Figure 1.

Measurement procedure for assessment of root length and marginal bone level by means of reformatted images in axial, sagittal, and coronal planes. (a) Root length—measurement from a reference line between buccal and palatal cemento-enamel junction (CEJ) to apex. The levels of CEJ and root apex were assessed using a combination of axial, sagittal, and coronal images. (b) Buccal and palatal/lingual bone levels—measurement in frontal and/or axial views from a reference line at CEJ, according to Figure 1a, to the buccal and palatal/lingual marginal bone crest, respectively. (c) Mesial and distal bone levels—measurement from a reference line at CEJ to the mesial and distal marginal bone crest, respectively. An adjusted axial view was used to determine the level of the reference line between the mesial and distal CEJ.