Prediction of treatment outcome following correction of anterior crossbites in the mixed dentition: orthodontic versus orthopaedic methods.

Abstract

AIM:

To separate subjects with anterior crossbite and mild maxillary deficiency into two groups: those that can be treated successfully with a 2 x 4 appliance and those that should be treated with reverse headgear and maxillary expansion.

METHODS:

Thirty mixed dentition subjects each with an anterior crossbite, a concave profile, a deficient maxilla, and an ANB angle between -2 and +1 degrees were used. Fifteen subjects (8 boys, 7 girls; Mean age: 9.17 +/- 1.1 years) were successfully treated with a 2 x 4 appliance (orthodontic treatment group) and remainder (5 boys, 10 girls; Mean age: 8.6 +/- 1.5 years) were successfully treated with reverse headgear and maxillary expansion after initial treatment with a 2 x 4 appliance had failed (orthopaedic treatment group). Unstandardised discriminant function coefficients and a constant were calculated for selected pretreatment cephalometric variables.

RESULTS:

The NSAr angle was significantly smaller (p < 0.01) and both anterior and posterior cranial base lengths were significantly longer in the orthodontic treatment group (p < 0.001) compared with the orthopaedic group. The prediction index developed was: (PI) = -0.2 NSAr + 0.243 S-N + 0.187 S-Ar + 3.366. The critical score was 0. With positive scores a 2 x 4 appliance can be used and with negative scores reverse headgear and expansion are indicated.

CONCLUSION:

An equation able to predict treatment success with either a 2 x 4 appliance or reverse headgear has been developed.

• Authors: Yan Gu
• Journal: Australian orthodontic journal (Aust Orthod J) Vol. 21 Issue 1 Pg. 25-30 (May 2005) ISSN: 0587-3908 [Print] Australia
• PMID: 16433078 (Publication Type: Comparative Study, Journal Article)

Topics

• Algorithms
• Cephalometry
• Child
• Dentition, Mixed
• Extraoral Traction Appliances
• Female
• Follow-Up Studies
• Forecasting
• Humans
• Incisor (pathology)
• Male
• Malocclusion (pathology, therapy)
• Maxilla (pathology)
• Orthodontic Brackets
• Orthodontic Wires
• Orthodontics, Corrective (methods)
• Palatal Expansion Technique
• Skull Base (pathology)
• Treatment Outcome