Search Results (38)

This essay theorizes the body-land, a living site where colonial violence, displacement, and resurgence converge through a hemispheric dialogue between Indigenous and decolonial feminisms from Abya Yala and Turtle Island. Drawing on Lorena Cabnal’s concept of the body-land as the primary terrain of colonial invasion and regeneration, María Lugones’s analysis of the coloniality of gender as a system that fractures body, land, and relations, Leanne Betasamosake Simpson’s theory of embodied relational resurgence, and Diana Taylor’s notion of the repertoire as embodied memory beyond the archive, the essay argues that silence, gesture, and affect function as insurgent practices of knowledge transmission that contest colonial modes of erasure. Through an autoethnographic narrative spanning displacement from Villarrica, Tolima, and re-rooting on the territories of the xʷməθkʷəy̓əm, Sḵwx̱wú7mesh, and səlilwətaɬ Nations, the analysis traces how colonial grammars of race, gender, and territory are inscribed in the body. Yet these embodied inscriptions also generate practices of resurgence. By bringing Cabnal, Lugones, Simpson, and Taylor into direct conversation, the essay demonstrates that resurgence must be understood as an embodied, relational, and hemispheric process, one in which the body becomes a generative territory for reimagining belonging and repairing the fractures of colonial modernity. Full article

Background/Objective: To outline strategies for the safe clinical use of orthodontic temporary anchorage devices (TADs) by analyzing papers that examine associated risks, complications, and approaches for their prevention and resolution. Methods: The research protocol used PubMed, Medline, and Scopus up to May 2024, focusing on controlled and randomized clinical trials aligned with the review objective. Fourteen studies were included; bias risk was assessed, key data extracted, and a descriptive analysis performed. Study quality and evidence strength were also evaluated. Results: TADs optimize anchorage control without relying on patient compliance. However, they carry risks and complications. TAD contact with the periodontal ligament or root without pulp involvement requires removal for spontaneous healing. If pulp is involved, the TAD should be removed and endodontic therapy performed. If anatomical structures are violated, TAD should be removed. If transient, spontaneous recovery occurs, but sometimes pharmacological treatment may be needed. A 2 mm gap between the TAD and surrounding structures can prevent damage. In the maxillary sinus, a less than 2 mm perforation of the Schneiderian membrane recovers spontaneously; wider perforations require TAD removal. Good oral hygiene and TAD abutments prevent soft tissue inflammation, which resolves with 0.2% chlorhexidine for 14 days. Unwanted forces can cause TAD fractures, requiring removal. Minor TAD mobility due to loss of primary stability can be maintained; significant instability requires repositioning. Conclusions: The use of TADs requires meticulous planning, radiological guidance, and monitoring to minimize risks and manage complications. With proper care, TADs improve orthodontic outcomes and patient satisfaction. Full article

The Nezamabad Fault System (NFS) in the Fars area of the Zagros Fold–Thrust Belt represents a persistent, basement-rooted transverse shear zone that fundamentally controls the regional hydrocarbon system. This study integrates seismicity distribution, isopach analysis, and tectono-stratigraphic modeling from the Triassic to the Cenozoic to unravel how recurrent basement reactivation governs trap evolution. Isopach maps reveal a pronounced southwest-thickening asymmetry, with Triassic successions exceeding 1400 m, indicating long-term differential subsidence during four key phases: (1) Triassic syn-rift salt accumulation (Dashtak Formation) forming the primary detachment; (2) Jurassic–Early Cretaceous passive subsidence promoting source rock deposition; (3) Mid-Cretaceous transpression enhancing reservoir dolomitization; and (4) Late Cretaceous–Cenozoic inversion generating hybrid traps. Seismicity analysis of over 240 events confirms the 256-km-long NFS is a crustal-scale structure, with most foci at 10–33 km depth and others extending to 150 km, implying lithospheric stress transfer. This deep-crustal activity has periodically reorganized stress, enhanced fracture permeability, and rejuvenated traps through seismic pumping and cross-scale mechanical coupling. The results demonstrate that hydrocarbons in the Fars area are not a passive outcome of folding but a dynamic expression of lithospheric coupling. The findings establish a predictive framework for identifying analogous basement-influenced petroleum systems in other foreland fold–thrust belts worldwide. Full article

