Scientific Publications on CBCT - March 2010

Comparison of Five Cone Beam Computed Tomography Systems for the Detection of Vertical Root Fractures.

Hassan B., Metska M.E., Ozok A.R., van der Stelt P., Wesselink P.R.

Journal of Endodontics. 36(1)(pp 126-129), 2010. Date of Publication: January 2010.

AB Introduction: This study compared the accuracy of cone beam computed tomography (CBCT) scans made by five different systems in detecting vertical root fractures (VRFs). It also assessed the influence of the presence of root canal filling (RCF), CBCT slice orientation selection, and the type of tooth (premolar/molar) on detection accuracy. Methods: Eighty endodontically prepared teeth were divided into four groups and placed in dry mandibles. The teeth in groups Fr-F and Fr-NF were artificially fractured; those in groups control-F and control-NF were not. Groups Fr-F and control-F were root filled. CBCT scans were made using five different commercial CBCT systems. Two observers evaluated images in axial, coronal, and sagittal reconstruction planes. Results: There was a significant difference in detection accuracy among the five systems (p = 0.00001). The presence of RCF did not influence sensitivity (p = 0.16), but it reduced specificity (p = 0.003). Axial slices were significantly more accurate than sagittal and coronal slices (p = 0.0001) in detecting VRF in all systems. Significantly more VRFs were detected among molars than premolars (p = 0.0001). Conclusions: RCF presence reduced specificity in all systems (p = 0.003) but did not influence accuracy (p = 0.79) except in one system (p = 0.012). Axial slices were the most accurate in detecting VRFs (p = 0.0001). copyright 2010 American Association of Endodontists.

Cone Beam CT for Diagnosis and Treatment Planning in Trauma Cases.

Palomo L., Palomo J.M.

Dental Clinics of North America. 53(4)(pp 717-727), 2009. Date of Publication: October 2009.

AB Three-dimensional imaging offers many advantages in making diagnoses and planning treatment. This article focuses on cone beam CT (CBCT) for making diagnoses and planning treatment in trauma-related cases. CBCT equipment is smaller and less expensive than traditional medical CT equipment and is tailored to address challenges specific to the dentoalveolar environment. Like medical CT, CBCT offers a three-dimensional view that conventional two-dimensional dental radiography fails to provide. CBCT combines the strengths of medical CT with those of conventional dental radiography to accommodate unique diagnostic and treatment-planning applications that have particular utility in dentoalveolar trauma cases. CBCT is useful, for example, in identifying tooth fractures relative to surrounding alveolar bone, in determining alveolar fracture location and morphology, in analyzing ridge-defect height and width, and in imaging temporomandibular joints. Treatment-planning applications include those involving extraction of fractured teeth, placement of implants, exposure of impacted teeth, and analyses of airways. copyright 2009 Elsevier Inc. All rights reserved.

Relationship between occlusal force and mandibular condyle morphology.

Kurusu A., Horiuchi M., Soma K.

Angle Orthodontist. 79(6)(pp 1063-1069), 2009. Date of Publication: November 2009.

AB Objective: To clarify the relationship between occlusal force and mandibular condyle morphology using clinical data. Materials and Methods: The subjects were 40 female patients with malocclusion. The mandibularcondyle morphology was assessed by using limited cone-beam CT imaging. The maximum occlusal force was calculated by using pressure-sensitive films. Maxillofacial morphologies were analyzed by using data from lateral cephalograms. Results: Correlation analysis showed that the occlusal force was correlated with the lateral and posterior radii of the condyles, and with the mandibular plane angle to the Frankfort horizontal plane (FH). Moreover, condylar length was significantly correlated with the occlusal plane angle to the FH, the mandibular plane angle to the FH, the ramus inclination, and the posterior facial height (S-Go). Low-occlusal-force patients tended to have smaller mandibular condyles. This size related difference was more remarkable on the lateral and posterior side. Conclusions: Occlusal force influences not only maxillofacial morphology but also mandibularcondyle morphology. (Angle Orthod. 2009;79:1063-1069.) copyright 2009 by The EH Angle Education and Research Foundation, Inc.

Reliability of traditional cephalometric landmarks as seen in three-dimensional analysis in maxillary expansion treatments.

Lagravere M.O., Gordon J.M., Guedes I.H., Mir C.F., Carey J.P., Heo G., Major P.W.

Angle Orthodontist. 79(6)(pp 1047-1056), 2009. Date of Publication: November 2009.

