Early treatment of skeletal class III malocclusion with facemask therapy in Vietnam

To evaluate the effects of facemask therapy on skeletal class III malocclusion in the Vietnamese population. This interventional trial enrolled a total of 31 children, dividing them into two age groups: Children aged 7 to 9 (54.8%), who were in the pre-pubescent or early mixed dentition stages, comprised one group. The other group consisted of 14 children, representing 45.2%, who were in the mid-pubescent or late mixed dentition stage, aged 7 to 9. All of them had skeletal class III maxillary deficiency (Angle formed by the A-nasion line and B-nasion line <= 0 degrees, Wits appraisal <= 2). The study aimed to investigate how age affects changes in lateral cephalometric measurements before and after treatment. The research involved clinical records, lateral cephalograms, and dental casts. Both qualitative and quantitative variables were evaluated using specific statistical tests. Fisher's exact test was used for qualitative variables, while paired samples t-tests and independent samples t-tests were used for quantitative variables. In cases where the data did not follow a normal distribution, the Wilcoxon test and Mann-Whitney U-test were used (p <= 0.05). The study found that using a facemask improved the skeletal, dental and soft tissues. It led to a forward movement of the maxilla and a rotation of the mandible, resulting in a better relationship between the maxilla and mandible. The upper incisors shifted from a crossbite to a positive overbite, and the upper lip protruded forward. The concave face became more prominent and aesthetically pleasing. Most individuals (80.6%) had positive outcomes, with the highest proportion among children aged 7-9 years. Based on the study's findings, the facemask was highly effective for both age groups in skeletal class III malocclusion. The group of children aged 7-9 years with maxillary deficiency was more efficacious than the group of children aged 10-12 years.