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X-ray microtomography (microCT) is becoming a valuable noninvasive tool for advancing our understanding of plant–water relations. Laboratory-based microCT systems are becoming more affordable and provide better access than synchrotron facilities. However, some systems come at the cost of comparably lower signal quality and spatial resolution than synchrotron facilities. In this study, we evaluated laboratory-based X-ray microCT imaging as a tool to nondestructively analyse hydraulic vulnerability to drought-induced embolism in a woody plant species. We analysed the vulnerability to drought-induced embolism of benchtop-dehydrated Eucalyptus camaldulensis plants using microCT and hydraulic flow measurements on the same sample material, allowing us to directly compare the two methods. Additionally, we developed a quantitative procedure to improve microCT image analysis at limited resolution and accurately measure vessel lumens. Hydraulic measurements matched closely with microCT imaging of the current-year growth ring, with similar hydraulic conductivity and loss of conductivity due to xylem embolism. Optimized thresholding of vessel lumens during image analysis, based on a physiologically meaningful parameter (theoretical conductivity), allowed us to overcome common potential constraints of some lab-based systems. Our results indicate that estimates of vulnerability to embolism provided by microCT visualization agree well with those obtained from hydraulic measurements on the same sample material.

Water acquisition is thought to be limited to the unsuberized surface located close to root tips. However, there are recurring periods when the unsuberized surfaces are limited in woody root systems, and radial water uptake across the bark of woody roots might play an important physiological role in hydraulic functioning. Using X-ray microcomputed tomography (microCT) and hydraulic conductivity measurements (Lp r), we examined water uptake capacity of suberized woody roots in vivo and in excised samples. Bark hydration in grapevine woody roots occurred quickly upon exposure to water (c. 4 h). Lp r measurements through the bark of woody roots showed that it is permeable to water and becomes more so upon wetting. After bark hydration, microCT analysis showed that absorbed water was utilized to remove embolism locally, where c. 20% of root xylem vessels refilled completely within 15 h. Embolism removal did not occur in control roots without water. Water uptake through the bark of woody roots probably plays an important role when unsuberized tissue is scarce/absent, and would be particularly relevant following large irrigation events or in late winter when soils are saturated, re-establishing hydraulic functionality before bud break.

Drought-induced xylem embolism is a serious threat to plant survival under future climate scenarios. Hence, accurate quantification of species-specific vulnerability to xylem embolism is a key to predict the impact of climate change on vegetation. Low-cost hydraulic measurements of embolism rate have been suggested to be prone to artefacts, thus requiring validation by direct visualization of the functional status of xylem conduits using nondestructive imaging techniques, such as X-ray microtomography (microCT). We measured the percentage loss of conductance (PLC) of excised stems of Laurus nobilis (laurel) dehydrated to different xylem pressures, and compared results with direct observation of gas-filled vs water-filled conduits at a synchrotron-based microCT facility using a phase contrast imaging modality. Theoretical PLC calculated on the basis of microCT observations in stems of laurel dehydrated to different xylem pressures overall were in agreement with hydraulic measurements, revealing that this species suffers a 50% loss of xylem hydraulic conductance at xylem pressures averaging −3.5 MPa. Our data support the validity of estimates of xylem vulnerability to embolism based on classical hydraulic techniques. We discuss possible causes of discrepancies between data gathered in this study and those of recent independent reports on laurel hydraulics.

Virtual histology is increasingly utilized to reconstruct the cell mechanisms underlying dental morphology for fragile fossils when physical thin sections are not permitted. Yet, the comparability of data derived from virtual and physical thin sections is rarely tested. Here, the results from archaeological human deciduous incisor physical sections are compared with virtual ones obtained by phase‐contrast synchrotron radiation computed microtomography (SRµCT) of intact specimens using a multi‐scale approach. Moreover, virtual prenatal daily enamel secretion rates are compared with those calculated from physical thin sections of the same tooth class from the same archaeological skeletal series. Results showed overall good visibility of the enamel microstructures in the virtual sections which are comparable to that of physical ones. The highest spatial resolution SRµCT setting (effective pixel size = 0.9 µm) produced daily secretion rates that matched those calculated from physical sections. Rates obtained using the lowest spatial resolution setup (effective pixel size = 2.0 µm) were higher than those obtained from physical sections. The results demonstrate that virtual histology can be applied to the investigated samples to obtain reliable and quantitative measurements of prenatal daily enamel secretion rates. The implementation of synchrotron radiation X‐ray microtomography for non‐destructive visualization of the dental prenatal enamel microstructure of intact archaeological human deciduous teeth is presented and compared with the physical thin‐sectioning of the same archaeological dental series. Prenatal daily enamel secretion rates, i.e. the distance between two adjacent daily enamel microstructures, have been measured with the two approaches. Results show a good agreement between physical and virtual histology.

