Abstract | OBJECTIVE: To investigate the effects of the quad-helix/ crib (Q-H/C) appliance in subjects with thumb-sucking habits and dentoskeletal open bite at 2 years after the end of active treatment. MATERIALS AND METHODS: The records of 21 subjects treated with the Q-H/C appliance were compared with a control group of 21 untreated subjects with similar vertical relationships. Lateral cephalograms were obtained before treatment (T1; mean age 8.4 +/- 1.4 years) and at about 2 years after treatment (T2; mean age 11.7 +/- 1.9 years) and analyzed. Mean treatment duration was 1.5 years +/- 7 months. The T2-T1 changes in the two groups were compared with a nonparametric test for independent samples. RESULTS: The mean increase in overbite during Q-H/C therapy (4.1 mm) represented an overcorrection of the amount of anterior open bite at T2. Both the maxillary and mandibular incisors showed significantly greater extrusion in the Q-H/C group than in the control group. The treated group showed a greater downward rotation (1.8 degrees ) of the palatal plane than did the control group. This change was associated with a clinically significant reduction in the palatal plane/mandibular plane angle (-2.5 degrees ) in the Q-H/C group. The upper lip showed significant retraction relative to the E-plane in the treated group (3.6 mm) compared with the controls. CONCLUSIONS: The Q-H/C appliance was effective in correcting dental open bite in 85% of the growing subjects with thumb-sucking habits and dentoskeletal open bites. Correction of anterior open bite was associated with a clinically significant improvement in maxillomandibular vertical skeletal relationships.
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Authors | Paola Cozza, Manuela Mucedero, Tiziano Baccetti, Lorenzo Franchi |
Journal | The Angle orthodontist
(Angle Orthod)
Vol. 77
Issue 4
Pg. 640-5
(Jul 2007)
ISSN: 0003-3219 [Print] United States |
PMID | 17605486
(Publication Type: Journal Article)
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Topics |
- Case-Control Studies
- Cephalometry
(statistics & numerical data)
- Child
- Female
- Fingersucking
(adverse effects)
- Humans
- Male
- Open Bite
(etiology, therapy)
- Orthodontic Appliances
- Palatal Expansion Technique
(instrumentation)
- Statistics, Nonparametric
- Treatment Outcome
- Vertical Dimension
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