Factors Influencing Non-Surgical Root Canal Treatment Outcomes in Mandibular Second Molars: A Retrospective Cone-Beam Computed Tomography Analysis.

Background/Objectives: This study aimed to investigate the influence of the root canal morphology and various treatment variables on the outcomes of root canal treatments (RCTs) in mandibular second molars, assessed through cone-beam computed tomography (CBCT) imaging. Methods: A total of 150 CBCT images were examined, comprising 100 cases of persistent endodontic infections and 50 of previously treated root canals with normal apices in the mandibular second molars. CBCT was utilized to evaluate the root canal configuration, the radiographic quality of coronal restorations and treated canal systems, and the presence of periapical lesions. Statistical analyses were performed to explore the correlations between these factors. Results: The presence of a C-shaped root canal configuration did not demonstrate a significant correlation with periapical lesions (p = 0.05). Factors influencing endodontic treatment outcomes included missing canals (p = 0.018), underfilling or overfilling (p = 0.045), and inadequate coronal restoration (p = 0.006). Missing a canal was identified as the variable most significantly associated with periapical lesions (OR = 3.103). Inhomogeneous root canal obturation was more commonly observed in C-shaped root canals (p < 0.001). Conclusions: Regardless of the root canal morphology of mandibular second molars, successful RCT depends on thorough disinfection to eliminate any untreated canals, precise three-dimensional filling of the canals at the correct working length, and a securely sealed coronal restoration to prevent leakage.

Influence of smoking history on the perception of radiation-induced dysgeusia/hypogeusia in patients with head and neck cancer.

OBJECTIVES: This investigation aimed to assess the effect of smoking on the onset and resolution of dysgeusia/hypogeusia in head and neck cancer (HNC) patients receiving radiotherapy (XRT). MATERIALS AND METHODS: This is a retrospective cohort investigation of HNC patients treated with XRT. Data collected from the patients' medical records included demographics, primary cancer diagnoses, HNC therapeutic modalities, smoking status, and dates of onset/resolution of dysgeusia/hypogeusia. RESULTS: A 103 met inclusion criteria, of which 61.8% developed dysgeusia/hypogeusia. Mean age was 58.3 ± 12.9 and 66% were either former or current smokers. Never smokers seemed to be at higher, but statistically insignificant, the risk for developing dysgeusia/hypogeusia than former or current smokers [HR 1.05 and 1.66; 95% CI (0.60, 1.84) and (0.85, 3.24)]. They were also less likely to recover when compared to former smokers [HR 0.74; 95% CI (0.39, 1.39)]. Although statistically insignificant, never smokers showed rapid dysgeusia/hypogeusia onset after XRT compared to former or current smokers (median 14 days versus 22 and 9 days, respectively; p = 0.25). Never smokers showed quicker but statistically insignificant, recovery time compared to former or current smokers (median 113 days versus 149 and 238 days, respectively; p = 0.57). CONCLUSION: Although results lacked statistical significance, never smokers receiving XRT were prone to higher risk and faster onset of dysgeusia/hypogeusia than former and current smokers.

Sex-related dimorphism in dentate gyrus atrophy and behavioral phenotypes in an inducible tTa:APPsi transgenic model of Alzheimer's disease.

Sex differences are a well-known phenomenon in Alzheimer's disease (AD), with women having a higher risk for AD than men. Many AD mouse models display a similar sex-dependent pattern, with females showing earlier cognitive deficits and more severe neuropathology than males. However, whether those differences are relevant to human disease is unclear. Here we show that in AD mouse models that overexpress amyloid precursor protein (APP) under control of the prion protein promoter (PrP), female transgenic mice have higher APP expression than males, complicating interpretations of the role of sex-related factors in such models. By contrast, in a tTa:APPsi model, in which APP expression is driven by the tetracycline transactivator (tTa) from the CaMKIIα promoter, there are no sex-related differences in expression or processing of APP. In addition, the levels of Aß dimers and tetramers, as well as Aß peptide accumulation, are similar between sexes. Behavioral testing demonstrated that both male and female tTa:APPsi mice develop age-dependent deficits in spatial recognition memory and conditional freezing to context. These cognitive deficits were accompanied by habituation-associated hyperlocomotion and startle hyper-reactivity. Significant sex-related dimorphisms were observed, due to females showing earlier onsets of the deficits in conditioned freezing and hyperlocomotion. In addition, tTa:APPsi males but not females demonstrated a lack of novelty-induced activation. Both males and females showed atrophy of the dentate gyrus (DG) of the dorsal hippocampus, associated with widening of the pyramidal layer of the CA1 area in both sexes. Ventral DG was preserved. Sex-related differences were limited to the DG, with females showing more advanced degeneration than males. Collectively, our data show that the tTa:APPsi model is characterized by a lack of sex-related differences in APP expression, making this model useful in deciphering the mechanisms of sex differences in AD pathogenesis. Sex-related dimorphisms observed in this model under conditions of equal APP expression between sexes suggest a higher sensitivity of females to the effects of APP and/or Aß production.

Fabrication of Mesoporous Carbon Tube and Foam: Application as Supports in Enantio-Selective Separation of Optically Pure Amino Acid from Racemates.

The mesoporous monolithic carbon (MMC) foams and carbon tubes were newly fabricated in cm-scale using the mixture of triblock copolymers and phenol/HCHO resin precursors. The regular mesoporosity were formed in the body of MMC foam and carbon fibers. In this work, the organic phases containing chiral ARCA adsorbent and a phase transfer catalyst were coated on the surfaces of mesoporous carbon support, and this ARCA/carbon mixture was adopted for the enantioselective separation of amino acid in the circulation system. (S)-ARCA coated MMC support showed high selcetivity up to 90% for the separation of D-type phenylalanine, serine and tryptophan from racemic mixtures.