The objective was to evaluate the effect of glide path and coronal flaring on the dentin volume removal and percentage of touched walls in curved canals using two heat-treated rotary files. The mesiobuccal canal of forty-eight, randomly selected, extracted mandibular molars was divided into two groups of 24 each, according to the type of instrument used (RACE EVO and EdgeSequel rotary files). Each group was further divided into three subgroups; Group (A): Control using one file shaped to 04/30, Group (B) with a glide path (EdgeGlidePath (EGP)), and Group (C): with a glide path and coronal flaring (EGP and EdgeTaper Platinum (ETP) SX file respectively). The root canals were then instrumented using the assigned instruments. The assessment was carried out using micro-CT. The comparison of the mean values of the tested groups about dentin volume removal and percentage of untouched walls did not reach statistical significance (p<0.05). Glide path and coronal flaring had an insignificant effect on the dentin volume removal and percentage of untouched walls in curved canals.

The purpose of this study was to evaluate the efficacy of different techniques in removing calcium silicate intracanal medicament (Bio-C Temp). Forty human single-canaled premolars were randomly distributed into five groups (n = 8). All root canals were instrumented, then filled with Bio-C Temp. Following 1-week incubation, the intra-canal medicament was removed using one of five techniques according to tooth group: conventional syringe irrigation, Endo Activator, passive ultrasonic irrigation (PUI), ProTaper Universal F3 and XP-endo Finisher (XPF). Micro-CT scanning was performed before and after removal of Bio-C Temp. All techniques significantly reduced the volume of Bio-C Temp (p < 0.001) without reaching complete elimination. The percentage of Bio-C Temp removed was significantly higher in the XPF group (98.2%) compared to conventional syringe irrigation (70.6%), the Endo Activator (75.7%), and the ProTaper Universal (76.6%). There was no significant difference between the XPF and PUI (95.1%) groups. None of the removal techniques were able to completely remove Bio-C Temp from the root canal. However, XPF was the most effective method, but was not statistically significant when compared to PUI. Clinical Relevance: This study demonstrated that both XPF and PUI outperform conventional irrigation in removing Bio-C Temp intracanal medicament.

ObjectivesThis in vitro study analysed potential of early proximal caries detection using 3D range data of teeth consisting of near-infrared reflection images at 850 nm (NIRR).Materials and methodsTwo hundred fifty healthy and carious permanent human teeth were arranged pairwise, examined with bitewing radiography (BWR) and NIRR and validated with micro-computed tomography. NIRR findings were evaluated from buccal, lingual and occlusal (trilateral) views according to yes/no decisions about presence of caries. Reliability assessments included kappa statistics and revealed high agreement for both methods. Statistical analysis included cross tabulation and calculation of sensitivity, specificity and AUC.ResultsUnderestimation of caries was 24.8% for NIRR and 26.4% for BWR. Overestimation was 10.4% for occlusal NIRR and 0% for BWR. Trilateral NIRR had overall accuracy of 64.8%, overestimation of 15.6% and underestimation of 19.6%. NIRR and BWR showed high specificity and low sensitivity for proximal caries detection.ConclusionsNIRR achieved diagnostic results comparable to BWR. Trilateral NIRR assessments overestimated presence of proximal caries, revealing stronger sensitivity for initial caries detection than BWR.Clinical relevanceNIRR provided valid complement to BWR as diagnostic instrument. Investigation from multiple angles did not substantially improve proximal caries detection with NIRR.