Background/Objectives: The clinical outcome of root canal treatments using calcium silicate-based sealer (CSBS) remains unclear. This study aimed to evaluate the 1-year effect of CSBS in combination with a single-cone obturation technique on periapical lesion (PL) healing evaluated on cone beam computed tomography scans (CBCT) after single-visit root canal retreatment. Methods: This randomized clinical study involved 50 patients with chronic apical periodontitis and previous root canal treatment (ClinicalTrials.gov ID: NCT04072926). The inclusion criteria were previous endodontic treatment, asymptomatic inadequate endodontic treatment, PLs measuring > 5 mm, and percussion and palpation sensitivity. The exclusion criteria were immunocompromised status, pregnancy, periodontally compromised teeth, vertical root fracture, and antibiotic usage in the last month. Single-visit root canal retreatment was performed by the same endodontist. The patients were randomly divided into two groups based on the root canal sealer used: CSBS (BioRoot RCS) and epoxy resin-based sealer (ERBS) (AH Plus). Periapical healing, as the primary outcome measure, was determined according to the reduction in PL volume on CBCT from the preoperative period to the 1-year postoperative period. Results: Pre- and postoperative PL volumes (p > 0.05) were not significantly different between the CSBS and ERBS groups. The success rate (loose criteria) was 82.9% in the ERBS group and 94.7% in CSBS group. Conclusions: Root canal retreatment outcomes of CSBS, including periapical healing, are comparable to those of ERBS at 1 year after the retreatment. Full article

Alpacas are frequently affected by dental pathologies, with periapical infection of the cheek teeth being a significant concern. While radiography is commonly used as the primary diagnostic imaging modality, it has known limitations, particularly due to anatomical superimposition. Computed tomography (CT), with its superior spatial resolution, allows for more detailed evaluation and can detect early or subtle changes that may not be visible on radiographs. To date, direct empirical comparisons between radiography and CT in diagnosing apical infections in alpacas have not been documented. In this study, 158 teeth from 19 alpacas were assessed using both radiography and CT, evaluating 16 diagnostic parameters. Inter-modality agreement demonstrated variable consistency across assessed features: No agreement was observed for certain findings such as pulpar changes and the presence of cementomas. Agreement was weak for features including periodontal ligament space widening, periapical halo, lamina dura visibility, root lysis and fragmentation, sequestration, cortical destruction, clinical crown fractures, and the overall impression of periapical infection. Moderate agreement was found for radicular changes, periapical sclerosis, periosteal reaction, mandibular expansion, and alveolar bone alterations. Overall, CT identified more dental abnormalities than radiography, highlighting its value as a complementary diagnostic tool for detecting periapical infections in alpaca cheek teeth. Full article

The seepage characteristics and heat transfer efficiency in rough fractures are indispensable for assessing the lifetime and production performance of geothermal reservoirs. In this study, a two-dimensional rough rock fracture model with different secondary roughness is developed using the wavelet analysis method to simulate the coupled flow and heat transfer process under multiscale roughness based on two theories: local thermal equilibrium (LTE) and local thermal nonequilibrium (LTNE). The simulation results show that the primary roughness controls the flow behavior in the main flow zone in the fracture, which determines the overall temperature distribution and large-scale heat transfer trend. Meanwhile, the nonlinear flow behaviors induced by the secondary roughness significantly influence heat transfer performance: the secondary roughness usually leads to the formation of more small-scale eddies near the fracture walls, increasing flow instability, and these changes profoundly affect the local water temperature distribution and heat transfer coefficient in the fracture–matrix system. The eddy aperture and eddy area fraction are proposed for analyzing the effect of nonlinear flow behavior on heat transfer. The eddy area fraction significantly and positively correlates with the overall heat transfer coefficient. Meanwhile, the overall heat transfer coefficient increases by about 3% to 10% for eddy area fractions of 0.3% to 3%. As the eddy aperture increases, fluid mixing is enhanced, leading to a rise in the magnitude of the local heat transfer coefficient. Finally, the roughness characterization was decomposed into primary roughness root mean square and secondary roughness standard deviation, and for the first time, an empirical correlation was established between multiscale roughness, flow velocity, and the overall heat transfer coefficient. Full article

