Engineering:Quad helix
| Quad helix | |
|---|---|
| Other names | Quadhelix |
| Specialty | Orthodontics |
| MeSH | D009968 |
A quad helix (or quadhelix) is an orthodontic appliance for the upper teeth that is cemented in the mouth.[1] It is attached to the molars by 2 bands and has two or four active helix springs that widen the arch of the mouth to make room for crowded teeth, or correct a posterior cross-bite, where lower teeth are buccal (outer) than upper teeth.[2] It is usually made from 38 mil stainless steel wire and is primarily indicated in mixed dentition, cleft patients and those that have performed the act of thumbsucking. A variety of this appliance is inserted into attachments that are welded to the bands. In this way the orthodontist can adjust the appliance without removing the bands.[3]
The precursor to the quad-helix was the coffin spring. Similar devices known as tri-helices and bi-helices were later developed, with three and two helix springs, respectively.[4]
The expander works by gently pushing the teeth outwards to eventually widen the upper arch. A quad helix expander is usually given to those who have a narrow top jaw, a cross bite and/or crowded teeth.
References
- ↑ Bench, R. W. (1998-12-04). "The quad helix appliance". Seminars in Orthodontics 4 (4): 231–237. doi:10.1016/s1073-8746(98)80028-5. ISSN 1073-8746. PMID 10219178. https://pubmed.ncbi.nlm.nih.gov/10219178.
- ↑ Mitchell, Laura (2007). An Introduction to Orthodontics. Oxford University Press. ISBN 9780198568124.
- ↑ Bench, Ruel W. (1998-12-01). "The quad helix appliance" (in English). Seminars in Orthodontics 4 (4): 231–237. doi:10.1016/S1073-8746(98)80028-5. ISSN 1073-8746. PMID 10219178. https://www.semortho.com/article/S1073-8746(98)80028-5/abstract.
- ↑ Singh, Gurkeerat (December 31, 2007). Textbook of Orthodontics (2nd ed.). New Delhi: Jaypee Brothers Publishers.
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