A nomogram-based predictive model for tooth survival in Chinese patients with periodontitis: An 11-year retrospective cohort study.

AIM: To develop a nomogram-based predictive model of tooth survival by comprehensively analysing clinical and radiographic risk factors of tooth loss (TL). MATERIALS AND METHODS: In this study, 3447 teeth of 131 subjects who underwent non-surgical periodontal treatment 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. A nomogram-based predictive model was developed, and its validation and discriminatory ability were analysed. RESULTS: In all, 313 teeth were lost in 94 patients in this study (overall tooth loss [OTL] 9.08%; 0.21 teeth/patient/year). Male, heavy smoking, molar teeth, probing depth (PD), attachment loss (AL), tooth mobility and radiographic bone loss were significantly associated with TL (p < .05). A gradient effect of tooth mobility on TL increased from degree I to III versus none (p < .0001). The area under the curve (AUC) of the model was 0.865. Calibration curve and decision curve analysis demonstrated good performance and high net benefit, respectively. CONCLUSIONS: Adopting a specific nomogram could facilitate the prediction of tooth survival and the development of tailored treatment plans in Chinese patients with advanced periodontitis.

A nomogram prediction for mandibular molar survival in Chinese patients with periodontitis: A 10-year retrospective cohort study.

AIMS: To develop a nomogram prediction model of mandibular molar survival by comprehensively analysing clinical and radiographic risk factors of mandibular molar loss. MATERIALS AND METHODS: Four hundred and seventy-eight mandibular molars of 139 subjects who underwent non-surgical periodontal treatment were examined retrospectively within a mean follow-up period of 11.1 years. The association of risk factors including clinical and radiographic parameters with mandibular molar loss was assessed using univariate and multivariate Cox regression analyses. A nomogram prediction model was developed, and the validation and discriminatory ability of it were analysed. RESULTS: Hundred and four molars were lost in this study. Probing depth (PD), attachment loss (AL), furcation involvement (FI), bleeding on probing (BOP), tooth mobility and radiographic bone loss were significantly associated with tooth loss (p < .01). A gradient effect of degree of FI on mandibular molar loss existed increasing from degree Ⅱ (HR = 2.37, 95% CI: 1.48, 3.79) to Ⅲ (HR = 5.61, 95% CI: 3.01, 10.45) versus none & degree Ⅰ. The area under the curve (AUC) of the model was 0.891. The calibration curve and decision curve analysis demonstrated good performance and high net benefit of nomogram, respectively. CONCLUSIONS: A specific nomogram could be adopted to predict the mandibular molar survival and formulate tailored treatment plans in Chinese.

Correlation between clinical parameters of crown and gingival morphology of anterior teeth and periodontal biotypes.

BACKGROUND: In this study, we conducted a quantitative analysis of the clinical parameters of crown and gingival morphology (CGM) of the maxillary anterior teeth (MAT). We also analyzed the correlation of these parameters with periodontal biotype (PB), with a view to providing objective standards for PB diagnosis. METHODS: The three-dimensional (3D) maxillary digital models of 56 individuals were obtained using an intra-oral scanner. The following parameters were measured with the SpaceClaim software: gingival angle (GA), papilla width (PW), papilla height (PH), crown length (CL), crown width (CW), crown width/crown length ratio (CW/CL), bucco-lingual width of the crown (BLW), contact surface width (CSW), and contact surface height/crown length ratio (CS/CL). The PB were determined based on the transparency of the periodontal probe through the gingival sulcus. Independent factors influencing PB were analyzed by logistic regression, and the optimal cutoff values for the independent influencing factors were analyzed using receiver operating characteristic curves (ROC curves). RESULTS: There was no significant difference in the parameters of CGM of the MAT at the left and right sides. The thick biotype accounted for 69.6%, and the parameters of GA, PW, PH, CW, CW/CL and CS/CL were significantly correlated with PB (P ≤ 0.2). GA (odds ratio (OR) = 1.206) and PW (OR = 5.048) were identified as independent predictive factors of PB, with areas under the ROC curve (AUC) of 0.807 and 0.881, respectively, and optimal cutoff values of 95.95° and 10.01 mm, respectively. CONCLUSION: The CGMs of the MAT at the left and right side are symmetrical. The thin biotype accounts for a small proportion, and GA and PW are independent influencing factors of PB. GA of 95.95° and PW of 10.01 mm are the optimal cutoff values for categorization of individuals as thick biotype. This indicates that when the GA and PW of the right maxillary central incisor are G ≥ 95.95° and ≥ 10.01 mm, respectively, there is a higher probability that these individuals will be categorized as thick biotype.

