Comparative Study of the Antioxidant Activity of the Conformers of C-tetra(4-methoxyphenyl)calix[4]resorcinarene.

C-tetra(4-methoxyphenyl)calix[4]resorcinarene was synthesized by hydrochloric acid-catalysed cyclocondensation of resorcinol and 4-methoxybenzaldehyde. Under these conditions, the reaction produces a conformational mixture of crown and chair structural conformers, which were separated and characterized by chromatographic and spectroscopic techniques. The antioxidant activity of both conformers was measured by using the DPPH assay, through which it was observed that the chair conformer showed greater antioxidant activity (IC50 = 47.46 ppm) than the crown conformer (IC50 = 78.46 ppm). Additionally, it was observed that the mixture of both conformers presented lower antioxidant activity than either conformer in isolation. The results found suggest that the chair conformer has efficient antioxidant activity that makes it a potential target for further research.

A Bis(Acridino)-Crown Ether for Recognizing Oligoamines in Spermine Biosynthesis.

Oligoamines in cellular metabolism carry extremely diverse biological functions (i.e., regulating Ca2+-influx, neuronal nitric oxide synthase, membrane potential, Na+, K+-ATPase activity in synaptosomes, etc.). Furthermore, they also act as longevity agents and have a determinative role in autophagy, cell growth, proliferation, and death, while oligoamines dysregulation is a key in a variety of cancers. However, many of their mechanisms of actions have just begun to be understood. In addition to the numerous biosensing methods, only a very few simple small molecule-based tests are available for their selective but reversible tracking or fluorescent labeling. Motivated by this, we present herein a new fluorescent bis(acridino)-crown ether as a sensor molecule for biogenic oligoamines. The sensor molecule can selectively distinguish oligoamines from aliphatic mono- and diamino-analogues, while showing a reversible 1:2 (host:guest) complexation with a stepwise binding process accompanied by a turn-on fluorescence response. Both computational simulations on molecular docking and regression methods on titration experiments were carried out to reveal the oligoamine-recognition properties of the sensor molecule. The new fluorescent chemosensor molecule has a high potential for molecular-level functional studies on the oligoamine systems in cell processes (cellular uptake, transport, progression in cancers, etc.).

Changes in the surface texture of pre-polymerized acrylic resin pediatric crowns following acidulated phosphate fluoride application.

This study aimed to investigate the effect of acidulated phosphate fluoride (APF) application on filler-free polymethyl methacrylate (PMMA)-based resin blocks for computer-aided design/computer-aided manufacturing (CAD-CAM), focusing on their use in pediatric crowns. Three types of PMMA-based blocks for CAD-CAM were evaluated, and a composite resin block for CAD-CAM was used as a control. Statistical analysis (p<0.05) of the data revealed that all PMMA-based blocks showed significantly higher gloss levels than the composite resin blocks. Two PMMA-based blocks also demonstrated significantly lower Ra and Sa values. SEM images showed no irregular changes in the surface properties of the PMMA-based blocks compared to those of the composite resin block. These results are significant in meeting the increasing demand for esthetic restorative treatments in pediatrics, where APF is commonly used for caries prevention. PMMA-based resin blocks for CAD-CAM are an effective alternative to prevent esthetic degradation from gloss reduction and plaque accumulation.

Survival evaluation of surgical extrusion for the management of complicated crown-root fractured maxillary incisors: A clinical study.

This study aimed to clinically evaluate the survivability of surgically extruded teeth, to assess the success rate and predictable factors pertaining to alterations in both hard and soft tissues adjacent to extruded teeth. A total of 46 complicated crown-root fractured maxillary central and lateral incisors with >75% tooth structure loss relatively due to trauma were included. Preoperative clinical and radiographic variables were recorded. Single operator performed endodontic treatment before surgical extrusion. Patients were recalled for review at 6, 12, 18, 24 and 36 months. Survivability was assessed using Kaplan-Meier survival analysis. With a mean follow-up of 2.8 years, survival rate was 95.7%. Mobility observed in only two cases. The crown-root ratio was favourable (1:2) in all the cases except for five teeth. Only two teeth displayed non-progressive root resorption. Survival of surgically extruded teeth relies on significant predictors like favourability of CRR and implementation of atraumatic extrusion.

