Analytical determination of the Landau-Ginzburg parameters of (100) metal homoepitaxial systems

In the initial stages of homoepitaxial growth on the (100) surface of metals such as Ag, Fe, Cu, Ni, and Pd, where the clean surface does not reconstruct, two-dimensional islands with compact, near-square shapes are formed. In order to determine the phenomenological material parameters of the nonlinear and nonlocal Landau-Ginzburg theory, which describes the metal homoepitaxial systems mentioned above, an atomistic model for these systems is developed. Based on this model, we derive analytical relationships between the Landau-Ginzburg parameters A, B, C, and D, and the parameters of the homoepitaxial system (such as coverage, first-neighbour interaction energy, etc.). We find that the Landau-Ginzburg parameters of the system depend on the specific material as well as on the coverage of the surface. We then apply the method to the Ag/Ag(100) system. Copyright EDP Sciences/Società Italiana di Fisica/Springer-Verlag 200668.47.De Metallic surfaces, 61.50.Ah Theory of crystal structure, crystal symmetry; calculations and modeling, 64.60.Qb Nucleation,

Patient experience of autogenous soft tissue grafting has an implication for future treatment: A 10‐ to 15‐year cross‐sectional study

BackgroundPatient- reported outcomes have received a great deal of interest in periodontal plastic procedures. However, their evaluation has mainly been short- term. Thus, the aim of this study was to evaluate the impact of soft tissue grafting procedures conducted over a decade ago on the willingness of a patients to undergo the surgery again.MethodsSubjects that received an autogenous soft tissue graft over 10 years ago were screened and invited for a survey. Their response was only analyzed if they were able to correctly identify the sites of the surgical procedures. Dichotomous questions and visual analogue scales (VASs) were used to assess self- reported pain, willingness to retreat and satisfaction.ResultsFifty- two patients were included in the analyses. Higher pain was reported for mandibular sites, and treated areas including - ¥ 3 teeth (P < 0.01). Willingness to retreatment was 84.6% and it was negatively associated with self- reported pain measures, the arch location (mandible), and number of treated sites (- ¥3 teeth) (P < 0.01). Mean satisfaction rate was 86.9 ± 13.65 (VAS) and showed a positive correlation with willingness to retreat (P < 0.01). Having a complete root coverage at the recall visit was also significantly associated with higher patient satisfaction scores (P < 0.01).ConclusionsPatient experience of previous autogenous soft tissue grafting has an influence on their decision to undergo future treatment. Willingness to retreat was negatively affected by mandibular sites, larger treated areas and the perceived pain, while presenting with complete root coverage was significantly associated with patient satisfaction.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/167778/1/jper10653_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/167778/2/jper10653.pd

Development and international validation of logistic regression and machine-learning models for the prediction of 10-years molar loss

To develop and validate logistic regression and artificial-intelligence based models for prognostic prediction of molar survival in periodontally-affected patients

Long term comparison of the prognostic performance of PerioRisk, periodontal risk assessment, periodontal risk calculator, and staging and grading systems

BackgroundClinicians predominantly use personal judgment for risk assessment. Periodontal risk assessment tools (PRATs) provide an effective and logical system to stratify patients based on their individual treatment needs. This retrospective longitudinal study aimed to validate the association of different risk categories of four PRATs (Staging and grading; Periodontal Risk Assessment (PRA); Periodontal Risk Calculator; and PerioRisk) with periodontal related tooth loss (TLP), and to compare their prognostic performance.MethodsData on medical history, smoking status, and clinical periodontal parameters were retrieved from patients who received surgical and non- surgical periodontal treatment. A comparison of the rate of TLP and non- periodontal related tooth loss (TLO) within the risk tool classes were performed by means of Kruskal- Wallis test followed by post- hoc comparison with the Bonferroni test. Both univariate and multivariate Cox Proportional hazard regression models were built to analyze the prognostic significance for each single risk assessment tool class on TLP.ResultsA total of 167 patients with 4321 teeth followed up for a mean period of 26 years were assigned to four PRATs. PerioRisk class 5 had a hazard ratio of 18.43, Stage 4 had a hazard ratio of 7.99, and PRA class 3 had a hazard ratio of 6.13 compared with class/stage I. With respect to prognostic performance, PerioRisk tool demonstrated the best discrimination and model fit followed by PRA.ConclusionAll PRATs displayed very good predictive capability of TLP. PerioRisk showed the best discrimination and model fit, followed by PRA.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/171568/1/jper10773_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/171568/2/jper10773.pd