Assessment of the Occlusal Support Area in Children with Mixed Dentition: A Clinical Cross-Sectional Study from Oradea, Romania

Background/Objectives: The integrity of the primary teeth in the occlusal support area is essential for the eruption of the permanent successor teeth and for the development of a functional occlusion. This study aimed to clinically evaluate the health status of the primary teeth in the occlusal support area among children in the early mixed dentition attending an orthodontic practice in Oradea, Bihor County, Romania, and to analyze the pattern and prevalence of damage to this area by age and sex. Methods: This observational, cross-sectional, descriptive-analytical study was conducted at a specialized orthodontic practice in Oradea, Romania, between January and June 2026. A total of 255 patients aged 6–9 years (136 girls, 119 boys) were included, selected through consecutive sampling from an initial group of 308 patients. The evaluated variables included the integrity of the occlusal support area, the presence of caries, premature extractions, their combination, location, and the type of extracted primary molars. Comparisons between age and sex groups were performed using Fisher’s Exact Test, with Bonferroni-corrected Z-tests. Results: The occlusal support area was damaged in 72.2% of patients, most frequently through a combination of premature extractions and caries (52.7%). Damage increased significantly with age, from 54.8% at 6 years to 80% at 8 years (p = 0.032). The second primary molar was the most frequently extracted tooth (62%). No significant sex-based differences were observed across the overall sample, except for a significant association at 7 years of age (p = 0.001), where girls more frequently presented isolated premature extractions. Conclusions: The occlusal support area is frequently affected in children with early mixed dentition who attended the orthodontic practice from Oradea, Romania, with damage increasing progressively between 6 and 8 years of age. These findings support the need for active monitoring and early preventive interventions during this critical developmental period.