Uneven changes in air and crown temperatures associated with snowpack changes affect the phenology of overwintering cereals.

Time series analysis of overwintering cereals in snowy areas has revealed several phenological patterns associated with climate changes in winter. Herein, to investigate the recent effect of climatic variations on overwintering cereals, we investigated the phenology over multiple decades at three snowy region sites with an air temperature (Tair) increase trend of 0.48-1.09 °C/decade. Our findings were as follows: heading trends differed within the same cultivar at different sites; phenology was promoted with increasing temperatures in cooler regions and decreasing snow duration in regions with heavy snow; crown temperature (Tcrown) was a more direct determinant than Tair in phenology estimation model in regions with heavy snow. A thermal gap of more than a few degrees Celsius between Tair and Tcrown, owing to the insulation effect of snowpack, affected the phenology of overwintering cereals. A shorter snow cover period promoted phenology in locations with temperatures >0 °C. Subsequently, we found that when the thermal gap was >0 °C of the growing temperature range, Tcrown directly helped determine the phenology of overwintering cereals, and irrespective of the warming trend, the periodic inflow of cold air into the northern mid-latitudes of the Northern Hemisphere and associated snow cover changes dominated Tcrown, resulting in annual phenological anomalies with a range of fluctuations of approximately 1 month. The trend of increasing Tair during spring in northern Japan is consistent with the global trend, with a pronounced trend of advancing phenology reaching >4 days/decade in a typical cooler location experiencing snowmelt in March.

Automated Crack Detection in Monolithic Zirconia Crowns Using Acoustic Emission and Deep Learning Techniques.

Monolithic zirconia (MZ) crowns are widely utilized in dental restorations, particularly for substantial tooth structure loss. Inspection, tactile, and radiographic examinations can be time-consuming and error-prone, which may delay diagnosis. Consequently, an objective, automatic, and reliable process is required for identifying dental crown defects. This study aimed to explore the potential of transforming acoustic emission (AE) signals to continuous wavelet transform (CWT), combined with Conventional Neural Network (CNN) to assist in crack detection. A new CNN image segmentation model, based on multi-class semantic segmentation using Inception-ResNet-v2, was developed. Real-time detection of AE signals under loads, which induce cracking, provided significant insights into crack formation in MZ crowns. Pencil lead breaking (PLB) was used to simulate crack propagation. The CWT and CNN models were used to automate the crack classification process. The Inception-ResNet-v2 architecture with transfer learning categorized the cracks in MZ crowns into five groups: labial, palatal, incisal, left, and right. After 2000 epochs, with a learning rate of 0.0001, the model achieved an accuracy of 99.4667%, demonstrating that deep learning significantly improved the localization of cracks in MZ crowns. This development can potentially aid dentists in clinical decision-making by facilitating the early detection and prevention of crack failures.

Comparison of Various Surface Treatment Procedures on the Roughness and Susceptibility to Staining of Provisional Prosthodontic Materials.