Background and Objectives: Nickel–titanium (Niti) instruments have enhanced root canal cleaning in primary teeth, but file fractures are still common. Materials and Methods: This study evaluated the cyclic fatigue resistance of 120 Niti files from four different systems, A: Kedo SG (n = 30); B: Neoendo Pedoflex (n = 30); C: Pedoflex Waldent files (n = 30); and D: Vortex Blue files (n = 30). All the files had similar tip diameters (0.25 mm) and tapers (0.4%) and underwent heat treatment during manufacturing. Cyclic fatigue tests showed notable variations in cycles to fracture (NCF) across groups. All fracture surfaces of the files were assessed through scanning electron microscopy. Results: The mean values achieved in the experimental groups (A, B, C) were less than those in the control Group D (976.90 ± 1085.19). Files in Group A demonstrated the highest NCF (697.01 ± 420.09), while Pedoflex files in Group C showed the lowest values (203.88 ± 155.46). Statistical analysis using the Mann–Whitney test revealed significant differences between Group C and Groups A, B, and D and no differences among Groups A, B, and D. Conclusions: These findings suggest that Kedo SG and Neoendo Pedoflex files offer comparable cyclic fatigue resistance to Vortex Blue files. In contrast, Pedoflex Waldent files exhibit lower resistance to fracture. Full article

To investigate the effects of impact and static compaction methods on the mechanical properties and crack evolution of rock-like materials with varying particle sizes. Uniaxial compression tests combined with Digital Image Correlation (DIC) technology were conducted on specimens of two aeolian sand gradations (0.075–0.18 mm and 0.22–0.5 mm) and one quartz sand gradation (0.22–0.5 mm). The study focused on elastic modulus, peak strength, stress-strain behavior, failure modes, surface deformation fields, crack propagation paths, and strain evolution at characteristic points under both compaction methods. Finally, the microstructure of specimens was analyzed and compared with natural rock analogs. Key results include: (1) At an identical density of 1.82 g/cm³, static-compacted specimens of fine-grained aeolian sand (0.075–0.18 mm) exhibited higher elastic modulus and peak strength compared to impact-compacted counterparts, whereas inverse trends were observed for coarse-grained aeolian sand (0.22–0.5 mm) and quartz sand specimens; (2) Under equivalent compaction energy (254.8 J), the hierarchy of mechanical performance was: quartz sand > coarse-grained aeolian sand > fine-grained aeolian sand; (3) Static-compacted specimens predominantly failed through tensile splitting, while impact-compacted specimens exhibited shear-dominated failure modes; (4) DIC full-field strain mapping revealed rapid propagation of primary cracks along pre-existing weak planes in static-compacted specimens, forming through-going tensile fractures. In contrast, impact-compacted specimens developed fractal strain field structures with coordinated evolution of shear bands and secondary tensile cracks; (5) Microstructural comparisons showed that static-compacted fine-grained aeolian sand specimens exhibited root-like structures with high porosity, resembling weakly consolidated sedimentary rocks. Impact-compacted coarse-grained aeolian sand specimens displayed stepped structures with dense packing, analogous to strongly cemented sandstones. Full article

The aim of this study was to compare the efficacy of the guided tissue regeneration (GTR) of periodontal infrabony defects using the frozen radiation-sterilized allogenic bone graft (FRSABG) versus deproteinized bovine bone mineral (DBBM) 5 years after treatment. The association between patients’ compliance and periodontitis recurrence with 5-year outcomes was also evaluated. Thirty infrabony defects in 15 stage III/IV periodontitis patients were randomly allocated to the FRSBAG group (tests) or the DBBM group (controls). Between 1 and 5 years, one patient was lost to follow-up and one tooth was extracted due to root fracture. No tooth was extracted for periodontal reasons. Consequently, 13 teeth in test sites and 14 teeth in control sites were available for the 5-year analysis. The clinical attachment level gain (CAL-G, primary outcome), probing pocket depth (PPD), radiographic defect depth (DD), and linear defect fill (LDF) were examined at baseline and 5 years post-surgically. Both groups showed statistically significant improvements in all evaluated clinical and radiographic parameters at 5 years, with insignificant intergroup differences. CAL-Gs were 4.46 ± 2.07 mm in the FRSBAG group, and 3.86 ± 1.88 mm in the DBBM group (p = 0.5442). In six (43%) patients, we observed periodontitis recurrence, among whom two (33.33%) participated regularly in supportive periodontal care (SPC) and the other four (66.7%) did not take part in SPC. A regression analysis revealed that periodontitis recurrence was a significant predictor of CAL loss and DD increase. FRSBAG and DBBM were both equally effective 5 years after the GTR of infrabony defects. Within the limitations of the present study, its outcomes advocate that both grafts may be considered as a viable option based on patient preferences and clinical considerations. Full article

