Dentoskeletal effects of early class III treatment protocol based on timing of intervention in children.

BACKGROUND: To detect the optimal timing of intervention based on different cervical vertebral maturation stage (CS1-2 vs. CS3-4) for the treatment of Class III malocclusion with early Class III protocol. METHODS: A total sample of 43 patients (23 females, 20 males) ranging between 7 and 13 years of age with dentoskeletal Class III malocclusion treated with the modified SEC III (Splints, Elastic and Chincup) protocol divided into two groups based on the cervical vertebral maturation stages (CS1-2 and CS3-4) was included in this retrospective observational longitudinal study. Patient compliance was assessed using a 2-point Likert scale. Statistical comparisons between the two groups were performed with independent sample t tests. RESULTS: No statistically significant differences for any of the cephalometric variables describing the baseline dentoskeletal features were found between the two groups except for the mandibular unit length that was significantly greater in the pubertal group (P = 0.005). The modified SEC III protocol produced favorable sagittal outcomes in both groups, whereas no statistically significant T1-T2 changes were found between the CS1-2 and CS3-4 groups for any of the angular and linear measurements. No significant differences were found in the prevalence rates of the degree of collaboration between the two groups (P = 1.000). CONCLUSIONS: No significant differences between prepubertal and pubertal patients were found in the sagittal and vertical dentoskeletal changes with the modified SEC III protocol. Thus, this early Class III treatment produced similar favorable effects in growing subjects regardless of the cervical vertebral maturation stages from CS1 to CS4.

Modified SEC III protocol: vertical control related to patients' compliance with the chincup.

OBJECTIVES: To compare the short-term outcomes of modified SEC III protocol in growing patients in relation to their compliance with the chincup, matching them with an untreated Class III control group (CG). MATERIALS AND METHODS: Thirty-four patients (mean age of 8.6 ± 1.2 years) with Class III dentoskeletal malocclusion treated with the modified SEC III protocol and divided into group 1 (G1, 18 subjects), reporting good compliance and group 2 (G2, 16 subjects) not compliant with the chincup. The records were analysed before treatment (T1) and after the orthopaedic phase (T2), with an interval period of about 1.3 ± 0.5 years. The CG consisted of 16 untreated subjects with Class III dentoskeletal malocclusion (mean age of 8.3 ± 1.4 years). The statistical comparisons among the three groups were performed with ANOVA with Tukey's post hoc tests. RESULTS: Both G1 and G2, compared with CG, presented significant improvements in the sagittal skeletal relationships (ANB +2.5° and +2.5°, Wits +4.2° and +3.0°, respectively). G1 exhibited a significant more favourable control of vertical skeletal relationships when compared to G2 (Palatal Pl.-Mandibular Pl. -2.0°) that were associated with a statistically significant reduction of the gonial angle (ArGoMe -1.7°). Limitations of the study were its retrospective nature and the lack of evaluation of the long-term outcomes. CONCLUSIONS: Both groups of treated patients showed favourable sagittal skeletal improvement compared with controls. The use of chincup in patients with good compliance produced significantly greater control of the skeletal vertical dimensions compared with patients not compliant with the chincup.