AB Objective: To evaluate intra-examiner and inter-examiner reliability of 3D CBCT-generated landmarks previously used in traditional 2D cephalometry. Materials and Methods: Twenty-four CBCTs NewTom 3G (Aperio Services, Verona, Italy) were randomly selected from patients participating in a clinical trial involving maxillary expansion treatments.The principal investigator located the landmarks five times, and four other investigators located the same landmarks once. Intra-examiner and inter-examiner reliability values were determined using intraclass correlation coefficients (ICCs). To assist in interpretation of the clinical significance of landmark identification differences, average mean differences for x, y, and z landmark coordinates were determined from the repeated assessments. Landmarks then were separated into groups with respect to the region they represented and then were compared via repeated measures ANOVA and multiple comparisons via Bonferroni corrected .Results: Intra-examiner and inter-examiner reliability for x, y, and z coordinates for all landmarks were acceptable, all being greater than 0.80. Most of the mean measurement differences obtained from trials within the principal investigator in all three axes were less than 1.5 mm. Inter-examiner mean measurement differences generally were larger than the intra-examiner differences.Conclusions: Based on this, the best landmarks for use in verifying expansion treatment results are Ekm, buccal surface, and apexes of upper molars, upper premolars and upper canines, and buccal surfaces of lower molars and lower canines. Foramen Spinosum, ELSA, Auditory External Meatus, and Dorsum Foramen Magnum demonstrated adequate reliability for determining a standardized reference system. (Angle Orthod. 2009;79:1047-1056.) copyright 2009 by The EH Angle Education and Research Foundation, Inc.

Variable-resolution cone-beam computerized tomography with enhancement filtration compared with intraoral photostimulable phosphor radiography in detection of transverse root fractures in an in vitro model.

Wenzel A., Haiter-Neto F., Frydenberg M., Kirkevang L.-L.

Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology and Endodontology. 108(6)(pp 939-945), 2009. Date of Publication: December 2009.

AB Objectives: The aim of this study was to compare the diagnostic accuracy of an intraoral photostimulable storage phosphor (PSP) plate system and cone-beam computerized tomography scanning (CBCT) for detection of experimentally induced transverse root fractures and to evaluate differences between original images and images enhanced with high-pass filters. Study design: Sixty-nine extracted human teeth, 34 with root fractures and 35 without, were examined under standardized conditions using an intraoral PSP system (Digora Optime; Soredex). The images were saved in original 8-bit format and in a version sharpened with a high-pass filter. The teeth were examined with CBCT (i-Cat; Imaging Sciences) in 2 resolutions: 0.125 mm and 0.25 mm voxel size. Original images were saved together with images enhanced with 2 high-pass filters, sharpen and angio-sharpen. Six observers scored the presence of a root fracture in all modalities in random order. Sensitivity, specificity, and accuracy [(true positives + true negatives)/all scores] were calculated for each modality and each observer. Differences were estimated by analyzing the binary data, assuming additive effects of observer and modality in a generalized linear model. Results: High-resolution original CBCT images had higher sensitivity (P < .05) than lower-resolution images and PSP images (0.125 mm resolution 87%, 0.25 mm resolution 72%, and PSP 74%). Angio-sharpen-filtered images for both CBCT resolutions had higher sensitivities (P < .02) than the original images (0.125 mm resolution: 95% vs. 87%; 0.25 mm resolution: 81% vs. 72%). There was no significant difference between the lower-resolution CBCT and PSP images. Only small differences in specificity were seen between modalities, and accuracy was higher for high-resolution CBCT than for the other modalities (P < .03). Conclusions: High-resolution i-Cat CBCT images resulted in an increase in sensitivity without jeopardizing specificity for detection of transverse root fractures compared with lower-resolution CBCT images, which were not more accurate than periapical PSP images. The angio-sharpen high-pass filter improved sensitivity in the high-resolution CBCT images in this in vitro model. copyright 2009 Mosby, Inc. All rights reserved.

Guest editorial--Self-referral: an ethical concern with respect to multidimensional imaging in dentistry?.

Farman A.G.

Journal of applied oral science : revista FOB. 17(5), 2009. Date of Publication: 2009 Sep-Oct.

Case report: Cone-beam ct imaging in the management of a double tooth..

Lucey S., Heath N., Welbury R.R., Wright G.

European archives of paediatric dentistry : official journal of the European Academy of Paediatric Dentistry. 10 Suppl 1(pp 49-53), 2009. Date of Publication: Nov 2009.

