Reproducibility of a hemi mandible positioning device and a method for measuring alveolar bone loss area in mice

The objective of this study was to determine the reproducibility of a positioning device and a method for measuring the area of alveolar bone loss (ABL) in hemi mandibles of mice. Mucoperiosteal flaps were raised in CF1 Mus domesticus mice (n = 10) on the buccal aspects of the left side of the mandibles. Twenty-one days after surgery, the animals were sacrificed, and the mandibles were resected and stained with 1% toluidine blue. Two positioning devices, one for the buccal and the other for lingual aspect, were fabricated to keep the hemi mandibles in a standard position. The reliabilities of the positioning device and the method for measuring ABL area were analyzed using two series of pictures. The photographs were digitized and ABL measured as the exposed root area. Measurements were performed by two blinded examiners using image analysis software. Intra- and inter-examiner reproducibility of the positioning method ranged from -1.5 to +1.33 mm, while intra- and inter-examiner reproducibility of the measurement technique ranged from -3.37 to 14.70. Our results indicate that, due to the small variation observed in ABL area assessment, the positioning device and method for measuring ABL area represent useful techniques for evaluating ABL in mice.