Prevalence of Hypomineralised Second Primary Molar and its Possible Association with Molar Incisor Hypomineralisation in Children Aged 6-9 Years of Mehsana District, Gujarat, India: A Cross-sectional Study

Introduction: Dental enamel in primary teeth may exhibit a developmental defect known as Hypomineralised Second Primary Molars (HSPM), which presents with clinical signs and symptoms similar to Molar Incisor Hypomineralisation (MIH). Second Primary Molars (SPMs) may serve as a reliable indicator for predicting future hypomineralisation of permanent incisors and molars prior to their eruption. Early identification of HSPM can aid in anticipating future dental challenges such as tooth sensitivity, increased susceptibility to caries and restorative complications in the permanent dentition. Currently, there is limited literature regarding the prevalence of HSPM in Gujarat, India. Aim: To determine the prevalence of HSPM and its possible association with MIH among children 6-9 years in the Mehsana District of Gujarat, India. Materials and Methods: A cross-sectional study was conducted among children aged 6-9 years in the Department of Paediatric and Preventive Dentistry, Narsinbhai Patel Dental College and Hospital, Sankalchand Patel University, Visnagar, Gujarat, India. The district was divided into three zones and a total sample size of 840 children was calculated. Each zone included 280 children selected from both private and government schools. The European Academy of Paediatric Dentistry (EAPD) guidelines were followed for the assessment of both MIH and HSPM, wherein only First Permanent Molars (FPMs) and SPMs were assessed. The collected data were tabulated and analysed using the Chi-square test and the Odds Ratio (OR) was calculated to assess the association between MIH and HSPM. A p-value of