Methods: The sample (26-patients) divided into two groups. The first group (FM+RME) consisted of 13 patients (mean age of 11.6 years, 9-female and 4-male) were treated by a Delaire type face mask with bonded acrylic-splint rapid maxillary expander and the second group (FM) consisted of 13 patients (mean age of 10.4 years, 9-female and 4-male) were treated by Delaire type face mask with a bonded acrylic-splint. A protraction force of 400 to 600 gf was applied to both groups. Once adequate overjet (min 2mm) was obtained in both application groups, face mask therapy was ended. Cephalograms were available at 2 time periods: pretreatment (T1), end of active treatment (T2). The mean T1-T2 interval was 6.8 months for FM+RME and 5.9 months for FM. The soft tissue changes were evaluated on cephalograms. Data were analyzed statistically with paired-t test and ANOVA.
Results: A significant increase in H angle, facial contour angle, lower face height(Sn-Me'), anterior displacement of upper lip, posterior displacement soft tissue pogonion and decrease in lower vermillion height(Sti-Li) were seen in both groups. In the comparison of two groups, soft tissue pogonion, pogonion and lower lip displaced more posteriorly (p<0.01) and upper lip height increased much more and upper incisor view decreased much more in FM+RME group (p<0.05). Nasolabial angle increased in FM+RME whereas it decreased in FM group.
Conclusion: In Class III patients, both appliances are effective in correction of profile. In severe Class III patients, who grows horizontally, soft tissue profile can be improved with using rapid maxillary expansion and face mask together.
*This project is supported by Selcuk-University-Scientific-Research-Project.