NMR method for accurate quantification of polysorbate 80 copolymer composition.

(13)C NMR spectroscopic integration employing short relaxation delays and a 30° pulse width was evaluated as a quantitative tool for analyzing the components of polysorbate 80. (13)C NMR analysis revealed that commercial polysorbate 80 formulations are a complex oligomeric mixture of sorbitan polyethoxylate esters and other intermediates, such as isosorbide polyethoxylate esters and poly(ethylene glycol) (PEG) esters. This novel approach facilitates the quantification of the component ratios. In this study, the ratios of the three major oligomers in polysorbate 80 were measured and the PEG series was found to be the major component of commercial polysorbate 80. The degree of polymerization of -CH2CH2O- groups and the ratio of free to bonded -CH2CH2O- end groups, which correlate with the hydrophilic/hydrophobic nature of the polymer, were analyzed, and were suggested to be key factors for assessing the likelihood of adverse biological reactions to polysorbate 80. The (13)C NMR data suggest that the feed ratio of raw materials and reaction conditions in the production of polysorbate 80 are not well controlled. Our results demonstrate that (13)C NMR is a universal, powerful tool for polysorbate analysis. Such analysis is crucial for the synthesis of a high-quality product, and is difficult to obtain by other methods.

Unraveling fluorescent mechanism of biomass-sourced carbon dots based on three major components: Cellulose, lignin, and protein.

The complexity of biomass components leads to significant variations in the performance of biomass-based carbon dots (CDs). To shed light on this matter, this study presents a comparative analysis of the fluorescence properties of CDs using pure cellulose, lignin, and protein as models. Three CDs showed different fluorescent properties, resulting from the structure difference and carbonization behavior in the hydrothermal. The relatively gentle thermal degradation of proteins allows the macromolecular structure of amino acids to be preserved. This preservation results in a more regular lattice structure, a larger sp2 domain size, and N-doping, which contribute to the highest quantum yield (QY) of 8.7% of the CDs. In contrast, cellulose undergoes more severe thermal degradation with large amounts of small molecules generated, resulting in the CDs with fewer surface defects, more irregular lattice structures, and lower QY. These results provide a guideline for the design of carbon dots from different biomass.

Poly(Lysine)-Derived Carbon Quantum Dots Conquer Enterococcus faecalis Biofilm-Induced Persistent Endodontic Infections.

Introduction: Persistent endodontic infections (PEIs) mediated by bacterial biofilm mainly cause persistent periapical inflammation, resulting in recurrent periapical abscesses and progressive bone destruction. However, conventional root canal disinfectants are highly damaging to the tooth and periodontal tissue and ineffective in treating persistent root canal infections. Antimicrobial materials that are biocompatible with apical tissues and can eliminate PEIs-associated bacteria are urgently needed. Methods: Here, ε-poly (L-lysine) derived carbon quantum dots (PL-CQDs) are fabricated using pyrolysis to remove PEIs-associated bacterial biofilms. Results: Due to their ultra-small size, high positive charge, and active reactive oxygen species (ROS) generation capacity, PL-CQDs exhibit highly effective antibacterial activity against Enterococcus faecalis (E. faecalis), which is greatly dependent on PL-CQDs concentrations. 100 µg/mL PL-CQDs could kill E. faecalis in 5 min. Importantly, PL-CQDs effectively achieved a reduction of biofilms in the isolated teeth model, disrupting the dense structure of biofilms. PL-CQDs have acceptable cytocompatibility and hemocompatibility in vitro and good biosafety in vivo. Discussion: Thus, PL-CQDs provide a new strategy for treating E. faecalis-associated PEIs.

Clinical Outcomes of Dental Implant Fractures: A Case Series and Analysis of Influencing Factors.

