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Objective: To compare the agreement of images in white light (WL), fluorescence (FL), and digital radiographs (DR), on the diagnosis and treatment decisions for occlusal caries lesions against a micro-CT gold standard. Material and Methods: Ten extracted third molars, with enamel and/or dentin caries (ICDAS 2-4), were included. Occlusal surface images were acquired with an intraoral camera (SoproLife®) in WL and FL modes. DR was obtained using an intraoral X-ray and a semi-direct digital system. A total of 780 images were needed, organized in a template, to be later examined by twenty-six dentists invited to compose the study. The Generalized Estimation Equations model was used to compare the proportions of the correct answers between the three methods and the gold standard. When significant, Bonferroni post-hoc test was used to identify differences (α=5%). Results: Most of the examiners were specialists (76.9%) with 14.5 years of experience. All diagnostic methods were similar and showed low agreement (DR 12.7%, WL 16.5%, and FL 16.5%) compared with gold standard caries diagnostic scores. Regarding treatment decisions, mean agreement for all diagnostic methods was higher (43.2%; p<0.001), and among all methods, WL (48.1%) and FL (51.2%) modes performed better than DR (30.4%, p<0.001). Conclusion: SoproLife® images could help clinicians to propose rational, minimally invasive treatments for occlusal caries lesions. [ABSTRACT FROM AUTHOR]

Brachycephalus is a small, endemic genus of anurans that occur throughout the Brazilian Atlantic Forest. Recent analyses corroborated the monophyly of two species groups within this genus (B. ephippium and B. pernix), whereas the B. didactylus group appears to be polyphyletic. Herein, we compare and describe the skeletal system of all species from the Brachycephalus ephippium species group. We investigated diagnostic characters that are potentially useful to delimit similar species, confirmed the previously proposed genus definition and added six extra characters. We propose an osteological diagnosis for each species of the B. ephippium group, evaluating and describing intraspecific variations. Our results suggest that adults of B. ephippium group have ornamented parotic plates, ornamented post‐orbital crests, absence of quadratojugal and neopalatines, distal end of the otic ramus of squamosal expanded towards the parotic plate, reduced zygomatic ramus of the squamosals, posterolateral projection of the crista parotica, presence of ornamented spinal plates (except B. alipioi) and ornamented paravertebral plates. We highlighted the importance of including more than one specimen per species when dealing with miniaturized taxa. A comparison with other Brachycephalus species groups and with Ischnocnema was also provided. Lastly, we suggest some characters to be included in future phylogenetic analysis. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the efficacy of silver diamine fluoride (SDF) in arresting dentin caries lesions when applied under different concentrations and times. Material and Methods: Forty-two bovine blocks were selected and fixed in 24-well plates. Each well received a mixed bacterial inoculum added to the culture medium with 5% sucrose. The plates were incubated in microaerophilia (7 days) for caries formation, confirmed by micro-CT (M1). SDF was applied over the carious lesions for different times and concentrations (n=6): SDF 30% - immediate removal, 1 minute and 3 minutes; SDF 38%, - immediate removal, 1 minute and 3 minutes. The group without treatment was the control. Then, the samples were again scanned by micro-CT (M2) and submitted to a second cariogenic challenge for 21 days. Then, a final scan was performed (M3). Results: Mean pH at the culture medium and lesion depth were compared using Kruskal-Wallis and Wilcoxon tests. 38% SDF showed the lowest metabolic activity of the biofilm. All 38% groups and 30% 1 and 3 minutes did not show an increase in mean lesion depth comparing M3 with M1. However, only 30% 3 minutes and 38% 1 and 3 minutes showed a significant reduction of lesion depth. Conclusion: The minimum application time of 30% SDF to arrest dentin caries lesion was 1 minute, while 38% SDF arrested with application and immediate removal. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to evaluate, by micro-computed tomography (micro-CT) analysis, the remaining filling material during endodontic retreatment performed with Protaper retreatment without solvent. Methods: Forty mandibular molars were divided into two groups (n = 20) according to the sealer used in the obturation: the bioceramic TotalFill BC (TF) or the resin-based AH Plus (AHP). The specimens were scanned before instrumentation, after obturation and after filling removal. Only the mesial roots were analysed. The filling volumes and the remaining filling material were calculated in the entire root canal and in the cervical, middle and apical thirds. Results: The volume of obturation and the volume of remaining filling material in the entire root canal and in the cervical, middle and apical thirds of the canal between the groups were not statistically different (independent t-test, p > 0.05). In the AHP group, there was a higher percentage of remaining filling material in the middle third than in the cervical third (p < 0.05). Conclusion: The filling material could not be entirely removed from any specimen. [ABSTRACT FROM AUTHOR]

