Approximately 1/2 of maxillary and 1/5 of mandibular multi-stranded lingual retainers fail during retention in some form, either bond failure or wire breakage. Memotain is a new CAD/CAM fabricated lingual retainer wire made of custom-cut nickel-titanium, as an alternative to multi-stranded lingual retainers. It offers numerous perceived advantages to the traditional multi-stranded stainless ste...

T simple stabilizing jigs for bonded lingual retainer wires are easily fabricated from materials in the office, using the following procedure: 1. Bend a circular retentive tag into one end of an .031" stainless steel wire segment.* 2. Double-wind the wire 6-8mm from the tag to form a helix with an internal diameter of 3mm (A). 3. Bend the other end of the wire 90°, leaving a space of about 2mm ...

Discharge valve is very critical component in rotary compressor, and it is a reed valve which consists of valve seat, valve slice and retainer. The motion characteristics of valve slice greatly influence the flowing loss and life of valve. The paper presents a mathematical model to simulate thermodynamic process and motion of the valve simultaneously. Based on the thin-plate theory, the finite ...

This study was made to clarify the retentive force of a denture retainer, i.e., a cone-type stud and sleeve attachment. In order to measure the wearing effect, an engaging and disengaging cycle test of 1,000 times was performed. The effects of taper angle (cone angle), sleeve height and thrusting force at engaging stud and sleeve on retentive force were also analyzed. 1. The cycle test had litt...

INTRODUCTION Hawley retainers (HRs) and vacuum-formed retainers (VFRs) are the 2 most commonly used retainers in orthodontics. However, the basis for selection of an appropriate retainer is still a matter of debate among orthodontists. In this systematic review, we evaluated the differences between VFRs and HRs. METHODS Electronic databases (PubMed, EMBASE, Cochrane Library, ISI Web of Scienc...

The present study was performed to test the tendency for plaque and calculus build-up along the wire of different types of bonded orthodontic canine-to-canine retainers, whether the presence of such retainers causes any damage to the teeth involved, the failure rate of the retainers, and any changes in incisor alignment during a 3-year period of retention. The four test groups received either r...