Galan-Lopez L, et al. Korean J Orthod. 2019 May;49(3):140-149. https://doi.org/10.4041/kjod.2019.49.3.140

The control of vertical dimension remains a critical aspect of comprehensive orthodontic treatment. This study compared vertical dimensional changes produced by clear aligners (CAs) to those produced by fixed appliances (FAs) during comprehensive orthodontic treatment, assessing whether modern aligner therapy provides comparable vertical control with conventional mechanics. A prospective cohort of 52 adults (CA group: 26 and FA group: 26) was evaluated. Baseline comparability was confirmed for age, sex, malocclusion type, and skeletal pattern. Standardized lateral cephalograms were obtained before (T₀) and after treatment (T₁). Cephalometric variables included the SN-GoGn (mandibular plane angle), FMA (Frankfort-mandibular plane angle), N-Me (total anterior facial height), S-Go (posterior facial height), and ANS-Me (lower anterior facial height). Intraobserver and interobserver reliability exceeded an intraclass correlation coefficient of 0.90. Paired and intergroup comparisons were performed (α = 0.05). Both groups exhibited small increases in vertical parameters within physiological limits. In the CA group, the SN-GoGn angle showed a statistically significant but clinically minor increase (<1°; P = 0.016). The FA group presented slightly greater increases in SN-GoGn and plane angle FMA (P 0.05), and effect sizes were small (Cohen d <0.30). Vertical dimensional changes associated with CA and FA treatments were minimal and comparable. Under current protocols, CAs provide adequate vertical control in mild-to-moderate malocclusions without inducing clinically relevant mandibular rotation. Further randomized and 3-dimensional studies are warranted to confirm these findings in more complex vertical discrepancies.

Background. The Planas Functional Masticatory Angle [PFMA] is a functional parameter describing mandibular trajectory during mastication. Its variation across dentition stages may reflect cross-sectional physiological functional adaptation during growth. Methods. A cross-sectional pilot study recruited 30 patients [10 per group: deciduous, mixed, permanent dentition] from a university dental clinic. PFMA was measured using a standardized intraoral photographic protocol, with intra-examiner reliability assessed [ICC > 0.9]. Molar relationships were classified per Angle’s classification. PFMA differences across dentition stages were analyzed using one-way ANOVA, and molar class distributions were evaluated with chi-square tests [p < 0.05]. Results. PFMA values decreased significantly from deciduous [64.7° ± 6.9] to mixed [55.5° ± 7.8] and permanent dentition [47.2° ± 9.8] [ANOVA, p < 0.001]. Post hoc analysis revealed significant differences between deciduous and permanent stages. No significant right–left PFMA differences were observed. Class I molar relationships predominated [70%], and no significant association was found between PFMA and molar class. Conclusions. This pilot study suggests PFMA decreases with dentition progression, reflecting physiological occlusal adaptation. Class I predominance supports functional symmetry, but PFMA-molar class associations require larger samples. Longitudinal studies are needed to further explore the clinical applicability of PFMA as a functional descriptor of masticatory adaptation.

Objectives: To describe foot and global postural deviations in a mixed-age university-clinic sample and examine their associations with cephalometrically defined sagittal skeletal class and facial growth pattern. Methods: This cross-sectional study included 98 individuals aged 8–62 years; 76 participants (77.6%) were adults. Foot posture was assessed with the FPI-6 and plantar footprint, global posture by sagittal-plane visual analysis, and centre-of-pressure behaviour by instrumented gait in a subsample. Associations were tested using chi-square or Fisher–Freeman–Halton exact tests, Cramér’s V, and Bonferroni-adjusted p-values. Age- and sex-adjusted continuous modelling was not possible because complete data could not be reliably reconstructed. Results: Supination was the most frequent FPI-6 category (45.9%), and 30.8% showed ideal alignment. Sagittal skeletal class was not associated with any outcome (all p ≥ 0.341; all pBonf = 1.000). Facial pattern was associated with FPI-6 in the primary analysis (exact p = 0.007; V = 0.265), but not after Bonferroni correction (pBonf = 0.070). The five-category sensitivity analysis remained significant (exact p = 0.0016; pBonf = 0.016; V = 0.353), although intermediate groups were small. Conclusions: No detectable association was found between sagittal skeletal class and foot, postural, or gait variables. The facial-pattern finding remains exploratory, and the lack of age and sex adjustment limits inference.

Biological maturation varies substantially among children of the same chronological age, which may affect growth-based orthodontic decisions. In this cross-sectional study, 120 patients aged 8 to 16 years were evaluated using routine orthodontic diagnostic records. Chronological age was compared with dental age estimated using the Nolla and Demirjian methods, and skeletal maturation was assessed using cervical vertebral maturation stages (CVMS). Associations with sex, BMI, BMI-for-age z-score, and menarcheal status in females were examined. Both dental methods systematically overestimated chronological age. Mean discrepancies were +0.59 years for the Nolla method (95% CI: 0.39-0.79; Cohen's dz = 0.52) and +1.09 years for the Demirjian method (95% CI: 0.87-1.31; Cohen's dz = 0.89) (both P < 0.001). Female participants exhibited a higher proportion of pubertal and postpubertal CVMS than males (Cramer's V = 0.41; P < 0.001), although sex differences in dental age discrepancies were small (Cohen's d ≤ 0.14). BMI and BMI-for-age z-scores were positively correlated with dental age discrepancies (ρ = 0.27-0.31) and CVMS stage (ρ = 0.35-0.36) (all P ≤ 0.003), indicating small-to-moderate associations. Menarcheal status was not significantly associated with CVMS (P = 0.727) or dental age discrepancies (P > 0.05). Chronological age alone provides an incomplete estimate of biological maturation. Dental age estimation and CVM assessment offer complementary but nonequivalent information, and their interpretation should consider sex and basic anthropometric context.