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I 21 case report _ root fractures I roots1_2011 Saving a tooth via intentional extraction causes minimal damage to periodontal tissues. 4-META/ MMA-TBB resin is generally used to bond the sepa- rated fragments and afterwards, replantation is per- formed.8,9 Thedistancebetweenseparatedfracturesis animportantfactortodeterminewhethersurgerywill be planned with simultaneous flap operation or with normalextractionwithoutflapreflection.4 Inaddition, determining the position and extent of the fracture might be helpful for deciding when to recommend extraction. ArootfracturecanbeoverlookediftheX-raybeam does not pass along the fracture line.10 Furthermore, the interpretation of root fracture on radiographs is problematic, especially if there is no oedema and granulationtissuebetweentheseparatedfragments.11 Another major problem for conventional intra-oral radiography is the superimposition of other struc- tures, which limits the sensitivity of diagnosis.12 Cone-Beam Computed Tomography (CBCT) units have become commercially available recently, in which all data is acquired at one time, providing a 3-D scan of the patient’s head.13–15 Previous studies have indicated the superiority of CBCT to intra-oral conventional film and digital radiography for detect- ing VRFs.12,14–17 A recent study reported that CBCT scans had provided more accurate results than intra- oral radiography during the diagnosis of VRFs with 0.2 to 0.4mm thicknesses, which may indicate the early stages of the problem (Figs. 1a–d).16 Choosing the appropriate radiation dose using CBCTindetectingVRFsisamajorandcriticalconcern. ALARA is the acronym for as low as reasonably achievable, which constitutes the basic principle for diagnostic radiology in all fields. One must consider keeping the dose as low as possible while still obtaining the information needed.18 It is reported thatwithsmallervoxelsizes,radiationexposurewould be higher.19–21 Without sacrificing image quality and adoptingtheALARAprinciple,changingthevoxelset- tings would be helpful in reducing the radiation dose. Recentstudiescomparingthediagnosticaccuracy ofdifferentvoxelsizesforthedetectionofVRFsreport thatvoxelsizesequaltoorsmallerthan0.2mmarethe bestchoice,withashorterscanningtimeandreduced radiation exposure of the patient (Figs. 2a–d).22,23 AfterdiagnosingtheVRF,arapiddecisionhastobe madewhethertoextractorretainthetooth.Extra-oral VRF treatment that includes resin cement bonding and intentional replantation is an alternative treat- ment modality. This alternative treatment method in particular is reported to be appropriate for anterior teeth.4,8,24,25 A clinical report by Hayashi etal. demon- strated no failure in vertically fractured incisors treated with this method, although failures occurred in premolars and molars in that the posterior teeth were negatively affected by strong occlusal forces.25 For a vertically fractured incisor, Öztürk and Ünal reported a successful four-year outcome clinically.4 Similarly,Arıkanetal.reportedasuccessful18-month outcome for VRF treatment and recommended the proceduredescribedinthisarticle.24 Theyalsodemon- strated that the use of a dual-curing material instead of 4-META/MMA-TBB resin shortened extra-oral working time and preserved the vitality of the peri- odontal ligament, thereby increasing the probability of long-term replantation success. In addition, Özer et al. reported success after two years in treatment outcomes of VRFs treated in the same manner as above.26 _Alternative treatment of VRFs ThealternativetreatmentplanforVRFsconsistsof the following steps: 1.Extraction of affected teeth; 2.Bonding of the separated segments with a self- etching, dual-cure adhesive resin cement extra- orally; and 3.Intentionalreplantationofthereconstructedteeth. Figs. 2a–d_CBCT images of a fractured root with four different voxels in the axial plane. 0.125mm voxel (a); 0.2mm voxel (b); 0.3mm voxel (c); 0.4mm voxel (d). Fracture lines are difficult to detect when compared with the 0.125mm and 0.2mm voxels. Fig. 2c Fig. 2d Fig. 2a Fig. 2b