OBJECTIVE: To observe and analyse patients with dental implant fracture and explore the factors influencing the fracture with the aim of providing reference for physicians' clinical work. METHODS: The clinical data of 19 patients with dental implant fracture who visited the Department of Implantology of our hospital between 2007 and 2019 were retrospectively observed and analysed, and the fracture's influencing factors (e.g. the fracted implant site, implant diameter and connection mode, upper prosthetic method and fracture site) were analysed and investigated. RESULTS: The fractured implants comprised 12 Straumann implants (5 fractured at the smooth dental neck and 7 atop the central screws), 5 Bego implants (4 fractured at the smooth dental neck and 1 atop the central screw), 3 Lifecore implants fractured atop the central screws and 1 Anthogyr implant fractured atop the central screw. Of the 19 patients, 6 had anterior dental implant fracture, and 13 had posterior dental implant fracture (21 fractured implants in total). Maxillary anterior dental implant fracture was observed in 6 patients (8 implants), maxillary posterior implant fracture was observed in 3 patients (3 implants), and mandibular posterior dental implant fracture was observed in 10 patients (10 implants). CONCLUSIONS: A good implant system design, appropriate implant diameter and reasonable upper prosthetic method are key to maintaining long-term stability of a dental implant.

Salivary metabolomics of burning mouth syndrome: A cross-sectional study.

OBJECTIVE: There is a lack of systematic studies on salivary metabolomic profiles in burning mouth syndrome (BMS); metabolomics could help explore BMS pathogenesis. We aimed to explore the salivary metabolomic profile of patients with BMS using untargeted metabolomics techniques. DESIGN: A cross-sectional study was designed to analyze the characteristics of unstimulated whole salivary metabolomics of patients with BMS (n = 34) and healthy participants (n = 30). Ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry, principal component, orthogonal partial least-squares-discriminant, hierarchical clustering, and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed to identify differentially expressed metabolites and metabolic pathways in which they were enriched. RESULTS: We identified 12,982 metabolite ions. Among them, 394 differentially expressed metabolites were identified with variable importance in projection scores of > 1 (P < 0.05) compared with those in the controls. Based on the Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis, 30 metabolites were identified, and 16 of them were enriched in 25 metabolic pathways. The levels of caffeine (log2-fold change = -2.91) and its metabolites, paraxanthine (-2.01) and theophylline (-2.03), were low, and the caffeine metabolism pathway was downregulated in the BMS group compared with those in the controls (P < 0.05). CONCLUSIONS: The salivary metabolomic profile of patients with BMS presented characteristics distinct from those of the controls. A low caffeine level may be associated with BMS. This study provides a novel insight for further exploration of the pathogenesis of and potential therapeutic approaches for BMS.

Composite dissolvable microneedle patch for therapy of oral mucosal diseases.

A composite microneedle patch (MN patch) is developed for oral transmucosal administration. To improve the oral transmucosal drug delivery efficiency, the composite MN patch is designed to consist of an array of 100 dissolvable microneedles (MNs) with drug-loaded tips and a backing layer. The MNs are composed of two parts, the hyaluronic acid (HA) tip part and the polyvinylpyrrolidone (PVP) base part. Due to the small size and sufficient mechanical strength, the HA-PVP MNs can painlessly penetrate the oral mucosa barrier and deliver drugs directly to the basal layer or submucosa. Betamethasone sodium phosphate (BSP), as the model drug, is concentrated in the HA tip parts to avoid the drug waste caused by mucosa elasticity. Considering the special moist environment and saliva flow in the mouth, a double-layer backing layer composed of a poly(vinyl alcohol) (PVA) adhesive layer and an ethyl cellulose (EC) waterproof layer is designed and constructed, which could reduce the saliva flow effects. The in vitro and in vivo results demonstrate that the MN patch could achieve rapid and efficient BSP release in oral mucosa due to the rapid dissolution of HA. The proposed MN patch provides a novel strategy for the therapy of oral mucosal diseases.

Influence of periodontal treatment on blood microbiotas: a clinical trial.

