Fig. 3

Measurement of molar furcation involvement on CBCT scans. a a schematic diagram illustrates measurement of furcation bone loss of a maxillary first molar. Dotted line represents tangent line connecting two adjacent root surfaces. Arrows represent distances from the middle of tangent line to the deepest point of bone loss at the different surfaces. Red, green, and blue arrows denote furcation bone loss at buccal, mesial palatal, and distal palatal surface of the molar, respectively. MB, mesial buccal root; DB, distal buccal root; and P, palatal root. b a representative CBCT axial view demonstrates measurements of furcation bone loss of a maxillary first molar. c a schematic diagram illustrates measurement of furcation bone loss of a mandibular first molar. Dotted line represents tangent line connecting buccal or lingual surfaces of the two roots, respectively. Arrows represent distances from the middle of tangent line to the deepest point of bone loss at the different surfaces. Red and green arrows denote furcation bone loss at buccal and lingual surface of the molar, respectively. M, mesial root; and D, distal root. d a representative CBCT axial view demonstrates measurements of furcation bone loss of a mandibular first molar