Quality of root canal fillings and prevalence of apical radiolucencies in a German population: a CBCT analysis.

Objectives: The aim of this study was to determine the frequency and quality of root canal fillings (RCF) and the prevalence of apical radiolucency (AR) in a German population.

Material And Methods: Five hundred randomly selected full-size CBCT images (Planmeca ProMax 3D, FOV = 8 × 8 cm, voxel size 160 μm or 200 μm) were obtained from German patients (40.6% = ♂; 59.4% = ♀; mean age = 50.21 ± 12.45 years). A total of 8254 teeth were examined for pathology (AR, widened periodontal ligament). The relationship between AR and existing RCF and the quality of RCF were documented. Frequency and correlations between the left and right sides and gender distribution were analyzed statistically using the chi-square test.

Results: The overall prevalence of AR was 3.8%, whereas for teeth with RCF, it was 42.5%. Patients had approximately 1.4 root canal-filled teeth (8.2% of all teeth). RCF terminated more than 2 mm short of the radiological apex in 31.2%, 5.1% reached beyond the apex, 8.1% were associated with extruded sealer, and 5.3% presented untreated root canals. Odds ratio of having an AR was highest in teeth with RCF beyond the apex (OR = 27.0) followed by RCF <2 mm short of the apex (OR = 4.4), untreated root canals (OR = 2.9), and inhomogeneity of RCF (OR = 1.2). Extrusion of sealer was least associated with AR. Molars were most frequently associated with AR (P < 0.05). Root canal-filled teeth showed significantly more AR in men compared with women (P < 0.05).

Conclusions: About 42.5% of root canal-filled teeth were associated with AR, and in about one-third of these teeth, the RCF terminated more than 2 mm short of the apex.

Clinical Relevance: Each step in root canal therapy influences treatment outcome and prevalence of periapical radiolucencies. Determination of the working length is still one of the key points to achieve predictable periapical healing, and homogenous root canal filling reaching the foramen major seems to be essential.