OBJECTIVE: To investigate the effects of periodontal treatment on the abundance and diversity of blood microbiota. METHODS AND MATERIALS: Twenty-seven periodontitis patients were randomly allocated to a control group (A) and two test groups (B1 and B2). Group A patients received full-mouth scaling and root planing (SRP), group B1 patients received subgingival glycine air polishing (GAP) right after SRP, and group B2 patients received subgingival glycine air polishing right before SRP. Peripheral blood samples were obtained at the baseline, the day after periodontal treatment, and 6 weeks after treatment and evaluated using nested polymerase chain reaction and 16SrRNA Gene Sequencing (Miseq platform). RESULTS: All participants exhibited significant improvements in the clinical parameters evaluated at the 6-week follow-up visit compared to the values at the baseline, but no significant differences were observed between the three groups. The total bacterial count was lowest in group B2. The bacterial species diversity (α-diversity) in group B1 was significantly higher (Chao-1 index, P = 0.03) and Porphyromonas and Pantoea were the dominant genera (linear discriminant analysis (LDA > 2)) in this group the day after treatment compared to the baseline. No significant difference was detected in the relative abundance and α-diversity of blood microbiota between the baseline and 6 weeks after treatment. CONCLUSION: Local periodontal treatment merely disrupts the stability of blood microbiota in the short term. Periodontitis treatment using full-mouth SRP followed by adjunctive GAP is a promising approach to reduce the introduction of bacteria into the bloodstream during the procedure.

Rational Construction of a Mitochondrial Targeting, Fluorescent Self-Reporting Drug-Delivery Platform for Combined Enhancement of Endogenous ROS Responsiveness.

To maximize the utilization and response to the high oxidative stress environment of tumor sites while avoiding the dilemma of enhancing reactive oxygen species (ROS) response in a single way, mitochondrial targeting combined with fluorescent self-reporting polymeric nanocarriers (1K-TPP and 2K-TPP) with grafted structures were synthesized via a chemoenzymatic method in a high yield to simultaneously enhance the drug delivery of endogenous ROS responses. 1K-TPP and 2K-TPP loaded doxorubicin (DOX) at a high content over 12% and formed homogeneous spherical micelles. In vitro, both of them showed promising high sensitivity (detection limit below 200 nM H2O2), fast response, and ratiometric fluorescent self-reporting properties (fluorescent enhancement more than 200 times) to ROS and excellent stability under physiological conditions, while achieving a rapid release of the DOX in response to 1 mM H2O2. Cell co-localization experiments exhibited that they had favorable mitochondrial targeting, and mitochondrial isolation experiments also confirmed that the TPP-modified 1K-TPP selectively accumulated nearly three times in mitochondria than that in total cells. The internalization of 1K-TPP and 2K-TPP into cancer cells was greatly improved by nearly 200% compared to that of unmodified control (1K-OH and 2K-OH) and also explored a unique energy-dependent endocytosis. Furthermore, stimulation of endogenous ROS enhanced the green fluorescence intensity (up to 51.4%) of the linked probe so as to destroy the internal structure of the nanocarriers, achieving self-reporting of the drug's intracellular release and tracking of the intracellular location of nanocarriers. The cytotoxicity of DOX-loaded 1K-TPP and 2K-TPP in tumor cells with a higher ROS content showed statistical superiority to that of 1K-OH and 2K-OH, benefiting from the extremely good endogenous ROS response sensitivity leading to the differential selective release of drugs. These results demonstrate the potential of 1K-TPP and 2K-TPP, especially for 1K-TPP, as mitochondria-targeted, fluorescent self-reporting nanocarriers for combined enhancement of endogenous ROS responsiveness.

Controllable acidophilic dual-emission fluorescent carbonized polymer dots for selective imaging of bacteria.

Fluorescent materials can be powerful contrast agents in photoelectric devices and for bioimaging. As emerging fluorescent materials, carbonized polymer dots (CPDs) with high quantum yields (QYs), long-wavelength emission and multiple functions are highly desired. Despite great progress in the synthetic methods and QYs of CPDs, multiple emission of CPDs is challenging. Therefore, we developed CPDs with dual-emission fluorescence in terms of inherent blue and red emission. In addition, CPDs with sole blue emission (B-CPDs) and red emission (R-CPDs) were synthesized, respectively, by regulating the reaction conditions to control the quantitative structure and emission centers. The absolute QY of R-CPDs in water was 24.33%. These three types of CPDs with dual/sole emission could be used in optoelectronic and bioimaging applications. With different CPDs coated on a commercially available gallium nitride light-emitting diode chip as a color-conversion layer, LEDs with blue, yellow, and red emission were achieved. Benefiting from the different emission intensities and emission peaks of R/B-CPDs in different pH conditions, they were used (without further modification) to distinguish between Porphyromonas gingivalis, Streptococcus mutans, Escherichia coli and Staphylococcus aureus in dental plaque biofilms (the first time this has been demonstrated). These findings could enable a new development direction of CPDs based on the design of multi-emission centers.