Background: Hypophosphatasia (HPP) is an inherited disease caused by low activity of tissue-nonspecific alkaline phosphatase. Dental characteristics include premature loss of primary teeth, enlarged pulp chambers, and enamel hypoplasia. Although enzyme replacement therapy with asfotase alfa was approved in 2015, there are few reports about the dental outcomes of this treatment. Case presentation: A 1-year-old girl referred to our hospital had already lost two primary teeth at the time of her initial visit. She started enzyme replacement therapy 6 days after birth, and genetic analysis later confirmed the diagnosis of HPP. At the age of 4 years and 7 months, 11 primary teeth had been lost, and some of the exfoliated teeth showed inflammatory root resorption or root fracture. There was also a history of abscess formation in a non-carious primary molar. Conclusions: This report suggests that early enzyme replacement therapy may prevent traditional tooth loss in patients with HPP. It also highlights the new challenges posed for dental professionals in providing infection control in large pulp cavities and receding periodontal tissue. Full article

This study presents a method to add a crack analysis algorithm to the Acoustic Leak Monitoring System (ALMS) to detect and evaluate the crack growth process in the primary system piping of nuclear power plants. To achieve this, a fracture test was conducted by applying stepwise loading to welded specimens that simulate the cold leg section, and acoustic emission (AE) signals were measured in relation to the increase in strain using an AE testing system. The experimental results indicated that the stability and instability of cracks could be assessed through the Kaiser effect and the Felicity effect when detecting crack growth using AE signals. Additionally, by utilizing both root mean square (RMS) and amplitude parameters simultaneously to calculate the b-value, it was confirmed that the RMS-based b-value minimizes the effects of AE signal attenuation and allows for a more stable assessment of crack progression. This demonstrates that the RMS, which reflects signal energy, is effective for real-time monitoring of the crack growth state. Finally, the results of this study suggest the potential for real-time crack monitoring using AE data in piping systems of critical structures, such as nuclear power plants; by adding a simple AE analysis method to the ALMS system, a practical approach has been derived that enhances the safety of the structure and allows for quantitative assessment of crack progression. Future research is expected to further refine the AE parameters and algorithms, leading to the advancement of safety monitoring systems in various industrial settings. Full article

Background: Root fractures are defined as injuries involving dentine, cementum, and the pulp. They are rare, and they account for 0.5–7% of the dental injuries in the permanent teeth. Root fractures may be the result of direct trauma to the teeth or indirect trauma to the oral cavity. Their incidence is highest in the group of adolescent patients aged 11 to 20 years. The purpose of the paper is to review the literature supported by a case series with three different types of root fractures with various healing patterns, though all with successful long-term treatment outcomes. Case series: All presented patients were boys aged 10 to 11 years. Root fractures occurred as a result of direct impact with the teeth by an object. Only one boy had his root-fractured teeth endodontically treated. However, one of the teeth was misdiagnosed with pulp necrosis, and the other became non-vital after additional trauma. Conclusions: Root fractures in young patients have good healing potential. Appropriate and early diagnostic and therapeutic procedures for treating root-fractured teeth are necessary to achieve favorable healing and a good long-term prognosis. Regardless of the pattern of healing of fractured roots and the treatment provided, patients require long-term follow-up and the need to plan a management strategy in case complications occur. Failure of the healing of fractured root is a worst-case scenario, especially in patients of developmental age. In such cases, the primary goal of treatment is to preserve the alveolar ridge until growth is complete. Full article

