Effect of modified and conventional facemask therapy on condylar position in Class III patients.

摘要

OBJECTIVES: To assess the effects of varying force direction of maxillary orthopedic protraction on mandibular condylar position. MATERIAL AND METHODS: The conventional facemask group (Group 1) comprised 22 patients, 11 girls, and 11 boys (mean age: 9.3 +/- 1.3 years); the modified facemask group (Group 2) comprised 22 patients, 12 girls, and 10 boys (mean age: 9.4 +/- 1.5 years); and the control group (Group 3) comprised 21 subjects, 11 girls, and 10 boys (mean age: 9.8 +/- 1.9 years). Changes in mandibular position indicator (MPI (R)) measurements of the SAM (R) 3 articulator were evaluated. Treatment and control changes within groups and between groups were analyzed statistically. Intra-group comparisons were tested with the non-parametric Wilcoxon's test and inter-group changes with Kruskal-Wallis. The statistical significance of inter-group differences was further assessed with the Mann-Whitney test for independent samples with Bonferroni's correction. RESULTS: Antero-posterior positional changes of the left condyle were found higher in the controls than in Group 1 (p<0.016). Superior-inferior positional changes of the left condyle were also found significantly higher in controls than in Group 2 (p<0.016). No other significant changes in condylar position were determined in either group. In the treatment groups, asymmetrical condylar position diminished and became symmetrical with treatment in the antero-posterior direction (Group 1: 13.64%, Group 2: 36.37%) plane. In controls, the antero-posterior change of asymmetry was smaller (antero-posterior change: 7.60%). CONCLUSION: These findings generally suggest that modified and conventional facemask therapy with expansion had no adverse effects on the temporomandibular and masticatory system.