Esthetically pleasing temporary prostheses are often necessary for extended periods in a variety of clinical scenarios. Adjustments to the occlusion or margins are commonly needed before cementing the temporary prosthesis. Therefore, it is clinically necessary to repolish the rough surface to avoid biological and esthetic issues associated with rough surfaces. The purpose of this in vitro study was to assess and compare the impact of various polishing protocols on the surface roughness and color stability of three resin materials used for provisional crowns. A total of 150 specimens were fabricated from auto-polymerizing polymethyl methacrylate, bis-acryl composite, and Methyl methacrylate-LC resin using a stainless steel mold. Each material group was divided into five groups (n = 10) based on the applied surface treatment: positive control group (G1): no roughening or surface treatment, Negative control group (G2): acrylic bur-roughened surface without any polishing, the different surface treatment groups of silicon carbide and aluminum oxide stone polishing (G3), diamond-coated rubber twist (G4), and Surface Glaze (G5). An optical profilometer was used to assess the surface roughness of all samples. After undergoing 6000 cycles of thermocycling followed by immersion in a coffee solution for 15 days at 37 °C, color parameters were measured using a spectrophotometer both before and after a storage period to evaluate color differences. A two-way ANOVA test with α = 0.05 significance level was carried out to determine the impacts of both the materials utilized and the polishing protocol. Among the three types of resin examined, the bisacryl group exhibited superior surface quality in positive control groups, while PMMA resin demonstrated higher polishability. The diamond-coated rubber twits resulted in lower Ra values of 0.36 (0.01) µm, 0.52 (0.11) µm, and 0.28 (0.05) µm for PMMA, BAMA, and MMLC resins, respectively. The application of photo-polymerized surface glaze led to a plaque accumulation threshold of 0.2 µm across all resin groups. The greatest mean color change occurred in the negative control group, indicating a propensity for more staining on rougher surfaces. The Bisacryl resin exhibited higher ΔE values, whereas PMMA showed better color stability. The lowest ΔE values were found when the surface glaze was applied to all of the provisional crown resins. Untreated Bisacryl resin exhibited the lowest Ra values, while PMMA resins demonstrated superior surface morphology after polishing. PMMA provisional crown resins showed increased resistance to staining. The use of surface glaze enhanced both smoothness and color stability on the surfaces.

Stress Distribution of Pediatric Zirconia and Stainless Steel Crowns after Pulpotomy Procedure under Vertical Loading: A Patient-Specific Finite Element Analysis.

Aim: With modern dentistry advancements, children and parents have significantly raised aesthetic expectations in pediatric dentistry. Pediatric zirconia crowns (PZCs) provide a superior aesthetic appearance compared with stainless steel crowns (SSCs), making them a popular treatment option. However, a comparison of the compressive stresses caused by these crowns on the roots of primary teeth and alveolar bones has not been conducted. Materials and Methods: Cone beam computed tomography (CBCT) images of an eight-year-old female patient who experienced premature loss of a primary mandibular left second molar were obtained from a dental hospital database. Rhinoceros 4.0 software was used to process and simulate images. Under simulated chewing forces, stress on the PZC, SSC, and intact primary first molars as control groups, as well as their roots and alveolar bone structures, was assessed with finite element analysis. Statistical Analyses: Depending on whether the descriptive data were normally distributed, the Student t-test and Mann-Whitney U test were used. Quantitative variables differ between the two categories of qualitative variables. One-way ANOVA and Kruskal-Wallis H tests were used depending on standard distribution assumptions. p < 0.05 indicates statistical significance differences. Results: PZCs, SSCs, and cement layers were stressed according to von Mises values, while roots and alveolar bones were stressed according to maximum and minimum stress values. When assessing crowns, SSCs exhibited the highest von Mises stress values, followed by PZCs and control groups (p < 0.001). In the cement layer, SSCs obtained significantly higher values (p = 0.003). In the root area, minimum principal stress values are more critical. The highest values were obtained from the intact tooth, PZC, and SSC, respectively (p < 0.001). Alveolar bones did not differ significantly in minimum principal stress (p = 0.950). Conclusions: Restorative full-coverage crowns exhibited higher von Mises values than intact teeth, as per current research findings. The von Mises values were highest in SSC, while lowest in PZC. As a result of this condition, the cement layer and root areas had higher von Mises stress and compressive stress. Alveolar bones were not affected regardless of restoration type. PZC transmits higher stress due to its properties.

Characterisation of Fusarium oxysporum f. sp. radicis-lycopersici in Infected Tomatoes in Inner Mongolia, China.

