Diagnosis of approximal carious lesions with Digital and Analogue imaging systems

Introduction: Studies about intra-oral radiographies tend to use bitewing for approximal caries detection rather than for occlusal lesions. Objectives: To compare the approximal caries diagnosis by different examiners, in posterior teeth, using bitewings, digital (photostimulable phosphor/PSP) and analogue (film) imaging systems. Materials and Methods: Observational cross-sectional trial, approved by Ethics Committee; 45 adult patients, who voluntarily attended FHS-UFP operative dentistry appointment. Data from patient's files were collect. Visual observation of bitewings, made during appointments, with PSP (13 patients) and film (32 patients), was performed by 5 examiners (categorized in 3 groups according time of clinical practice (CP): One dentist (D)≥15years; 3D with 10-15years; One D5years), to detect approximal caries in 1800 surfaces. ICDAS criteria were applied for caries registration. "Dentist≥15 years" was defined as reference/control for calibration. The inter-examiner diagnosis comparison was done with intraclass correlation coefficient/ICC; Statistical analysis performed with α=0.05. Results: 1025 surfaces registered; Sound surfaces: 859(47.72%); Approximal caries detection: 166(5.22%); 5.22% (dentine)/4.00% (enamel). Very high to high agreement values (ICC: 0.866-0.978) were obtained; Examiners with less CP showed agreement levels significantly smaller for both imaging systems. More trials are needed to evaluate and compare the diagnosis performance and calibration of examiners, when using different x-ray detectors. Conclusions: Diagnosis of approximal caries, using X-ray detectors, show an inter-examiner agreement high but differences were detected for the examiners according to image systems (PSP/film) used. Clinical implications: Approximal caries detection can be better detected using bitewing, with imaging systems that should produce maximum diagnostic information minimizing patient x-ray dose. Keywords: Intra-oral radiography; digital radiography; film; analogue radiography, carious lesions detection, diagnosis, photostimulable phosphor (PSP), bitewing radiography