Cold acclimation before winter has been shown to enhance the cold tolerance of evergreen conifers, including Pinus massoniana Lamb., a characteristic heteroblastic foliage tree in the conifer. In the initial growing season of P. massoniana, both primary needle seedlings (PNSs) and secondary needle seedlings (SNSs) are generated. While previous research has highlighted differences in the morphological structure and photosynthetic physiological functions of primary and secondary needles, their response to cold acclimation remains poorly understood. This study aimed to investigate the changes in morpho-anatomical structure, starch grain accumulation, and lignin deposition in the roots, stems, and leaves of PNSs and SNSs during cold acclimation using solid potassium iodide and hydrochloric acid phloroglucinol double-staining techniques. The results revealed that, during cold acclimation, the leaves and stems of PNSs exhibited sensitivity to low-temperature stress, resulting in noticeable shrinkage and fracture of mesophyll and cortical parenchyma cells. Furthermore, the early stages of cold acclimation promoted the accumulation of starch grains and lignin in the seedling tissues. In contrast to PNSs, the leaves and stems of SNSs exhibited a shorter cold acclimation period, attributed to the hydrolysis of starch grains in the epidermal cell walls and the transformation of xylem lignin, which supports cell structure stability and enhances cold resistance. In conclusion, these findings suggest that SNSs displayed a superior cold resistance potential compared to PNSs following cold acclimation, providing a significant theoretical basis for the further screening of cold-tolerant germplasm resources of P. massoniana and the analysis of cold resistance traits in heteroblastic foliage. Full article

The introduction of nickel–titanium rotary instruments revolutionized shaping procedures as they were able to produce a well-tapered preparation while reducing operator fatigue. The major drawback of rotary instruments was the high risk of fracture due to bending and torsional stress. Thus, the creation of a glide path has been advocated and recommended by most rotary instrument manufacturers. The aim of the present review is to summarize existing knowledge on glide path preparation and identify areas where further research is needed. The primary goal is to provide a comprehensive overview of the techniques and instruments used in glide path preparation, highlighting their advantages and limitations. The secondary goal is to explore the effect of glide path creation on the overall success of endodontic treatment, particularly in terms of reducing procedural errors and improving treatment outcomes. An online search on PubMed, ScienceDirect, UCLA, and Scopus databases was conducted, and 116 articles were identified. Eligible articles were divided into nine categories based on what they researched and compared. The categories included centering ability and/or root canal transportation, cyclic fatigue resistance, glide path and shaping time, tortional stress resistance, apical extrusion of debris and/or bacteria, defects in dentine walls, file separation, postoperative pain assessment, and scouting ability and performance. Establishing a glide path reduces root canal transportation, especially with rotary methods. Reciprocating and heat-treated files offer higher fatigue resistance and shorter preparation time. Instruments with shorter pitch lengths have greater torsional strength. Preparation and coronal preflaring reduce apical debris and bacteria. Glide paths do not affect dentine microcracks, file separation, or defects but reduce immediate postoperative pain and improve cutting ability. Randomized trials are needed to assess their impact on treatment outcomes. Full article

Orthodontic Mini-Implants have a high success rate, but it is crucial to assess the load that they bear in order to maintain their primary stability. Increasing the diameter can improve this stability, but there are limitations due to the proximity of the tooth roots. To avoid damage, smaller diameters are used, which can decrease resistance and cause permanent deformations. Objective: The objective of this study is to evaluate the influence of the diameter of Mini-Implants through bending force tests, taking into account primary stability after one and two insertions. Methods: Here, 40 Ti6AI4V alloy Mini-Implants of two different brands and diameters were divided into eight groups, half of which received one insertion in the artificial bone, and the rest received two. All were subjected to a constant bending force using an INSTRON-Electropuls E10000LT (Norwood, MA, USA) until fracture. Results: The smaller-diameter Mini-Implants were less resistant to fracture, but both were able to withstand the necessary loads produced by orthodontic movements. As for the inserts, there were no statistically significant differences. Conclusions: There is an advantage to using 1.6 mm Mini-Implants over 2.0 mm ones, as a smaller diameter does not lead to fracture due to the forces used in orthodontic treatment. Having one or two inserts did not have a statistically significant effect. Full article