AB BACKGROUND: The diagnosis and management strategies of double teeth have largely relied on clinical examination and conventional radiographic findings. Cone-Beam Computed Tomography (Cone-beam CT) was developed in the late 1990's and, therefore, is a relatively recent addition to the imaging armamentarium for use in Maxillofacial Radiology. There have been no publications in the dental literature demonstrating the use of Cone-beam CT or 3D stereolithography in the diagnosis and surgical planning of the management of double teeth. CASE REPORT: An 11 year old girl presented with a double left lateral maxillary incisor. Conventional plain film radiography failed to provide the requisite information for pre-operative planning. Cone-beam Computed Tomography (Cone-beam CT) allowed determination of location of fusion, three-dimensional (3D) visualisation of pulpal anatomy and the construction of a 3D stereolithographic model for surgical planning. The double tooth was surgically divided in situ under local analgesia. The redundant distal unit was extracted and the residual mesial unit built up in composite resin following physiological mesial drift of displaced maxillary left canine. No endodontic therapy was required. FOLLOW-UP: At a 10-month follow-up visit, clinical and radiographic vitality and success was noted. CONCLUSION: The great amount of radiological information which Cone-beam CT can offer not only improves pre-operative and surgical planning, but the 3D models provided can be used to further educate and inform patients and guardians in the management of double teeth.

Radiographs in periodontal disease diagnosis and management..

Corbet E.F., Ho D.K., Lai S.M.

Australian dental journal. 54 Suppl 1(pp S27-43), 2009. Date of Publication: Sep 2009.

AB Radiographs are an integral component of a periodontal assessment for those with clinical evidence of periodontal destruction. A close consideration of the current approach to periodontal diagnosis compatible with the current classification of periodontal diseases reveals that radiographs only inform with respect to diagnosis for a small proportion of conditions. The area in periodontal assessment in which radiographs play a pivotal role is in treatment planning. A variety of radiographic exposure types assist in the development of periodontal treatment plans. This "therapeutic yield" can be achieved by panoramic oral radiographs supplemented by selective intra-oral views. Digital panoramic oral radiographs viewed on screen appear to offer advantages over printouts or films. Newer imaging approaches, such as cone-beam computed (digital volume) tomography, may come to show some usefulness but experience has shown that digital subtraction radiography will probably remain a research tool without much clinical application.

A comparison between 2D and 3D cephalometry on CBCT scans of human skulls.

van Vlijmen O.J.C., Maal T., Berge S.J., Bronkhorst E.M., Katsaros C., Kuijpers-Jagtman A.M.

International Journal of Oral and Maxillofacial Surgery. 39(2)(pp 156-160), 2010. Date of Publication: February 2010.

AB The purpose of this study was to evaluate whether measurements on conventional cephalometric radiographs are comparable with 3D measurements on 3D models of human skulls, derived from cone beam CT (CBCT) data. A CBCT scan and a conventional cephalometric radiograph were made of 40 dry skulls. Standard cephalometric software was used to identify landmarks on both the 2D images and the 3D models. The same operator identified 17 landmarks on the cephalometric radiographs and on the 3D models. All images and 3D models were traced five times with a time-interval of 1 week and the mean value of repeated measurements was used for further statistical analysis. Distances and angles were calculated. Intra-observer reliability was good for all measurements. The reproducibility of the measurements on the conventional cephalometric radiographs was higher compared with the reproducibility of measurements on the 3D models. For a few measurements a clinically relevant difference between measurements on conventional cephalometric radiographs and 3D models was found. Measurements on conventional cephalometric radiographs can differ significantly from measurements on 3D models of the same skull. The authors recommend that 3D tracings for longitudinal research are not used in cases were there are only 2D records from the past. copyright 2009 International Association of Oral and Maxillofacial Surgeons.

A review of the diagnosis and management of impacted maxillary canines.

Bedoya M.M., Park J.H.

Journal of the American Dental Association. 140(12)(pp 1485-1493), 2009. Date of Publication: December 2009.

AB Background. The authors conducted a literature r review regarding the clinical and radiographic diag-noses of impacted maxillary canines, as well as the interceptive treatment (including surgical and orthodontic management) used to prevent or properly treat impacted canines. Types of Studies Reviewed. The authors reviewed clinical and radiographic studies, literature reviews and case reports. They selected only studies that pertained to the prevalence, etiology and diagnosis of impacted maxillary canines, as well as the most recent studies regarding surgical and orthodontic techniques for the proper management of impacted maxillary canines. Results. Impacted canines can be detected at an early age, and clinicians might be able to prevent them by means of proper clinical diagnosis, radiographic evaluation and timely interceptive treatment. Surgical techniques that can be used to manage impacted canines vary depending on whether the impactions are labial or palatal, and orthodontic techniques vary according to clinical judgment and experience. Clinical Implications. Canine impaction is a common occurrence, and clinicians must be prepared to manage it. With early detection, timely interception, and well-managed surgical and orthodontic treatment, impacted maxillary canines can be erupted and guided to an appropriate location in the dental arch.