A Cross‐Sectional Study on Apical Periodontitis in Root‐Filled Teeth: Do Clinically Available Factors Reflect Inflammation Level?

ABSTRACT Aim Perceived severity of the condition is one of several factors influencing clinical decision‐making regarding the management of root‐filled teeth with persistent apical radiolucency. However, whether clinically available factors can indicate the severity of persistent apical lesions remains unclear, particularly in asymptomatic cases. The present study aimed to investigate whether factors relating to demographic characteristics, dental history, and clinical and radiographic status reflect inflammation level in apical periodontitis in root‐filled teeth. The objective was to improve the understanding of inflammation level in apical lesions associated with asymptomatic root‐filled teeth and to support clinical decision‐making. Methodology This cross‐sectional study was performed on adult patients from a dental clinic in Copenhagen, Denmark. Dental history and clinical information were collected in a pre‐designed form, together with radiographic data and biopsies of periapical tissue from root‐filled teeth with apical periodontitis, between April 2021 and September 2023. Inflammation level was graded histologically and compared to groups stratified by demographic characteristics, dental history, clinical findings, age and status of root filling and radiographic factors. Inter‐observer agreement was assessed using kappa statistics. Data was analysed with One‐Way ANOVA, Chi 2 test, or Fisher's exact test, and correction for multiple testing was applied using the Holm–Bonferroni method. p ‐values < 0.05 were considered statistically significant. Results One hundred and nine biopsies from 109 patients were included. A significant difference in inflammation level was found between cases categorised as asymptomatic apical periodontitis and cases categorised as symptomatic apical periodontitis ( p = 0.023). No significant difference in inflammation level was observed when comparing groups stratified by demographic characteristics, dental history, or clinical or radiographic status in cases categorised as asymptomatic or symptomatic apical periodontitis. Conclusions In root‐filled teeth with apical periodontitis, the presence of symptoms and/or clinical manifestation of disease seems to reflect and provide some indication of apical inflammation level. Nonetheless, factors relating to demographic characteristics, dental history and clinical and radiographic status do not seem to reflect the level of apical inflammation. In the clinical decision‐making process, caution is therefore warranted when using these factors to estimate inflammatory burden in apical lesions associated with root‐filled teeth without symptoms or clinical manifestation of disease.