Fusarium crown and root rot (FCRR), caused by Fusarium oxysporum f. sp. radicis-lycopersici (FORL), is an economically important disease that affects tomatoes worldwide and has become more prevalent in China in recent years. In 2021 and 2022, tomato plants in greenhouses in Hohhot, Inner Mongolia, were observed showing symptoms of stunting, premature loss of lower leaves, and root rot. Fungal pathogens were isolated from 20 infected tomato plants and identified based on morphological observation and DNA sequencing. Twelve isolates were consistently identified as Fusarium oxysporum f. sp. radicis-lycopersici (FORL) via an analysis of the ITS, TEF-1α, and pgx4 genes. This is the first report of FORL in Inner Mongolia, China. The isolates were examined for their pathogenicity by inoculating them on tomatoes, eggplants, peppers, and chickpeas. The fungicide sensitivity of the isolates was determined. Effective concentrations for 50% growth inhibition (EC50) were measured using seven fungicides. The EC50 values of tebuconazole and prochloraz were <1.0 µg·mL-1, exhibiting the most effective inhibition among the fungicides tested. Additionally, FORL resistance screening of tomato germplasms was performed. One tomato variety was resistant to FORL, and the remaining 43 germplasm lines showed various levels of resistance. The rates of highly susceptible, moderately susceptible, susceptible, and moderately resistant germplasms accounted for 29.55%, 22.73%, 40.91%, and 4.55% of the 44 germplasms tested, respectively.

Exploring the Biocontrol Potential of Phanerochaete chrysosporium against Wheat Crown Rot.

The worldwide occurrence of wheat crown rot, predominantly caused by the pathogen Fusarium pseudograminearum, has a serious impact on wheat production. Numerous microorganisms have been employed as biocontrol agents, exhibiting effectiveness in addressing a wide array of plant pathogens through various pathways. The mycelium of the white-rot fungus Phanerochaete chrysosporium effectively inhibits the growth of F. pseudograminearum by tightly attaching to it and forming specialized penetrating structures. This process leads to the release of intracellular inclusions and the eventual disintegration of pathogen cells. Furthermore, volatile organic compounds and fermentation products produced by P. chrysosporium exhibit antifungal properties. A comprehensive understanding of the mechanisms and modalities of action will facilitate the advancement and implementation of this biocontrol fungus. In order to gain a deeper understanding of the mycoparasitic behavior of P. chrysosporium, transcriptome analyses were conducted to examine the interactions between P. chrysosporium and F. pseudograminearum at 36, 48, and 84 h. During mycoparasitism, the up-regulation of differentially expressed genes (DEGs) encoding fungal cell-wall-degrading enzymes (CWDEs), iron ion binding, and mycotoxins were mainly observed. Moreover, pot experiments revealed that P. chrysosporium not only promoted the growth and quality of wheat but also hindered the colonization of F. pseudograminearum in wheat seedlings. This led to a delay in the development of stem base rot, a reduction in disease severity and incidence, and the activation of the plant's self-defense mechanisms. Our study provides important insights into the biocontrol mechanisms employed by P. chrysosporium against wheat crown rot caused by F. pseudograminearum.

Direct Versus Indirect Treatment Options of Endodontically Treated Posterior Teeth: A Narrative Review.

One of the controversial topics in dentistry is restoring endodontically treated posterior teeth. Most posterior teeth that undergo endodontic treatment are subjected to a high rate of fracture due to excessive amount of loss of tooth structure. The aim of this review is to evaluate and compare the restorative and prosthetic treatment options to provide clinical recommendations for restoring endodontically treated posterior teeth. Both Medline on PubMed and Google Scholar were utilized for the search. The terms on our keyword list were "crown," "onlay," "endo-crown," "amalgam," and "composite," with the time frame from 1977 to 2024. We also examined the reference lists of potentially relevant papers for any recent review articles. Our analysis examined review articles found through computerized searches, along with relevant citations from the bibliographies of those studies. This review will focus on the dental restorative options and the amount of remaining tooth structure in determining the final restoration of an endodontically treated posterior tooth. This narrative review addresses different treatment options for endodontically treated posterior teeth based on the amount of remaining tooth structure. In addition, it compares the survival rate and the limitations among direct and indirect restorations.

Can deep learning-designed anterior tooth-borne crown fulfill morphologic, aesthetic, and functional criteria in clinical practice?

