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26 I I research _ CBCT Additionally, in cases in which teeth are assessed after trauma and in emergency cases, its appli- cation can be a useful aid in reaching a proper diagnosis and treatment approach.46,55,73–74 Recently, owing to its reliability and accu- racy, CBCT has also been used to evaluate the canal preparation in different instrumentation techniques.75–76 Implantology With increased demand for replacing missing teeth with dental implants, accurate measure- ments are needed to avoid damage to vital structures. This was achievable with conven- tional CT. However, with CBCT giving more accurate measurements at lower dosages, it is the preferred option in implant dentistry today (Figs. 4a & b).2,6,11,18,70,77–89 With new software that constructs surgical guides, damage is also reduced further.77,84,90–93 Heiland et al.94 describe a technique in which CBCT was used inter-operatively in two cases to navigate the implant insertion following mi- crosurgical bone transfer. CBCT enables the assessment of bone quality and bone quantity.18,26,70,80–81,85,88,95–97 This leads to reduced implant failure, as case selection can be based on much more reliable information. This advantage is also used for post-treatment evaluation and to assess the success of bone grafts (Figs. 5a–d).18,88 Orthodontics Orthodontists can use CBCT images in ortho- dontic assessment and cephalometric analy- sis.6,70,84,98–99 Today, CBCT is already the tool of choice in the assessment of facial growth, age, airway function and disturbances in tooth erup- tion.100–103 CBCT is a reliable tool in the assessment of the proximity to vital structures that may interfere withorthodontictreatment.104–105 Incasesinwhich mini-screw implants are placed to serve as a temporary anchorage, CBCT is useful for ensuring a safe insertion106–108 and to assess the bone den- sitybefore,duringandaftertreatment(Fig.6).109–110 Having different views in one scan, such as frontal, right and left lateral, 45-degree views and sub-mental, also adds to the advantages of CBCT.111,124 As the images are self-corrected from the magnification to produce orthogonal imageswith1:1ratio,higheraccuracyisensured. CBCT is thus considered a better option for the clinician.113 Temporomandibular joint disorder One of the major advantages of CBCT is its ability to define the true position of the condyle in the fossa, which often reveals possible dis- location of the disk in the joint, and the extent of translation of the condyle in the fossa.18,56,114 With its accuracy, measurements of the roof of the glenoid fossa can be done easily.115–116 An- other advantage of some of the available devices is their ability to visualise soft tissue around the TMJ, which may reduce the need for magnetic resonance imaging in these cases.117 Owing to these advantages, CBCT is the imag- ing device of choice in cases of trauma, pain, dys- function, fibro-osseous ankylosis and in detect- ing condylar cortical erosion and cysts.70,87,118–120 With the use of the 3-D features, the image- guided puncture technique, which is a treatment modality for TMJ disk adhesion, can safely be performed.121 Periodontics CBCT can be used in assessing a detailed mor- phologic description of the bone because it has proved to be accurate with only minimal error Fig. 5a_Clinical picture of multiple implants placed in 2005. Fig. 5b_Peri-apical radiograph for the implants replacing teeth #8 and #9. Little data can be collected from such an image. Fig. 5c_The CBCT image clearly demonstrates the amount of bone loss. CAD/CAM 2_2010 Fig. 5a Fig. 5b Fig. 5c