Association between C-reactive protein, neutrophil to lymphocyte ratio and the burden of apical periodontitis: a case-control study.

OBJECTIVE: Endodontic originated chronic apical periodontitis (AP) is an inflammatory disease of periapical tissue. High-sensitivity C-reactive protein (hsCRP) as an inflammatory marker and hemogram indexes provide valuable information to clinicians for diagnosis, screening and follow-up of various diseases. The aim of this study was to investigate AP in terms of its association with hemogram indices and hsCRP levels.

MATERIAL AND METHODS: Study includes 104 patients with AP and 40 participants as the control group. 160 teeth were diagnosed as AP through digital radiographic images and scored with respect to Periapical Index (PAI) scoring. Afterwards, patients were categorized into 3 grades in accordance with both the number and the severity of AP. AP grade 0 was considered for the control group with regard to a new scoring system. Patients with only one tooth involved with AP with a PAI score of 3 or 4 were categorized as an AP Grade 1, when a patient had more than one tooth with a PAI score of 3 or 4 he was classified as an AP Grade 2 and a patient with at least one tooth scored as a PAI 5 was rated as an AP Grade 3. Hemograms and hsCRP levels were measured for each individual to establish a correlation with inflammatory markers.

RESULTS: The neutrophil/lymphocyte ratio (NLR) levels of patients with AP Grade 3 were significantly higher than all other AP grades (p < .05). hsCRP levels in patients with an AP Grade 2 and 3 were higher than both AP Grade 0 and 1 (p < .05).

CONCLUSIONS: hsCRP levels of patients were reliable predictive indicators for AP severity in correlation with the new proposed scoring system for AP.