OBJECTIVES: This study aimed to compare the design outcomes of anterior crowns generated using deep learning (DL)-based software with those fabricated by a technician using conventional dental computer-assisted design (CAD) software without DL support, with a focus on the evaluation of crown morphology, function, and aesthetics. METHODS: Twenty-five in vivo datasets comprising maxillary and mandibular arch scans of prepared maxillary central incisors were utilized to design anterior crowns by using three methods: 1) a DL-based method resulting in as-generated outcome (DB), 2) a DL-based method further optimized by a technician (DM), and 3) a conventional CAD-based method (NC, control). Evaluations were conducted for crown morphology (total discrepancy volume (TDV), root mean square (RMS), positive average (PA) and negative average (NA) deviations), functional aspects (incisal path: deviations, length, and mean inclination), and aesthetics (crown width, height, width-to-height ratio, angular radius of mesioincisal line angle, proximal contact length, and tooth axis angle). RESULTS: Significant differences in TDV ratio were noted between the DB-NC (32.3 ±8.5%) and DM-NC (26.5 ±5.4%) pairs (P = 0.006). No significant differences were observed in TDV between the DB-NC (65.3 ±24.4 mm3) and DM-NC (54.3 ±21.0 mm3) pairs (P = 0.095). For the entire palatal surface, significant differences in RMS and PA values were observed between the DB-NC and DM-NC pairs (P < 0.037). Significant differences in RMS values for the incisal half (P = 0.021) and in PA values for the cervical half (P = 0.047) of the palatal surface were also noted between these pairs. Significant differences in the deviation of the incisal path were observed between the DB-NC (290.4 ±212.4 µm) and DM-NC (132.0 ±122.3 µm) pairs (P<0.001). However, no significant differences were found among the groups (DB, DM, and NC) in terms of the length and mean inclination of incisal paths or in aesthetic outcomes. CONCLUSIONS: A DL-based method can result in promising outcomes with clinically acceptable morphology and aesthetics for anterior crowns. Minor deviations in incisal path of the crowns may lead to anterior guidance discrepancies, which can be corrected by the dental technician at the design stage. CLINICAL SIGNIFICANCE: With the potential of DL-based design methods in dental applications, integrating AI technology into dental CAD workflow can enhance the clinical efficiency and consistency of anterior crown design, although human intervention may be required to refine functional aspect.

Survival, technical and biological outcome of fixed tooth- and implant-supported restorations: a retrospective analysis of a patient cohort treated in an undergraduate dental education program.

OBJECTIVES: There is a paucity of data on the outcome of fixed tooth- and implant-supported porcelain-fused-to-metal (PFM) and ceramic-based (CB) restorations fabricated during undergraduate dental education. Therefore, this retrospective study examined the outcome of fixed restorations placed in patients participating in an undergraduate program. METHODS: Patient records were searched for data on fixed PFM and CB restorations. For these restorations, the functional period in situ and technical and biological complications, namely restoration fracture, decementation, screw loosening, secondary caries, and loss of vitality, were recorded. Periodontal parameters were also documented. Kaplan-Meier survival and complication estimates after 1 and 5 years were calculated for restoration types, materials, designs (veneered/non-veneered), cementation/retention modes and localizations with group sizes ≥ 15. Regression models were used to analyze the influence of demographic data and abovementioned restoration characteristics on restoration survival, technical and biological outcome. RESULTS: 1196 restorations with a mean observation time of 5 years were included in the analysis. The different restoration types exhibited survival rates of more than 90.8 % after 5 years, accompanied by a favorable biological outcome. However, monolithic resin-matrix or feldspathic ceramic restorations were found to have a higher fracture rate than lithium disilicate or zirconium dioxide ceramic restorations resulting in lower survival rates for these restorations. Additionally, resin-matrix ceramic restorations showed a higher decementation rate than lithium disilicate restorations. CONCLUSIONS: Fixed tooth- and implant-supported CB restorations fabricated from lithium disilicate and zirconium dioxide ceramics demonstrated better survival and lower complication rates than restorations fabricated from resin-matrix or feldspathic ceramics in an undergraduate dental education program. CLINICAL SIGNIFICANCE: Due to the more favorable outcome of CB restorations fabricated from lithium disilicate or zirconium dioxide ceramics, undergraduate dental education should focus on the application of these ceramics to increase restoration survival by reducing technical complications.

