Hypersensitivity in teeth affected by molar-incisor hypomineralization (MIH)

Tooth hypersensitivity is a common symptom in patients with molar-incisor hypomineralization (MIH). Therefore, this clinical study aimed to assess potential associations between patient- and tooth-related variables and the intensity of hypersensitivity in MIH-affected permanent teeth compared to healthy controls. Fifty-seven MIH patients and 20 healthy adolescents with a total of 350 MIH-affected and 193 healthy teeth were included in this study. The intensity of hypersensitivity was measured after cold air stimulation using the Schiff Cold Air Sensitivity Scale (SCASS) by the dentist and visual analogue scale (VAS) by the patient. Tooth hypersensitivity was low in non-MIH teeth (97.9% of the group had zero SCASS and VAS values). In contrast, MIH-affected teeth with demarcated opacities and atypical restorations had moderate SCASS and VAS values, whereas teeth with enamel breakdown were mostly linked to severe hypersensitivity. The logistic regression model confirmed a significantly lower level of hypersensitivity in MIH patients aged ≥ 8 years (OR 0.06, 95% CI 0.01-0.50, p = 0.009) and higher levels in molar teeth (OR 5.49, 95% CI 1.42-21.27, p = 0.014) and teeth with enamel disintegration (OR 4.61, 95% CI 1.68-12.63, p = 0.003). These results indicate that MIH-related tooth hypersensitivity seems to be present in disintegrated molars immediately after tooth eruption.