Skip to main content
NCBI home page
Korean Journal of Orthodontics logoLink to Korean Journal of Orthodontics
letter
. 2013 Feb 26;43(1):1–2. doi: 10.4041/kjod.2013.43.1.1

Reader's Forum

Marlos Eurípedes de Andrade Loiola 1
PMCID: PMC3594874  PMID: 23505618

Ahn HW, Chung KR, Kang SM, Lin L, Nelson G, Kim SH

Correction of dental Class III with posterior open bite by simple biomechanics using an anterior C-tube miniplate.

- Korean J Orthod 2012;42(5):270-278

Q1. I would like to congratulate the authors for publishing the article, which shows a precise, controlled and simple solution for a critical clinical situation. Accor ding to Figure 5, correction of the posterior open bite occurred in just 4 months. The figure also shows the left posterior occlusion reached a more desirable relationship than the rights after 4 months. This posterior occlusal imbalance, perhaps due to unequal bilateral arch force, seems to require some additional correction of right mandibular posterior teeth during the finalization of the orthodontic therapy.

Q2. Another question. As the teeth positions improved, has there been any height changes of brass wire in C-tube miniplate? Also, I can assume that the amount of force delivered can be controlled by the thickness of the wire in the reverse curve. What is the average force level advocated by the authors for this therapy?

Figure 1.

Figure 1

Open in a new tab

Uprighting lower posterior teeth using C-tube and reverse NiTi wire.

Korean J Orthod. 2013 Feb 26;43(1):1–2.
Hyo-Won Ahn 1

A. Thank you very much for your kind words and also for your interest in this article.

A1. Because the C-tube miniplate was inserted between the mandibular central incisors and symmetric preformed reverse NiTi wire was activated at the center of the arch, the force system inherented in this appliance design can be regarded as symmetrical. However, differences in the amount of mesial inclination or the numbers of bonded posterior teeth or the amount of posterior arch length discrepancy can cause asymmetric uprighting between left and right sides. If then, I would recommend customized arch bending or selective posterior bonding such as bonding last molar only on the more tipped side.

In our case, the uprighting of posterior segement was fully achieved both left and right segments. After 4 months, the interdigitation of upper and lower arches was not established yet due to premature lingual occlusal contacts on the right side. Therefore, poterior openbite seemed to remain on the buccal aspects. At debonding, insufficinet buccal overjet of right posterior molars was related to finishing procedure, not to uprighting force system itself.

A2. Because the C-tube miniplate was inserted between the mandibular central incisors and symmetric preformed reverse NiTi wire was activated at the center of the arch, the force system inherented in this appliance design can be regarded as symmetrical. However, differences in the amount of mesial inclination or the numbers of bonded posterior teeth or the amount of posterior arch length discrepancy can cause asymmetric uprighting between left and right sides. If then, I would recommend customized arch bending or selective posterior bonding such as bonding last molar only on the more tipped side.

In our case, the uprighting of posterior segement was fully achieved both left and right segments. After 4 months, the interdigitation of upper and lower arches was not established yet due to premature lingual occlusal contacts on the right side. Therefore, poterior openbite seemed to remain on the buccal aspects. At debonding, insufficinet buccal overjet of right posterior molars was related to finishing procedure, not to uprighting force system itself.

Articles from Korean Journal of Orthodontics are provided here courtesy of Korean Association of Orthodontists

RESOURCES