A new protocol for maxillary protraction in cleft patients: repetitive weekly protocol of alternate rapid maxillary expansions and constrictions.
OBJECTIVE
It was hypothesized that, through a repetitive weekly protocol of Alternate Rapid Maxillary Expansions and Constrictions (Alt-RAMEC), the maxilla in cleft patients could be protracted more effectively than with a single course of rapid maxillary expansion (RME).


METHODS
Twenty-six consecutive unilateral cleft lip and palate patients at the age of mixed dentition were included in this prospective clinical study. The rapid maxillary expansion group included the first 16 consecutive patients undergoing 1 week of rapid maxillary expansion (1 mm/day) followed by 5 months, 3 weeks of maxillary protraction. The Alternate Rapid Maxillary Expansions and Constrictions group included the next 10 consecutive patients undergoing 9 weeks of Alternate Rapid Maxillary Expansions and Constrictions followed by 3 months, 3 weeks of maxillary protraction. Daily activation of the weekly expansion or constriction was 1.0 mm. Two-hinged expanders and intraoral maxillary protraction springs were used in both groups. Treatment results were evaluated cephalometrically.


RESULTS
The amount of maxillary anterior displacement by the 2-hinged expander in the Alternate Rapid Maxillary Expansions and Constrictions group was 3.0 +/- 0.9 mm at A point, significantly greater than the 1.6 +/- 1.0 mm in the rapid maxillary expansion group. The amount of maxillary advancement with intraoral protraction springs in the Alternate Rapid Maxillary Expansions and Constrictions group was 2.9 +/- 1.9 mm at A point, significantly greater than the 0.9 +/- 1.1 mm in the rapid maxillary expansion group. The overall amount of maxillary advancement in the Alternate Rapid Maxillary Expansions and Constrictions group was 5.8 +/- 2.3 mm at A point. This result remained stable, without significant relapse after 2 years.


CONCLUSIONS
Maxillary protraction using the 2-hinged expander, a repetitive weekly protocol of Alternate Rapid Maxillary Expansions and Constrictions, and intraoral protraction springs is most effective, with stable results at 2-year follow-up.
Liou
Eric Jein-Wein
EJ
Department of Orthodontics and Craniofacial Dentistry, Chang Gung Memorial Hospital, Taipei, Taiwan. lioueric@ms19.hinet.net
Tsai
Wen-Ching
WC
D002508:Cephalometry; D002648:Child; D002972:Cleft Palate / Q000628:therapy*; D002985:Clinical Protocols; D003250:Constriction; D005260:Female; D006801:Humans; D008297:Male; D008437:Maxilla; D009967:Orthodontic Appliances; D010155:Palatal Expansion Technique / Q000295:instrumentation; D011446:Prospective Studies; D063173:Retrognathia / Q000628:therapy*