RESUMEN
Experimental light-curing pattern resins were fabricated to produce pattern resin materials with adequate dimensional stability. The light-curing pattern resins consisted of poly(n-butyl methacrylate) or poly(iso-butyl methacrylate) (PiBMA) polymers and methacrylate monomers. The physical properties, amount of residual ash after burning, Vickers hardness, flexural strength, and volumetric polymerization shrinkage of each material were determined. The data obtained for the prepared resins were compared with those of a commercially available pattern resin, Palavit G (PG). A lower amount of residual ash was observed for some of the prepared resins than for PG. The Vickers hardness and flexural strength values of all experimental resins were lower than those of PG. The volumetric polymerization shrinkage of all the experimental resins based on PiBMA was lower than that of PG. These results suggest that acrylic light-curing resin materials based on PiBMA may be useful for patterning and indexing during soldering.
Asunto(s)
Resistencia Flexional , Dureza , Ensayo de Materiales , Metacrilatos , Polimerizacion , Propiedades de Superficie , Metacrilatos/química , Curación por Luz de Adhesivos Dentales , Resinas Compuestas/química , Resinas Compuestas/efectos de la radiación , Luces de Curación Dental , Resinas Acrílicas/químicaRESUMEN
Background: Positron emission tomography, which assesses the binding of translocator protein radiotracers, 11C-DPA-713, may be a sensitive method for determining glial-mediated neuroinflammation levels. This study investigated the relationship between regional 11C-DPA713 binding potential (BPND) and anxiety in patients with Alzheimer's disease (AD) continuum. Methods: Nineteen patients with AD continuum determined to be amyloid-/p-tau 181-positive via cerebrospinal fluid analysis were included in this cross-sectional study (mild cognitive impairment [MCI, n = 5] and AD [n = 14]). Anxiety was evaluated using the State-Trait Anxiety Inventory (STAI). A whole-brain voxel-based analysis was performed to examine the relationship between 11C-DPA-713-BPND values at each voxel and the STAI score. Stepwise multiple regression analysis was performed to determine the predictors of STAI scores using independent variables, including 11C-DPA-713-BPND values within significant clusters. 11C-DPA-713-BPND values were compared between patients with AD continuum with low-to-moderate and high STAI scores. Results: Voxel-based analysis revealed a positive correlation between trait anxiety severity and 11C-DPA713-BPND values in the centromedial amygdala and the left inferior occipital area [P < 0.001 (uncorrected) at the voxel-level]. 11C-DPA713-BPND values in these regions were a strong predictor of the STAI trait anxiety score. Specifically, patients with AD continuum and high trait anxiety had increased 11C-DPA713-BPND values in these regions. Conclusions: The amygdala-occipital lobe circuit influences the control of emotional generation, and disruption of this network by AD pathology-induced inflammation may contribute to the expression of anxiety. Our findings suggest that suppression of inflammation can help effectively treat anxiety by attenuating damage to the amygdala and its associated areas.