Abstract
Introduction: Studies of endodontic radiographic working length (WL) determination have mostly involved mature teeth with fully developed root apices. Currently, there are no studies addressing the ability to judge/determine WL, and quality of root fill and coronal restoration in immature teeth.
Objectives:
To investigate the influence of assessor experience/clinical training in radiographic interpretation of WL, quality of root filling and quality of coronal restorations in immature permanent teeth. The influence of apical radiolucency and file size on judgement were also investigated.
Methods:
Human Ethical Approval and was obtained to allow access to patient records and radiographs and Maori consultation entered.
In Part A, 30 periapical radiographs with different levels of files in the root canals were selected. Radiographs were scanned using a film scanner, arranged in a PowerPoint presentation and saved in USB flash drives before distribution to the following group of assessors:
1) ENDO – Endodontists (n=4) with 1 to 24 years of specialist experience and endodontic postgraduate students (n=2)
2) PAEDO – Paediatric dentists (n=4) with 1 to 30 years of specialist experience and paediatric dentistry postgraduate students (n=2)
3) GDP – General dental practitioners (n=7) with a minimum of 10 years working experience
Assessors were asked to mark a scale ranging from -3.0 mm to +3.0 mm in 0.5 mm increments to indicate the length adjustment needed to position the file at the correct WL. In addition, the assessors were also asked to estimate the file size as either small, medium or large.
In Part B, 30 periapical radiographs of root-filled single-rooted immature teeth were selected. Radiographs were scanned, prepared in a PowerPoint and distributed to the same assessors as Part A. Assessors were asked to report on:
a) Length of root filling: As ‘long’, ‘acceptable’ or ‘short’.
b) Quality of root filling condensation: As ‘acceptable’ or ‘poor’.
c) Quality of coronal restoration: As ‘acceptable’ or ‘poor’.
Intra-examiner agreement was assessed for both parts with blinded reviewing of a sample of radiographs already seen.
Two Endodontists who had specialist experience of 13 and 24 years served as the “gold standard” (GS) for both series of images. They viewed the images and reached a consensus.
Descriptive and quantitative data were assessed using SPSS statistical software. One-way analysis of variance (one-way ANOVA) and cross-tabulation were utilized for analysis. Statistical significance was set at P ≤ 0.05. Kappa statistics were used to determine and interpret agreement.
Results:
The absolute agreement of all parameters being assessed between groups and the GS was 64% for ENDO, 57% for the PAEDO and 64% for the GDP. The agreement was low for the assessment on WL adjustment but higher for the other parameters.
For the intra-examiner consistency, the Kappa scores indicate fair agreement (< 0.20 < 0.40) for the determination of the WL adjustment and within moderate to good (< 0.40 < 0.80) for the other parameters.
Conclusion:
The clinical background of the assessor does not appear to influence the radiographic interpretation of images of immature single-rooted teeth. Assessors from all groups had differing opinions of where the optimal position for WL should be; however, there was less variation between the groups in assessing quality of root filling and coronal restoration. The agreement on WL adjustment was low when compared to the other parameters being assessed. Furthermore, the presence of apical radiolucency and the file size did not have a great influence on interpretation. Guidelines for the WL of immature permanent teeth would be valuable.