Treatment and posttreatment effects of quad-helix/crib therapy of dentoskeletal open bite.

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.

• 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)

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