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I 33 research _ CBCT I roots4_2010 CBCT is largely used in orthognathic surgery planning when facial orthomorphic surgery is indicated that requires detailed visualisation of the inter-occlusal relationship in order to aug- ment the 3-D virtual skull model with a detailed dental surface. With the aid of advanced soft- ware, CBCT facilitates the visualisation of soft tissue to allow for control of post-treatment aesthetics, for example in cleft palate cases to evaluate lip and palate bony depressions.37–42 Research is underway to assess its ability to detect salivary gland defects.43 Honda et al.44 describe a clinical case in which the time needed to complete a tooth auto-transplant case was significantly shortened owing to the application of CBCT. Endodontics CBCT is a very useful tool in diagnosing apical lesions (Figs. 2a & b).21,45–56 A number of studies have demonstrated its ability to enable a diffe- rentialdiagnosisofapicallesionsbymeasuringthe density from the contrasted images of these le- sions, in whether the lesion is an apical granuloma or an apical cyst (Figs. 3a & b).49,55–57 Cotton etal.46 used CBCT as a tool to assess whether the lesion was of endodontic or non-endodontic origin. CBCT also demonstrated superiority to 2-D radiographs in detecting fractured roots. Vertical and horizontal root fracture detection is de- scribed in several clinical cases.21,46,55–59 It is also agreed that CBCT is superior to peri-apical radi- ographs in detecting these fractures, whether they are bucco-lingual or mesiodistal.60–61 In cases with inflammatory root resorption, lesions are detected much easier in early stages with CBCT compared to conventional 2-D X-ray.21,62 In other cases, such as external root resorption, externalcervicalandinternalresorption,notonly the presence of resorption was detected, but also the extent of it.21,46,54,56,63–64 CBCT can also be used to determine root morphology, the number of roots, canals and accessory canals, as well as to establishing the working length and angulations of roots and canals.21,25,46,55–56,58,65–67 It also is accurate in as- sessing root-canal fillings.47,51,56,58 Owing to its accuracy, it is very helpful in detecting the pulpal extensions in talon cusps68 and the position of fractured instruments.69 It is also a reliable tool for pre-surgical as- sessment of the proximity of the tooth to adja- cent vital structures, size and extent of lesions, as well as the anatomy and morphology of roots with very accurate measurements.21,46,48,50,54–58,69–72 Figs. 3a & b_Apical cyst shown as orthopantomogram (a) and CBCT (b). Fig. 4a_Orthopantomogram for a full-mouth rehabilitation case. Only limited data can be obtained from this image. Fig. 4b_CBCT images for the same patient. Data obtained from these images regarding bone quality, implant length and diameter, implant location and proximity to vital structures is magnificent. Fig. 4bFig. 4a Fig. 3bFig. 3a Specialty Number of articles in % Oral and maxillofacial surgery 36 26.86 Endodontics 32 23.88 Implantology 22 16.42 Orthodontics 16 11.94 General dentistry 14 10.45 Temporomandibular joint disorder 8 5.97 Periodontics 5 3.73 Forensic dentistry 1 0.75 Table I