AbstractBackgroundThis study was conducted to investigate the biological factors underlying the association between pulp necrosis (PN) in subjects with permanent teeth with intact crowns and sickle cell anemia (SCA).MethodsThis cohort study included 140 subjects: 125 without PN and 15 with PN. A theoretical model was built to explore the following biological factors involved in the association between PN and SCA, namely (a) increased number of sickle cell crises in the previous year (No. SCCs/year), (b) low percentage of blood oxygen saturation (SpO2) in the body, and (c) comorbidities (CoMs). The theoretical model for testing associations was analyzed by structural equation modeling.ResultsPN was associated with CoMs (SFL = 1.115; p = .032) but not with No. SCCs/year (SFL = .127; p = .596) or body SpO2 (SFL = −.102; p = .485). The prevalence rates of osteoarticular lesions (p = .009) and death(p<.001) were significantly higher in subjects with PN than in those without.ConclusionsComorbidities, primarily osteoarticular lesions, are associated with PN in permanent teeth with intact crowns of patients with SCA. PN can be considered an indicator of the lethality of SCA.