Table 1.
Assessment criteria of anatomical and treatment-related parameters adapted from Venskutonis et al. [17]
| Parameters | Severity criteria |
|---|---|
| Anatomical | |
| Size of periapical radiolucencya (S) |
S0: radiolucency does not exceed 2 times the width of the lateral periodontal ligament space; S1: diameter of well-defined radiolucency up to 3 mm; S2: diameter of well-defined radiolucency 3 : 5 mm; S3: diameter of well-defined radiolucency > 5 mm |
| Relationship between dental root and periapical radiolucency (R) |
R1: radiolucency appears on one root; R2: radiolucency appears on more than one root; R3: radiolucency involves furcation area |
| Location of radiographically detected bone destruction (D) |
D1: radiolucency around root apex; D2: radiolucency is in contact with important anatomical structures; D3: destruction of cortical bone |
| Treatment-related | |
| Canal obturation length (L) |
L0: no obturation material radiographically visible in pulp chamber and in root canal space; L1: obturation material visible in root canal space, 0 : 2 mm from radiographic root apex; L2: obturation material visible in root canal space, > 2 mm from radiographic root apex; L3: extrusion of obturation material through root apex; L4: obturation material radiographically visible only in pulp chamber |
| Obturation homogeneity (H) |
H0: no obturation material radiographically visible in root canal; H1: homogenous appearance of obturation material in root canal space; H2: voids and porosity of obturation material in root canal space |
| Coronal seal (CS) |
CS0: no coronal restoration; CS1: adequate/coronal restoration appears intact radiographically; CS2: inadequate (detectable radiographic signs of overhangs, open margins, recurrent caries, or lost coronal restoration) |
|
Presence of complications/failures (root perforation, untreated/missed root canal, root resorption, root/tooth fracture, endodontically treated root with radiolucency, instrument fracture in root canal) (CF) |
CF0: no; CF1: yes |
| Post inside root canal (P) |
P0: no; P1: yes |
Assessment criteria of anatomical and treatment-related parameters adapted from Venskutonis et al. [17]
aPeriapical lesion on the digital periapical radiography was defined as a radiolucency located in the periapical area of the tooth in connection with the apical part of the root exceeding at least twice the width of the periodontal ligament space [5].
For the cone-beam computed tomography images, the same criterion was applied, and the radiolucency had to be visible at least in two image planes.