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Association Between Hypomineralisation of Second Primary Molars and Tooth Agenesis
Débora Juliana de Araújo Lopes1, Eloisa Cesario Fernandes2, Jaderson Felipe Santos Dantas2
1Dental School, State University of Rio Grande do Norte - UERN, Caicó, Rio Grande do Norte, Brazil.
Background:
Hypomineralisation of second primary molars (HSPM) is an enamel defect with a multifactorial and potentially genetic aetiology. While the association between enamel defects and dental anomalies is a relatively recent area of investigation, it has not yet been explored specifically in cases of HSPM.
Aim:
To assess the association between HSPM and tooth agenesis (TA).
Design:
A retrospective cross-sectional study was performed using pre-treatment records of patients aged 7-12 years. A total of 285 patient records were evaluated. Statistical analyses were performed using the Fisher's exact test and logistic regressions.
Results:
A higher prevalence of TA was observed among children with HSPM-affected teeth (95% CI: 1.07-3.17, φ-coefficient: 0.238, PR: 1.84). Individuals with severe HSPM had significantly greater odds of TA (OR = 12.47; p < 0.001; 95% CI: 3.47-24.70). Patients with HSPM had a significantly higher likelihood of experiencing TA (OR = 6.97), particularly second premolar agenesis (OR = 11.80; p < 0.001; 95% CI: 2.83-49.10).
Conclusion:
An association was found between HSPM and TA, particularly involving mandibular second premolars. Moreover, increased HSPM severity was linked to a higher risk of developing TA.
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