziju ili zaostatni korijen. O toj je temi pregledano dvadeset istraživanja. Zaključak: Pojavnost IO-a u brazilskoj populaciji iznosi 5,6 posto, raspon godina tijekom istraživanja bio je od 5 do 51 (srednja vrijednost = 29,8), a omjer između muških i ženskih sudionika iznosio je 3 : 2. Radioopaktne lezije uočene su na različitim lokacijama, no najčešće u mandibuli. Ovi rezultati i pregled literature potkrjepljuju hipotezu o idiopatskoj osteosklerozi kao o posljedici varijacije u razvoju normalne kosti, što ne zahtijeva liječenje.Objectives: To report cases of idiopathic osteosclerosis (IO), to review the literature on the subject, and to discuss its main characteristics, diagnosis, differential diagnosis, and treatment. Material and methods: Retrospective analysis of 354 panoramic radiographs, searching for IO, its size, shape, location, and noting patients’ demographic information. Literature review used Medline and Lilacs databases and the terms idiopathic osteosclerosis OR bone sclerosis OR dense bone island AND jaws. Results: IO was identified in 5.6% of the radiographs (n=20 patients, 22 foci). Patients were healthy, with an age ranging from 5 to 51 years (mean=29.8), with male-female ratio of 3:2. IOs were found mainly in the premolar/molar region, at root apices, between roots, away from the teeth, laterally to the tooth, and in edentulous areas. The distribution between right and left sides of the jaw was equal for the 22 foci, with only one case in the maxilla. IOs were localized, well-defined, radiopaque, mostly round or ovoid in shape, but sometimes irregular.
In some cases, IOs were similar to condensing osteitis, but differential diagnosis also considered complex odontoma, focal cemento-osseous dysplasia, and residual roots. Twenty studies on the topic were reviewed. Conclusions: Incidence of IO in the Brazilian sample was 5.6%, with age ranging from 5 to 51 years (mean=29.8), and male-female ratio of 3:2. The radiopacities occurred in different locations, with significant prevalence in the mandible. The findings and the literature review corroborate the hypothesis that IO should be considered developmental variation of normal bone that does not require treatment
Influence of NiTi alloy on the root canal shaping capabilities of the ProTaper Universal and ProTaper Gold rotary instrument systems
A new improved protocol for in vitro intratubular dentinal bacterial contamination for antimicrobial endodontic tests: standardization and validation by confocal laser scanning microscopy
TRY plant trait database – enhanced coverage and open access
Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives
Limitation of diagnostic value of cone-beam CT in detecting apical root isthmuses
Isthmuses are reported as common anatomic complexities in teeth often associated with failures in endodontic treatment. They should be considered before starting treatment and a preoperative computed tomography scan (CT) may demonstrate these complexities. Objective: To assess the diagnostic value of the highest resolution settings of a cone-beam CT (CBCT) system in identifying and measuring apical isthmuses, using micro-CT as reference. Methodology: After micro-CT scanning, 40 humans’ lower first molars with isthmuses in the apical-3 mm of mesial roots were scanned by the highest resolution settings of the New Generation i-Cat ® CBCT equipment. Two blinded observers recorded the detection of isthmuses in CBCT scans. The lengths of isthmuses were compared between micro-CT and CBCT to assess the diagnostic value of CBCT. Quantitative data for sensitivity were represented as percentages (95% confidence interval). The Bland-Altman method was used to assess differences between gold standard lengths (micro-CT) and CBCT lengths. Results: BCT demonstrated 30 positive findings, representing sensitivity for isthmus identification of 75% (95% CI=0.4114–1.1364). Differences between the lengths in micro-CT (1.99±0.40 mm) and CBCT (1.53±0.41 mm) were significant (p<0.0001). Conclusion: The CBCT device used presented limited diagnostic value in the identification and measurement of apical isthmuses in the mesial roots of lower molars. In some cases, the actual anatomy of the apical root canal may not be completely delineated in this type of CBCT system, even using the highest resolution settings
Apical adaptation, sealing ability and push-out bond strength of five root-end filling materials
This study compared the fluid filtration, adaptation to the root canal walls, and the push-out bond strength of two resin-based sealers and three calcium silicate-based retrograde filling materials. Fifty maxillary canines were shaped using manual instruments and the apical portion was sectioned. Retrograde cavities of 3-mm depth were prepared. The specimens were divided into five groups (n = 10): Sealer 26 (S26); MBPc (experimental); MTA; Portland cement with 20% zirconium oxide (PC/ZO), and Portland cement with 20% calcium tungstate (PC/CT). The fluid filtration was measured at 7 and 15 days. To evaluate the interfacial adaptation, sections of the teeth, 1 and 2 mm from the apex, were prepared and the percentage of gaps was calculated. The push-out bond strength at 2 mm from the apex was evaluated. Statistical analysis was performed using the ANOVA/Tukey’s test (p < 0.05). At 7 and 15 days (p = 0.0048, p = 0.006), the PC/CT group showed higher fluid filtration values when compared to other groups. At 1 mm from the apex, no statistical differences in the adaptation were found among the cements (p = 0.44). At 2 mm from the apex, the PC/ZO group presented statistically lower percentage of gaps than S26, MBPc, and MTA (p = 0.0007). The MBPc group showed higher push-out bond strength than other cements evaluated (p = 0.0008). The fluid filtration and interfacial adaptation of the calcium silicate-based cements were similar to those of the resin-based cements. The resinous cement MBPc showed superior push-out bond strength
Idiopathic Osteosclerosis of the Jaw in a Brazilian Population: a Retrospective Study
Objectives: To report cases of idiopathic osteosclerosis (IO), to review the literature on the subject, and to discuss its main characteristics, diagnosis, differential diagnosis, and treatment. Material and methods: Retrospective analysis of 354 panoramic radiographs, searching for IO, its size, shape, location, and noting patients’ demographic information. Literature review used Medline and Lilacs databases and the terms idiopathic osteosclerosis OR bone sclerosis OR dense bone island AND jaws. Results: IO was identified in 5.6% of the radiographs (n=20 patients, 22 foci). Patients were healthy, with an age ranging from 5 to 51 years (mean=29.8), with male-female ratio of 3:2. IOs were found mainly in the premolar/molar region, at root apices, between roots, away from the teeth, laterally to the tooth, and in edentulous areas. The distribution between right and left sides of the jaw was equal for the 22 foci, with only one case in the maxilla. IOs were localized, well-defined, radiopaque, mostly round or ovoid in shape, but sometimes irregular.
In some cases, IOs were similar to condensing osteitis, but differential diagnosis also considered complex odontoma, focal cemento-osseous dysplasia, and residual roots. Twenty studies on the topic were reviewed. Conclusions: Incidence of IO in the Brazilian sample was 5.6%, with age ranging from 5 to 51 years (mean=29.8), and male-female ratio of 3:2. The radiopacities occurred in different locations, with significant prevalence in the mandible. The findings and the literature review corroborate the hypothesis that IO should be considered developmental variation of normal bone that does not require treatment
Prevalencia de alteraciones en el complejo estilohiodeo en radiografías panorámicas digitales
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