RESUMEN
RutheniumII complexes bearing three axially chiral bipyridyl ligands were synthesized as a new family of chiral complex dyes, and Δ-(S)- and Λ-(S)-diastereomers were obtained. The X-ray crystal structure analyses, spectroscopy, and DFT calculations suggested that all the bipyridyls maintained chirality in both the ground and excited states, and the Δ-(S)- and Λ-(S)-isomers are the matched (more relaxed) and mismatched (more constrained) pairs, respectively. The mismatched Λ-(S)-isomer exhibited red circularly polarized phosphorescence (CPP) both in solution and in the solid state. The solution state CPP is the most intense of ruthenium complexes, while the solid state CPP is the first example of them. It is supposed that, for the Λ-(S)-isomer, the six cumulative CH/π interactions suppress further distortion in the T1 state.
Asunto(s)
Rutenio , 2,2'-Dipiridil , Isomerismo , Ligandos , Análisis EspectralRESUMEN
The purpose of this study was to investigate which were the most important factors in determining the location of the main occluding area by comparing its site on the dental arch between patients treated with implant-supported prostheses and those with a shortened dental arch (SDA). Twenty-five patients with Eichner B1 occlusion were enrolled in the study. The molar region in each quadrant was always edentulous. Fifteen patients were treated with implant prostheses, while the remaining 10 patients had SDA. Each patient was instructed to clench a piece of temporary stopping in the occluding area that was preferably used during mastication. The main occluding area was determined by locating the tooth on which the temporary stopping rested during clenching. The main occluding area was located ipsilaterally to the edentulous side in the molar region more often in the implant patients than in the SDA patients. The results of the present study suggest that the most important factor in determining the main occluding area is the presence of bilateral rigid molar occlusal support.
Asunto(s)
Arco Dental , Oclusión Dental , Arcada Parcialmente Edéntula , Prótesis Dental de Soporte Implantado , Humanos , Masticación , Diente MolarRESUMEN
PURPOSE: Many studies have reported the relationship between facial morphology and stomatognathic functions. The steepness of the articular eminence is an important morphological factor to determine the mandibular movement or mandibular positioning. The present study analyzed the relationship between the condylar displacement during clenching and the condylar guide inclination related to simulated loss of posterior occlusal support. METHODS: Nineteen clinical residents (4 females and 15 males, 24-31 years old) with healthy natural dentitions were recruited as subjects. To change the posterior occlusal support, occlusal splints fitted to maxillary dental arches were cut in sequence from the posterior toward the anterior side. The condylar displacements during maximum voluntary clenching under every occlusal condition were measured using a mandibular movement analyzing system with six-degrees of freedom. The sagittal condylar guide inclination was also measured using the same apparatus. RESULTS: 1. A greater loss of posterior occlusal support was associated with increased displacement distance of both condyles, however these values varied with the subject. 2. A significant positive correlation was observed between the displacement distance without splint and the relative displacement distance with splint (difference between before and after loss of occlusal supports). 3. A significant negative correlation was observed between the displacement distance without splint and the sagittal condylar guide inclination, and was also observed between the relative displacement distance with splint (above-mentioned) and the sagittal condylar guide inclination. CONCLUSION: These results suggest that the sagittal condylar guide inclination is an important factor in condylar displacement during clenching.