27 research outputs found
State of the science on controversial topics: orthodontic therapy and gingival recession (a report of the Angle Society of Europe 2013 meeting).
BACKGROUND: Controversy exists in the literature between the role of orthodontic treatment and gingival recession. Whilst movement of teeth outside the alveolar bone has been reported as a risk factor for gingival recession, others have found no such association. FINDINGS: The Angle Society of Europe devoted a study day to explore the evidence surrounding these controversies. The aim of the day was for a panel of experts to evaluate the current evidence base in relation to either the beneficial or detrimental effects of orthodontic treatment on the gingival tissue. CONCLUSIONS: There remains a relatively weak evidence base for the role of orthodontic treatment and gingival recession and thus a need to undertake a risk assessment and appropriate consent prior to the commencement of treatment. In further prospective, well designed trials are needed
Bovine pericardium based non-cross linked collagen matrix for successful root coverage, a clinical study in human
Introduction: The aim of this study was to clinically assess the capacity of a novel bovine pericardium based, non-cross linked collagen matrix in root coverage.
Methods: 62 gingival recessions of Miller class I or II were treated. The matrix was adapted underneath a coronal repositioned split thickness flap. Clinical values were assessed at baseline and after six months.
Results: The mean recession in each patient was 2.2 mm at baseline. 6 Months after surgery 86.7% of the exposed root surfaces were covered. On average 0,3 mm of recession remained. The clinical attachment level changed from 3.5 ± 1.3 mm to 1,8 ( ± 0,7) mm during the observational time period. No statistically significant difference was found in the difference of probing depth. An increase in the width of gingiva was significant. With a baseline value of 1.5 ± 0.9 mm an improvement of 2.4 ± 0.8 mm after six month could be observed. 40 out of 62 recessions were considered a thin biotype at baseline. After 6 months all 62 sites were assessed thick.
Conclusions: The results demonstrate the capacity of the bovine pericardium based non-cross linked collagen matrix for successful root coverage. This material was able to enhance gingival thickness and the width of keratinized gingiva. The percentage of root coverage achieved thereby is comparable to existing techniques. This method might contribute to an increase of patient's comfort and an enhanced aesthetical outcome
Interphase of a polymer at a solid interface
Atomistic molecular dynamics simulations of a chemically realistic model of atactic short-chain polystyrene between gold surfaces (111) and Positron Annihilation Lifetime Spectroscopy experiments on similar polystyrene thin films on gold were performed. Results from both approaches show that the free volume voids in the film have a slightly smaller average size than in bulk polystyrene. In agreement to that the existence of an interphase of higher density at the polymer-solid substrate interface is shown both by the simulation as well as in the experiment. The average shape of the voids is similar in the bulk and the film
Interphase of a Polymer at a Solid Interface
Atomistic
molecular dynamics simulations of a chemically realistic
model of atactic short-chain polystyrene between gold surfaces (111)
and positron annihilation lifetime spectroscopy experiments on similar
polystyrene thin films on gold were performed. Results from both approaches
show that the free volume voids in the film have a slightly smaller
average size than in bulk polystyrene. In agreement to that the existence
of an interphase of higher density at the polymer–solid substrate
interface is shown both by the simulation as well as in the experiment.
The average shape of the voids is similar in the bulk and the film