Late Maxillary Protraction in Patients with Unilateral Cleft Lip and Palate: A Retrospective Study

• Published in: The Cleft palate-craniofacial journal Vol. 51; no. 1; pp. 1 - 10
• Main Authors: Borzabadi-Farahani, Ali, Lane, Christianne J., Yen, Stephen L.-K.
• Format: Journal Article
• Language: English
• Published: Los Angeles, CA SAGE Publications 01-01-2014; SAGE PUBLICATIONS, INC
• Subjects: Adolescent; Birth defects; Case-Control Studies; Cephalometry; Cleft Lip - rehabilitation; Cleft Palate - rehabilitation; Dentistry; Extraoral Traction Appliances; Female; Humans; Male; Maxilla - abnormalities; Maxillofacial Development; Medical treatment; Mouth; Orthodontic Appliances; Orthodontics; Orthodontics, Interceptive; Palatal Expansion Technique; Retrospective Studies; Studies; Treatment Outcome; late maxillary protraction; face mask; suturai loosening; alternate rapid maxillary expansion and constriction; cleft lip and palate
• ISSN: 1055-6656; 1545-1569
• DOI: 10.1597/12-099

Objectives
This retrospective study assessed the dentoskeletal effect of late maxillary protraction (LMP; reverse-pull headgear, Class III elastics, and maxillary suturai loosening) in unilateral cleft lip and palate (UCLP) patients versus a control group of untreated UCLP patients.
Materials and Methods
Cephalograms taken at age 13 to 14 years (T1) and 17 to 18 years (T2) were used for this study. The study group comprised 18 patients (10 male and 8 female, mean age at start of LMP therapy = 13.4 [0.45] years). A control groups of 17 patients (8 male and 9 female, mean age = 13.5 [0.44] years) was used for comparison.
Results
The repeated-measures analysis of variance showed statistically significant changes across time between groups for the following variables (mean difference [T2–T1] in the study group, 95% confidence interval): SNA (°) (1.95, 0.75 to 3.15), A ┴ Na Perp (mm) (1.82, 0.86 to 2.77), CoA (mm) (2.92, 1.53 to 4.31), ANB (°) (3.13, 2.02 to 4.24), Wits (mm) (7.82, 5.01 to 10.54), Mx-Md Diff (mm) (0.62, −1.58 to 2.83), Occl P-SN (°) (-3.98, −5.99 to −1.98), overjet (mm) (8.82, 5.90 to 11.74), FMIA (°) (4.05, −0.05 to 8.15), and IMPA (°) (-5.77, −9.74 to −1.80). Late maxillary protraction created a slight open bite (0.66 mm). Trends for overeruption of mandibular incisors and an increase in lower face height (P = .07 for both) were noted in the study group.
Conclusions
Late maxillary protraction produced a combination of skeletal changes (protraction of maxilla, improvement in the maxillo-mandibular skeletal relationship) and dental compensations (counterclockwise rotation of occlusal plane, retroclination of mandibular incisors) in patients with UCLP. Late maxillary protraction was also associated with some unwanted tooth movements (open bite tendency, mandibular incisors overeruption).