OBJECTIVETo study anatomic and computed tomographic measurements of Chinese mandibular genial tubercles and to evaluate the correlations between them.

METHODSThe axial images were taken by spiral CT in 40 adult human skulls with 1 mm thick section from infraorbital margin to menton. Sagittal plane reconstruction was produced through mandibular central line. Then the height and width of superior genial tubercles, the distance between menton and inferior margin of genial tubercles, the distance between mandibular incisor apex and superior margin of superior genial tubercles, the thickness of mandible were measured respectively. Thereafter anatomic measurements were taken by the same methods as computed tomographic images. The measured value were showed as means +/- standard deviation, then paired-t test and correlation analysis was made by SPSS 10.0.

RESULTSThe genioglossus almost origins from superior genial tubercles, geniohyoideus from inferior genial tubercles. The height of superior genial tubercles which were measured by anatomy and spiral CT were (5.82 +/- 0.71) mm and (6.17 +/- 0.71) mm respectively. The width of superior genial tubercles were (6.98 +/- 1.35) mm and (7.01 +/- 1.13) mm. The distance between menton and inferior margin of superior genial tubercles were (11.08 +/- 2.05) mm and (10.41 +/- 1.55) mm. The distance between mandibular incisor apex and superior margin of superior genial tubercles for male were (15.57 +/- 1.82) mm and (14.34 +/- 2.06)mm, and for female were (9.36 +/- 2.79) mm (8.78 +/- 2.53) mm. The thickness of mandibles at genial tubercles were (11.95 +/- 1.59) mm and (12.19 +/- 1.64) mm. The distance from menton to superior margin of superior genial tubercles were (16.1 +/- 2.30) mm and (15.73 +/- 2.12) mm. The correlations between anatomic measurements and spiral CT measurements of the above mentioned parameters were significant except for height of superior genial tubercles (r = 0.59 - 0.92).

CONCLUSIONThe anatomic and spiral CT measurements of genial tubercles appear to have significant correlations. Preoperative spiral CT measurements of genial tubercles could be help for the design of osteotomy in genioglossus advancement.