[Maxillary first premolar with four canals: a case report].

This article presented a case of discovering and diagnosing three roots with four canals of the maxillary first premolar. We found and located the extra root canal by clinical diagnosis, careful observation during the operation, and multiangle X-ray. We further confirmed the existence of the three roots with four canals with the help of cone-beam computed tomography. Finally, we verified the success of the high-quality root-canal therapy through root optical microscopy.

Anti-inflammatory Effects of PMX205 in Mouse Macrophage Periodontitis Model.

BACKGROUND: C5a receptor antagonist PMX205 is a synthetic hexapeptide capable of blocking C5a-C5a receptor (C5aR) axis by simulating C5a active C-terminal amino acid residues. This hexapeptide presents good anti-inflammatory effects in a series of inflammation models. The anti-inflammatory effect of PMX205 on periodontitis is yet to be fully fathomed. OBJECTIVE: To examine the anti-inflammatory effects of PMX205 on RAW264.7 mouse macrophages exposed to gingipain extracts and Porphyromonas gingivalis (P. gingivalis). METHODS: MTT assay was carried out so as to specify the cytotoxicity of PMX205. RAW264.7 cells were co-cultured in vitro with gingipain extracts or P. gingivalis to simulate the periodontitis inflammatory milieu. Real-time quantitative PCR, ELISA and Griess assay were performed in order to detect tumor necrosis factor-α (TNF-α), IL-6, IL-23, nitric oxide (NO), IL-10, transforming growth factor-ß1 (TGF-ß1), andarginase-1 (Arg-1). Furthermore, phagocytosis assay was done to evaluate the phagocytic capacity of RAW 264.7 cells. Finally, western blot analysis was conducted to evaluate myeloid differentiation factor 88 (MyD88). RESULTS: PMX205 increased the expression levels of bacteriostatic substances (NO and IL-23) and anti-inflammatory cytokines (TGF-ß1, IL-10 and Arg-1); however, it reduced the expression levels of proinflammatory cytokines TNF-α and IL-6 once RAW 264.7 macrophages were stimulated via gingipain extracts or P. gingivalis. In addition, PMX205 promoted the macrophage phagocytosis and down-regulated protein expression of MyD88. CONCLUSION: PMX205 has recognizable anti-inflammatory effects in RAW 264.7 cell inflammation model, a finding which probably opens doors to future investigations on new targets for the prevention and treatment of chronic periodontitis.

The feasibility and application of PPy in cathodic polarization antifouling.

Cathodic polarization antifouling deserves attention because of its environmentally friendly nature and good sustainability. It has been proven that cathodic voltages applied on metal substrates exhibit outstanding antifouling effects. However, most metals immersed in marine environment are protected by insulated anticorrosive coatings, restricting the cathodic polarization applied on metals. This study developed a conducting polypyrrole (PPy)/acrylic resin coating (σ = 0.18 Scm-1), which can be applied in cathodic polarization antifouling. The good stability and electro-activity of PPy in the negative polarity zone in alkalescent NaCl solution were verified by linear sweep voltammetry (LSV), chronoamperometry (CA), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), demonstrating the feasibility of PPy as cathodic polarization material. Furthermore, the antifouling effects of PPy/acrylicresin coating on 24-h old Escherichia coli bacteria (E. coli) which formed on PPy/acrylic resin-coated plastic plate were measured under different cathodic potentials and treatment time, characterized by fluorescent microscope. The results suggest that at cathodic potential around -0.5 V (vs. saturated calomel electrode (SCE)), there was little trace of attached bacteria on the substrate after 20 min of treatment. PPy/acrylicresin-coated substrates were also subjected to repeated cycles of biofilm formation and electrochemical removal, where high removal efficiencies were maintained throughout the total polarization process. Under these conditions, the generation of hydrogen peroxide is believed to be responsible for the antifouling effects because of causing oxidative damage to cells, suggesting the potential of the proposed technology for application on insulated surfaces in various industrial settings.

The biomechanical impact of facet tropism on the intervertebral disc and facet joints in the cervical spine.

