Timing of extraction of compromised first permanent molars and spontaneous space closure without adjunctive orthodontic treatment: a systematic review and meta-analysis.

purposeDemirjian stage E of the second permanent molar (SPM) is widely regarded as the optimal timing for extracting a compromised first permanent molar (FPM) to maximize spontaneous space closure. In pediatric practice, however, delaying extraction until this narrow developmental window is often impractical. This review assessed whether earlier extraction reduces the likelihood of spontaneous space closure without adjunctive orthodontic treatment and identified predictors of successful closure.

methodsSix databases were searched for studies published from 1990 to March 2026, with additional screening of reference lists and grey literature. Eligible studies included patients aged 6-18 years undergoing extraction of compromised FPMs, with assessment of spontaneous space closure without adjunctive orthodontic treatment. Two investigators independently screened studies and extracted data. Risk of bias was assessed using ROBINS-I. Odds ratios (ORs) were pooled for prespecified comparisons. The review was registered in PROSPERO (CRD42024500895).

resultsNineteen studies involving 950 patients and 2,101 extracted FPMs were included. Spontaneous space closure was more frequent in the maxilla than in the mandible (86.3% vs 51.6%), with greater odds of success after maxillary extraction (OR 5.23; 95% CI 3.24-8.45; I

conclusionsFavorable timing for FPM extraction may extend beyond stage E alone. Earlier extraction, particularly before age 10 and within stages D-F, appears compatible with spontaneous space closure.