Although many ureteral stents are commercially available, the actuality of encrustation is yet to be elucidated in humans. This study compared the Tria Ureteral Stent with PercuShield and the Polaris Ultra Ureteral Stent with HydroPlus Coating for short-term encrustation formation. Eighty-four patients, who required ureteral stent placement after ureteroscopy, were randomized into two stent groups. After stent removal on postoperative day 14, the encrustation volume on the stent surface was measured by micro-computed tomography. The primary outcome was the inner luminal encrustation volume. Secondary outcomes were encrustation volume on the outer or total surfaces and occurrence of adverse events. Clinical factors related to encrustation were also assessed as a post-hoc analysis. Finally, of the 82 patients analyzed, 75 (91.5%) had encrustation in the inner lumen of the stent. The difference in median inner encrustation volume between the Tria and Polaris Ultra stents was comparable (0.56 vs. 0.37 mm 3 , P  = 0.183). There was no difference observed in the encrustation volume on the outer/total surfaces and stent-related adverse events. In both ureteral stents, the shaft body showed significant inner luminal encrustation compared to the proximal or distal loop (all, P  < 0.05). Dyslipidemia ( P  = 0.027), elevated urine pH ( P  = 0.046), and crystalluria ( P  = 0.010) were associated with encrustation formation. The Tria and Polaris Ultra stents had similar efficacy for preventing encrustation in the short-term. Further studies are required to compare their long-term patency.

ObjectivesThis study compared canal transportation and centering ratio produced after instrumentation with a single heat-treated reciprocating system, WaveOne Gold (WOG; Dentsply Sirona, Tulsa, OK, USA) and a single heat-treated rotary instrument, XP-endo Shaper (XPS; FKG, La Chaux-de-Fonds, Switzerland), using micro-computed tomographic (micro-CT) imaging, and evaluated the ability of double-digital radiography (DDR) to detect canal transportation.Materials and methodsMesial root canals of mandibular molars with severe curvature (25–70°) were randomly assigned to either WOG or XPS groups for preparation. Centering ratio was measured by micro-CT imaging, while canal transportation was measured by micro-CT and DDR methods at 3, 5, and 7 mm from the apex. Data were statistically compared between groups using the t test (α = 5%).ResultsThe micro-CT method showed that XPS’s shaping ability regarding the centering ability (P = 0.030) and canal transportation (P = 0.028) was significantly better than WOG only at the 7-mm level. The DDR technique detected no difference in canal transportation between groups at any level (P > 0.05); however, a significant difference between evaluation methods was detected at the 5-mm level in the WOG group (P = 0.023).ConclusionsMicro-CT technique revealed a significantly better centering ability and less canal transportation with XPS compared to WOG. The DDR technique was not capable of detecting the significant difference between the tested groups.Clinical relevanceRoot canal curvatures may lead to procedural errors during endodontic treatment. Thus, differences on the shaping ability of single heat-treated reciprocating and rotary systems should be known.

Background Proximal caries datasets for training artificial intelligence (AI) algorithms commonly include clinician-annotated radiographs. These conventional annotations are susceptible to observer variability, and early caries may be missed. Micro-computed tomography (CT), while not feasible in clinical applications, offers a more accurate imaging modality to support the creation of a reference-standard dataset for caries annotations. Herein, we present the Academic Center for Dentistry Amsterdam—Diagnostic Insights for Radiographic Early-caries with micro-CT (ACTA-DIRECT) dataset, which is the first dataset pairing dental radiographs and micro-CT scans to enable higher-quality annotations. Methods The ACTA-DIRECT dataset encompasses 179 paired micro-CT scans and radiographs of early proximal carious teeth, along with three types of annotations: conventional annotations on radiographs, micro-CT-assisted annotations on radiographs, and micro-CT annotations (reference standard). Three dentists independently annotated proximal caries on radiographs, both with and without micro-CT assistance, enabling determinations of interobserver agreement and diagnostic accuracy. To establish a reference standard, one dental radiologist annotated all caries on the related micro-CT scans. Results Micro-CT support improved interobserver agreement (Cohen’s Kappa), averaging 0.64 (95% confidence interval [CI]: 0.59–0.68) versus 0.46 (95% CI: 0.44–0.48) in its absence. Likewise, average sensitivity and specificity increased from 42% (95% CI: 34–51%) to 63% (95% CI: 54–71%) and from 92% (95% CI: 88–95%) to 95% (95% CI: 92–97%), respectively. Conclusion The ACTA-DIRECT dataset offers high-quality images and annotations to support AI-based early caries diagnostics for training and validation. This study underscores the benefits of incorporating micro-CT scans in lesion assessments, providing enhanced precision and reliability. Graphical Abstract