RESUMO
Objective:To evaluate of the feasibility of low-dose CT(LDCT)in the reconstruction of three-dimensional(3D)model of maxillofacial hard and soft tissues.Methods:Lightspeed 16-slice spiral CT scanner was used to scan one adult cadaveric head specimens with conventional parameters(280 mA)and low dose parameters(200,150,100,50,35,25,15 and 5 mA)respectively;the 3D model of the hard and soft tissues were reconstructed with Mimics 10.01 software,and 3D comparison were carried on with Geomagic 11.0 software.A comparison of the surface morphology of the hard and soft tissues of the 3D models with different scanning parameters was made.Results:With the reduction of the tube current,the model surface became rough gradually.Compared with the 280 mA scan results,the model surface produced by 35 mA scanning was still fairing,when the dose fell to less than 25 mA,the model surface became rough and the exact shape of the model could not be recognized.The same results of model surface were pro-duced after registration.Conclusion:The low-dose (35 mA)CT can be used to reconstruct 3D model of the maxillofacial hard and soft tissues.