A retrospective cohort study with follow-up assessment of partial pulpotomy outcomes in the management of irreversible pulpitis in permanent molars with and without molar–incisor hypomineralization

Partial pulpotomy (PP) has demonstrated favorable clinical and radiographic outcomes in permanent molars presenting with symptoms indicative of irreversible pulpitis (IP). However, uncertainties remain regarding the factors associated with treatment outcomes and whether comparable outcomes can be achieved in teeth affected by molar-incisor hypomineralization (MIH), a condition associated with distinctive pulpal characteristics. The aim of this study was to evaluate the clinical and radiographic outcomes of PP in permanent molars presenting with symptoms of IP, to compare treatment outcomes between MIH-affected and non-MIH teeth, and to investigate potential factors associated with treatment outcomes. This retrospective cohort study with a standardized follow-up assessment included children aged 6–15 years who underwent PP in permanent molars diagnosed with IP at a tertiary academic center. Eligible patients attended a follow-up visit for standardized clinical and radiographic evaluation after a minimum follow-up period of 18 months. Clinical and radiographic outcomes were compared between MIH-affected and non-MIH teeth in terms of treatment success and tooth survival. Potential factors associated with treatment outcomes were evaluated using Firth’s penalized logistic regression analysis, including MIH status, sex, age at treatment, tooth location, root maturity, final restoration type, and restoration quality. Eighty-seven teeth (48 MIH-affected and 39 non-MIH) were included. The overall success rate was 88.5%, with success rates of 85.4% and 92.3% in the MIH-affected and non-MIH groups, respectively. No significant differences were observed between the MIH-affected and non-MIH teeth regarding treatment success ( p = 0.501) and survival ( p = 0.726). Among the potential factors evaluated, only restoration quality was significantly associated with treatment outcome. Teeth with unacceptable restorations showed significantly greater odds of PP failure than teeth with acceptable restorations ( p = 0.002). Within the limitations of the study, these findings suggest that MIH status alone may not preclude consideration of PP and may help inform the evidence-based management of MIH-affected permanent molars. They also indicate that restoration quality following PP may be a factor to consider in relation to treatment success.