Restricting Linker Rotation in Nanocages of ZIF-8 Membranes using Crown Ether "Molecular Locks" for Enhanced Propylene/Propane Separation.

ZIF-8 membranes have long been prized for their exceptional C3H6/C3H8 separation performance. On the other hand, ZIF-8 has structural flexibility, where the external pressure triggers channel expansion, potentially deteriorating the molecular sieving ability. Here, we demonstrate a reliable strategy to fine-tune the flexible pore structure of ZIF-8 by embedding crown ether within a ZIF-8 membrane. Benzo-15-crown-5 (15C5) was selected as the cavity occupant and perfectly confined in the sodalite (SOD) cage of ZIF-8. The 15C5 molecules, which have a size comparable to the nanocage, impose a spatial constraint on linker rotation, enabling the phase transition to a rigid structure in the flexible ZIF-8. The corresponding 15C5@ZIF-8 membranes achieve an ultrahigh C3H6/C3H8 selectivity of 220, outperforming that of most membranes. Unlike their flexible counterparts, the resulting membranes manifest a positive increase in the C3H6/C3H8 separation factor with elevated pressure, securing a record-high C3H6/C3H8 separation factor of 331 under 7 bar. More importantly, extraordinary separation stability was demonstrated with continuous measurement, which is highly desirable for practical applications.

Association of crown-root ratio and tooth survival in Chinese patients with advanced periodontitis: An 11-year retrospective cohort study.

INTRODUCTION: Periodontitis is a chronic multifactorial inflammatory disease which eventually lead to tooth loss (TL). Therefore, a retrospective study was conducted to evaluate the status of tooth survival within 11 years after non-surgical periodontal treatment (NSPT) and to analyze the risk factors especially crown-root ratio (CRR) that affected TL in Chinese with advanced periodontitis. METHODS: 3481 teeth of 131 subjects who underwent NSPT were examined retrospectively within a mean follow-up period of 11.6 years. The association of risk factors including clinical and radiographic parameters with TL was assessed using univariate and multivariate Cox regression analyses. Smooth curve fitting and segmented regression model were conducted to show the nonlinear relationship and the threshold effect between CRR and the risk of TL. RESULTS: 347 teeth were lost in 97 patients in this study. Male, diabetes mellitus, heavy-smoker, molar, probing depth (PD), attachment loss (AL), bleeding on probing (BOP), tooth mobility, and radiographic bone loss were significantly associated with tooth loss (P < 0.05). A nonlinear relationship between CRR and the risk of TL was found, with different turning point values between molars and non-molars (1.9 vs. 2.76). CONCLUSIONS: The findings based on practice-based clinical and radiographic data do suggest a nonlinear relationship between CRR and the survival of teeth, and provide evidence to help clinicians to determine the prognosis of teeth for patients with advanced periodontitis. CLINICAL SIGNIFICANCE: Based on clinical and radiographic data, this study provides an individualized basis for clinicians to judge the dental prognosis of patients with advanced periodontitis according to the different tooth sites.

Efficacy evaluation of zirconia crown on primary molars with caries defects.

OBJECTIVES: This study aimed to estimate the therapeutic effects of preformed metal crown (PMC) and prefabricated zirconia crowns (ZC) on decayed primary morals in children, as well as to analyze the possible influencing factors. METHODS: A retrospective cohort study was performed on the data of 192 patients (aged 3 to 8) in the Stomatological Department of Shenzhen Children's Hospital from October 2021 to December 2021. The decayed mandibular first molars were selected and restored by vital-pulp therapy followed by PMC and ZC, including 96 cases (96 caries) in the PMC group and 96 cases (96 caries) in the ZC group. Oral clinical examination was performed at 3 months, 1 year, and 2 years after treatment, overwiewing the clinical therapeutic effects and periodontal status of PMC and ZC groups, as well as recording the crown integrity, gingival index (GI), probing bleeding index (BI), plaque index (PLI) and various prosthetic indices. RESULTS: No significance differences existed in the periodontal status of PMC and ZC groups at 3 months, 1 year, and 2 years after treatment (P>0.05). However, the GI, BI, and PLI in the PMC group were higher than those in the ZC group at 3 months, 1 year, and 2 years after treatment, and the difference was dramatically significant (P<0.05). No significances difference existed in various prosthetic indices (P>0.05), as well as in the GI, BI, and PLI, between the two groups (P>0.05). No significant differences existed in various prosthetic indices between genders after PMC restoration (P>0.05). The scores of girls in various prosthetic indices after ZC restoration were higher than those of boys (P<0.05). Pearson correlation analysis indicated an inverse correlation between age in the PMC group and the GI, BI, PLI, and FDI indices (P<0.01), rather than in the ZC group (P>0.05). CONCLUSIONS: PMC and ZC can be applied to restore deciduous molar caries. The periodontal status of deciduous teeth in ZC group was superior to that in the PMC group. The periodontal status of deciduous teeth in PMC group may be stable with increased age.

