A Comparative Study On Accuracy Of The Measurement Of Teeth Length Using Digital Dental Films, Panoramic Radiography And CBCT On The Measurement

Objective:Compare the accuracy of digital dental films, panoramic radiography and CBCT on the measurement of the tooth length. Thus, offer reference for dental clinical practice.Method:160single root premolars that were selected from patients due to fixed orthodontic treatment. The lengths of the tooth were measure by Vernier caliper.10groups were divided by the use of completely randomized design and there were16teeth in each group. The teeth were lined in molar area (?), premolar area (?), canine area (?) and anterior teeth area (?) of the Skull specimen, respectively. And there were8areas in total. Then the digital dental films, panoramic radiography and CBCT were taken, and the tooth length were measured according to image by the software supplied by the manufacturer of the imagining machine. Thus, results were compared with the real tooth length.Results:1.These are no statistical difference between the results taken by digital dental films and the real tooth length.(p>0.05).2.These is statistical differences between the results taken by panoramic radiography and the real tooth length (p<0.05). Average distortion rate was17.05%.3.The coronal results of CBCT measurements showed, except from the maxillary premolar area and mandibular premolar area, which has no statistical differences (P>0.05), the rest of the six areas have statistical differences (P<0.05).4.The measurement results of vector plane showed that the tooth lengths of maxillary molar area, mandibular molar area, mandibular premolar area, mandibular canine area, mandibular anterior teeth area are all less than the results drew from real tooth length (p<0.05), which have statistical differences compared with each other.the rest of the3areas have no statistical differences (P>0.05)5.There was a correlation between the buccal and lingual torque angle of the tooth and the tooth length taken by CBCT (spearman=6.00, P<0.001). There was a correlation between the tipping angle of the tooth and the tooth length taken by CBCT (spearman=6.00, P<0.001)Conclusion:1.Digital dental films would show the real tooth length more accurate rather than panoramic radiography and CBCT.2.CBCT radiograph can not show the real tooth length accurately with the proportion of1to1. The torque angle and the tipping angle have influences on the accuracy of measurement of tooth length.