• Chawasri Poonvitikul
• Sirima Petdachai

Protraction facemask has been used in the treatment of growing patients with Class III malocclusion derived from maxillary deficiency. Both maxillary complex and upper anterior teeth can be displaced anteriorly by this protraction. Maxillary expansion is advocated to compensate the constriction at the anterior portion of the maxillary during traction even without pretreatment narrow maxilla. A forward and downward protraction force from the anterior portion of maxilla can minimize the counterclockwise rotation of the midface. The facemask therapy may be the most effective for orthopedic change in patients before the peak of puberty. Orthopedic effects require greater forces than do orthodontic movements ;300-500 g of force per side and wearing the facemask for 10-12 hr per day are recommended. The length of treatment time depends on the severity and the age of patients. In addition, it has been shown that the less force and wearing time, the more length of treatment time. After maxillary expansion and protraction are completed, an overcorrection of the overjet and molar relationship is recommended. It is also advisable to use retention devise at night until growth ceases.

(CU Dent J. 2006;29:44-51)