Anterior Endocrowns as An Alternative to Core Crown restorations: A Systematic Review.

Restoring extensively damaged endodontically treated teeth presents a challenging task due to the state of biomechanical deterioration affecting long-term prognosis. Therefore, the study aims to assess and compare the biomechanical performance of endocrowns and post core-crown restorations in anterior endodontically treated teeth with severe coronal structure loss. Following PRISMA guidelines, a systematic search was conducted using PubMed, Scopus, Web of Science, and Google Scholar for articles published from January 2014 to March 2024. Two independent reviewers screened and selected studies based on the predefined inclusion and exclusion criteria. The included studies were analyzed using the QUIN tool for risk of bias assessment in in-vitro studies. Additionally, the biomechanical outcomes were collected for qualitative comparative analysis. Twelve studies were included in this systematic review. In most studies, Endocrowns demonstrated comparable fatigue resistance under load to failure to post core-crown restorations. Endocrowns without ferrule exhibited a higher rate of debonding but had significantly more repairable failures. Conversely, post core-crown restorations demonstrated higher fracture resistance with the presence of ferrule, but were associated with more catastrophic failure patterns. Additionally, endocrowns generated lower stress levels in both the restorative material and the luting material compared to post core-crown restorations. Among the tested materials, lithium disilicate ceramics provided the best biomechanical properties. Overall, the studies included provided sufficient information for most evaluation criteria of the QUIN risk of bias assessment tool. Endocrowns are a viable and conservative approach for restoring endodontically treated anterior teeth, offering comparable biomechanical performance to traditional post core-crown restorations and less catastrophic failures. The findings of this systematic review suggest that endocrown restorations, especially with lithium disilicate ceramics and proper ferrule design, can improve fracture resistance and longevity of rehabilitated teeth, enhancing patient outcomes for severely damaged anterior endodontically treated teeth.

Directional Ring Translocation in a pH- and Redox-Driven Tristable [2]Rotaxane.

We describe the synthesis and characterization of a [2]rotaxane comprising a dibenzo-24-crown-8 (DB24C8) macrocyclic component and a thread containing three recognition sites: ammonium (AmH+), bipyridinium (Bpy2+) and triazolium (Trz+). AmH+ and Bpy2+ are responsive to fully orthogonal stimuli, pH and electrochemical, which allows to precisely control the directional translation of the macrocycle along the axle. A better understanding of the processes driving the operation of the system was obtained thanks to an in-depth thermodynamic characterization. Orthogonal stimuli responsive tristable rotaxanes represent the starting point for the creation of linear motors and the development of molecular logic gates.

From Decay to Delight: A Case Report on Esthetic Rehabilitation in Early Childhood Caries.

Early childhood caries (ECC) continues to be a major global dental health concern for young children. This case report examines a young patient's transformation from decay to delight via comprehensive esthetic treatment. ECC in a four-year-old child resulted in significant dental caries and poor esthetics. In addition to space maintenance and orthodontic examination, essential treatments included dental extractions, stainless steel crowns, and composite restorations. The result showed that the child's smile and self-esteem had been successfully restored, as well as their oral health and function. This case emphasizes the value of early intervention, multidisciplinary teamwork, and individualized treatment plans in the management of early childhood caries and the restoration of pediatric patients' oral health.