Comparison of the Planas Functional Masticatory Angle Across Deciduous, Mixed, and Permanent Dentition Stages: A Cross-Sectional Pilot Study

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.