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关键词： Imaging   Precision   Indirect bonding   Three-dimensional image   Computer-aided design  

摘要： Introduction/Objectives The adoption of indirect bonding in orthodontics has grown substantially in recent years. The incorporation of a computer-aided design/computer-aided manufacturing (CAD/CAM) approach can improve bracket positioning precision and potentially reduce treatment time. Additionally, cone-beam computed tomography (CBCT) enables three-dimensional evaluation of both crowns and roots, and the integration of digital models with CBCT data may enhance the precision of the indirect bonding process. This study aims to evaluate the precision of bracket placement in indirect bonding, with and without the superimposition of CBCT images onto digital models, as performed by orthodontists. Methods A total of 22 orthodontists participated in this study. Each orthodontist performed virtual bonding on digital models using OrthoAnalyzer (TM) software (3Shape A/S, Copenhagen, Denmark) in two stages: first, visualizing only the clinical crowns, and after a minimum interval of 15 days, visualizing both the crowns and roots with the aid of CBCT images. Bracket positioning discrepancies between the two bonding sessions were measured to assess intra-operator consistency. Positional deviations were analyzed in three dimensions: vertical, horizontal, and angular. Statistical analysis was conducted at a significance level of 5%. Results Positional deviations were within clinically acceptable limits for both horizontal and vertical dimensions, with deviations measuring less than 0.5 mm. However, angular deviations exceeded the clinically acceptable threshold of 2 degrees for certain dental elements. Conclusion The results indicate that orthodontists maintained consistent precision in the vertical and horizontal dimensions. However, the integration of CBCT data affected the precision of angular measurements. Clinical significance These findings suggest that incorporating CBCT into the indirect bonding workflow alters bracket placement in certain angular dimensions for specific

关键词： 3D-printed composite   bilayered restorations   CAD/CAM   fracture resistance   inlays   short fiber-reinforced composite  

摘要： Objectives: This study aimed to evaluate the effect of different bulk-fill base materials and inlay fabrication techniques on the fracture resistance of structurally compromised premolars. Material and Methods: Sixty intact premolars were randomly allocated to five groups (n = 12). Standardized slot-type mesio-occluso-distal cavities with undermined cusps were prepared in all groups except the intact control group. Teeth were restored with different base materials: flowable bulk-fill composite resin (BF-RBC) or short fiber-reinforced composite (SFRC) resin. Each group was further subdivided according to the fabrication technique of the CAD/CAM inlays (milled hybrid nano-ceramic composite or 3D-printed ceramic-filled hybrid composite resin). Fracture resistance was evaluated after thermocycling aging for 10,000 cycles, and the failure mode was inspected. Data were analyzed using heteroscedasticity-corrected two-way ANOVA with post hoc pairwise comparisons of the significant main effect (alpha = 0.05). Results: Fracture resistance was significantly influenced by inlay fabrication technique (p < 0.001) but not by base material or their interaction. In milled groups, SFRC exhibited a statistically more favorable failure mode than BF-RBC, whereas no significant differences were observed in 3D-printed groups. Conclusions: CAD/CAM-milled restorations demonstrated superior fracture resistance compared with 3D-printed restorations in structurally compromised premolars. Clinical Significance: Selecting restorative materials with appropriate compliance is essential to accommodate tooth flexure and minimize fracture risk. CAD/CAM composite restorations provide a conservative approach for restoring structurally compromised premolars, and base material selection should be considered to enhance the stress distribution of the overlying inlay and support overall restoration longevity.

关键词： atherosclerosis   CTRP4   RAGE   TLR4  

摘要： Background C1q/TNF-related proteins (CTRPs) belong to the adipokine family. Here, we aimed to assess the relation of CTRP4 levels in serum and perivascular adipose tissue (PVAT) with coronary artery disease (CAD), and investigate the effect of CTRP4 on atherosclerosis and the underlying *** CTRP4 levels were examined in serum and epicardial adipose tissue (a major PVAT) from patients with CAD. Atherosclerotic lesions were analysed in CTRP4-/-/ApoE-/- and ApoE-/- mice. The paracrine effects of CTRP4 on atherosclerosis were tested by supplementation with CTRP4, either via PVAT transplantation or tail vein injection in CTRP4-/-/ApoE-/- mice. CTRP4-interacting proteins were identified using immunoprecipitation and mass *** CTRP4 levels were lower in serum and epicardial adipose tissue of patients with CAD compared to non-CAD controls. CTRP4 knockout promoted atherosclerosis in ApoE-/- mice. Supplementation of CTRP4, but not receptor for advanced glycation end-products (RAGE)- and toll-like receptor 4 (TLR4)-binding incompetent CTRP4 mutant, either through adipose tissue transplantation from wild-type mice or intravenous injection of recombinant protein, attenuated atherosclerosis in CTRP4-/-/ApoE-/- mice. In macrophages, CTRP4 protein, but not the mutant, suppressed the expression of lipopolysaccharide-induced inflammatory cytokines. Mechanistically, the anti-atherogenic effects of CTRP4 were mediated by the engagement and inhibition of RAGE and *** Decreased CTRP4 levels in serum and epicardial adipose tissue are associated with CAD in patients. CTRP4 deficiency promotes the development of atherosclerosis in ApoE-/- mice, whereas CTRP4 supplementation attenuates atherosclerosis via binding and inhibition of RAGE and TLR4. These results suggest that CTRP4 is a novel anti-inflammatory and anti-atherogenic adipokine inversely associated with CAD and a potential therapeutic target.

关键词： dimension   quantity takeoff   2D CAD   3D BIM   semantic vertex  

摘要： Featured Application Automating the transfer of user-defined dimensions across geometrically identical *** In construction projects, dimensioning automation is now implemented with relatively high precision in both 2D CAD and 3D BIM environments when conditions are clearly defined. For identical or similar objects with the same attributes, dimension-based quantity takeoff formulas can be automated, and such automated formulas can be repeatedly applied as long as the geometric form and attributes remain unchanged. However, this automation is feasible only within limited environments and under pre-defined rules. Once the geometry is slightly altered or geometric identity is disrupted, directly applying the existing automated mechanism becomes structurally constrained. This is because (1) quantity takeoff formulas are difficult to standardize universally, (2) object orientation is often difficult to determine consistently, and (3) even minor geometric changes can alter the meaning of dimensions, making automatic interpretation problematic. Accordingly, this study aims to systematically and experimentally analyze the practical limits of transferring semantic-vertex-based quantity takeoff formulas. To this end, a single isolated footing is adopted as a common reference object, and the limits of user-defined dimension-based automation in 2D CAD and 3D BIM environments are evaluated through three core comparisons: 1. 2D-3D reliability comparison: consistency of final quantity results within an acceptable tolerance range for the isolated footing;2. User dependency assessment (3D-focused): the extent to which quantity takeoff formulas in 3D BIM depend on user judgment;3. User-defined dimension transfer limits: the practical limits of transferring user-defined dimensions between geometrically identical isolated footings in both 2D and 3D environments. Through this analysis, this study empirically confirms that geometric variation is a key factor structurally cons