Impact of Dental Malocclusions on Age and Gender-Related Masticatory Performance in Orthodontic Patients

Orthodontic treatment is often sought for aesthetic and psychosocial reasons, while the functional consequences of dental malocclusions remain less frequently integrated into clinical decision-making.

To evaluate how the presence, type, and combinations of dental malocclusions affect masticatory performance using Indicator of Anatomical Malocclusion (IAM) with objective physiological measures of mastication.

Masticatory performance was assessed using a two-colour chewing gum mixing test (20 chewing cycles; Hue-Check Gum), with colour homogeneity quantified as percentage mixing index (Mix%). Deficient performance was defined as Mix% < 85.44%. Malocclusion was characterized using Angle's classification, number of functional dental units, and IAM assessing craniofacial anomalies, dental number anomalies, crowding, anteroposterior, transverse, and vertical discrepancies. Associations between malocclusion and masticatory performance were explored using univariate followed by logistic regression analyses.

The study included 345 patients (age 14.6 ± 6.9 years) seeking orthodontic consultation. 57.1% of participants exhibited deficient masticatory performance. Independent predictors of deficient mastication included IAM items related to dental number anomalies (OR = 2.59; 95% CI: 1.16-5.75), transverse discrepancies (OR = 1.91; 95% CI: 1.03-3.53), age (OR = 0.92; 95% CI: 0.88-0.96), and Angle Class II/III (OR = 1.65; 95% CI: 1.02-2.66). Subgroup analyses showed that transverse discrepancies increased deficiency in Class I malocclusion, while Class III participants exhibited high prevalence regardless of anomalies. The combination of transverse discrepancy and infraocclusion was associated with the highest prevalence of deficiency (75%).

Using objective masticatory assessment, masticatory performance is associated with dental malocclusions characteristics, and the coexistence of specific traits as captured by the IAM. These findings support the integration of functional evaluation into orthodontic diagnosis. Interventional studies are needed to determine whether orthodontic treatment improves masticatory performance.