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BACKGROUND/AIM: Mandibular condylar fractures in pediatric patients may exhibit distinct epidemiological characteristics attributed to their unique growth and development phase, as well as various anatomical, physiological, biomechanical, and behavioral factors that differentiate them from adults. This study aimed to investigate the demographics, injurious factors, classifications, clinical manifestations, and treatments of pediatric mandibular condylar fractures, as well as the concomitant injuries in maxillofacial and other body parts. MATERIALS AND METHODS: This retrospective study analyzed the clinical data of 189 pediatric patients with mandibular condylar fractures between 2011 and 2022. Variables investigated included age, gender, timing of onset, causes, classification of condylar fracture, concomitant injuries, clinical manifestations, and treatment modalities. RESULTS: A total of 189 patients, a higher proportion of boys compared to girls was observed, with the highest incidence rate in children aged 1-3 years. They occurred primarily in July, June, and September as well as on Saturdays and Sundays. The most prevalent cause of mandibular condylar fractures was falls from heights in 73 patients (38.62%). Pediatric patients exhibited a higher susceptibility to condylar head fractures. A significant majority (81.48%) of these fractures were accompanied by soft tissue injuries in the maxillofacial region, with the chin being particularly vulnerable to injury. In addition, 61.90% of pediatric patients experienced fractures in other areas of the maxillofacial region, with the mandibular symphysis being the most commonly affected site. Dental trauma predominantly occurred in the anterior region (44.97%). Notably, a substantial proportion (28.04%) of cases also presented with multiple systemic injuries. CONCLUSIONS: The characteristics of pediatric mandibular condylar fractures exhibit distinct features in terms of age, gender, timing of onset, etiology, location and type, the presence of concomitant maxillofacial soft/hard tissue injuries and multiple systemic injuries, as well as clinical manifestations and treatment modalities. Therefore, clinicians should pay special attention to the diagnosis and treatment of pediatric condylar fractures.

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Photocatalysis under mild conditions is an intriguing avenue for organic chemical manufacturing to confront the serious fossil energy crisis. Herein, we report a direct light-driven alkene production through alcohol dehydration, using nonstoichiometric tungsten oxide of W18O49 nanowires with abundant lattice defects as a photocatalyst. A representative ethylene (C2H4) production rate of 275.5 mmol gcat -1 h-1 is achieved from ethanol (C2H5OH) dehydration, together with excellent selectivity up to 99.9%. The universality of our approach is further demonstrated with other alcohol dehydration. Combining ultrafast transient absorption spectroscopy with in situ X-ray photoelectron spectroscopy, we underline that the inter- and intraband transitions synergistically contribute to such excellent activity. In particular, the intraband transition excites the electrons in defect bands into an energetically "hot" state, largely alleviating the charge recombination. As a result, the C-OH bond of chemisorbed C2H5OH molecules can be effectively dissociated to furnish the formation of C=C bonds. Our work offers a fresh insight into sustainable alkene production with renewable energy input under mild conditions.

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OBJECTIVE: To assess the ultrastructural change of demineralized dentin collagen during calcium phosphate polymer-induced liquid precursor (Ca/P-PILP) mediated remineralization process and to evaluate the biomimetic remineralization potential of high concentration Ca/P-PILP at demineralized artificial caries dentin lesion, additionally to investigate the bond interfacial integrity as well as the bonding strength of the biomimetic remineralized artificial caries dentin lesion. METHODS: Demineralized dentin collagen of 5 µm thick was biomimetically remineralized with low, medium concentration Ca/P-PILP for 10 days and high concentration Ca/P-PILP for 10, 15, 20 days. Artificial caries dentin lesion at a thickness of 150 ± 50 µm was biomimetically remineralized with high concentration Ca/P-PILP for 20 days. The biomimetic remineralization of demineralized dentin collagen was observed by scanning electron microscopy (SEM). The biomimetic remineralization intensity and depth of artificial caries dentin lesion was assessed by Electron Probe Micro Analyzer (EPMA). The bonding interfacial integrity between remineralized artificial caries dentin and composite resin was observed by Swept-source optical coherence tomography (SS-OCT) and the bonding strength of remineralized artificial caries dentin was evaluated by micro-tensile bond strength analysis (µTBS). RESULTS: Solely PAA-PASP solution and solely saturated Ca/P solution can't achieve dentin collagen remineralization. Increased concentration of Ca/P-PILP and prolonged remineralization time can enhance the biomimetic remineralization intensity of demineralized dentin collagen. After treating with high concentration Ca/P-PILP, a 150 ± 50 µm thick layer of demineralized artificial caries dentin lesion was not fully remineralized, and the biomimetic remineralization intensity reached up to 88.0%. Furthermore, a better bonding interfacial integrity with less microgap and increased bond strength at both baseline level and aging level were observed when artificial caries dentin lesion was biomimetically remineralized with high concentration Ca/P-PILP. SIGNIFICANCE: Biomimetic remineralization of demineralized caries dentin lesion promotes its clinical properties for resin composited adhesive restoration.

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