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Introduction: This study evaluated the removal of the filling material during endodontic retreatment considering the presence of cracks and the dentin age. Methods and Materials: A total of 20 freshly extracted single-rooted teeth were categorized into the following two groups according to the age of the patients: Group Young (Y; aged 18-30 years) and Group Old (O; aged )60 years). Each tooth specimen was scanned by microcomputed tomography (micro-CT) subsequently after endodontic retreatment with the Reciproc instruments (REC). The images were analyzed for differences in the volume of dentin cracks and the presence of the filling material in the middle and apical thirds of the teeth among the groups, according to the dentin age. Results: The micro- CT images showed that after retreatment, there were more cracks in the old root dentin than those in the young root dentin, although the difference was not statistically significant (P>0.05). The greatest reduction in the filling material was achieved when the old root dentin with cracks was retreated when compared with that of the young root dentin with cracks, but the difference was not statistically significant (P>0.05). Conclusion: The dentinal age and the presence of cracks were not found to be relevant factors for the removal of the filling material. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the efficacy of a 37% phosphoric acid solution delivered by conventional irrigation, Endovac®, sonic and ultrasonic activated tips and plastic file on Ca(OH)2 removal using micro-CT. Methods: Fifty mesial roots of mandibular molars were manually instrumented. Ca(OH)2 paste was inserted into the root canal system with a 25 K-file. All teeth were scanned by micro-CT to determine the initial dressing volume. After 7 days, the Ca(OH)2 was removed with a 25 K-file and 10 mL of NaOCl. The specimens were allocated in 5 groups irrigated with phosphoric acid (n = 10): conventional irrigation (CI); Endovac (EV); Sonic irrigation (SI); Passive ultrasonic irrigation (PUI) and Plastic file (PF). The teeth were re-scanned by micro-CT. Results: The percentage volume of Ca(OH)2 removal was calculated. Data was evaluated by Kruskal-Wallis, Mann-Whitney and Wilcoxon tests (p < 0.05). PUI removed significantly more Ca(OH)2 than CI, EV and PF. Clinical Significance: The use of 37% phosphoric acid associated with PUI or SI showed a better performance on Ca(OH)2 removal compared with other agitation systems. [ABSTRACT FROM AUTHOR]

Introduction This study aimed to evaluate the frequency of dentinal microcracks observed after root canal preparation with 2 reciprocating and a conventional full-sequence rotary system using micro-computed tomographic analysis. Methods Thirty mesial roots of mandibular molars presenting a type II Vertucci canal configuration were scanned at an isotropic resolution of 14.16 µm. The sample was randomly assigned to 3 experimental groups (n = 10) according to the system used for the root canal preparation: group A-Reciproc (VDW, Munich, Germany), group B-WaveOne (Dentsply Maillefer, Baillagues, Switzerland), and group C-BioRaCe (FKG Dentaire, La-Chaux-de-Fonds, Switzerland). Second and third scans were taken after the root canals were prepared with instruments sizes 25 and 40, respectively. Then, pre- and postoperative cross-section images of the roots (N = 65,340) were screened to identify the presence of dentinal defects. Results Dentinal microcracks were observed in 8.72% (n = 5697), 11.01% (n = 7197), and 7.91% (n = 5169) of the cross-sections from groups A (Reciproc), B (WaveOne), and C (BioRaCe), respectively. All dentinal defects identified in the postoperative cross-sections were also observed in the corresponding preoperative images. Conclusions No causal relationship between dentinal microcrack formation and canal preparation procedures with Reciproc, WaveOne, and BioRaCe systems was observed. [ABSTRACT FROM AUTHOR]

Digital radiography in the inspection of welded pipes to be installed under deep water offshore gas and oil pipelines, like a presalt in Brazil, in the paper has been investigated. The aim is to use digital radiography for nondestructive testing of welds as it is already in use in the medical, aerospace, security, automotive, and petrochemical sectors. Among the current options, the DDA (Digital Detector Array) is considered as one of the best solutions to replace industrial films, as well as to increase the sensitivity to reduce the inspection cycle time. This paper shows the results of this new technique, comparing it to radiography with industrial films systems. In this paper, 20 test specimens of longitudinal welded pipe joints, specially prepared with artificial defects like cracks, lack of fusion, lack of penetration, and porosities and slag inclusions with varying dimensions and in 06 different base metal wall thicknesses, were tested and a comparison of the techniques was made. These experiments verified the purposed rules for parameter definitions and selections to control the required digital radiographic image quality as described in the draft international standard ISO/DIS 10893-7. This draft is first standard establishing the parameters for digital radiography on weld seam of welded steel pipes for pressure purposes to be used on gas and oil pipelines. [ABSTRACT FROM AUTHOR]

Considering that the risks associated with ionising radiation are dependent on the characteristics of the exposed individual and that the structures and sizes of the human body vary considerably as a function of gender, efforts must be made in order to study the effective and absorbed doses in thoracic radiological examinations, taking into account the special features of the female anatomy. In this work, the Monte Carlo code Monte Carlo N-Particle eXtended (MCNPX) and the Female Adult voXel (FAX) phantom are combined in order to investigate how the effective and absorbed doses vary in thoracic radiological examinations. The results suggest that different precautionary measures should be taken depending on the chosen geometric projection and that the application of higher voltages to the X-ray tube appears to be an alternative to reduce the effective and absorbed doses. [ABSTRACT FROM AUTHOR]