BACKGROUND CONTEXT: Facet tropism is defined as the angular difference between the left and the right facet orientation. Facet tropism was suggested to be associated with the disc degeneration and facet degeneration in the lumbar spine. However, little is known about the relationship between facet tropism and pathologic changes in the cervical spine and the mechanism behind. PURPOSE: This study was conducted to investigate the biomechanical impact of facet tropism on the intervertebral disc and facet joints. STUDY DESIGN: A finite element analysis study. METHODS: The computed tomography (CT) scans of a 28-year-old male volunteer was used to construct the finite element model. First, a symmetrical cervical model from C2 to C7 was constructed. The facet orientations at each level were simulated using the data from our previously published study. Second, the facet orientations at the C5-C6 level were altered to simulate facet tropism with respect to the sagittal plane. The angular difference of the moderate facet tropism model was set to be 7 degrees, whereas the severe facet tropism model was set to be 14 degrees. The inferior of the C7 vertebra was fixed. A 75 N follower loading was applied to simulate the weight of the head. A 1.0 N⋅m moments was applied on the odontoid process of the C2 to simulate flexion, extension, lateral bending, and axial rotation. RESULTS: The intradiscal pressure (IDP) at the C5-C6 level of the severe facet tropism model increased by 49.02%, 57.14%, 39.06%, and 30.67%, under flexion, extension, lateral bending, and axial rotation moments, in comparison with the symmetrical model. The contact force of the severe facet tropism model increased by 35.64%, 31.74%, 79.26%, and 59.47% from the symmetrical model under flexion, extension, lateral bending, and axial rotation, respectively. CONCLUSIONS: Facet tropism with respect to the sagittal plane at the C5-C6 level increased the IDP and facet contact force under flexion, extension, lateral bending, and axial rotation. The results suggested that facet tropism might be the anatomic risk factor of the development of cervical disc degeneration or facet degeneration. Future clinical studies are in need to verify the biomechanical impact of facet tropism on the development of degenerative changes in the cervical spine.

Β-cyclodextrin polymer as a linker to fabricate ternary nanocomposites AuNPs/pATP-ß-CDP/rGO and their electrochemical application.

Based on the self-assembly strategy, ß-cyclodextrin polymer (ß-CDP) was used as a linker to connect reduced graphene oxide (rGO) and p-aminothiophenol (pATP). Then, pre-prepared gold nanoparticles (AuNPs) can self-assemble onto the surface of pATP-ß-CDP/rGO to obtain new ternary nanocomposites AuNPs/pATP-ß-CDP/rGO. The amount or the density of AuNPs can be adjusted by changing the concentration of pATP. UV-vis and (1)H NMR spectra confirmed the formation of inclusion complex between pATP and ß-CDP. ß-CDP might improve the dispersity of rGO in aqueous and the surface property of rGO. AuNPs/pATP-ß-CDP/rGO modified electrode displayed high electrochemical response toward a pesticide-imidacloprid (IDP). The enrichment capability and molecular recognition of ß-CDP and the catalytic property of AuNPs for IDP molecules synergistically promoted the electrochemical response of rGO modified electrode. Additionally, ternary nanocomposites exhibited the good electrocatalytic performance for oxygen reduction in O2-saturated 0.1M H2SO4 solution. The proposed synthesis strategy provided a facile, feasible and effective method for development of electrochemical sensors and Au-based catalysts for fuel cells.

Synthesis of Substituted Benzenes via Bi(OTf)3-Mediated Intramolecular Carbonyl Allylation of α-Prenyl or α-Geranyl ß-Arylketosulfones.

Intramolecular carbonyl allylation of α-prenyl or α-geranyl ß-arylketosulfones 5 in the presence of molecule sieves (MS) affords substituted benzenes 6-7 in moderate to good yields. The facile transformation proceeds by a synthetic sequence starting with the α-prenylation or α-geranylation of 1 and the Bi(OTf)3-mediated annulation of 5 followed by a sequential desulfonative aromatization or then an intramolecular Friedel-Crafts alkylation. A plausible mechanism has been studied and proposed.

Polyphosphoric acid promoted synthesis of 10,11-dihydrobenzo[j]fluoranthen-12-one.

A straightforward synthesis of 3,8-dimethoxy-10,11-dihydrobenzo[j]fluoranthen-12-ones 1 is reported in a seven-step route from biphenyl-4,4'-diol 2 via the transformation of a double Claisen rearrangement, cross metathesis with ethyl acrylate, and polyphosphoric acid (PPA)-promoted Friedel-Crafts electrophilic benzannulation in good yields.