Retentive characteristics of Ankylos SynCone conical crown system over long-term use in vitro.

18 Ankylos SynCone conical crowns with 4-degree angle and 18 SynCone conical crowns with 6-degree angle were tested in vitro for a total of 5,000 insertion-separation cycles to investigate their retentive characteristics. Under 20 N insertion force, the retentive force of Ankylos SynCone conical crown system was between 5 and 10 N. The rententive force kept almost constant during the entire testing cycles.

[Quality of the bristle-end rounding in ten brands of children's toothbrushes].

Animal and clinical studies have shown that sharp, unpolished toothbrush bristles may injure gingival tissue, and their contribution to cervical abrasion is widely discussed. The aim of the present study was to compare the end-roundness and smoothness of the bristle tips of ten commercially available children's toothbrushes (Elmex Lernzahnbürste, Aronal Oko Dent Kinder, Signal Kids, Dr. Best Milchzahn, Dr.