[Retention after orthodontic treatment].

In general, the result of orthodontic treatment is not stable. After active treatment, changes can occur as a result of a number of biological processes. The application of retention aims to counteract such changes and thereby preserve the result of orthodontic treatment.

[Orthodontic retention: problems and problem-solving strategies].

The aim of orthodontic retention is to counteract post-treatment changes and thereby to preserve the result of active treatment. For active orthodontic treatment, a certain level of patient compliance is necessary and the same applies for the retention phase. Ideally, the retainer will never fail or get lost, the patient will adhere to all recommendations and will wear the retainer in accordance with the instructions, necessary precautions with the fixed retainer are followed, the patient reports a problem immediately, and appointments for retention check-ups will always be met.

N-Heterocyclic Carbenes Reduce and Functionalize Copper Oxide Surfaces in One Pot.

Benzimidazolium hydrogen carbonate salts have been shown to act as N-heterocyclic carbene precursors, which can remove oxide from copper oxide surfaces and functionalize the resulting metallic surfaces in a single pot. Both the surfaces and the etching products were fully characterized by spectroscopic methods. Analysis of surfaces before and after NHC treatment by X-ray photoelectron spectroscopy demonstrates the complete removal of copper(II) oxide.

N-heterocyclic carbene-functionalized magic-number gold nanoclusters.

Magic-number gold nanoclusters are atomically precise nanomaterials that have enabled unprecedented insight into structure-property relationships in nanoscience. Thiolates are the most common ligand, binding to the cluster via a staple motif in which only central gold atoms are in the metallic state. The lack of other strongly bound ligands for nanoclusters with different bonding modes has been a significant limitation in the field.

Epidemiologic study of orthodontic retention procedures.

Introduction: The aims of this study were to survey current retention procedures applied by Dutch orthodontists and to examine their acquaintance with "unintentionally active retainers."

Methods: A questionnaire was sent to all 306 Dutch orthodontists involved in patient treatment. Questions were clustered in 4 parts: (1) general information, (2) retention procedures, (3) characteristics of wire materials for bonded retainers, and (4) acquaintance with "unintentionally active retainers.