1. |
- Brodén, Joséphine, et al.
(författare)
-
Direct pulp capping procedures versus root canal treatment in young permanent vital teeth with pulp exposures due to caries : A systematic review
- 2016
-
Ingår i: American Journal of Dentistry. - : Mosher & Linder. - 0894-8275. ; 29:4, s. 201-206
-
Forskningsöversikt (refereegranskat)abstract
- Purpose: To evaluate the available evidence on pulp capping procedures and root canal treatment in young permanent teeth with vital pulps exposed by caries. Methods: The study was conducted as a systematic review of the literature. Three databases, PubMed, Web of Knowledge, and The Cochrane Library were searched. Reference lists of relevant articles were hand searched. The quality of all relevant publications was rated. Results: Ten original scientific studies were included in the review. The quality was rated as low in all studies. The search failed to disclose any article directly comparing pulp capping and root canal treatment. The level of evidence was insufficient to draw any conclusions regarding the effectiveness of the two treatment concepts. High success rates are reported for pulp capping procedures in exposure due to caries, though it is not possible to compare them to success rates of root canal treatment. The review confirms the lack of high quality studies on the treatment of young permanent teeth with cariously exposed pulps.
|
|
2. |
- Schalk, Oliver, et al.
(författare)
-
Dissociation kinetics of excited ions : PEPICO measurements of Os-3(CO)(12) - The 7-35 eV single ionization binding energy region
- 2018
-
Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 148:8
-
Tidskriftsartikel (refereegranskat)abstract
- In this article, we study the photoinduced dissociation pathways of a metallocarbonyl, Os-3(CO)(12), in particular the consecutive loss of CO groups. To do so, we performed photoelectron-photoion coincidence (PEPICO) measurements in the single ionization binding energy region from 7 to 35 eV using 45-eV photons. Zero-energy ion appearance energies for the dissociation steps were extracted by modeling the PEPICO data using the statistical adiabatic channel model. Upon ionization to the excited ionic states above 13 eV binding energy, non-statistical behaviorwas observed and assigned to prompt CO loss. Double ionization was found to be dominated by the knockout process with an onset of 20.9 similar to 0.4 eV. The oscillator strength is significantly larger for energies above 26.6 similar to 0.4 eV, corresponding to one electron being ejected from the Os3 center and one from the CO ligands. The cross section for double ionization was found to increase linearly up to 35 eV ionization energy, at which 40% of the generated ions are doubly charged.
|
|
3. |
- Schalk, Oliver, et al.
(författare)
-
Ionization and photofragmentation of Ru-3(CO)(12) and Os-3(CO)(12)
- 2015
-
Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 143:15
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, we use a combination of photoelectron spectroscopy, mass spectrometry, and density functional theory calculations to get a detailed understanding of valence single and double ionization and the subsequent dissociation processes. This is exemplified on benchmark systems, trimetallo-dodecacarbonyls M-3(CO)(12) with M = Ru, Os, where the energy remaining in the molecule after photoionization can be retrieved by measuring the degree of fragmentation of the molecular ion. The intensity of different mass peaks can thus be directly related to ionization cross sections obtained by photoelectron spectroscopy. We find that the M-CO dissociation energy rises as the number of CO ligands decreases due to dissociation. Moreover, ionization of the CO ligands has a higher cross section than that of the metal center for both single and double ionization. After advanced fragmentation, a CO bond can break and the carbon atom remains bonded to the metal core. In addition, we found that the valence ionization cross sections of M-3(CO)(12) are maximal at about 40 eV photon energy thus showing a more pronounced shape resonance than Ru and Os-complexes with a single metal atom center. Finally, an np. nd giant resonance absorption causes a significant increase of the ionization cross section above 50 eV for Ru-3(CO)(12).
|
|