Radiographic indicators of favorable second permanent molar eruption are infrequently present at the time of first permanent molar extraction: a retrospective study

BACKGROUND: First permanent molars (FPMs) erupt early and remain exposed to the oral environment for prolonged periods, making them particularly susceptible to dental caries, molar-incisor hypomineralization (MIH), restorative failure, and repeated restorative intervention. When long-term prognosis becomes unfavorable, extraction may represent a biologically appropriate treatment option. Favorable spontaneous eruptive adaptation of the second permanent molar (SPM) has been associated with several radiographic and developmental variables. This retrospective radiographic study evaluated demographic and panoramic radiographic parameters associated with favorable eruption potential of SPMs in children with indicated FPM extraction and investigated whether established radiographic conditions were present at the time extraction decisions were made. METHODS: Following ethical approval, panoramic radiographs of 500 pediatric patients presenting with extraction-indicated FPMs (n = 712) were retrospectively evaluated. Demographic characteristics, dentition stage, number and location of affected FPMs, and extraction indications were recorded. Radiographic assessment included evaluation of SPM developmental stage according to Demirjian classification, SPM angulation, and presence of a third permanent molar (TPM) germ. Statistical analyses were performed using SPSS version 29.0. Descriptive statistics, chi-square tests, and multivariable logistic regression analyses were applied, with statistical significance established at p < 0.05. RESULTS: The mean age of the study population was 128.39 ± 22.11 months; 54.6% were girls and 45.4% boys. Extensive carious destruction (91.4%), repeated treatment interventions, severe structural breakdown, and MIH-related defects represented the principal indications for extraction. Radiographically, 17.6% of SPMs were classified as Demirjian stage E and 27.4% as stage F. Mesial angulation was observed in 55.2% of cases, while a TPM germ was present in 74.2%. However, only 12.8% of cases (62 patients, 91 teeth) fulfilled all predefined radiographic conditions associated with favorable eruption potential following FPM extraction. CONCLUSION: Radiographic conditions associated with favorable eruption potential of SPMs were present in only a limited proportion of cases at the time FPM extraction decisions were established. These findings highlight the discrepancy between theoretically favorable developmental timing conditions and the clinical realities of pediatric dental practice, where extraction is frequently necessitated by advanced structural disease. Systematic radiographic evaluation of SPM developmental stage, angulation, and TPM germ presence should therefore be incorporated into individualized treatment planning.